Control device for grip-type hole-digging and pole-setting vehicle

Abstract

To provide a control device of a gripping-type hole digging and pole erecting vehicle capable of expanding applications of a gripping device.SOLUTION: A gripping-type hole digging and pole erecting vehicle comprises: a boom provided on a vehicle body; a gripping portion having a pair of gripping claws that can be opened and closed for gripping a columnar object; a support mechanism that changes a posture of the gripping portion with respect to a tip of the boom; a column extractor that pulls out the columnar object placed on the ground according to expansion and contraction operations of a column extractor cylinder 41; and an operation control portion 102 that controls operations of the boom, the gripping portion, the support mechanism, and the column extractor according to operations of an operation device 31. The operation control portion 102 can pull out the columnar object placed on the ground using the column extractor by extending the column extractor cylinder 41 in a state where the gripping of the columnar object by the gripping portion is relaxed.SELECTED DRAWING: Figure 11

Description

[Technical Field]

[0001] The present invention relates to a control device for a gripping-type pole-digging vehicle equipped with a gripping device for gripping, for example, a pole-shaped object. [Background technology]

[0002] A known pole hole digger, a type of work vehicle, is a gripping-type pole hole digger, which includes a swivel base mounted on the vehicle body for free rotation, a boom mounted on the swivel base for free extension and retraction, an auger device attached to the boom for digging a pole hole for installing a utility pole, and a gripping device attached to the tip of the boom for gripping a pole-shaped object such as a utility pole (see, for example, Patent Document 1). When using this gripping-type pole hole digger to excavate a pole hole in the ground, the auger device is suspended from the tip of the boom and the boom is operated as needed, and the auger device is rotated at a predetermined excavation position to form a pole hole of a predetermined depth. After the excavation of the pole hole is completed, the auger device is raised and stored on the side of the boom, and the utility pole is gripped by the gripping device attached to the tip of the boom. With the utility pole gripped, the boom is operated as needed to directly install the utility pole into the excavated pole hole. This type of gripping-type hole-digging pole erection vehicle allows the entire pole erection process to be carried out more efficiently than when the pole is suspended using a winch or crane. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Unexamined Patent Publication No. 2-81892 Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, however, there has been a demand for the use of the gripping device of a gripping-type hole-digging pole erection vehicle to be expanded beyond its original purpose of pole erection work to other uses.

[0005] The present invention has been made in consideration of such problems, and aims to provide a control device for a gripping-type hole-digging pole-setting vehicle that can expand the uses of the gripping device. [Means for solving the problem]

[0006] In order to solve the above problems, the control device of the gripping-type pole digging vehicle of the present invention comprises a boom that is mounted on the vehicle body and can be raised and lowered and extended, a gripping unit having a pair of openable and closable gripping claws for gripping a pole-shaped object, a support mechanism that is mounted between the tip of the boom and the gripping unit and changes the attitude of the gripping unit relative to the tip of the boom, a pole extractor that extracts a pole-shaped object placed on the ground in accordance with the extension and retraction of a pole extractor cylinder, an operating device that controls the operation of the boom, the gripping unit, the support mechanism, and the pole extractor, and an operation control unit that controls the operation of the boom, the gripping unit, the support mechanism, and the pole extractor in accordance with the operation of the operating device, and is characterized in that the operation control unit is configured to extend the pole extractor cylinder while the grip of the pole object by the gripping unit is relaxed, thereby allowing the pole extractor to extract a pole that has been placed on the ground.

[0007] In the control device of the gripping type pole digging vehicle having the above-mentioned configuration, the operation control section performs a first operation of loosening the grip of a pole-like object placed on the ground from a state where the pole is gripped by the gripping section to a degree that the pole does not fall off and extending the pole extraction cylinder to pull the pole out of the ground, a second operation of gripping the pole again by the gripping section to hold the pole, and a third operation of controlling the gripping section to pull the pole out of the ground. It is preferable that the holding portion is configured to be able to continuously perform a third operation of retracting the column-removing cylinder while holding a column-shaped object.

