JP2017014687A - Electric work auxiliary system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To mitigate a load on an operator.SOLUTION: An electric work auxiliary system comprises: a construction machine comprising a traveling body, a revolving superstructure provided on the traveling body, a work device provided on the revolving superstructure, a hydraulic pump for supplying pressure oil for driving each of the traveling body, the revolving superstructure, and the work device, and an electric motor for driving the hydraulic pump; a power supply vehicle comprising a power supply device for supplying power, through a cable, to the electric motor mounted on the construction machine; an imaging device provided in at least either of the construction machine and the power supply vehicle; and a control device for determining whether or not a distance between the construction machine and the cable is shorter than a predetermined distance, on the basis of a picture imaged by the imaging device. The control device, when it has been determined that distance between the construction machine and the cable is shorter than the predetermined distance, transmits predetermined information to an information terminal.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an electric work assistance system.

  In recent years, there has been a growing demand for energy saving and environmental resistance improvement at the construction machine work site. In response, construction equipment manufacturers are providing electric construction machines that are equipped with electric motors instead of engines and drive hydraulic systems. Patent Document 1 describes an electric construction machine that can be connected via a cable to a power supply vehicle that includes a battery and an inverter connected to the battery.

JP 2014-118773 A

  Since the electric construction machine described in Patent Document 1 is connected to the power supply vehicle via a cable, the driver works with care so that the cable is not stepped on by the crawler. There was a problem that it was necessary and the burden on the driver was large.

  The electric work assist system according to claim 1 drives each of the traveling body, the swing body provided on the travel body, the work device provided on the swing body, and the travel body, the swing body, and the work device. Power supply vehicle including a hydraulic pump that supplies pressure oil for use, a construction machine having an electric motor that drives the hydraulic pump, and a power supply device that supplies power to the electric motor mounted on the construction machine via a cable And a control device for determining whether or not the distance between the construction machine and the cable is smaller than a predetermined distance based on an imaging device provided in at least one of the construction machine and the power supply vehicle and an image captured by the imaging device The control device transmits predetermined information to the information terminal when it is determined that the distance between the construction machine and the cable is smaller than the predetermined distance.

  According to the present invention, when the cable approaches the construction machine, it is possible to notify the driver, the field worker, the site supervisor, etc. via the information terminal, so that the burden on the driver can be reduced.

A side view and a top view of a hydraulic excavator which is an example of a construction machine. The schematic diagram explaining the common support stand which supports an engine or an electric motor. The perspective view which shows the bracket for engines and a common support stand. The side surface schematic diagram which shows the structure of the electric work assistance system which concerns on 1st Embodiment. The block diagram which shows the structure of an electrically-driven work assistance system. (A) is a schematic plan view showing the positional relationship between the hydraulic excavator and the power supply vehicle, (b) is a schematic diagram showing a symbol mark painted on the rear surface of the counterweight of the hydraulic excavator, and (c) is taken by a camera. FIG. 4D is a diagram for explaining how to obtain the length per pixel, and FIG. 4E is a diagram for explaining how to obtain the shortest distance between the crawler and the cable. The flowchart which shows the content of the cable winding drive process and overload warning transmission process by a controller. The plane schematic diagram which shows an example of the change of the relative position of a hydraulic excavator and a power supply vehicle. The plane schematic diagram which shows the hydraulic excavator, power supply vehicle, and cable which comprise the electric work assistance system which concerns on 2nd Embodiment. (A) is a flowchart which shows an example of the alarm transmission process in the controller which concerns on 3rd Embodiment. (B) is a flowchart which shows an example of the alarm transmission process in the controller which concerns on 4th Embodiment. The flowchart which shows an example of the cable winding drive process in the controller which concerns on 5th Embodiment. The schematic diagram which shows an example of the arrangement | positioning state of a cable. The side surface schematic diagram which shows the structure of the electric work assistance system which concerns on the modification 2. As shown in FIG. The flowchart which shows an example of the approach warning transmission process in a controller. The schematic diagram which shows the structure of the electrically-driven work assistance system which concerns on the modification 5. FIG.

-First embodiment-
Fig.1 (a) and FIG.1 (b) are the side views and top views of the hydraulic excavator 100 which are examples of a construction machine. For convenience of explanation, the front and rear, the top and bottom, and the left and right directions of the excavator 100 are defined based on the posture of FIG. A hydraulic excavator 100 illustrated in FIG. 1 includes a traveling body 102 and a revolving body 105 provided on the traveling body 102. The turning body 105 is provided so as to be turnable with respect to the traveling body 102 by a turning mechanism. The turning mechanism is provided with a hydraulic motor (hereinafter referred to as a turning motor) for turning the turning body 105.

  The traveling body 102 is mounted with a traveling hydraulic motor (hereinafter referred to as a traveling motor 106). The traveling body 102 travels by driving the left and right crawlers 103 by the left and right traveling motors 106.

  A front working device 110 that performs excavation work is provided at the front of the revolving structure 105. The front work device 110 includes a boom 107, an arm 108, and a bucket 109. The boom 107 is attached so as to be rotatable in the vertical direction with respect to the swing body 105 in a frame constituting the swing body 105 (hereinafter referred to as a swing frame 105f). The boom 107 is driven by a boom raising / lowering hydraulic cylinder (hereinafter referred to as a boom cylinder 107a) to rise and fall.

  The arm 108 is attached to the boom 107 so as to be rotatable in the vertical direction with respect to the boom 107. The arm 108 is driven to rise and fall by a hydraulic cylinder for raising and lowering the arm (hereinafter referred to as an arm cylinder 108a). The bucket 109 is attached at the tip of the arm 108 so as to be pivotable in the vertical direction with respect to the arm 108, and is driven by a hydraulic cylinder for raising and lowering the bucket (hereinafter referred to as a bucket cylinder 109a).

  The swivel body 105 is provided with a cab 104 where a driver operating the excavator 100 rides. Various operation members are disposed in the cab 104. A counterweight 101 is disposed at the rear part of the revolving unit 105 in order to balance the front working device 110. As shown in FIG. 1B, an electric motor 111 and a hydraulic pump 112, a small generator 113, and an auxiliary battery 114 are disposed in front of the counterweight 101 in the swing body 105. The upper surface side and the side surface side of the electric motor 111 and the hydraulic pump 112 are covered with a building cover 119 (see FIG. 1A, not shown in FIG. 1B).

