JPH031446B2 - - 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 prevented, and particularly relates to a control mechanism for an excavator that can smoothly operate the excavator.

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.

In view of the above-mentioned drawbacks, the present invention rotates the swivel table and the workbench using separate motive forces, detects the rotation angle of both with a detection device, and controls both motive forces by comparing and determining the detection results. death,
The present invention provides a control mechanism for an excavator that is capable of interlocking and synchronizing the rotations of a rotating platform and a work platform.

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 can be self-propelled, and a vehicle 11 is pivotally supported at the four corners of the lower surface of the flat body 10.
Caterpillars (infinite tracks) 12 are wound between a pair of wheels 11 on both sides of the vehicle body 10, respectively.
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 freely rotatable in the horizontal direction. 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 47 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.
A bearing 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 the workbench 20 can rotate about the central axis of the shaft support 38 as its rotation center. 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 5 is input to the 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 divider circuit 57 that reduces the frequency by half.
The output of 4 is the pulse generation circuit 59 and the buffer circuit 6.
It is input to the gate circuit 61 through 0. 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 move 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 drive circuit 66 via a buffer circuit 65. A relay 67 is connected to the drive circuit 66. It has been done. A power supply is connected to one end of this relay 67, and a solenoid 68 is connected to the other end. Further, a gate circuit 58 is connected to the swing switch 63 via a chattering prevention circuit 69 and a buffer circuit 70. The output of the gate circuit 61 is the count input T of the counter B71.
The output of the gate circuit 58 is input to the count input T of the counter A72, and the outputs of both counters A72 and B71 are input to the comparison and coincidence circuit 73.
is being input. The comparison matching circuit 73 is a counter A.
This is to determine the count output of 72 and B71.
There is a comparison output K that is output when both outputs do not match, and a match output J that is output when both outputs match.
The comparison output K is input to the S end of the RS flip-flop 74, and the coincidence output J is input to the RS flip-flop 74.
It is input to the R end of RS flipflop 7
The Q output of No. 4 is connected to a drive circuit 75, and a relay 76 is connected to the drive circuit 75. A power supply is connected to one end of the relay 76, and a solenoid 7 is connected to the other end of the relay 76.
7 is connected. Further, a one-shot multi-circuit 78 is connected to the output of the RS flip-flop 74, and the output of the one-shot multi-circuit 78 is input to the clear ends CL of the counters A72 and B71, respectively.

Next, FIG. 9 is a system diagram showing the hydraulic system of this embodiment, in which the discharge passage 82 of the hydraulic pump 81 is branched into two, and each of the branched discharge passages 82 has a throttle valve 83, Solenoid valves 85, 86 via 84
The flow rate of the throttle valve 84 is connected to the throttle valve 83.
It is set to twice that of . The solenoid valve 85 is operated by the solenoid 77, and the solenoid valve 86 is operated by the solenoid 68. A hydraulic motor 18 is connected to the solenoid valve 85, a hydraulic motor 41 is connected to the solenoid valve 86, and a recovery path 87 is connected to the output ends of both hydraulic motors 18, 41. The terminal end of 87 is connected to a pressure oil tank 88 . This pressure oil tank 8
8 is filled with pressure oil, and the hydraulic pump 8
The first suction passage 89 is introduced into the pressure oil tank 88.

Next, the operation of this embodiment will be explained.

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, an operator aboard the vehicle 4 causes the hydraulic cylinders 30, 31, and 32 to move in cooperation with each other. 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 rotation, and the drive circuit 66 and the gate circuit 58 are connected to each other via chattering prevention circuits 64 and 69 and buffer circuits 65 and 70. , 61 each have a turning switch 6.
Pulse that occurs only while closing 2,63
Pc and Pd are transmitted. Therefore, the drive circuit 66 closes the relay 67 to supply current to the solenoid 68, operates the solenoid valve 86, and operates the hydraulic pump 8.
1 to the hydraulic motor 4 through the throttle valve 84.
1. Therefore, the output shaft 42 and pinion 43 of the hydraulic motor 41 rotate to rotate the engaged driven gear 39 along the shaft support 38 . For this reason, the workbench 20 placed on the driven gear 39,
The support body 21 and the excavation mechanism 47 are rotated relative to the swivel table 14.

