JPH031448B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention enables excavation of roads, etc., and narrows the turning range during the work to prevent other work from being done or the progress of vehicles by occupying the road. The present invention relates to an excavator that can be used as an excavator, and more particularly to a control mechanism for an excavator that can expand the working range by freely stopping the swivel base at a predetermined angular position.

In conventional excavators, the arm protrudes from the vehicle body,
A bucket was attached to the tip of this arm to dig up the dirt, but with this configuration, when transferring the excavated dirt to the rear of the vehicle, the arm and bucket protrude far beyond the side of the vehicle and come into contact with people standing nearby. In addition to being dangerous, it also had the disadvantage of widening the work area. For this purpose, a swivel platform and a workbench are installed on the vehicle body with their rotational axes eccentric, and the bucket is passed above the vehicle body, and the excavation is configured so that the arm and bucket do not protrude far beyond the side of the vehicle. machine is proposed. However, with this new excavator, both the swivel platform and the work platform must be rotated in a predetermined direction, and if these rotations are not synchronized, the bucket will not reliably pass over the vehicle body, and the swivel mechanism is complicated. It had no choice but to become. For this reason, in the past, the swivel platform and the work platform were linked and synchronized by a mechanical drive mechanism using gears, etc., but the stress was concentrated at one point, which could easily cause a failure. The power loss due to friction etc. was large and the efficiency was poor. For this reason, a configuration has been proposed in which the above-mentioned problem is solved by rotating the swivel platform and the work platform using hydraulic motors and synchronizing the rotations of both hydraulic motors. are always linked and synchronized, so even if the swivel table is turned in the required direction, the work table will not necessarily be turned in the required direction, and excavation work can only be performed in a limited area in front or behind the vehicle body. The degree of freedom was limited.

In view of the above-mentioned drawbacks, the present invention rotates the swivel platform and the work platform using separate motive power, detects the rotational angular position of the swivel platform and the work platform, and compares the rotational angular position with a preset angular position. This allows the swivel base to stop at a freely set rotation angle position, and also allows the work platform to be stopped at a predetermined position relative to the swivel base. This invention provides a control mechanism for an excavator that can be expanded to expand the range of excavation work.

An embodiment of the present invention will be described below.

Figure 1 is a perspective view of this embodiment, Figure 2 is a side view,
FIG. 3 is a front view, and FIG. 4 is a plan view. This excavator is self-propelled, and has wheels 11 pivoted at its four corners on the lower surface of a flat vehicle body 10.
A caterpillar (endless track) 12 is wound between each pair of wheels 11 on both sides of the vehicle body 10.
An annular support plate 13 is fixed to the center of the upper surface of the vehicle body 10, and a deformed octagonal swivel table 14 is pivotably supported on the support plate 13 so as to be horizontally rotatable. The swivel base 14 has a planar shape with each vertex of an equilateral triangle cut out, and an engine 15 and a fuel tank are installed along the periphery of the swivel base 14 at the upper rear of the swivel base 14 (on the left side of FIGS. 2 and 4). 16, the hydraulic oil tank 17 is mounted and fixed, and the swivel base 14
A hydraulic motor 18 is fixed at a position slightly closer to the fuel tank 16 than the center of the upper surface with its drive shaft directed downward. In front of this swivel table 14 (second
A ring-shaped holding plate 19 is mounted and fixed on the upper part of the support plate 19 (right side in Fig. 4), and the center axis of the above-mentioned support plate 13 and the center axis of this holding plate 19 are offset in the horizontal direction. and parallel to each other. On this holding plate 19 is a circular workbench 20.
is rotatably supported on the holding plate 19,
A support body 21 is fixed vertically on the workbench 20, and coupling tools 22 are fixed to the support body 21 at intervals above and below. A proximal end body 26 is connected between the connectors 22, and a dogleg-shaped boom 27 is swingably connected to the proximal end body 26. An arm 28 is swingably connected to the tip of the boom 27. The arms 28 are movably connected, and furthermore, a bucket 29 is swingably connected to the tip of the arm 28. Between the proximal body 26 and the center of the boom 27, between the center of the boom 27 and the end of the arm 28, and between the center of the boom 27 and the end of the arm 28,
A hydraulic cylinder 3 is connected between the
0, 31, and 32 are interposed. this boom 2
7. Excavation mechanism 48 with arm 28, bucket 29, etc.
is configured. Further, a passenger platform 23 made of a steel plate bent into an L shape is fixed to one side of the base body 26, and a seat 24 and a control box 2 are mounted on the passenger platform 23.
5 is fixed.