  The rotation shafts of the electric motor 111, the hydraulic pump 112, and the small generator 113 extend in the left-right direction of the hydraulic excavator 100, respectively. The electric motor 111 is rotationally driven by electric power supplied from a power supply car 130 (see FIG. 4) described later.

  The hydraulic pump 112 is driven by the electric motor 111 to discharge hydraulic oil. The hydraulic oil discharged from the hydraulic pump 112 is turned to drive each of the actuators (the boom cylinder 107a, the arm cylinder 108a, and the bucket cylinder 109a) that drives the front work device 110 and the turning mechanism via a control valve (not shown). A motor (not shown) is supplied to a traveling motor 106 that drives the traveling body 102. That is, the hydraulic pump 112 is driven by the electric motor 111 that is a driving source, and the hydraulic oil is supplied from the hydraulic pump 112 to each actuator, whereby each of the traveling body 102, the swinging body 105, and the front work device 110 is driven. The

  The small generator 113 generates electricity when the electric motor 111 rotates. The electric power generated by the small generator 113 is supplied to the auxiliary battery 114, and the auxiliary battery 114 is charged. The auxiliary battery 114 is a power supply device that supplies electric power to various auxiliary machines and controllers arranged in the cab 104.

  FIG. 2 is a schematic diagram for explaining the common support stand 125 that supports the engine 191 or the electric motor 111. In the present embodiment, instead of the electric motor 111, a shared support base 125 having a strength and shape capable of supporting the engine 191 is provided. FIG. 2A shows a state where the engine 191 is connected to the common support base 125 via the engine bracket 129 and the engine 191 is supported by the common support base 125. FIG. 2B shows a state in which the electric motor 111 is connected to the common support base 125 via the motor bracket 121, and the electric motor 111 is supported by the common support base 125.

  FIG. 3 is a perspective view showing the engine bracket 129 and the shared support base 125. FIG. 3 is an overall perspective view (upper right view) of the turning frame 105f, an enlarged perspective view (lower right view) of a part of the turning frame 105f (A portion in the upper right view), and a perspective view (left view) of the engine 191. It is shown. A connection structure between the engine 191 and the shared support stand 125 will be described with reference to FIG. Note that the connection structure between the electric motor 111 and the common support base 125 is the same as the connection structure between the engine 191 and the common support base 125, and thus the description thereof is omitted.

  As shown in FIG. 3, a common support base 125 that supports the engine 191 (or the electric motor 111) is provided at the rear portion of the turning frame 105 f. The common support stand 125 includes a U-shaped holding frame 151 in plan view and four support legs 152 fixed to the holding frame 151. The holding frame 151 includes a pair of vertical plates 151a extending in the front-rear direction and a connecting plate 151b that connects the pair of vertical plates 151a at the front ends of the pair of vertical plates 151a.

  The four support legs 152 are provided with mounting plates 152a having mounting surfaces that are located on substantially the same plane. Each of the four support legs 152 includes a connecting portion that connects the mounting plate 152 a and the holding frame 151.

  Four engine brackets 129 are detachably attached to the engine 191. The mounting plate 152a is formed with a through hole 152h through which a bolt that is a component of the rubber mount 128 is inserted. Each engine bracket 129 is placed on a placement plate 152 a of each support leg 152. Each engine bracket 129 is attached to the mounting plate 152 a of the support leg 152 via the rubber mount 128.

  The engine bracket 129 is connected to each of the connection plate 129a connected to the side portion of the engine 191, the attachment plate 129b extending from the lower end of the connection plate 129a, the attachment plate 129b, and the connection plate 129a. Reinforcing ribs 129c that increase the rigidity of the bracket 129 are provided. When the mounting plate 129b and the connection plate 129a can secure sufficient rigidity of the engine bracket 129, the reinforcing rib 129c can be omitted. That is, when the engine 191 is supported by the common support base 125, the engine 191 is supported by the common support base 125 via the four engine brackets 129.

  Although not shown, when the electric motor 111 is attached to the common support base 125, four motor brackets 121 (see FIG. 2B) are attached to the electric motor 111, and the motor bracket 121 is attached to the support legs via the rubber mount 128. What is necessary is just to attach to the mounting board 152a of 152. Even when the electric motor 111 is attached, the bolt 121 constituting the rubber mount 128 is inserted into the through-hole 152h described above, and the nut is screwed to the tip of the bolt, so that the motor bracket 121 can be attached to the common support base 125. Can be fastened and fixed. That is, when the electric motor 111 is supported by the common support base 125, the electric motor 111 is supported by the common support base 125 via the four motor brackets 121. As described above, in the present embodiment, the structures of the engine bracket 129 and the motor bracket 121 are each configured to be attachable to the common support base 125.

  FIG. 4 is a schematic side view illustrating the configuration of the electric work assistance system according to the first embodiment. The electric work assistance system includes a hydraulic excavator 100, a power supply vehicle 130, and a cable 140 that connects the hydraulic excavator 100 and the power supply vehicle 130. As shown in FIG. 4, the power supply wheel 130 is located behind the excavator 100. The power supply vehicle 130 includes a power supply device having a battery 131 and an inverter 132. The battery 131 is a power storage device including a plurality of lithium ion secondary batteries, and is configured to be easily detached from the power supply vehicle 130. The battery 131 and the inverter 132 are connected by a detachable cable 141, and the DC power of the battery 131 is supplied to the inverter 132 through the cable 141. The inverter 132 converts the DC power of the battery 131 into three-phase AC power using a switching circuit (not shown) configured by a transistor provided therein, and supplies the electric motor 111 with power.

  The electric power supplied from the inverter 132 is supplied to the excavator 100 via the cable 140. The cable 140 is guided by a cable stand 142 on the swing body 105 of the excavator 100 and connected to a connector 143 of the cable stand 142. The cable stand 142 includes a rotating shaft 142a that can rotate with respect to the revolving body 105, and a guide member 142b that extends in the horizontal direction from the upper end of the rotating shaft 142a. The rotation shaft 142a is held by the revolving body 105 via a bearing 142c. The bearing 142 c has an inner peripheral side fixed to the rotating shaft 142 a and an outer peripheral side fixed to the swing body 105.

  The guide member 142b holds one end of the cable 140, and the cable 140 hangs from the tip of the guide member 142b toward the ground. When the turning body 105 rotates to one side, the cable stand 142 rotates about the rotation shaft 142a in the direction opposite to the turning direction by the action of the gravity of the cable 140. For this reason, compared with the case where there is no cable stand 142, the movement amount of the cable 140 can be reduced.

