JPH0230906B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a vehicle body leveling device for a work vehicle having outriggers, and more specifically, the present invention relates to a vehicle body leveling device for a work vehicle having outriggers. The present invention relates to a vehicle body leveling device that can horizontally set a vehicle body by varying the amounts. This is used in fields where the vehicle body is automatically set horizontally using outriggers even on sloped terrain, so that the range of possible displacement of work equipment mounted on the vehicle body is equal to that on level ground.

[Conventional technology]

Aerial work vehicles that have a gondola at the end of a boom that can extend and contract, raise and lower, and swivel freely, and crane trucks that have cranes that can lower and lower and swivel freely, are equipped with outriggers on the front, rear, left, and right sides of the vehicle body 1, as shown in Figure 1a. 2A~
2D is installed so that the weight of the boom 3, gondola 4, workers, crane, and their suspended objects can be supported over as wide an operating range as possible. That is, each outrigger 2A to 2D
Each has an overhanging jack and a lifting jack. After the former is extended to the left and right in the vehicle width direction, the lifting jack 2 is installed as shown in Figure 1b.
a to 2d [illustrated 2a, 2c] are tires 5A to 5
D [5A, 5C shown] is suspended to support the entire weight.

By the way, when the work vehicle is stopped on a level ground, if the lifting jacks 2a to 2d are equally extended to support the vehicle body, the on-board work equipment such as the gondola and crane can be operated within the specified range. can be done. However, when the work vehicle is stopped on a slope, the lifting jacks 2a to 2
If d were extended to the same extent, the vehicle body would also be in a tilted state, and the distance between the front and rear or left and right horizontal support by the outriggers would be shortened. As a result, the range in which the overturning moment of the vehicle body exerted by the work equipment and the suspended object can be maintained becomes narrower than in the case on a level ground, and the operating range of the work equipment is restricted. Therefore, if you want to set the car body horizontally, it is necessary to extend and retract each outrigger independently, and you have to do it gradually while taking care not to make the car body support three points during the setting process. There are problems that require time and skill.

[Problem to be solved by the invention]

By the way, for example, the Japanese Patent Publication No. 40-14486 is a device that can keep the vehicle body horizontal even on slopes by varying the amount of extension and contraction of the outriggers.
There is an automatic control device described in the publication. This system is equipped with a posture switch that detects the tilt of the vehicle body in the front, rear, left, and right directions, while also providing a communication pipe for each of the four hydraulic jacks that move each outrigger up and down, separate from the original pressure oil supply and drainage route. An electromagnetic on-off valve is installed to communicate or shut off the upper and lower chambers of the hydraulic jack. When using such a device to level the car body, first raise the car body by maximizing the stroke of all hydraulic jacks. When the above-mentioned attitude switch is operated at that point, an electromagnetic on-off valve attached to a hydraulic jack for the outrigger located at a high position is opened. Therefore, the hydraulic jack that communicates the upper chamber with the lower chamber is reduced by the weight of the vehicle body, and the pressure oil in the upper chamber moves to the lower chamber, shortening the leg length of the outrigger. When the vehicle body becomes horizontal, the electromagnetic on-off valve is closed by the return of the attitude switch, communication between the upper chamber and the lower chamber is cut off, and the contraction operation of the outriggers is stopped.

Through this automatic control operation, even if the work vehicle is stopped on a slope, the vehicle body remains level, ensuring a wide range of stable work. However, since the high-pressure oil in the upper chamber is allowed to enter the lower chamber without draining, a new communication line must be installed in the hydraulic jack, and the electromagnetic on-off valve operated by the attitude switch must be installed in the hydraulic jack. Since it must be installed separately from the hydraulic switching valve required to supply and discharge pressure oil to the jack, the number of parts for the automatic control device increases, making the system complicated and increasing costs. There is.

In addition, in the structure of the above-described device, even if the vehicle body cannot be set horizontally even though the piston has made a full stroke, the automatic control operation is still maintained in the ON state. Therefore, the operator cannot immediately grasp whether the leveling operation has been completed or whether the leveling operation has stopped due to the inability to level the object, which is disadvantageous and inconvenient in that the operator feels confused about the leveling operation. In addition, if the outriggers contract too much while the pressure oil is being moved to level the vehicle and the vehicle is still tilting even when the tires are in contact with the ground, the automatic control operation will be maintained and the outriggers will The intended purpose of leveling the vehicle body using a chisel cannot be achieved.