Next, FIG. 5 shows the turning mechanism in this embodiment in detail, and corresponds to the sectional view taken along the line A--A in FIG. 4. A circular driving gear 33 having approximately the same outer diameter as the supporting plate 13 and having a tooth profile cut on its inner periphery is fixed on the support plate 13 described above, and a bearing 34 is mounted on the outer periphery of this driving gear 33. A ring-shaped slider 35 is rotatably fitted therebetween, and the swivel base 1 is mounted on the upper surface of this slider 35.
4 is fixed, and the swivel base 14 is attached to this driving gear 3.
It can be rotated around 3. A pinion 37 is rotatably attached to the output shaft 36 of the hydraulic motor 18, and the pinion 37 is meshed with an internal tooth surface of the driving gear 33. Further, a ring-shaped shaft support 38 is fixed on the holding plate 19 and has an outer diameter that is approximately the same as that of the holding plate 19. A driven gear 39 that has approximately the inner diameter of the shaft support 38 and has a tooth profile cut on its inner periphery.
, and a pairing 40 is interposed between the shaft support 38 and the driven gear 39. The workbench 20 described above is mounted and fixed on the upper surface of the driven gear 39, and can rotate about the central axis of the shaft support 38 of the workbench 20. A holding plate 19 is mounted on the front upper surface of the swivel table 14.
A hydraulic motor 41 is fixedly located inside the hydraulic motor 41. A pinion 43 is rotatably attached to an output shaft 42 of the hydraulic motor 41, and the pinion 43 is meshed with an internal tooth surface of the driven gear 39. And support plate 1
A support post 44 is fixed vertically at the axis of the drive gear 33 on the top of the drive gear 33, and an angle detector 45 is fixed to the lower surface of the swivel base 14 that corresponds perpendicularly to the support post 44. It is placed close to the angle detector 45. A support 46 is also vertically fixed to the axis of the driven gear 39 on the swivel base 14.
An angle detector 47 is also fixed to the lower surface of the corresponding workbench 20, and the support column 46 and the angle detector 47 are placed close to each other. In addition, FIG. 6 is an exploded perspective view of the rotating member of this turning mechanism, and FIG. 7 is a plan view showing the positional relationship of the rotating member same as above.