[0008] In addition, in the control device of the grip-type pole digging vehicle configured as described above, the operating device has a continuous operation operating device for continuously performing the first operation to the third operation, and the operation control unit is configured to be able to continuously perform the continuous operations from the first operation to the third operation multiple times in accordance with the operation of the continuous operation operating device, and is equipped with a pressure detector for detecting the pressure in the extension side oil chamber of the pole extraction cylinder, and when the continuous operations are performed multiple times, it is preferable that the operation control unit starts the extension operation of the pole extraction cylinder for the first operation from the second time onwards among the multiple times, and releases the grip of the gripping unit when the pressure in the extension side oil chamber detected by the pressure detector reaches a predetermined value. [Effects of the Invention]

[0009] According to the control device of the gripping-type hole-digging pole-setting vehicle of the present invention, there is no need to use large heavy equipment such as a crane to lift the utility pole to be removed.The gripping device of this gripping-type hole-digging pole-setting vehicle can be used to appropriately switch between gripping and releasing (relaxing the grip) the column-shaped object to be removed, and pole removal work can be performed using a pole removal machine.This means that different types of work (pole installation work and pole removal work) can be performed with a single gripping-type hole-digging pole-setting vehicle, expanding the uses of the gripping device and further increasing the added value of this gripping-type hole-digging pole-setting vehicle. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 2 is a side view of the gripping-type hole-digging pole-setting vehicle according to the present embodiment. [Figure 2] FIG. 2 is a plan view of the above-mentioned gripping-type hole digging and pole erection vehicle. [Figure 3] FIG. 2 is a side view showing the use state of the above-mentioned grip-type hole digging pole erection vehicle. [Figure 4] FIG. 2 is a perspective view of an auger device provided on the grip-type hole digging pole erection vehicle. [Figure 5] FIG. 2 is a perspective view of a gripping device provided on the gripping-type hole-digging pole-setting vehicle. [Figure 6] FIG. 2 is a perspective view of the main part of the gripping device as seen from the right. [Figure 7]FIG. 2 is a perspective view of the main part of the gripping device as seen from the left. [Figure 8] FIG. 2 is a cross-sectional view of the gripping device. [Figure 9] FIG. 2 is a longitudinal sectional view of the gripping device. [Figure 10] This is a side view of a pole extraction device provided on the above-mentioned gripping-type hole digging and pole erection vehicle. [Figure 11] FIG. 2 is a functional block diagram of the above-mentioned gripping-type hole digging pole erection vehicle. [Figure 12] 10A and 10B are schematic diagrams for explaining an operation of setting the gripping portion of the gripping device in a horizontal position. [Figure 13] 10 is a conceptual diagram for explaining the relationship between a load acting on the gripping portion and the amount of displacement when the gripping portion is moved vertically downward. FIG. [Figure 14] FIG. 2 is a schematic diagram showing the excavation work of the above-mentioned gripping-type hole digging pole erection vehicle. [Figure 15] This is a schematic diagram showing the operation of the gripping part when the automatic vertical switch provided on the above-mentioned gripping-type hole-digging pole erection vehicle is operated. [Figure 16] 10 is a schematic diagram illustrating the direction of the load acting on the gripping portion during the process of inserting the utility pole held by the gripping portion into a pole hole. FIG. [Figure 17] FIG. 2 is a schematic diagram showing the flow of an automatic pole removal operation using the pole removal device. [Figure 18] FIG. 17 is a schematic diagram showing the flow of automatic pole erection work using the pole extraction device (continuation of FIG. 17). [Figure 19] FIG. 18 is a schematic diagram showing the flow of automatic pole erection work using the pole extraction device (continuation of FIG. 18). DETAILED DESCRIPTION OF THE INVENTION

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will now be described with reference to the drawings. First, the overall configuration of a grip-type hole digging pole erection vehicle 1 according to this embodiment will be described with reference to FIGS.

[0012] As shown in Figure 1, the grip-type hole-digging and pole-setting vehicle 1 has a driver's cabin 7 at the front of the vehicle body 2, and is constructed based on a truck vehicle that can travel on a pair of left and right tires and wheels 5 arranged at the front and rear of the vehicle body 2. Jacks 9 for lifting and supporting the vehicle body 2 are arranged at four locations on the front, rear, left and right of the vehicle body 2. Each jack 9 lifts and supports the vehicle body 2 by driving a jack cylinder (not shown) installed inside it and extending it downward, thereby stabilizing the entire vehicle body 2. The jacks 9 are operated by operating a jack operating device (not shown) installed at the rear of the vehicle body 2.