On the other hand, an example was published in Japanese Patent Application Laid-Open No. 1983-1983 in which an alarm was issued when the vehicle body could no longer be set horizontally.
It is described in Publication No. 13244. In such devices, a pressure sensitive switch is connected to each of the pilot lines leading to the high pressure chamber of the jet cylinder, and when high positive pressure is applied to the pilot line, the contacts close, and high positive pressure is applied. It is designed to be open when not in use. All of these pressure sensitive switches are connected in series, and when any one of the pressure sensitive switches opens and the jack cylinder reaches the end of its stroke, a buzzer sounds. In addition, when entering the horizontal setting operation, all the jack cylinders are gradually extended, and if the vehicle body is level during that time, high positive pressure is applied to all pressure sensitive switches, their contacts close, and all the jack cylinders are extended. Pressure oil is supplied to the cylinders through their respective on-off valves, and the extending operation of the cylinder is maintained until the cylinder reaches its stroke end. On the other hand, if the car body is tilted, the pressure acting on one of the pressure sensitive switches will not be high positive pressure, and the contact will open and pressure oil will not be supplied to the corresponding high position jack cylinder. blocked. The above buzzer is
While the vehicle is being leveled, the low-positioned jack cylinder reaches the end of its stroke, but when the level is still not leveled, it makes a noise.

This control operation is not based on a method in which the jack cylinder is set at its maximum stroke and then the corresponding jack cylinder is gradually reduced.
This is an operation that gradually extends the jack cylinder from the beginning. Therefore, when the car body is tilted and the jack cylinders in the lower positions have extended to a certain extent, the jack cylinders in the higher positions do not extend, and the car body is tilted while the tires in the higher positions are still in contact with the ground. It may become horizontal. Even if you can set it horizontally, the vehicle body will still be supported by the tires and outriggers.
There is a problem that four-point support by outriggers cannot be achieved.

The present invention was made in order to solve the above-mentioned problem, and its purpose is to set all the outriggers to the maximum stroke in advance when supporting the vehicle body even on a slope, and then move one of the outrigger lifting jacks to the maximum stroke. By reducing the size of the vehicle, the vehicle body can be quickly set horizontally, and the possible displacement range of the work equipment mounted on the work vehicle can be made the same as that on horizontal ground, and if horizontal setting is not possible, it is possible to It is possible to automatically notify the worker to alert them, and the leveling must be achieved with all outriggers supporting the vehicle body, and the vehicle should be lifted so that it is not even partially supported by the tires. It is possible to automatically control operation within the range of the effective stroke limit at the time when the jacking is reduced and the outriggers supporting the car body are transferred to support by the tires, ensuring safe support and stability of the car body, and horizontal setting. To simplify the equipment without complicating the hydraulic control valve and pressure oil piping by making the switching valve required for the outrigger common with the original supply/discharge valve that supplies pressure oil for the expansion and contraction of the outrigger. It is an object of the present invention to provide a vehicle body leveling device for a work vehicle having an outrigger that realizes the following.

[Means to solve the problem]

The present invention enables a work vehicle equipped with outriggers on the front, rear, left, and right sides to be stopped on a slope to perform various types of work.
The present invention is applied to a vehicle body leveling device in which all outriggers are extended to their maximum strokes in advance and the outrigger lifting jacks located at a high position are reduced in order to level the vehicle body.

Its features are as follows with reference to FIGS. 1a, b and 2: lifting jacks 2a to 2d
The vehicle is equipped with electromagnetic switching valves 18a to 18d that can be switched independently to supply and discharge pressure oil for each vehicle, and is provided with inclination detection means 10 for detecting the presence or absence of inclination of the vehicle body in the longitudinal and lateral directions. And each outrigger 2A~
Effective stroke detection means 13a to 13a to detect that the 2D lifting jacks 2a to 2d have shrunk and reached the effective stroke limit from the time when the outriggers supporting the vehicle body are transferred to support by tires.
13d, and maximum stroke detection means 14a-14d for detecting when each lifting jack 2a-2d has reached its maximum extension state.

On the other hand, maximum stroke detection means 14a to 14d
After detecting the maximum extension state, the inclination detection means 10
When a tilt in the front and back direction is detected, the two lifting jacks on the front or rear are reduced, and when a tilt in the left/right direction is detected, the two lifting jacks on the left or right are reduced. The electromagnetic switching valves 18a to 18d interposed in the hydraulic drive circuit of the lifting jack are switched to issue a command to drain the pressure oil in the lifting jack, and when the effective stroke detection means 13a to 13d detect the effective stroke limit, the vehicle body Control means 17 for issuing an alarm command indicating that horizontal setting is impossible
and an alarm means 19 which issues an alarm in response to a command from the control means 17.