  The cable 140 has a configuration in which a plurality of single wires made of one wiring are included in the cable 140 so that three-phase AC power can be supplied. The hydraulic excavator 100 according to the present embodiment is configured to selectively connect a commercial power source (not shown) and the power supply vehicle 130.

  FIG. 5 is a block diagram showing a configuration of the electric work assistance system. As illustrated in FIG. 5A, the power supply vehicle 130 includes a controller 160, a camera 170 that is a photographing device, a cable winding device 180, and a tension detection device 190 that detects the tension of the cable 140. .

  The controller 160 is configured to include an arithmetic processing unit having a CPU and a storage device such as ROM and RAM, and other peripheral circuits. An imaging signal from the camera 170 and a tension signal from the tension detector 190 are input to the controller 160. As will be described later, the controller 160 controls the cable winding device 180 on the basis of the imaging signal and the tension signal, and the information terminal 200 and the field worker and / or the operator who is disposed in the cab 104 of the excavator 100. Alternatively, information such as an alarm is transmitted to the information terminal 300 used by the site supervisor.

  The camera 170 includes an imaging optical system, an imaging element, and the like. The imaging element is, for example, a CMOS or CCD, and captures a subject image formed by the imaging optical system and transmits an imaging signal to the controller 160. The camera 170 is disposed at a position where the cable 140 and the excavator 100 can be always photographed.

  The cable winding device 180 includes a drum (not shown) around which the cable 140 is wound, and a motor (not shown) that drives the drum. When a certain amount of tension acts on the cable 140, the cable 140 is unwound from the drum. The cable winding device 180 can wind the cable 140 with the drum by rotating the drum (not shown) with a motor (not shown). In the cable winding device 180, when a drive signal (winding signal) output from the controller 160 is input, a motor (not shown) is rotationally driven. In the cable winding device 180, the motor (not shown) stops when the stop signal output from the controller 160 is input. The controller 160 outputs a drive signal (winding signal) for the cable winding device 180 when both a first winding condition and a second winding condition described later are satisfied, and a first winding stop condition described later. Alternatively, when the second winding stop condition is satisfied, a stop signal of the cable winding device 180 is output.

  The controller 160 functionally includes a condition determination unit 161, a distance calculation unit 165, a distance threshold setting unit 166, and an alarm transmission unit 167. The distance calculation unit 165 calculates the shortest distance X between the cable 140 and the traveling body 102 of the excavator 100. A method of calculating the shortest distance X by the distance calculation unit 165 will be described later.

  The condition determination unit 161 determines whether the tension F1 detected by the tension detector 190 is less than the first threshold value Fa. The condition determination unit 161 determines that the first winding condition is not satisfied when the tension F1 is equal to or greater than the first threshold value Fa. The condition determination unit 161 determines that the first winding condition is satisfied when the tension F1 is less than the first threshold value Fa. The first threshold value Fa is determined by the movement of the excavator 100 and / or the power supply vehicle 130 so that the distance between the excavator 100 and the power supply vehicle 130 is increased, or the rotation of the excavator 100. 140 is a threshold value for determining that the cable winding device 180 has been fed out. In the present embodiment, when the tension F1 acting on the cable 140 is equal to or greater than the first threshold value Fa, the cable 140 is unwound from the drum. The first threshold value Fa is stored in advance in the storage device of the controller 160.

  The condition determination unit 161 determines whether or not the tension F1 is less than the alarm tension threshold Fmax. The condition determination unit 161 determines that the tension alarm condition is not satisfied when the tension F1 is less than the alarm tension threshold Fmax, and the tension alarm condition is satisfied when the tension F1 is equal to or greater than the alarm tension threshold Fmax. It is determined that The alarm tension threshold value Fmax is stored in the storage device of the controller 160 in advance. The alarm tension threshold value Fmax is a threshold value set to prevent the cable 140 from being damaged, and is set to a value equal to or lower than the allowable tension of the cable 140.

  When the first winding condition is satisfied, the condition determination unit 161 determines whether or not the shortest distance X calculated by the distance calculation unit 165 is less than the distance threshold La. The condition determination unit 161 determines that the second winding condition is not satisfied when the shortest distance X is equal to or greater than the distance threshold La, and the second winding condition is determined when the shortest distance X is less than the distance threshold La. It is determined that it has been established. The distance threshold value La is a threshold value for determining that the distance between the excavator 100 and the cable 140 is near and causing the cable winding device 180 to perform the winding operation of the cable 140. The distance threshold value La is stored in the storage device of the controller 160 in advance. It is remembered.

  The distance threshold setting unit 166 sets the shortest distance X as the distance threshold Xc when the second winding condition is satisfied. The distance threshold value Xc is set as a threshold value for determining whether or not the shortest distance X has increased after the second winding condition is satisfied, and is stored in the storage device of the controller 160. The distance threshold value Xc is set for each predetermined control period. That is, when the shortest distance X increases, the distance threshold value Xc also increases.

  The condition determination unit 161 determines whether or not the shortest distance X calculated by the distance calculation unit 165 is less than the distance threshold value Xc. When the shortest distance X is less than the distance threshold Xc, that is, when it is determined that the shortest distance X is decreasing, the condition determination unit 161 assumes that the risk that the crawler 103 steps on the cable 140 increases due to rewinding. Then, it is determined that the first winding stop condition is satisfied. When the shortest distance X is equal to or greater than the distance threshold value Xc, the condition determination unit 161 determines that the first winding stop condition is not satisfied, assuming that the risk of the crawler 103 stepping on the cable 140 has decreased due to rewinding.

  When the first winding stop condition is not satisfied, the condition determination unit 161 determines whether the tension F1 detected by the tension detector 190 is equal to or greater than the second threshold value Fb. The condition determination unit 161 determines that the second winding stop condition is not satisfied when the tension F1 is less than the second threshold Fb, and stops the second winding when the tension F1 is equal to or greater than the second threshold Fb. It is determined that the condition is satisfied. The second threshold value Fb is a threshold value that is less than the first threshold value Fa and for determining that the bent cable 140 is arranged in a straight line, and is stored in the storage device of the controller 160 in advance.