[0013] A swivel base 12 driven by a swivel motor 14 (see FIG. 11) and configured to be horizontally rotatable about a vertical axis is provided in the mounting area behind the driver's cabin 7 of the vehicle body 2. The base end of a boom 13 is attached to the swivel base 12 so as to be vertically swingable (raise and lower).

[0014] The boom 13 has a configuration in which, from the swivel base 12 side, a base boom 13a, an intermediate boom 13b, and a tip boom 13c are nested together, and the boom 13 can be extended and retracted in the axial direction (longitudinal direction) by the extension and retraction of a telescopic cylinder 15 (see Figure 11) installed inside. In addition, a derricking cylinder 16 is installed between the base boom 13a and the swivel base 12, and by extending and retracting this derricking cylinder 16, the entire boom 13 can be raised and lowered in the vertical plane.

[0015] An auger support 17 is attached to the boom 13, and can be selectively connected to the base boom 13a and the tip boom 13c. As shown in FIG. 4, an upper shaft 27a of a connecting rod member 27 is pivotally connected to the auger support 17 so as to be swingable left and right. An auger device 20 for drilling post holes is pivotally connected to a lower shaft 27b of the connecting rod member 27 so as to be swingable forward and backward. The auger device 20 includes an auger motor unit 21 pivotally connected to the lower shaft 27b of the connecting rod member 27 and an auger screw (earth auger) 25 that is rotated about its axis by operating the auger motor unit 21. The auger motor unit 21 includes an auger motor 22 that is hydraulically rotated, an auger reducer 23 connected to the output shaft of the auger motor 22, and an auger housing 24 that houses the auger motor 22 and the auger reducer 23. A drive shaft (not shown) of the auger reducer 23 protrudes from the lower end of the auger housing 24, and the upper end of the auger screw 25 is connected to this drive shaft.

[0016] Additionally, an auger storage device 18 that holds the auger device 20 in a stored state is disposed on the side of the base boom 13a. The auger device 20 is attached to the auger support 17 via a connecting rod member 27 so as to be able to swing up and down in a vertical plane, and can be swung between a stored position in which the auger device 20 is stored along the side of the base boom 13a by the auger storage device 18, and a working position in which the auger device 20 is removed from the auger storage device 18 and the auger screw 25 hangs down toward the ground. Note that when the auger device 20 is in the working position, it is suspended from the tip of the boom 13 so as to be able to swing freely in the front-to-rear and left-to-right directions around both shafts 27a, 27b of the connecting rod member 27 as fulcrums, so that the auger screw 25 assumes a vertical position aligned with the direction of gravity (vertical direction) regardless of the attitude of the boom 13.

[0017] When using the auger device 20, as shown in I of Figure 3, the auger support 17 is connected to the tip boom 13c, and the auger device 20 is detached from the auger storage device 18 and swung to the working position (with the auger screw 25 in a position approximately vertical to the ground), and the auger screw 25 is rotated by the rotational drive of the auger motor 22 while the boom 13 is lowered and retracted in conjunction with each other to move linearly downward, thereby enabling the excavation of a post hole. On the other hand, when the auger device 20 is not in use, as shown in II of Figure 3, the auger support 17 is connected to the tip boom 13c, and the auger device 20 is detached from the auger storage device 18 and swung to the working position (with the auger screw 25 in a position approximately vertical to the ground), and the auger screw 25 is rotated by the rotational drive of the auger motor 22 while the boom 13 is lowered and retracted in conjunction with each other to move linearly downward, thereby enabling the excavation of a post hole. The auger support 17 is connected to the base boom 13a, and the auger device 20 is stored and held in a storage position along the side of the base boom 13a by the auger storage device 18. When the auger device 20 is in the storage position, various operations can be performed using the gripping device 50 described below, such as erecting and removing utility poles (indicated by the symbol P in FIG. 3; the same applies hereinafter) and relocating obstacles.