〔Effect of the invention〕

According to the present invention, the maximum stroke detection means detects that the lifting jack is in the maximum extension state, and in that state, based on the signal from the inclination detection means, the lifting jack is reduced in pairs front and rear or left and right. As a result, a work vehicle stopped on a slope can be automatically and quickly leveled. At this time, automatic control is performed within the range where the tires do not touch the ground, ensuring safe leveling operation. Further, if the setting is impossible, a warning is issued, so the operator can know that the horizontal setting is impossible. If the vehicle body is set horizontally, even when the work vehicle is stopped on a slope, the mounted operating equipment can be operated within a desired range, just as when the work vehicle is stopped on a level ground. In addition, there is no need to install new hydraulic equipment such as a hydraulic control valve or piping for this automatic leveling control, which simplifies and lowers the cost of the device itself and reduces the failure rate. Can be done.

〔Example〕

Hereinafter, the present invention will be explained in detail based on examples thereof.

FIG. 2 is a structural block diagram of a vehicle body leveling device for a working vehicle having outriggers according to the present invention. In the figure, reference numeral 10 denotes an inclination detection means for detecting the presence or absence of inclination of the vehicle body in the longitudinal and lateral directions, and includes a longitudinal inclination detection sensor 10a and a lateral inclination detection sensor 10b. These tilt detection sensors 10a, 10b
For example, as shown in FIG. 3, the contacts 12F and 12B are
As shown in Figure 1a, these switches are installed toward the front, rear, left and right sides of the center of the vehicle, respectively. Note that the front-rear tilt detection sensor 10a and the left-right tilt detection sensor 10b may be integrated so that when mercury moves in an arbitrary direction, a contact at that position can be energized.

13 and 14 are sensors for detecting the effective stroke limit and maximum stroke of the vehicle body lifting jacks 2a to 2d of each of the outriggers 2A to 2D, and constitute stroke detection means. These are limit switches that are attached to each jack arm 15 having built-in lifting jacks 2a to 2d, as shown in FIG. 4, and are operated by the movement of a jack inner arm 15b that moves up and down below the jack outer arm 15a. . The effective stroke limit is the stroke at which the lifting jacks extend and the tires that support the car body begin to separate from the ground.If applied to this example, the lifting jacks shrink and the tires supporting the car body begin to move away from the ground. This is the stroke at the point where the outrigger moves from being supported by the tires. The maximum stroke is the stroke when the lifting jack is extended to its maximum extent.

Reference numeral 17 denotes a control means for reducing the two front and rear lifting jacks shown in FIG. 6 when a longitudinal inclination is detected by the inclination detecting means 10, and when a horizontal inclination is detected. In order to reduce the two lifting jacks on the left or right side, the solenoids 18n that switch the electromagnetic switching valves 18a to 18d interposed in the hydraulic drive circuits of the lifting jacks 2a to 2d are energized, and the effective stroke detection means 13 is activated. When the stroke limit is detected, a warning command is issued to the effect that the vehicle body cannot be set horizontally. In addition, solenoid switching valve 1
8 is not newly provided to horizontally set the vehicle body, but originally corresponds to each lifting jack 2a to 2d in order to supply and discharge pressure oil to the lifting jacks 2a to 2d for grounding or retracting the outriggers. It is set up as follows. These electromagnetic switching valves 18 are
It also functions to drain the pressurized oil in the lifting jack directly into the tank even when it is reduced for horizontal setting.

19 (see FIG. 2) is a warning means such as a buzzer that receives a signal from the control means 17 and issues a warning to the operator. It goes without saying that other types of equipment may be used as long as this alarm can be recognized by the five senses. 20 converts the signal from the control means 17 and connects the electromagnetic switching valve 18
This is an interface for outputting to the alarm means 19 and alarm means 19. 21 is an operation command switch, and a power supply 22
It supplies electric power to the control means 17 and also issues operation commands to the automatic control system. This switch 2
1 is provided separately from the one for the manual operation system of the outrigger, and when this is connected, the automatic control system according to the present invention is activated, and when it is not connected and another switch is connected, the lifting jacks 2a to 2d are Each of these can be expanded and contracted independently by manual operation.

23 is a tilt angle detection means for detecting the tilt angle of the vehicle body in the longitudinal and lateral directions, and includes a longitudinal tilt angle detection sensor 23a and a left and right tilt angle detection sensor 23b. Depending on the angle of inclination of the ground on which the vehicle is stopped, lifting jacks 2a to 2 may be
No matter how much d is reduced, it may not be possible to horizontally set the vehicle body, so this is used to detect whether or not horizontal setting is possible and determine whether or not the automatic control system needs to operate.