  The condition determination unit 161 determines whether or not the shortest distance X calculated by the distance calculation unit 165 is less than the alarm distance threshold value Xmin. The condition determination unit 161 determines that the distance alarm condition is not satisfied when the shortest distance X is greater than or equal to the alarm distance threshold Xmin, and if the shortest distance X is less than the alarm distance threshold Xmin, the distance alarm condition is It is determined that it has been established. The alarm distance threshold value Xmin is a threshold value set to alert the driver before the cable 140 comes into contact with the traveling body 102, that is, before the cable 140 becomes an underlay of the traveling body 102. The alarm distance threshold value Xmin is stored in advance in the storage device of the controller 160.

  When the tension alarm condition is satisfied, the alarm transmission unit 167 transmits overload information (alarm signal) indicating that an overload is acting on the cable 140 to the information terminal 200 and the information terminal 300. When the information terminal 200 and the information terminal 300 receive the overload information, the information terminal 200 and the information terminal 300 notify that an overload is generated by voice through a speaker (not shown), and an overload occurs on the display device (not shown). A display image showing that the user is doing is displayed.

  When the distance alarm condition is satisfied, the alarm transmission unit 167 transmits approach information (alarm signal) indicating that the cable 140 and the crawler 103 of the excavator 100 are close to the information terminal 200 and the information terminal 300. When the information terminal 200 and the information terminal 300 receive the approach information, the cable 140 and the crawler 103 of the excavator 100 are approached by voice via a speaker (not shown), and the cable 140 can be stepped on by the crawler 103. Informs that it is high. When receiving the approach information, the information terminal 200 and the information terminal 300 display a display image indicating that the cable 140 and the crawler 103 of the excavator 100 are approaching each other on a display device (not shown).

  A method for determining the shortest distance X by the distance calculation unit 165 will be described with reference to FIG. 6A is a schematic plan view showing the positional relationship between the excavator 100 and the power supply wheel 130. FIG. 6B shows symbol marks M1 and M2 painted on the rear surface of the counterweight 101 of the excavator 100. FIG. It is a schematic diagram shown. FIG. 6C is a schematic diagram illustrating an image captured by the camera 170. FIG. 6D is a diagram for explaining how to obtain the length per pixel, and FIG. 6E is a diagram for explaining how to obtain the shortest distance X between the crawler 103 and the cable 140.

  In the present embodiment, it is assumed that the cable 140 is placed on the same plane as the traveling surface of the excavator 100, and the shortest distance between the cable 140 and the crawler 103 of the traveling body 102 in the excavator 100 is as follows. X is calculated.

  As shown in FIG. 5B, the distance calculation unit 165 functionally includes a unit distance calculation unit 165a and a shortest distance calculation unit 165b. When the excavator 100 is photographed from diagonally right behind the excavator 100 as shown in FIG. 6 (a), the excavator 100 placed on the flat ground is shown in the image G1 as shown in FIG. 6 (c). It is tilted diagonally. In addition, in FIG.6 (c), the flat ground is shown with the broken line.

The unit distance calculation unit 165a identifies the crawler 103 from the image G1 captured by the camera 170, as shown in FIG. The unit distance calculation unit 165a sets the horizontal width (actual size) of the crawler 103 stored in advance in the storage device as the specific section L1. As shown in FIG. 6D, the unit distance calculation unit 165a uses the number of pixels px in the x direction (horizontal direction) and the number of pixels py in the y direction (vertical direction) on the image representing the specific section L1. A length Kp per pixel (unit pixel) is calculated. The length Kp per pixel is expressed by the following equation (1).

The shortest distance calculation unit 165b specifies a pair of left and right crawlers 103 and a cable 140. The shortest distance calculation unit 165b calculates the shortest distance ZR between the grounding surface of the right crawler 103 and the cable 140, as shown in FIG. The shortest distance ZR is expressed by the following equation (2) using the number of pixels pxr in the x direction (horizontal direction) and the number of pixels pyr in the y direction (vertical direction) on the image (virtual line segment) representing the shortest distance ZR. expressed.

Similarly, the shortest distance calculation unit 165b calculates the shortest distance ZL between the grounding surface of the left crawler 103 and the cable 140. The shortest distance ZL is expressed by the following equation (3) using the number of pixels pxl in the x direction (horizontal direction) and the number of pixels pyl in the y direction (vertical direction) on the image (virtual line segment) representing the shortest distance ZL. expressed.

  The shortest distance calculation unit 165b sets the shorter one of the shortest distance ZR and the shortest distance ZL as the shortest distance X, and stores it in the storage device of the controller 160. The calculation process of the shortest distance X is calculated every predetermined control cycle.

  In addition, although the example which calculates | requires the shortest distance X of the cable 140 and the crawler 103 by specifying the crawler 103 as a symbol and making the horizontal width of the crawler 103 into the specific area L1 was demonstrated, you may utilize another symbol. For example, as shown in FIG. 6B, a character string “TEST MARK” is formed on the rear surface of the counterweight 101 as a symbol mark M1 by painting. Information representing the actual shape of the character string “TEST MARK” is stored in advance in the storage device of the controller 160, and the symbol mark M1 can be specified by the unit distance calculation unit 165a. In the storage device of the controller 160, the dimension (actual size) of the line segment connecting the center of “T” that is the first character of the character string and the center of “K” that is the last character of the character string is the specific section L2. Is remembered as Accordingly, the shortest distance X can be obtained by using the specific section L2 instead of the specific section L1 in the above-described formulas (1) to (3).

  As another example, as shown in FIG. 6B, a pair of rectangular symbol marks M2 may be formed, and the dimension between the pair of symbol marks M2 may be used as the specific section L3. The dimension (actual dimension) between the pair of symbol marks M2 is stored in the storage device of the controller 160 in advance. In this case as well, the shortest distance X can be obtained by using the specific section L3 instead of the specific section L1 in the above formulas (1) to (3).

  FIG. 7 is a flowchart showing the contents of cable winding drive processing and overload warning transmission processing by the controller 160, and FIG. 14 is a flowchart showing an example of approach warning transmission processing in the controller 160. Each of the processes shown in the flowcharts of FIGS. 7 and 14 is started by turning on an ignition switch (not shown), for example, and is repeatedly executed after an initial setting (not shown) is performed. The process shown in FIG. 14 is a process performed in a loop different from the process of FIG. 7, and the shortest distance X between the crawler 103 and the cable 140 is constantly monitored, and the shortest distance X is less than the alarm distance threshold value Xmin. Sometimes it is a process to send an alarm.