[0018] An arm bracket 19 is fixed to the tip of the tip boom 13c. A gripping device 50 is attached to this arm bracket 19, which grips an object (pillar-shaped object) such as a utility pole or a tree. The configuration of this gripping device 50 will be described with additional reference to Figures 5 to 9. Note that hatching indicating cross sections has been omitted in Figures 8 and 9 to make the drawings easier to see. Furthermore, for ease of explanation, the directions of the illustrated front-rear, left-right, and up-down arrows will be referred to as the front-rear direction, left-right direction, and up-down direction, using the attitude of the gripping device 50 shown in Figure 5 as a reference.

[0019] The gripping device 50 is configured to include an arm 51 attached to the arm bracket 19 so as to be able to swing (bend and stretch) in the vertical direction, a first joint member 60 attached to the tip of the arm 51 so as to be able to swing (pivot vertically) in the vertical direction, a second joint member 70 attached to the first joint member 60 so as to be able to swing (pivot horizontally) in the left-right direction, and a gripper 80 rotatably attached to the second joint member 70. In this embodiment, a support mechanism that changes the posture of a gripping portion 81 of the gripper 80 is configured by the arm 51, the first joint member 60, the second joint member 70, a vertical pivot cylinder 62, a horizontal pivot cylinder 71, a gripper motor 79, etc., which will be described later.

[0020] One end of the arm 51 in the axial direction (longitudinal direction) is pivotally connected to the arm bracket 19 via a connecting pin 52, and the other end of the arm 51 in the axial direction (longitudinal direction) is pivotally connected to the first joint member 60 via a connecting pin 53. Arm 51 An arm cylinder 55 is attached between the arm bracket 19 and the arm cylinder 55. The rod side end of the arm cylinder 55 is pivotally connected to the arm bracket 19 via a connecting pin 56. The bottom side end of the arm cylinder 55 is Tip side of arm 51 The arm 51 is pivotally connected to the arm bracket 19 via a connecting pin 57. By extending and contracting the arm cylinder 55, the arm 51 can be freely swung (flexed and extended) in the vertical direction around the connecting pin 52 relative to the arm bracket 19.

[0021] The first joint member 60 is bifurcated, with the tip end open, and the second joint member 70 is pivotally connected to both ends of the bifurcated member via a pair of upper and lower connecting pins 61. A vertical oscillating cylinder 62 is provided between the first joint member 60 and the arm 51. The bottom end of the vertical oscillating cylinder 62 is pivotally connected to the base end of the arm 51 via a connecting pin 63. The rod end of the vertical oscillating cylinder 62 is pivotally connected to the upper end of the first joint member 60 via a connecting pin 64. By extending and retracting the vertical oscillating cylinder 62, the first joint member 60 can be freely swung (vertically oscillated) in the up and down direction relative to the arm 51 around the connecting pin 53.

[0022] The second joint member 70 is supported by the first joint member 60 so as to be sandwiched from above and below. A horizontally oscillating cylinder 71 is provided at the upper end of the first joint member 60. The horizontally oscillating cylinder 71 has a bottom end pivotally connected to the tip of the first joint member 60 and a rod end pivotally connected to the rear end of the second joint member 70. By extending and contracting this horizontally oscillating cylinder 71, the second joint member 70 can be freely oscillated left and right (horizontally oscillated) relative to the first joint member 60 around the connecting pin 61.

[0023] The gripper 80 has a gripping portion 81 that grips an object, and a second joint that supports the gripping portion 81. The gripper housing 86 is rotatably mounted on the support member 70, and an opening / closing mechanism 93 that opens and closes the gripping portion 81.

[0024] The gripping unit 81 includes a pair of gripping claws 82 and a pair of upper and lower support plates 83 that support the pair of gripping claws 82 so that they can open and close in directions that move them toward or away from each other (opening and closing directions). The gripping claws 82 are configured to be able to grip various objects (pillar-shaped objects), such as utility poles and trees. The base ends of the gripping claws 82 are pivotally connected to the upper and lower support plates 83 via connecting pins 84. Alternating notches 82a and 82b are formed in the tips of the gripping claws 82, and these tips are configured to be able to intersect (overlap) with each other. The support plate 83 is provided with a flat upper bracket 85 for detachably mounting an attachment (not shown) (for example, a tree felling device for felling trees).