According to the embodiment with the above-described configuration, the vehicle body can be set horizontally by the outriggers in the following manner. In addition, to make it easier to understand the operation,
This will be explained with reference to the flowchart shown in FIG.

First, after stopping the vehicle body, an operator connects the switch 21 to operate the automatic control system (step 1 of the flowchart, hereinafter referred to as S1). Upon receiving this signal, the control means 17 moves the respective electromagnetic switching valves 18a to 18d from the neutral state via the interface 20 in order to extend the overhanging jacks and lifting jacks 2a to 2d (not shown) of all the outriggers 2A to 2D. Leave it open. Regarding the lifting jacks 2a to 2d, all the electromagnetic switching valves 18a to 1 shown in FIG.
By energizing each solenoid 18m of 8d, the extension side port 18p opens, and the hydraulic oil from the hydraulic pump 24 is supplied to the lifting jacks 2a to 2d shown in FIG. 6, causing them to extend (S2).

When the maximum stroke detection sensors 14a to 14d detect the maximum extension state of all lifting jacks 2a to 2d (S3), all of the solenoids 18m mentioned above are demagnetized and the extension of lifting jacks 2a to 2d is stopped, and at that point the vehicle body is parallel to the sloping ground. At this time, the longitudinal inclination angle sensor 23a
detects the inclination angle of the vehicle body, and detects whether the inclination angle is such that it can be set horizontally in the longitudinal direction by reducing any of the lifting jacks 2a to 2d, for example, within 7 degrees.

If the inclination angle in the longitudinal direction is within 7 degrees (S4),
Due to the inclination of the vehicle body, the mercury 11 shown in FIG. 3 has already flowed to the contact point 12F or 12B.
Since F is in the connected state, the signal is input to the control means 17. In order to reduce the two rear lifting jacks 2c and 2d through the interface 20, the electromagnetic switching valves 18c and 18d are
The solenoid 18n is energized and the reduction side port 1
8q opens, and lifting jacks 2c and 2d begin to reduce (S5).

Unless the effective stroke detection sensors 13c, 13d detect the effective stroke limit of both lifting jacks 2c, 2d (S6), both lifting jacks 2c, 2
d is reduced. When the vehicle body becomes horizontal in the longitudinal direction (S7), the mercury 11 of the longitudinal inclination detection sensor 10a is at the intermediate position, so the contact 12F is disconnected and the solenoid 18n is demagnetized. As a result, the electromagnetic switching valves 18c, 18d become neutral, and the reduction of the lifting jacks 2c, 2d is stopped.

On the other hand, the left and right tilt angle sensor 23b detects the tilt angle of the vehicle body, and it is determined that the tilt angle of the vehicle body is
By reducing a to 2d, it is detected whether the inclination angle is such that horizontal setting is possible in the left-right direction, for example, within 5 degrees. If the inclination angle in the left-right direction is within 5 degrees (S4), the contact 12L is in a connected state, for example, due to the mercury 11 being biased due to the inclination of the vehicle body. The signal is input to the control means 17,
In order to reduce the two right lifting jacks 2b, 2d, the solenoids 18n of the electromagnetic switching valves 18b, 18d are energized. Reduction side port 1
8q opens, and lifting jacks 2b and 2d begin to reduce (S8). Effective stroke detection sensors 13b and 13d are connected to both lifting jacks 2b and 2d.
Unless the effective stroke limit of (S9) is detected,
Both lifting jacks 2b and 2d are reduced in size.

If the car body becomes horizontal in the left and right direction (S10),
The mercury 11 of the left/right tilt detection sensor 10b is at the intermediate position, the contact 12L is disconnected, and the solenoid 18n is demagnetized. Solenoid switching valve 18b, 18
d is in a neutral state, and the lifting jack 2b,
The reduction of 2d is stopped. Note that when the front and rear directions become non-horizontal due to the horizontal setting in the horizontal direction (S11), the mercury 11 of the front and rear inclination detection sensor 10a connects, for example, the contact 12B, and the previous lifting jacks 2a and 2b are reduced (S5). ).

If the vehicle body becomes horizontal in both the front, rear, right and left directions, the alarm means 19 will not issue an alarm, so when the operator instructs the boom 3 (see Figure 1b) to extend/contract, undulate, turn, etc. The gondola 4 can be displaced within a desired wide range of support in the same way as when it is horizontal. Therefore, there is no need to consider limiting the displacement range of the gondola 4 in consideration of rollover of the vehicle body when the vehicle body is not set horizontally.