(Cable winding drive processing and overload alarm transmission processing)
As shown in FIG. 7, in step S101, the controller 160 acquires the tension F1 that is information detected by the tension detector 190, and proceeds to step S106. In step S106, the controller 160 determines whether or not the tension F1 acquired in step S101 is less than the first threshold value Fa. If a negative determination is made in step S106, the process proceeds to step S111, and if a positive determination is made in step S106, the process proceeds to step S136.

  In step S111, the controller 160 determines whether or not the tension F1 acquired in step S101 is less than the alarm tension threshold Fmax. If an affirmative determination is made in step S111, the process returns to step S101, and if a negative determination is made in step S111, the process proceeds to step S126.

  In step S126, the controller 160 transmits overload information (alarm signal) to the information terminal 200 and the information terminal 300, and ends the process shown in FIG.

  When an affirmative determination is made in step S106 and the process proceeds to step S136, in step S136, the controller 160 calculates the shortest distance X between the crawler 103 and the cable 140 from the image G1 captured by the camera 170, and the process proceeds to step S141. move on.

  In step S141, the controller 160 determines whether or not the shortest distance X is less than the distance threshold La. If an affirmative determination is made in step S141, the process proceeds to step S146, and if a negative determination is made in step S141, the process returns to step S101.

  In step S146, the controller 160 sets the shortest distance X calculated in step S136 as the distance threshold value Xc, stores it in the storage device, and proceeds to step S151.

  In step S151, the controller 160 outputs a rotation signal (winding signal) to a motor (not shown) of the cable winding device 180, and the cable winding device 180 winds the cable 140 (rotation operation in the collecting direction). And the process proceeds to step S161.

  In step S161, the controller 160 calculates the shortest distance X between the crawler 103 and the cable 140 from the image G1 photographed by the camera 170, and proceeds to step S166.

  In step S166, the controller 160 determines whether or not the shortest distance X is less than the distance threshold value Xc. If an affirmative determination is made in step S166, the process proceeds to step S171. If a negative determination is made in step S166, the process proceeds to step S153.

  In step S171, the controller 160 outputs a stop signal to a motor (not shown) of the cable winding device 180, stops the winding operation of the cable 140, and returns to step 101.

  In step S153, the controller 160 acquires the tension F1, which is information detected by the tension detector 190, and proceeds to step S156. In step S156, the controller 160 determines whether or not the tension F1 acquired in step S153 is greater than or equal to the second threshold value Fb. If a negative determination is made in step S156, the process returns to step S146, and if a positive determination is made in step S156, the process proceeds to step S158.

  In step S158, the controller 160 outputs a stop signal to the motor (not shown) of the cable winding device 180, stops the winding operation of the cable 140, and returns to step 101.

(Access warning transmission processing)
The approach warning transmission process shown in FIG. 14 is repeatedly executed at a predetermined control cycle. That is, in this embodiment, as shown in FIG. 14, the comparison between the shortest distance X and the alarm distance threshold value Xmin is always performed. In step S180, the controller 160 calculates the shortest distance X between the crawler 103 and the cable 140 from the image G1 photographed by the camera 170, and proceeds to step S181.

  In step S181, the controller 160 determines whether or not the shortest distance X calculated in step S180 is less than the alarm distance threshold value Xmin. If a positive determination is made in step S181, the process proceeds to step S186, and if a negative determination is made in step S181, the process returns to step S180.

  In step S186, the controller 160 transmits approach information (alarm signal) to the information terminal 200 and the information terminal 300, and ends the process shown in FIG.

  The operation of the present embodiment is summarized as follows. FIG. 8 is a schematic plan view illustrating an example of a change in relative position between the excavator 100 and the power supply vehicle 130. When the driver turns on the ignition switch, the vehicle is activated. As shown in FIG. 8A, the tension F1 of the cable 140 is less than the first threshold Fa when the cable 140 is bent out on the ground without being drawn out. At this time, the controller 160 calculates the shortest distance X between the crawler 103 and the cable 140 at a predetermined control cycle and compares it with the distance threshold La to determine whether the shortest distance X is less than the distance threshold La. Monitoring is in progress (Yes in S106 → S136 → No in S141).

  When the excavator 100 moves or turns from the state shown in FIG. 8A and the tension F1 of the cable 140 becomes equal to or greater than the first threshold value Fa, the cable 140 is removed from the drum of the cable winding device 180. It is fed out (rotation in the cable winding direction). At this time, the controller 160 is constantly monitoring whether an excessive load is applied to the cable 140 (No in S106, Yes in S111).

  When the excavator 100 has a fast moving speed and a turning speed and a tension F1 greater than the alarm tension threshold Fmax is applied to the cable 140, information used by the information terminal 200 in the cab 104, field workers, and field supervisors. A speaker (not shown) and a display device (not shown) constituting the terminal 300 notify that the cable 140 is overloaded (No in S111, S126).

  As shown in FIG. 8B and FIG. 8C, when the excavator 100 completes the movement or turning operation and the tension F1 acting on the cable 140 becomes less than the first threshold value Fa, the feeding operation of the cable 140 is performed. It stops, and it will be in the state which always monitors whether the shortest distance X will become less than the distance threshold value La again (Yes in S106-> S136-> No in S141).

  When the excavator 100 moves or turns, if the shortest distance X between the cable 140 and the crawler 103 is less than the distance threshold La, the cable winding device 180 performs the winding operation of the cable 140 ( Yes in S141).

  During the winding operation of the cable 140, the controller 160 calculates the shortest distance X between the crawler 103 and the cable 140 at a predetermined control cycle and compares it with the distance threshold value Xc, so that the shortest distance X becomes less than the distance threshold value Xc. It is in a state of constantly monitoring whether or not there is any (No in S151 → S161 → S166). The distance threshold Xc is constantly updated (No in S161 → S166, No → S156, No → S146, and the distance threshold Xc is set to the shortest distance X calculated in S161). When it is determined that the shortest distance X between the cable 140 and the crawler 103 is decreased, the winding operation of the cable 140 is stopped (Yes in S166).

  During the winding operation of the cable 140, the controller 160 acquires the tension F1 at a predetermined control cycle and compares it with the second threshold value Fb (S153 → S156). The winding operation of the cable 140 is ended when the cable 140 placed on the ground is bent and the tension F1 acting on the cable 140 becomes equal to or greater than the second threshold Fb (Yes in S156).