[0025] The gripper housing 86 includes a support cylinder portion 87 connected to the upper and lower support plate portions 83 and rotatably supported on the second joint member 70, and a cylinder bracket portion 92 fixed to the base end side of the support cylinder portion 87 and disposed between the first joint member 60 and the second joint member 70.

[0026] The support cylinder 87 has a double structure including an inner cylinder 88 formed in the shape of a hollow rectangular cylinder and an outer cylinder 89 formed in the shape of a hollow cylinder and provided on the outer periphery of the inner cylinder 88. A sliding member 95 of an opening / closing mechanism 93 (described later) is attached to the inner periphery of the inner cylinder 88 so as to be slidable in the front-rear direction. A worm wheel 90 is attached to the outer periphery of the outer cylinder 89 concentrically with the outer cylinder 89. The worm wheel 90 meshes with a worm pinion 91 rotatably supported inside the second joint member 70. A gripper motor 79 is attached to the upper end of the second joint member 70, and the worm pinion 91 is connected to the output shaft of the gripper motor 79 via a reducer. When the gripper motor 79 is rotated in the forward direction, the entire gripper 80 rotates in a predetermined direction around the rotation axis X (see FIG. 8) via the worm pinion 91 and the worm wheel 90. On the other hand, when the gripper motor 79 is rotated in the reverse direction, the entire gripper 80 rotates in the opposite direction to the predetermined direction around the rotation axis X (see FIG. 8) via the worm pinion 91 and the worm wheel 90. In the posture of the gripping device 50 shown in FIG. 5, the direction of the rotation axis X of the gripper 80 (gripping portion 81) corresponds to the front-rear direction, and the opening / closing direction (gripping direction) of the gripping portion 81 corresponds to the left-right direction.

[0027] The opening / closing mechanism 93 includes a pair of link members 94, a sliding member 95 linked and connected to the pair of link members 94, and a gripper cylinder 99 that slides the sliding member 95 back and forth. One end of each link member 94 is pivotally connected to an intermediate portion of the gripping jaw 81 via a connecting pin 96. The pair of link members 94 are pivotally connected to the tip end of the sliding member 95 via a connecting pin 97 with the other end of each link member 94 stacked vertically. The sliding member 95 is inserted into the hollow portion of the inner cylindrical portion 88 and is attached so as to be slidable (reciprocating) along the inner circumferential surface of the inner cylindrical portion 88. A slider 98 made of synthetic resin is attached between the outer circumferential surface of the sliding member 95 and the inner circumferential surface of the inner cylindrical portion 88 to guide the sliding (reciprocating movement) of the sliding member 95. The rod side end of the gripper cylinder 99 is connected to the base end of the sliding member 95. The bottom end of the gripper cylinder 99 is connected to the cylinder bracket portion 92 of the gripper housing 86. When the gripper cylinder 99 is extended, the sliding member 95 slides in the extension direction, causing the link members 94 to swing in directions away from each other. This causes the gripping claws 82 to swing in the opening direction around the connecting pin 84 as a fulcrum (the gripping claws 82 operate in the opening direction (opening operation)), thereby releasing the grip of the object. On the other hand, when the gripper cylinder 99 is retracted, the sliding member 95 slides in the retraction direction, causing the link members 94 to swing in directions approaching each other. This causes the gripping claws 82 to swing in the closing direction around the connecting pin 84 as a fulcrum (the gripping claws 82 2 is operated in the closing direction (closing operation), the object can be grasped. Note that since the opening and closing mechanism 93 is configured symmetrically, the pair of gripping claws 82 are opened and closed symmetrically.

[0028] An operator's seat 30 for operating each of the work devices (the swivel 12, the boom 13, the auger device 20, and the gripping device 50) is provided on the side of the swivel 12 of the vehicle body 2. In front of the operator's seat 30 is provided an operating device 31 that can be operated by an operator while remaining seated. As shown in FIG. 11, the operating device 31 is provided with a boom rotation / hoisting operation lever 32a for rotating and raising the boom 13, a boom extension / retraction operation lever 32b for extending and retracting the boom 13 and bending and extending the arm 51, an auger operation lever 32c for rotating the auger screw 25, a gripper vertical swing operation lever 32d for vertically swinging the gripper 81, a gripper horizontal swing operation lever 32e for horizontally swinging the gripper 81, a gripper rotation operation lever 32f for rotating the gripper 81, and a gripper opening / closing operation lever 32g for opening and closing the gripper 81.