FIG. 8 is a block diagram of an electric circuit showing a rotation angle detection and control system in this embodiment. Inside the angle detectors 45 and 47, there are disk-shaped magnetic disks 51 and 5, each having magnetic poles arranged at equal intervals on the outer periphery.
2 and magnetic pick-ups 54 and 55 are housed therein, the magnetic disk 51 is fixed to the top of the column 44, and the magnetic disk 52 is fixed to the top of the column 46, so that the magnetic disks 51, 52
The rotation table 14 and the work table 20 rotate relative to each other. magnetic pick up 53
The output of the magnetic pickup 54 is inputted to a gate circuit 58 via a pulse generation circuit 55 that generates a number of pulses according to the input signal, a buffer circuit 56, and a frequency Frequency divider circuit 5 that reduces the frequency by half
7 and is input to the gate circuit 61. next,
Reference numerals 62 and 63 designate swing switches provided near the control box 25 to operate the hydraulic motors 18 and 41, both of which operate simultaneously. A chattering prevention circuit 64 is connected to this swing switch 62, and the chattering prevention circuit 64 is connected to a gate circuit 61 and a one-shot multi-circuit 66 via a buffer circuit 65. is connected to the S terminal of the RS flip-flop 67, and a relay 69 is connected to the Q terminal of the RS flip-flop 67 via a drive circuit 68. A power source is connected to one end of this relay 69, and a solenoid 70 is connected to the other end. The swing switch 63 is also connected to a gate circuit 58 and a one-shot multi-circuit 72 via a chattering prevention circuit 71 and a buffer circuit 72.
is connected. The output of the gate circuit 61 is input to the count input T of the counter 74, the output of the gate circuit 58 is input to the count input T of the counter 75, and the outputs of both counters 74 and 75 are input to the comparison and coincidence circuit 76. While typing,
The output of the counter 74 is input to a coincidence circuit 77, and the output of the counter 75 is input to a coincidence circuit 78. A signal from a count storage circuit 79 is also input to this coincidence circuit 77, and this count storage circuit 79 always outputs a signal corresponding to the number of counts when the workbench 20 rotates 360 degrees. , this memory count number is fixed. The judgment output of the coincidence circuit 77 is input to the R terminal of the RS flip-flop 67 and also to the one shot multi circuit 80, and the output of the one shot multi circuit 80 is input to the clear terminal of the counter 74. . The coincidence circuit 78 includes a count setting circuit 81 that outputs a set count number.
The output of this count setting circuit 8 is input.
A setting device 82 is connected to 1, and the setting device 82 changes the stopping position of the swivel base 14 with a dial.
It can be set by dividing 360 degrees into two parts and specifying different counts each time. The judgment output of the matching circuit 78 is output to the one shot multi circuit 83. Also,
The comparison and coincidence circuit 76 discriminates the count outputs of the counters 74 and 75, and has a comparison output K that is output when both outputs do not match, and a coincidence output J that is output when both outputs match. is RS
The matching output J is input to the S terminal of the flip-flop 84, the Q output of the RS flip-flop 84 is input to the S terminal of the RS flip-flop 86, and the output of the OR gate 85 is input to the R terminal of the RS flip-flop 86. It is entered at the end. The output of the one-shot multi-circuit 83 is input to the setter 82, the R terminal of the RS flip-flop 84, the OR gate 85, and the clear terminal of the counter 75, and the output of the one-shot multi-circuit 73 is input to the S terminal of the RS flip-flop 86. is being input. And the Q of RS flip-flop 86
The output is connected to a drive circuit 87, a relay 88 is connected to the drive circuit 87, and a relay 88 is connected to the drive circuit 87.
A power source is connected to one end, and a solenoid 77 is connected to the other end.

Next, FIG. 9 is a system diagram showing the hydraulic system of this embodiment, in which the discharge passage 92 of the hydraulic pump 91 is branched into two, and each of the branched discharge passages 92 has a throttle valve 93, Solenoid valves 95, 96 via 94
The flow rate of the throttle valve 94 is controlled by the throttle valve 93.
It is set to twice that of . The solenoid valve 95 is operated by the solenoid 89, and the solenoid valve 96 is operated by the solenoid 70. A hydraulic motor 18 is connected to the solenoid valve 95, a hydraulic motor 41 is connected to the solenoid valve 96, and a recovery path 97 is connected to the output ends of both hydraulic motors 18, 41. The terminal end of 97 is connected to a pressure oil tank 98. This pressure oil tank 9
8 is filled with pressure oil, and the hydraulic pump 9
The first suction passage 99 is introduced into the pressure oil tank 98.

Next, the operation of this embodiment will be explained.

First, a case will be described in which the swivel base 14 is rotated 180 degrees at a time and then stopped. In this case, the setting device 82 is set to the "0" position. When this setter 82 is set to "0", the count setting circuit 81
outputs a signal indicating the number of counts for a rotation of 180 degrees, and a signal for 180 degrees can be set for each signal from the one-shot multi-circuit 83.