  In the present embodiment, the controller 160 is constantly monitoring whether the shortest distance X is shorter than the alarm distance threshold value Xmin (No in S180 → S181 in FIG. 14).

  When the movement (turning or turning) is performed so that the cable 140 and the crawler 103 approach each other and the shortest distance X becomes shorter than the alarm distance threshold value Xmin, the information terminal 200 in the cab 104, the field worker, the field supervisor An alarm is output by a speaker (not shown) and a display device (not shown) that constitute the information terminal 300 used by the person (Yes in S181). For example, the fact that the cable 140 and the crawler 103 are close to each other and the cable 140 may be stepped on by the crawler 103 due to the continuation of the operation by the driver is indicated by a voice or a display image based on the voice or the display image. Inform workers and field supervisors.

According to the embodiment described above, the following operational effects can be obtained.
(1) The hydraulic excavator 100 includes a turning frame 105f having a common support base 125 that supports an electric motor 111 that drives each of the traveling body 102, the turning body 105, and the front work device 110. The shared support stand 125 is configured to support the engine 191 instead of the electric motor 111. Since one hydraulic excavator 100 can support each of the electric motor 111 and the engine 191, a drive source corresponding to an energy source that can be obtained at low cost is selected in the construction site area, thereby reducing the work cost. Can be planned.

(2) When the electric motor 111 is supported by the shared support base 125, the electric motor 111 is supported via the motor bracket 121. When the engine 191 is supported by the shared support base 125, the engine 191 is supported via the engine bracket 129. When supporting either one of the engine 191 and the electric motor 111 on the shared support base 125, it is only necessary to prepare a support bracket for the drive source to be supported, thereby suppressing an increase in cost due to common parts. it can.

(3) The controller 160 determines whether or not the shortest distance X between the crawler 103 of the excavator 100 and the cable 140 is smaller than the alarm distance threshold value Xmin based on the image taken by the camera 170. When it is determined that the shortest distance X is smaller than the alarm distance threshold value Xmin, the controller 160 transmits approach information (alarm) to the information terminal 200 and the information terminal 300. As a result, the information terminal 200 and the information terminal 300 indicate that the cable 140 is close to the crawler 103 and that the cable 140 is likely to be stepped on by the crawler 103. You can inform on-site supervisors. Before the cable 140 is stepped on by the crawler 103, the driver can stop the work and take appropriate measures such as the movement of the power supply car 130 and the cable 140, so that the cable 140 is stepped on by the crawler 103. Can be prevented. Further, when the approach information (alarm) is not issued, there is no possibility that the cable 140 is stepped on by the crawler 103, and therefore it is not necessary to move the power supply vehicle 130 frequently. That is, according to the present embodiment, the movement of the power supply vehicle 130 can be minimized, so that the work efficiency can be improved. Furthermore, when the cable 140 approaches the crawler 103, it is possible to notify the driver, the site worker, the site supervisor, etc., so that the burden on the driver can be reduced. As a result, since the driver can concentrate on the work, the work efficiency can be improved.

(4) The excavator 100 includes a symbol for distance calculation. For example, the crawler 103 or the symbol marks M1 and M2 can be used as the symbol. The controller 160 determines the distance per pixel constituting the image G1 based on the symbol image in the image G1 photographed by the camera 170. The controller 160 determines the distance between the crawler 103 of the excavator 100 and the cable 140 based on the distance per pixel and the image of the crawler 103 of the excavator 100 and the image of the cable 140 in the image G1 taken by the camera 170. To decide. Thereby, the distance between the crawler 103 and the cable 140 can be determined in real time.

-Second Embodiment-
With reference to FIG. 9, the electric work assistance system which concerns on 2nd Embodiment is demonstrated. In the figure, the same or corresponding parts as those in the first embodiment are denoted by the same reference numerals, and differences will mainly be described. FIG. 9 is a schematic plan view showing the hydraulic excavator 100, the power supply car 130, and the cable 240 that constitute the electric work assist system according to the second embodiment.

  The electric work assistance system of the second embodiment has the same configuration as the electric work assistance system of the first embodiment. The electric work assistance system of the second embodiment is different from the first embodiment in that a plurality of marks 244 are attached to the cable 240. The cable 240 is provided with marks 244 at equal intervals along the longitudinal direction of the cable 240. The mark 244 is formed of a paint having a special color having a fluorescent color or a metallic luster, for example.

  In the second embodiment, the unit distance calculation unit 165a (see FIG. 5B) sets the dimension between the adjacent marks 244 from the image G1 captured by the camera 170 as the specific section L4. The storage device of the controller 160 stores the size (actual size) between adjacent marks 244. Similarly, in the second embodiment, the shortest distance X can be obtained by using the specific section L4 instead of the specific section L1 in the above formulas (1) to (3).

According to such 2nd Embodiment, in addition to the effect similar to 1st Embodiment, there exists the following effect.
(5) By configuring the mark 244 with a special color having a fluorescent color or metallic luster, it is easy to recognize the cable 240 from various objects existing at a construction site or the like. In addition, the cable 240 can be easily recognized even when the construction site is in a dark environment such as at night.

-Third embodiment-
With reference to Fig.10 (a), the electrically-driven work assistance system which concerns on 3rd Embodiment is demonstrated. In the figure, the same or corresponding parts as those in the first embodiment are denoted by the same reference numerals, and differences will mainly be described. FIG. 10A is a flowchart illustrating an example of alarm transmission processing in the controller according to the third embodiment. In the third embodiment, the process shown in FIG. 10A is executed in addition to the process described in the first embodiment (see FIG. 7).

  As shown in FIG. 10A, in step S302, the controller 160 calculates the length Lc of the cable 140 from the captured image G1. The calculation method of the length Lc of the cable 140 is the same as the calculation method of the shortest distance X between the cable 140 and the crawler 103 described above. That is, the controller 160 calculates the length Kp per pixel from the actual size of the symbol such as the crawler 103 and the photographed symbol image. The controller 160 obtains the length Lc of the cable 140 by multiplying the number of pixels of the image constituting the photographed cable 140 by Kp.

  When the cable length Lc is calculated in step S302, the process proceeds to step S308. In step S308, the controller 160 determines whether or not the cable length Lc is greater than or equal to the length threshold Lc1. If an affirmative determination is made in step S308, the process proceeds to step S314. If a negative determination is made in step S308, the process returns to step S302.