[0029] The operating device 31 is also provided with a pole extractor operating lever 32h for operating the pole extractor 40 (pulling out the utility pole), which is used as an optional hydraulic device. As shown in Fig. 10, the pole extractor 40 comprises a hydraulically retractable pole extractor cylinder 41, a sole plate 44 attached to the lower end of the pole extractor cylinder 41 and grounded to the ground, and a chain 45 attached to the upper end of the pole extractor cylinder 41 and wound around the utility pole (indicated by symbol P in Fig. 10). The pole extractor cylinder 41 comprises a cylinder tube 42 and a piston rod 43 attached to the cylinder tube 42 so as to be able to extend and retract vertically. Both ends of the chain 45 are detachably attached to the upper end of the cylinder tube 42 of the pole extractor cylinder 41. The chain 45 is formed to a length that allows it to be wound around the outer periphery of the utility pole several times. A bottom plate 44 is pivotally connected to the lower end of the piston rod 43 so as to be swingable around a support shaft 44a (so that it can swing according to the slope and unevenness of the ground). A hydraulic hose 46 connected to a bottom-side oil chamber of the cylinder tube 42 and a hydraulic hose 47 connected to a rod-side oil chamber of the cylinder tube 42 are connected to the pole extractor cylinder 41. These hydraulic hoses 46, 47 are connected to a pole extractor hydraulic outlet (not shown) provided on the vehicle body 2 with a seal coupling (one-touch joint). By connecting these hydraulic hoses 46, 47 to a pole extractor hydraulic outlet (not shown) provided on the vehicle body 2 with a seal coupling (one-touch joint), the oil chambers (bottom-side oil chamber, rod-side oil chamber) of the pole extractor cylinder 41 communicate with the ports of the electromagnetic proportional control valve V10 via this pole extractor hydraulic outlet, enabling the supply and discharge of hydraulic oil (pressurized oil) between the pole extractor cylinder 41 and the electromagnetic proportional control valve V10.

[0030] As shown in FIG. 11, the operating device 31 is provided with a mode selection switch 33, an automatic vertical switch 34, and an automatic column removal switch 35.

[0031] The mode selection switch 33 is configured as a toggle switch that can be switched between a neutral position, a forward position, and a rearward position (it is configured to maintain the selected operating position even if the operator releases the switch). When the mode selection switch 33 is in the neutral position, the normal mode is selected; when the mode selection switch 33 is in the forward position, the vertical auger operation mode is selected; and when the mode selection switch 33 is in the rearward position, the vertical gripper operation mode is selected. The normal mode is a mode in which the hydraulic actuators are operated independently in response to the operation of the operation levers 32a to 32h to individually perform the lifting, retracting, and swinging of the boom 13, the rotation of the auger device 20 (auger screw 25), the bending and extending of the arm 51, the vertical swing, horizontal swing, rotation, and opening / closing of the gripper 81, and the extension and retraction of the pole extractor 40. The vertical auger operation mode is a mode in which the boom hoisting cylinder 16 and the telescopic cylinder 15 are operated in combination (linked operation) in response to the operation of the boom swing / hoisting operation lever 32a, thereby moving the auger device 20 (the tip of the boom 13) in the vertical direction (up and down). In this mode, the boom hoisting cylinder 16, the telescopic cylinder 15, and the vertical swing cylinder 62 are operated in combination (linked operation) in response to the operation of the boom rotation / hoisting operation lever 32a, thereby moving the gripping part 81 vertically (up and down).

[0032] Automatic vertical switch 34 is configured as a toggle switch that can be switched between an ON position and an OFF position (it is configured to maintain the switched operating position even if the operator releases his / her hand). When automatic vertical switch 34 is selected to the ON position, as will be described in detail later, it operates vertical swing cylinder 62 and gripper motor 79 to vertically swing and rotate gripper unit 81, thereby making gripper unit 81 horizontal (i.e., making the utility pole gripped by gripper unit 81 vertical). Note that operation of automatic vertical switch 34 is valid (the operation signal is validly received) when the tilt angle of gripper unit 81 with respect to the horizontal plane, detected by gripper tilt angle detector 124 (see FIG. 11), described later, is within a predetermined angle.