The operation of moving the bucket 29 up and down to excavate roads and the ground has traditionally been a public movement operation, and the seat 2
By operating the control box 25 by an operator aboard the vehicle 4, the hydraulic cylinders 30, 31, and 32 are made to work together in an interlocking manner. The excavated soil is removed by lifting the bucket 29 horizontally as shown in FIG. This allows it to be transferred to a truck, etc.

To rotate the swivel table 14 and the workbench 20, the swivel switches 62 and 63 are closed to instruct the swivel to rotate, and the one-shot multi-circuits 66 and 73 are routed through the chattering prevention circuits 64 and 69 and the buffer circuits 65 and 70. Pulses Pc and Pd, which are generated only while the swing switches 62 and 63 are closed, are transmitted to the gate circuits 58 and 61. The one-shot multi-circuits 66 and 73 generate pulses with a predetermined pulse width, respectively, and send the pulses to the RS flip-flops 67 and 86.
, each RS flip-flop 67,8
6, the output at the Q end rises. Therefore, the drive circuits 68 and 87 close the relays 69 and 88 to supply current to the solenoids 70 and 89, and operate the solenoid valves 95 and 96 to direct the hydraulic pressure from the hydraulic pump 91 to the hydraulic motor through the throttle valves 93 and 94. 1
8,41 to be supplied. For this reason, the hydraulic motor 1
8 operates, and when this hydraulic motor 18 operates, the output shaft 36 and pinion 37 rotate, rotating the gears of the driving gear 33 that are meshed with each other, so that the slider 35
will rotate along the drive gear 33, and the swivel base 14 will rotate relative to the vehicle body 10. Furthermore, when the hydraulic motor 18 operates, the output shaft 42 and pinion 43 of the hydraulic motor 41 rotate, causing the engaged driven gear 39 to rotate along the shaft support 38 . For this purpose, the workbench 20, support body 21, and excavation mechanism 48 placed on the driven gear 39 are rotated with respect to the swivel base 14. Here, by setting the respective rotational directions of the hydraulic motors 18 and 41 in opposite directions, the rotational directions of the swivel table 14 and the workbench 20 are respectively reversed, and the excavation mechanism 48 fixed on the workbench 20 is It will pass above the turning table 14. Further, the flow rates of the throttle valves 93 and 94 are set so that the flow rate of the throttle valve 93 is "1" and the flow rate of the throttle valve 94 is "2". 2 of rotation speed
It will rotate twice.