  In step S314, the controller 160 transmits an alarm signal to the information terminal 200 and the information terminal 300, and ends the process illustrated in FIG.

According to such 3rd Embodiment, in addition to the effect similar to 1st Embodiment, there exists the following effect.
(6) The controller 160 determines the length Lc of the cable 140 based on the image G1 photographed by the camera 170. When the length Lc of the cable 140 is longer than the predetermined length Lc1, the controller 160 sends the predetermined information to the information terminal. 200, 300. With such a configuration, the cable 140 can be prevented from being pulled out more than necessary. Furthermore, since it is possible to prevent excessive tension from acting on the cable 140 when the cable 140 is pulled out to the maximum length, the cable 140, the cable stand 142, and the like can be prevented from being damaged.

-Fourth embodiment-
With reference to FIG.10 (b), the electrically-driven work assistance system which concerns on 4th Embodiment is demonstrated. In the figure, the same or corresponding parts as those in the first embodiment are denoted by the same reference numerals, and differences will mainly be described. FIG. 10B is a flowchart illustrating an example of alarm transmission processing in the controller according to the fourth embodiment. In the fourth embodiment, the process shown in FIG. 10B is executed in addition to the process described in the first embodiment (see FIG. 7).

  As shown in FIG. 10B, in step 402, the controller 160 calculates the shortest distance d between the excavator 100 and the power supply vehicle 130 from the captured image G1. The calculation method of the shortest distance d is the same as the calculation method of the shortest distance X between the cable 140 and the crawler 103 described above. That is, the controller 160 calculates the length Kp per pixel from the actual size of the symbol such as the crawler 103 and the photographed symbol image. The controller 160 connects the photographed excavator 100 and the power supply vehicle 130 with a straight line, and obtains the shortest distance d by multiplying the number of pixels of the image constituting the connected line segment by Kp.

  When the shortest distance d is calculated in step S402, the process proceeds to step S408. In step S408, the controller 160 determines whether or not the shortest distance d is less than the length threshold value d1. If a positive determination is made in step S408, the process proceeds to step S414, and if a negative determination is made in step S408, the process returns to step S402.

  In step S414, the controller 160 transmits an alarm signal to the information terminal 200 and the information terminal 300, and ends the process illustrated in FIG.

According to such 4th Embodiment, in addition to the effect similar to 1st Embodiment, there exists the following effect.
(7) The controller 160 determines the shortest distance d between the excavator 100 and the power supply vehicle 130, and when the shortest distance d between the excavator 100 and the power supply vehicle 130 is shorter than the predetermined distance d1, the controller 160 transmits the predetermined information to the information terminal. 200, 300. With such a configuration, contact between the excavator 100 and the power supply vehicle 130 can be avoided.

-Fifth embodiment-
With reference to FIG. 11 and FIG. 12, the electric work assistance system which concerns on 5th Embodiment is demonstrated. In the figure, the same or corresponding parts as those in the first embodiment are denoted by the same reference numerals, and differences will mainly be described. FIG. 11 is a flowchart illustrating an example of cable winding drive processing in the controller according to the fifth embodiment. In the fifth embodiment, the process shown in FIG. 11 is executed in addition to the process described in the first embodiment (see FIG. 7).

  As shown in FIG. 11, in step S521, the controller 160 identifies the cable 140 placed on the ground from the photographed image G1, and proceeds to step S525. In step S525, the controller 160 determines whether or not the image forming the cable 140 has a shape stored in advance in the storage device. In the present embodiment, U-shaped and O-shaped shapes are stored in advance in the storage device of the controller 160. The controller 160 compares the shape (U shape and O shape) stored in the storage device with the shape of the image of the photographed cable 140.

  FIG. 12 is a schematic diagram illustrating an example of an arrangement state of the cable 140. If the cable 140 is arranged in a U-shape as shown in FIG. 12A, or if the cable 140 is arranged in an O-shape as shown in FIG. 12B, an affirmative determination is made in step S525. Then, the process proceeds to step S527.

  In step S527, the controller 160 outputs a rotation signal (winding signal) to a motor (not shown) of the cable winding device 180 to cause the cable winding device 180 to perform the winding operation of the cable 140, and then proceeds to step S521. Return.

  When the cable 140 is wound up and the arrangement shape of the cable 140 is not U-shaped or O-shaped, a negative determination is made in step S525, and the process proceeds to step S529. In step S529, the controller 160 outputs a stop signal to a motor (not shown) of the cable winding device 180, stops the winding operation of the cable 140, and returns to step 521.

According to such 5th Embodiment, in addition to the effect similar to 1st Embodiment, there exists the following effect.
(8) The controller 160 estimates the length of the cable 140 by specifying the shape of the cable 140 based on the image captured by the camera 170. When the controller 160 detects a shape (for example, a U shape or an O shape) representing that the length Lc of the cable 140 is longer than the predetermined length Lc1, the controller 160 performs the winding operation of the cable 140 by the cable winding device 180. Run. With such a configuration, the cable 140 can be prevented from being pulled out more than necessary. Furthermore, since it is possible to prevent excessive tension from acting on the cable 140 when the cable 140 is pulled out to the maximum length, the cable 140, the cable stand 142, and the like can be prevented from being damaged.

The following modifications are also within the scope of the present invention, and one or a plurality of modifications can be combined with the above-described embodiment.
(Modification 1)
In the above-described embodiment, the example in which the image G1 captured by the camera 170 is used to calculate the shortest distance X between the crawler 103 and the cable 140 has been described, but the present invention is not limited to this. For example, the shortest distance X between the crawler 103 and the cable 140 may be determined by a distance measuring device using a laser. In this case, the distance between the crawler 103 and the cable 140 is measured by scanning the laser in a range near the traveling body 102 so that the traveling body 102 of the excavator 100 and the position of the cable 140 near the traveling body 102 can be confirmed. To do.

(Modification 2)
In the above-described embodiment, the example in which the shortest distance X between the crawler 103 and the cable 140 is calculated based on the image G1 photographed by the camera 170 attached to the power supply car 130 has been described. It is not limited. As shown in FIG. 13, a camera 370 may be provided on the swing body 105 of the excavator 100, and the shortest distance X between the crawler 103 and the cable 140 may be calculated based on an image captured by the camera 370. Compared with the first embodiment, since the correlation between the crawler 103 and the cable 140 can be monitored at a position closer to the crawler 103 and the cable 140, the calculation of the shortest distance X can be performed with higher accuracy. It should be noted that a camera is provided in each of the power supply vehicle 130 and the hydraulic excavator 100, and the average value of the shortest distance calculated based on the images photographed by both is compared with a predetermined threshold (La or Xc). Good.