[0033] The automatic pole removal switch 35 is configured as a toggle switch that can be switched between an ON position and an OFF position (it is configured to maintain the switched operating position even if the worker releases his / her hand from the switch). When the automatic pole removal switch 35 is selected to the ON position, as will be described in detail later, the gripper cylinder 99 and the pole removal machine cylinder 41 are operated in conjunction with each other, and the opening and closing operation of the gripping part 81 is combined with the extension and contraction operation of the pole removal machine 40, so that the pole removal work of pulling the existing utility pole out of the ground can be performed automatically.

[0034] Here, as shown in FIG. 11, the operating mechanisms of the swivel base 12, boom 13, auger device 20, gripping device 50, pole extractor 40, etc. are configured with a controller 100 that receives operation signals from an operating device 31 and controls the swivel motor 14, telescopic cylinder 15, hoisting cylinder 16, auger motor 22, arm cylinder 55, vertical swing cylinder 62, horizontal swing cylinder 71, gripper motor 79, gripper cylinder 99, and pole extractor cylinder 41 (hereinafter collectively referred to as "hydraulic actuators"), and a hydraulic unit 110 that supplies hydraulic oil to drive these hydraulic actuators.

[0035] An operation signal output by operating the operation device 31 is input to the controller 100. The controller 100 outputs a command signal corresponding to the operation signal to the hydraulic unit 110 (control valve 112).

[0036] The hydraulic unit 110 is composed of a hydraulic pump 111 that discharges hydraulic oil and a control valve 112 that controls the supply direction and amount of hydraulic oil supplied from the hydraulic pump 111 to each hydraulic actuator. The hydraulic pump 111 is driven by power extracted from the vehicle's engine via a PTO mechanism (not shown). The control valve 112 includes an electromagnetic proportional control valve V1 corresponding to the swing motor 14, an electromagnetic proportional control valve V2 corresponding to the telescopic cylinder 15, an electromagnetic proportional control valve V3 corresponding to the hoisting cylinder 16, an electromagnetic proportional control valve V4 corresponding to the auger motor 22, an electromagnetic proportional control valve V5 corresponding to the arm cylinder 55, an electromagnetic proportional control valve V6 corresponding to the vertical swing cylinder 62, an electromagnetic proportional control valve V7 corresponding to the horizontal swing cylinder 71, an electromagnetic proportional control valve V8 corresponding to the gripper motor 79, an electromagnetic proportional control valve V9 corresponding to the gripper cylinder 99, and an electromagnetic proportional control valve V10 corresponding to the pole extractor cylinder 41. Based on a command signal from the controller 100, this control valve 112 electromagnetically drives the spools of each electromagnetic proportional control valve V1 to V10 to control the supply direction and amount of hydraulic oil supplied from the hydraulic pump 111 to each hydraulic actuator, and controls the operating direction and operating speed of each hydraulic actuator (controlling the operating direction and operating speed of the swivel base 12, boom 13, auger device 20, gripping device 50, and pole extractor 40).

[0037] The controller 100 includes a boom hoisting angle detector 120, a boom extension amount detector 121, Various detectors such as a boom rotation angle detector 122, an auger inclination angle detector 123, a gripper inclination angle detector 124, a gripper load detector 125, a gripper cylinder pressure detector 126, and column extractor cylinder pressure detectors 127 and 128 are electrically connected.

[0038] The boom hoisting angle detector 120 is provided inside the boom base end 13a and detects the hoisting angle of the boom 13. The boom extension amount detector 121 is provided at the base end of the boom base end 13a and detects the length (extension amount) of the boom 13. The boom rotation angle detector 122 is provided on the vehicle body 2 and detects the rotation angle of the boom 13 (rotating unit 12).