When the above-mentioned turning table 14 and workbench 20 rotate, the angle detectors 45 and 47 change their angular positions relative to the supports 44 and 46, and the angle detector 4
Since the magnetic disks 51 and 52 in the magnetic disks 5 and 47 are fixed to the pillars 44 and 46, the angle detector 4
5,47, magnetic pick-up 53,5
4 detects fluctuations in magnetic poles set on the outer peripheries of magnetic disks 51 and 52, converts them into electrical signals, and transmits them to pulse generation circuits 55 and 59. In the pulse generation circuits 55 and 59, the magnetic pickups 53 and 54
A pulse wave whose waveform is shaped with a predetermined pulse width by the detection signal from the magnetic disks 51 and 52 is generated every fixed rotation angle of the magnetic disks 51 and 52. The pulse waves from the pulse generation circuits 55 and 59 are passed through the buffer circuits 56 and 60 as angle signals Pa and Pb, and then the frequency divider circuit 57 to the gate circuit 61 and gate circuit 58.
is output to. The gate circuit 61 receives the turning signal Pc from the turning switch 62 and the reduced pulse wave.
Pulse wave while Pb/2 is input
Outputs the same pulse wave Pe as Pb/2, and
Pe is input to the count input T of the counter 74, and the counter 74 counts the number of pulses. The count output of the counter 74 is transmitted to a comparison match circuit 76 and a match circuit 77. Next, the angle signal Pa input to the frequency dividing circuit 57 is transmitted as is to the gate circuit 58, and this gate circuit 58 outputs a pulse wave Pf with the same number of pulses as Pa while the turning signal Pd is input. Pulse wave Pf
is input to the count input T of the counter 75, and the counter 75 counts the number of pulses. The count output of the counter 75 is transmitted to a comparison and coincidence circuit 76 and a coincidence circuit 78, and the comparison and coincidence circuit 76 compares the count output from the counter 74 with this count output, and if the two outputs do not match, a signal is sent by the comparison output K. is output, and if the two match, a signal is output from the match output J. When the comparison output K of the comparison matching circuit 76 is "1", the Q terminal of the RS flip-flop 84 is "1".
The hydraulic motor 18 continues to operate with the output of . When the hydraulic motor 18 continues to operate and rotates the swivel base 14, and the rotation angle of the swivel base 14 becomes 2/1 of the rotation angle of the work platform 20, the count output values of the counters 74 and 75 match. , the comparison and coincidence circuit 76 outputs a coincidence output J of "1", reverses the RS flip-flop 86 through the OR gate 85, sets the Q terminal to "0", stops the drive circuit 87, opens the relay 88, and switches the hydraulic motor. 18 is temporarily suspended. As a result, the swivel base 14
The rotation of will stop temporarily. In this way, the counters 74 and 75 count the number of pulses of the pulse waves Pe and Pf, and the comparison and coincidence circuit 76 alternately outputs the comparison output K and the coincidence output J, and controls the solenoid 89 and hydraulic motor 18 in a stepwise manner. control hydraulic motor 1
A constant follow-up operation is always performed for the operation of step 4. Therefore, the magnetic disks 51, 52
will always rotate at a ratio of 1:2, and therefore the swivel base 14 and the workbench 20 will always rotate in a proportional relationship with a rotation angle of 1:2. Then, when the workbench 20 rotates more than the rotation angle of the swivel table 14, the comparison and coincidence circuit 76 transmits the comparison output K to the RS flip-flop 84, activates the drive circuit 87, relay 88, and solenoid 89 to cause the hydraulic motor 18 to follow. The error in the rotation angle is extremely small.

Next, since the count outputs of the counters 74 and 75 mentioned above are output to the matching circuits 77 and 78, respectively, the set counts from the count storage circuit 79 and the count setting circuit 81 input to each matching circuit 77 and 78 are After comparing the numbers, the matching circuit 77 outputs a judgment signal based on the count number of 360 degree rotations of the workbench 20 and inverts the RS flip-flop 67, thereby controlling the drive circuit 68, relay 69, and solenoid 7.
0, the operation of the hydraulic motor 41 is stopped via the solenoid valve 96, and at the same time, the counter 74 is cleared by the one-shot multi-circuit 80. Further, the coincidence circuit 78 compares the set count number from the count setting circuit 81 and transmits a judgment signal to the one shot multi circuit 83 based on the count number rotated 180 degrees from the counter 75.
outputs signals to the RS flip-flop 86 via the setter 82, RS flip-flop 84, counter 75, and OR gate 85, and the setter 8
2 sets the next count number, inverts the RS flip-flops 84 and 86, and sets the counter 75.
Clear. Since the RS flip-flop 86 is reversed, no signal is transmitted to the drive circuit 87 and the hydraulic motor 18 stops its operation. As a result, the swivel base 14 and the workbench 20 are accurately positioned at positions rotated by 180 degrees and rotated by 360 degrees, respectively.
The role of this setting device 82 will be explained with reference to FIG.
If the dial 100 of the setting device 82 is set to the deviation angle 0, the number of counts corresponding to the number of counts when the swivel base 14 rotates 180 degrees in response to one signal input from the one-shot multi-circuit 83 will be calculated. It is output from the count setting circuit 81. For this reason, the 10th
As shown on the right side of the figure, a count setting circuit 81 is provided while the swivel base 14 rotates from point a to point b behind the vehicle body 10.
outputs a set count, and at point b, the setter 82 is reset by a signal from the one shot multi circuit 83, and outputs a set count of 180 degrees from point b to point a. From this, the swivel base 14 is 180° when the deviation angle of the setter 82 is 0.
The swivel base 14 rotates and stops repeatedly, and the vehicle body 10
The vehicle will always stop in front and behind the vehicle.