Next, since the comparison and coincidence circuit 73 outputs the comparison signal K (the condition is that the coincidence signal J is output before the swing switches 62 and 63 are pressed), the RS flip-flop 74 inverts and outputs the Q signal. The signal is transmitted to the drive circuit 75, and the drive circuit 75 closes the relay 76 to supply power to the solenoid 77. This solenoid 77 is activated, the solenoid valve 77 is turned on, and the hydraulic pressure from the hydraulic pump 81 is supplied to the hydraulic motor 18 via the throttle valve 83.
8 works. When this hydraulic motor 18 operates, the output shaft 36 and pinion 37 rotate and rotate the gears of the driving gear 33 that are meshed with each other, so that the slider 3
5 will rotate along the driving gear 33,
The swivel base 14 turns with respect to the vehicle body 10. Here, by setting the respective rotation directions of the hydraulic motors 18 and 41 in opposite directions, the rotation directions of the swivel table 14 and the work table 20 are respectively reversed, and the excavation mechanism 47 fixed on the work table 20 is rotated in opposite directions.
will pass above the turning table 14. Further, the flow rates of the throttle valves 83 and 84 are set so that the flow rate of the throttle valve 83 is "1" and the flow rate of the throttle valve 84 is "2". It will rotate at twice the rotation speed.

When the above-mentioned swivel table 14 and workbench 20 rotate, the angle detectors 45 and 47 change their angular positions relative to the supports 46 and 48, and the angle detector 4
Since the magnetic disks 51 and 52 in the magnetic disks 5 and 47 are fixed to the pillars 46 and 48, 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 outputted to the gate circuit 61 and the frequency dividing circuit 57 as angle signals Pa and Pb through the buffer circuits 56 and 60. The gate circuit 61 receives a turning signal from the turning switch 62.
While both Pc and pulse wave Pb' are being input, a pulse wave Pe that is the same as pulse wave Pb is output, and pulse wave Pe is input to counter input T of counter B71, and this counter B71 calculates the number of pulses. count. The count output of counter B71 is transmitted to comparison and coincidence circuit 73. Next, the angle signal Pa input to the frequency dividing circuit 57 has its frequency reduced to 1/2 and is transmitted as a pulse number of Pa/2 to the gate circuit 58. In this gate circuit 58, the rotation signal Pd is input. During this time, a pulse wave Pf with the same number of pulses as Pa/2 is output, and the pulse wave Pf is output by a counter.
The pulse number is inputted to the counter input T of A72, and the number of pulses is counted by the counter A72.
The count output of counter A72 is the comparison match circuit 7.
3, and in the comparison matching circuit 73, the counter B
The count output from 71 is compared with this count output, and if the two outputs do not match, a signal is output from the comparison output K, and when the two match, a signal is output from the match output J. This comparison matching circuit 73
When the comparison output K is "1", the RS flip-flop 74 continues to output "1" at the Q end and continues to operate the hydraulic motor 18. Hydraulic motor 18
continues to operate and rotates the swivel base 14, and when the rotation angle of the swivel base 14 becomes 1/2 the rotation angle of the work platform 20, the count output values of the counters A72 and B71 match, and the comparison matching circuit 73, the coincidence output J becomes "1", the RS flip-flop 74 is reversed and the end becomes "0", the drive circuit 75 is stopped, the relay 76 is opened, and the operation of the hydraulic motor 18 is temporarily stopped. As a result, the rotation of the swivel base 14 is temporarily stopped. At the same time, the Q terminal outputs "1", and the one shot multi circuit 7
8 generates one pulse wave with a predetermined pulse width, and this pulse wave of the one shot multi circuit 78 is transmitted to the clear end CL of each of the counters A72 and B71, and the count memories of both counters A72 and B71 are zeroed. to be reset. For this reason,
Counters A72 and B71 again generate pulse waves Pe and Pf.
The comparison matching circuit 73 starts counting the number of pulses.
outputs a comparison output K and a coincidence output J alternately, controls the solenoid 77 and the hydraulic motor 18 in a stepwise manner, reduces the cumulative error, and always performs a constant follow-up operation with respect to the operation of the hydraulic motor 14. It turns out. For this reason, the magnetic disk 51,
52 will always rotate by a 1:2 ratio, and therefore the swivel base 14 and the workbench 20 will always rotate in a proportional relationship with a 1:2 rotation angle. Then, when the workbench 20 rotates by a larger angle than the rotation angle of the swivel table 14, the comparison matching circuit 73 transmits the comparison output K to the RS flip-flop 74, actuating the drive circuit 75, relay 76, and solenoid 77 to follow the hydraulic motor 18. The error in the rotation angle is extremely small.