Note that if it is detected in step 4 that the vehicle body is tilted by 7 degrees or more in the front-rear direction and 5 degrees or more in the left-right direction, the vehicle body cannot be leveled even if the predetermined lifting jack is reduced. In that case, the buzzer which is the alarm means 19 sounds (S12). In this case, the operator may use a separate manual operation system to extend and retract the lifting jacks individually to determine whether to level the vehicle body or allow a certain degree of inclination. Additionally, when the effective stroke limit of the lifting jack is detected in steps 6 and 9, the tire at the position corresponding to the reduced lifting jack will touch the ground and can no longer be supported by the outrigger, so the buzzer will sound. Pronounce (S12). In this case as well, the vehicle body may be leveled using a separate manual operation system as described above. In addition, in the above-mentioned operation, the horizontal direction is taken before the horizontal direction, but conversely, the horizontal direction can be taken before the horizontal direction, or it can be taken at the same time. You may also do so.

By the way, in the above embodiment, the inclination angle detection means 2
3, the angle of inclination of the vehicle body is also detected, and a warning is issued if the vehicle body cannot be set horizontally, but if this is not necessary, the inclination detection means 10 detects whether or not the vehicle body is tilted. The control means 17 may be activated only upon detection of .

As explained in detail above, after the maximum stroke detection means detects that the lifting jack is in the maximum extension state, the lifting jack is reduced in front and rear pairs or in left and right pairs using a signal from the inclination detection means. A vehicle stopped on a slope can be automatically leveled using all outriggers. Also. If this setting is not possible, a warning will be issued and the operator will immediately know that automatic leveling is not possible. When the vehicle body is set horizontally, even when the work vehicle is stopped on a slope, the mounted operating equipment can be operated within a desired range, just as when the work vehicle is stopped on a level ground. This device is equipped with various detection sensors,
There is no need to add a hydraulic control valve or the like as a hydraulic device, and the problem can be dealt with by issuing a command to a conventional electromagnetic switching valve for a lifting jack. Furthermore, the pressure oil in the lifting jack for horizontal setting is discharged by draining it into a tank with low pressure, and the horizontal setting operation by the outriggers can be performed easily and quickly.

[Brief explanation of drawings]

Fig. 1a is a plan view of an example of a working vehicle having a gondola at the tip of the boom, Fig. 1b is a view taken along the - line in Fig. Fig. 3 is a sectional view showing an example of a tilt detection sensor, Fig. 4 is a sectional view of a jack arm of one outrigger with a built-in lifting jack, Fig. 5 is a solenoid energization circuit diagram of an electromagnetic switching valve, and Fig. 6 is the hydraulic circuit diagram of the lifting jack,
FIG. 7 is a flowchart showing the operating procedure. 2A to 2D... Outrigger, 2a to 2d... Lifting jack, 10... Incline detection means, 13...
...Effective stroke detection means (sensor), 14...
Maximum stroke detection means (sensor), 17... control means, 18, 18a to 18d... electromagnetic switching valve,
19...Warning means.

Claims (1)

[Claims] 1. When a work vehicle equipped with outriggers on the front, rear, left, and right sides is stopped on a slope to perform various operations, all the outriggers are extended to their maximum stroke in advance, and the vehicle is placed at a high height in order to level the vehicle body. The vehicle body leveling device is designed to reduce the lifting jack of the outrigger in the position. an inclination detection means for detecting the presence or absence of the vehicle; and an effective stroke detection means for detecting that the lifting jerk of each of the outriggers is reduced and an effective stroke limit is reached from the time when the outriggers supporting the vehicle body are shifted to support by the tires. and maximum stroke detection means for detecting that each lifting jack has reached its maximum extension state; and after the maximum stroke detection means detects the maximum extension state, when the inclination detection means detects a longitudinal inclination; In order to reduce the front or rear two lifting jacks, and also to reduce the left or right two lifting jacks when a horizontal tilt is detected, a hydraulic drive circuit of the lifting jack is inserted. Control means that switches the electromagnetic switching valve to issue a command to drain the pressure oil in the lifting jack, and when the effective stroke detection means detects an effective stroke limit, issues an alarm to the effect that horizontal setting of the vehicle body is impossible. 1. A vehicle body leveling device for a work vehicle having an outrigger, comprising: and an alarm means for issuing an alarm in response to a command from the control means.