The rotation of these two hydraulic motors 18 and 41 changes the relative relationship between the swivel table 14 and the work table 20.
To explain with the drawings, the workbench 20 starts to rotate in the X direction in the figure by the hydraulic motor 41, and the swivel table 14 starts to rotate in the Y direction in the figure by the hydraulic motor 18 (see illustration in FIG. 11). ). As mentioned above, the workbench 20
Since the rotation angles of the and swivel table 14 are controlled, their rotation speeds are regulated at a ratio of 2:1. Therefore, the workbench 20 rotates at twice the speed of the swivel table 14, and when the swivel table 14 rotates 90 degrees, the workbench 20 rotates 180 degrees, and since they are both rotating in the opposite direction, the workbench 20 rotates at the same speed as the swivel table 14. After being relatively rotated by 90 degrees, the excavating mechanism 48 is positioned perpendicular to the vehicle body 10, resulting in the state shown in FIG. 11B. Therefore, the workbench 20 is maximally deviated to one side of the vehicle body 10, and the excavation mechanism 48
is located above the turning base 14 and passes through without protruding from the other side of the vehicle body 10. moreover,
When the swivel table 14 rotates 90 degrees, the work table 20 rotates 180 degrees, the work table 20 moves to the right side of the car body 10, and the excavation mechanism 48 protrudes to the opposite side of the car body 10.
It moves to a position that is exactly reversed from the state shown in Figure 11A. In this state as shown in Fig. 11C, turn switch 6
2 and 63, the hydraulic motors 18 and 41 stop their operation, and the swivel table 14 and the work table 20 stop their rotation. In other words, the excavation mechanism 48 receives the rotation movement of the swivel table 14 on the vehicle body 10 and the rotation movement of the work table 20 on the swivel table 14 in the opposite direction, so that the excavation mechanism 48 rotates doubly. When rotating from the front to the rear of the vehicle body 10, the excavation mechanism 48 always passes above the swivel base 14 and rotates, and rotates within the maximum range so as not to protrude the excavation mechanism 48 to the side of the vehicle body 10. It turns out. Excavation mechanism 4
8 from the position C to the position A in Fig. 11, press the swivel switches 62 and 63 again and rotate the swivel 14 by 180 degrees. The table 20 is rotated at a constant ratio.

Next, a case in which the swivel base 14 is rotated toward the side surface of the vehicle body 10 will be described.

In this case, set the dial 100 of the setting device 82 to +90.
When the rotation is adjusted to the desired angle, the setter 82 alternately sends two types of signals to the count setting circuit 81 via the one-shot multi-circuit 83, setting the count number corresponding to a rotation of 90 degrees and setting the number corresponding to a rotation of 270 degrees. The count number is transmitted to the matching circuit 78. Therefore, as shown on the right side of FIG. 12, when the swivel base 14 rotates from point c to point d, the count number corresponding to the rotation of the swivel base 14 by +90 degrees or 270 degrees is transmitted to the matching circuit 78. It rotates 270 degrees and stops at point d. Next, when rotating from point d to point c, the setting device 82
The rotation of the swivel base 14 is 90 in the count setting circuit 81.
A count number corresponding to the degree is transmitted to the coincidence circuit 78, and the swivel table 14 stops at point c, which has rotated 90 degrees.

This rotational operation is performed by turning the swivel switch 6 in the same way as described above.
The pulse waves detected by the magnetic pickups 53 and 54 are counted by the counters 74 and 75 and transmitted to the matching circuits 77 and 78, respectively, and the matching circuit 77 stores the count memory circuit. Since the count number corresponding to the 360 degree rotation from 79 is output, the workbench 20
When the hydraulic motor 18 has rotated 360 degrees, a judgment signal is output to stop the rotation of the hydraulic motor 18. The coincidence circuit 78 outputs a judgment signal from the count setting circuit 81 when the swivel base 14 rotates 270 degrees to stop the rotation of the hydraulic motor 41 via the one shot multi circuit 83, and at the same time outputs a judgment signal to the setting device 82. convey the signal,
Instructing the next set count number, the count setting circuit 81 is set to a count number corresponding to a rotation of 90 degrees. Therefore, while the workbench 20 rotates 360 degrees, the swivel table 14 rotates 270 degrees and stops. When the swivel switches 62 and 63 are closed again, the workbench 2
0 rotates 360 degrees, whereas the swivel base 14 rotates 90 degrees, each stops, and returns to the initial position. From this, the rotation switch 6
When 2 and 63 are closed once, the swivel base 14 rotates 270 degrees, and when they are closed a second time, the swivel base 14 rotates once and stops.