(Modification 3)
In the third embodiment, when the length Lc of the cable 140 is calculated based on the image G1 photographed by the camera 170 and it is determined that the length Lc of the cable 140 is longer than the predetermined length Lc1. Although an example of transmitting an alarm has been described, the present invention is not limited to this. For example, when the mark is attached to the cable 140 and the mark is detected in the image G1 photographed by the camera 170, it is determined that the length Lc of the cable 140 is longer than the predetermined length Lc1, and an alarm is transmitted. May be. Further, the number of rotations of the drum is detected by a potentiometer or the like without using the camera 170, and based on the detected number of rotations, it is determined that the length Lc of the cable 140 is longer than the predetermined length Lc1, and an alarm is transmitted. May be.

(Modification 4)
In the third embodiment, the example in which the alarm is transmitted when it is determined that the length Lc of the cable 140 is longer than the predetermined length Lc1 has been described, but instead of the alarm transmission or with the alarm transmission. The cable winding device 180 may execute the winding operation of the cable 140. That is, when it is determined that the length Lc of the cable 140 is longer than the predetermined length Lc1 by a method as shown in Modification 3, the cable winding device 180 may perform the winding operation of the cable 140.

(Modification 5)
In the above-described embodiment, the example in which the inverter 132 and the battery 131 are mounted on one vehicle (power supply car 130) has been described, but the present invention is not limited to this. As shown in FIG. 15, the inverter vehicle 630A on which the inverter 132 is mounted and the battery vehicle 630B on which the battery 131 is mounted may be separated. In this case, inverter vehicle 630A and battery vehicle 630B are detachably connected to connecting portion 639. The inverter 132 and the battery 131 are connected by a detachable cable 141.

  The controller 160 monitors the charge amount of the battery 131, and transmits information indicating the charge amount decrease to the information terminals 200 and 300 when the charge amount of the battery 131 mounted on the battery vehicle 630B decreases. As a result, the battery vehicle 630B on which the battery 131 having a reduced charge amount is mounted can be replaced with another battery vehicle on which a charged battery is mounted, so that continuous work can be performed.

(Modification 6)
In the above-described embodiment, the example in which the controller 160 is mounted on the power supply vehicle 130 has been described, but the present invention is not limited to this. The control device of the excavator 100 may have the function of the controller 160. In this case, information from the camera 170 mounted on the power supply vehicle 130 may be transmitted to the control device of the excavator 100. The control device transmits an alarm signal to the information terminal 300 and transmits a winding signal to the cable winding device 180.

(Modification 7)
In the above-described embodiment, the cable winding device 180 has been described with respect to an example in which only winding is performed by driving a motor. However, the present invention is not limited to this. The feeding may be performed by driving the motor.

(Modification 8)
The camera 170 is not limited to the case where one power supply car 130 is provided, and a plurality of cameras 170 may be provided. Similarly, the camera 370 is not limited to the case where one camera is provided in the excavator 100, and a plurality of cameras 370 may be provided.

(Modification 9)
In the above-described embodiment, the example in which the present invention is applied to the hydraulic excavator 100 has been described. However, the present invention is not limited to this, and can be applied to various construction machines such as a wheel excavator and a crane.

  Although various embodiments and modifications have been described above, the present invention is not limited to these contents. Other embodiments conceivable within the scope of the technical idea of the present invention are also included in the scope of the present invention.

DESCRIPTION OF SYMBOLS 100 Hydraulic excavator (construction machine), 102 traveling body, 103 crawler (symbol for distance calculation), 105 revolving body, 105f revolving frame (frame), 110 front working device (working device), 111 electric motor, 121 bracket for motor (Support bracket for electric motor), 125 shared support base (support part), 129 bracket for engine (support bracket for engine), 130 power supply car, 131 battery (power supply device), 132 inverter (power supply device), 140 cable , 160 controller (control device), 170 camera (imaging device), 180 cable winding device, 191 engine, 200 information terminal, 240 cable, 244 mark (symbol for distance calculation), 300 information terminal, 370 camera (imaging device) )

Claims (6)

A traveling body, a revolving body provided on the traveling body, a working device provided on the revolving body, and pressure oil for driving each of the traveling body, the revolving body, and the working device are supplied. A hydraulic pump, and a construction machine including an electric motor that drives the hydraulic pump;
A power supply vehicle including a power supply device that supplies electric power to the electric motor mounted on the construction machine via a cable;
A photographing device provided in at least one of the construction machine and the power supply vehicle;
A control device for determining whether a distance between the construction machine and the cable is smaller than a predetermined distance based on an image photographed by the photographing device;
The electric control system, wherein the control device transmits predetermined information to an information terminal when it is determined that a distance between the construction machine and the cable is smaller than the predetermined distance. In the electric work assistance system according to claim 1,
Either of the construction machine and the cable is provided with a symbol for distance calculation,
The control device determines a distance per pixel constituting an image photographed by the photographing device based on an image of the symbol photographed by the photographing device, and determines the distance per pixel and the photographing device. The electric work assistance system which determines the distance of the said construction machine and the said cable based on the image | photographed said construction machine and the said cable. In the electric work assistance system according to claim 1,
The control device determines the length of the cable based on an image photographed by the photographing device, and transmits predetermined information to the information terminal when the length of the cable is longer than a predetermined length. Work assistance system. In the electric work assistance system according to claim 1,
The control device determines a distance between the construction machine and the power supply vehicle, and transmits predetermined information to the information terminal when the distance between the construction machine and the power supply vehicle is shorter than a predetermined distance. system. In the electric work assistance system according to claim 1,
The power supply vehicle includes a cable winding device capable of winding the cable,
The control device determines a length of the cable based on an image photographed by the photographing device, and winds the cable to the cable winding device when the length of the cable is longer than a predetermined length. An electric work assistance system that performs operations. In the electric work assistance system according to claim 1,
The construction machine includes a frame having a support portion that supports the electric motor,
The support portion is configured to be able to support an engine instead of the electric motor,
When the electric motor is supported by the support portion, the electric motor is supported via a support bracket for the electric motor,
When the engine is supported by the support portion, the electric work assistance system in which the engine is supported via a support bracket for the engine.

Images