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. 10). As mentioned above, since the rotation angles of the workbench 20 and the swivel table 14 are controlled, their rotational speeds are regulated at a ratio of 2:1. When the swivel table 14 rotates 90 degrees, the work table 20 rotates 180 degrees, and since both are rotating in the opposite direction, the work table 20 rotates 90 degrees relative to the other, and the drilling mechanism rotates 90 degrees. 10th located at right angles to 10th
The situation will be as shown in Figure B. Therefore, the workbench 20 is maximally deviated to one side of the vehicle body 10, and the excavation mechanism 47 is located above the swivel base 14 and passes through the other side of the vehicle body 10 without protruding. Furthermore, when the swivel table 14 rotates 90 degrees, the work table 20 rotates 180 degrees, and the work table 20 moves to the right side of the vehicle body 10.
The excavation mechanism 47 protrudes to the opposite side of the vehicle body 10 and has a first
Move to a position that is exactly reversed from the state in Figure 0 A. In this state shown in FIG. 10C, the swing switch 62,
63, the hydraulic motors 18 and 41 stop their operation, and the swivel table 14 and work table 20 stop their rotation. In other words, the excavation mechanism 47 is
The excavating mechanism 47 receives the turning movement on the car body 10 and the turning movement in the opposite direction on the swivel table 14 of the work platform 20, resulting in double turning, and the excavation mechanism 47
When rotating from the front to the rear of the vehicle, the vehicle always rotates passing above the swivel base 14, and the excavation mechanism 47 rotates within the maximum range so as not to protrude to the side of the vehicle body 10. . To reverse the excavation mechanism 47 from the position C to the position A in FIG.
If you rotate it 180 degrees, it will perform the same operation as above,
The turning table 14 and the work table 20 are rotated at a constant ratio.

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. Further, even if the width of the road is approximately the same as the width of the vehicle body, the bucket and the like do not protrude from the vehicle body, so work can be carried out even under narrow usage conditions. The swivel table and the work table are rotated by separate hydraulic motors, and the rotation angle position of both is detected by a rotation angle detection means, and the rotation angle of both is controlled to be a constant ratio, so it is smooth and smooth. Since the excavation mechanism always passes over the swivel table and does not require a complicated mechanical interlocking mechanism, unnecessary stress and energy loss can be minimized.

[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 rotation order. DESCRIPTION OF SYMBOLS 10...Vehicle body, 14...Swivel table, 20...Work table, 18, 41...Hydraulic motor, 47...Excavation mechanism, 45, 47...Angle detector.

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. Both signals of the angle detection means are transmitted to the signal processing means, and the operation of the two hydraulic motors is controlled based on the result of calculation processing by the signal processing means, thereby controlling the swivel table and the work table which are rotated by the two hydraulic motors. A control mechanism for an excavator that operates while maintaining a rotational angular velocity at a predetermined ratio.