The movement of the swivel table 14 and the workbench 20 will be explained with reference to FIG. 13.
When the swivel switches 62 and 63 are pressed in the state of A, the swivel base 14 rotates 90 degrees and stops, the work platform 20 rotates 360 degrees and stops, and the excavation mechanism 48 rotates the car body 10. The excavated earth and sand can be transferred to a truck or the like waiting behind the vehicle body 10. Then, when the swivel switches 62 and 63 are pressed again, the swivel base 14 rotates 270 degrees.
The workbench 20 is rotated 360 degrees to the state shown in FIG. 13A, and the excavation mechanism 48 can protrude to the side of the vehicle body 10 to excavate the side part. To change the stop position of this swivel base 14, use the dial 10 of the setting device 82.
By adjusting 0, you can freely set and change any angle.

Since the present invention is configured as described above, it is possible to make the bucket of the excavator as eccentric as possible and turn it from the front to the rear, and the bucket does not protrude from the side of the vehicle body, thereby interfering with the operation of other lanes. The road can be used efficiently without causing any problems or having the road occupied by excavation work. Since the rotational angle position and stop position of the swivel table can be freely changed and set, the scope of excavation work can be expanded by providing flexibility in the direction in which the excavation mechanism faces.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing one embodiment of the present invention;
The figure is a side view of the same as above, Figure 3 is a front view of the same as above, and Figure 4 is a front view of the same as above.
The figure is a plan view of the same as the above, Figure 5 is a sectional view taken along arrow A-A in Figure 4 showing the turning mechanism in detail, Figure 6 is an exploded perspective view showing the configuration of the turning mechanism of the above, and Figure 7 is the turning mechanism. An explanatory diagram showing the arrangement of the mechanism, Fig. 8 is a block diagram showing the electrical control system, Fig. 9 is a piping diagram showing the hydraulic system,
Fig. 10 is an explanatory diagram showing the relationship between the rotation angle of the setting device dial and the swivel table, Fig. 11 is an explanatory diagram showing the rotation order of the swivel table and the work table, and Fig. 12 is an explanatory diagram showing the rotation angle of the setting device dial and the swivel table. FIG. 13 is an explanatory diagram showing the relationship between the rotation angles of the rotating table and the working table. 10...Vehicle body, 14...Swivel table, 20...Work table, 18, 41...Hydraulic motor, 48...Drilling mechanism, 45, 47...Angle detector, 77, 78...
Matching circuit, 81... Count setting circuit, 82...
Setting device.

Claims (1)

[Claims] 1. A swivel table that can rotate horizontally is provided above the movable vehicle body, and a work table is provided on the top surface of the swivel table so that it can rotate freely, offset from the center of rotation of the swivel table.
In an excavator with the excavation mechanism fixed to the workbench,
A hydraulic motor for rotating the swivel table and a hydraulic motor for rotating the work table are provided separately, and a first rotation angle detection means detects the rotation angle of the swivel table, and a second rotation angle detecting means detects the rotation angle of the work table. and a signal processing means for inputting signals from the first and second rotation angle detection means, and a position setting means for setting the stop position of the rotating base is connected to the signal processing means. , an excavation characterized in that the operation of both hydraulic motors is controlled by the signal processing means, the swivel table is stopped at a set angular position, and the work table is always stopped at a constant position with respect to the swivel table. Machine control mechanism.