[0039] The auger inclination angle detector 123 is attached to the top of the auger motor unit 21 (auger housing 24). This auger inclination angle detector 123 detects the inclination angle of the auger device 20 (auger screw 25). As described above, the auger device 20 is suspended from the tip of the boom 13 around both shafts 27a, 27b of the connecting rod member 27 as fulcrums so that the auger screw 25 maintains a vertical position along the direction of gravity (vertical direction) regardless of the position of the boom 13. Therefore, when the auger device 20 is excavating a post hole (indicated by the symbol "K" in FIG. 14) using the auger device 20, if the excavation resistance of the ground is high, the axis of the auger screw 25 may tilt in the front-rear and left-right directions relative to the vertical line (vertical direction). The auger inclination angle detector 123 is configured as a two-axis inclination angle detector that detects the inclination angle in the left-right direction (X-axis direction) and the inclination angle in the front-back direction (Y-axis direction) of the auger screw 25 as the inclination angle of the auger screw 25 with respect to the vertical direction. The auger inclination angle detector 123 detects the inclination angle in the left-right direction and the inclination angle in the front-back direction of the auger screw 25 and outputs a voltage signal (detection signal) corresponding to the detected inclination angle to the controller 100.

[0040] The gripping unit tilt angle detector 124 is attached to the upper surface of the gripping unit 81 (support plate 83). The gripping unit tilt angle detector 124 is a two-axis tilt angle detector that detects the tilt angle in the left-right direction (X-axis direction) and the tilt angle in the front-back direction (Y-axis direction) as the tilt angle of the gripping unit 81 with respect to the horizontal plane. The gripping unit tilt angle detector 124 detects the tilt angle in the left-right direction and the tilt angle in the front-back direction of the gripping unit 81, and outputs a voltage signal (detection signal) corresponding to the detected tilt angle to the controller 100.

[0041] The gripper load detector 125 is a so-called pin-type load cell, and is configured as the connecting pin 63 that pivotally connects the bottom end of the vertical swing cylinder 62 and the base end of the arm 51. The gripper load detector 125 detects a load acting in the axial direction (the axial direction of the vertical swing cylinder 62) from the vertical swing cylinder 62 to the connecting pin 63, and outputs a voltage signal (detection signal) corresponding to the detected load to the controller 100. The load detected by the gripper load detector 125 (the load acting on the connecting pin 62) is proportional to the load acting on the gripper 81 (the load received by the gripper 81 in a vertical plane). Therefore, as will be described in detail later, the controller 100 determines the load acting on the gripper 81 based on the load detected by the gripper load detector 125.

[0042] The gripper cylinder pressure detector 126 detects the pressure of the electromagnetic proportional control valve V9 and the gripper cylinder 99. rod The gripper cylinder 99 is provided in the oil passage connecting the side oil chamber. rod The pressure of the hydraulic oil supplied to the side oil chamber ( rod The gripper cylinder pressure detector 126 detects the pressure of the gripper cylinder 99. rod The pressure in the side oil chamber is detected, and a voltage signal (detection signal) corresponding to the detected pressure is output to the controller 100. The pressure detected by this gripper cylinder pressure detector 126 is proportional to the gripping force of the gripper 81 (the force with which the gripper 81 grips an object). Therefore, as will be described in detail later, the controller 100 determines the gripping force of the gripper 81 based on the pressure detected by this gripper cylinder pressure detector 126.

[0043] The column extractor cylinder pressure detector 127 is provided in an oil passage connecting the electromagnetic proportional control valve V10 and the bottom-side oil chamber of the column extractor cylinder 41, and detects the pressure of the hydraulic oil supplied to the bottom-side oil chamber of the column extractor cylinder 41 (the pressure of the bottom-side oil chamber). In addition, the column extractor cylinder pressure detector 128 is provided in an oil passage connecting the electromagnetic proportional control valve V10 and the rod-side oil chamber of the column extractor cylinder 41, and detects the pressure of the hydraulic oil supplied to the rod-side oil chamber of the column extractor cylinder 41 (the pressure of the rod-side oil chamber). These column extractor cylinder pressure detectors 127, 128 detect the pressure of the hydraulic oil supplied to each oil chamber (bottom-side oil chamber, rod-side oil chamber) of the column extractor cylinder 41, and output a voltage signal (detection signal) corresponding to the detected pressure to the controller 100. In this embodiment, the stroke end of the column extractor cylinder 41 in the extension / retraction direction is detected based on the pressure detected by the column extractor cylinder pressure detectors 127, 128.

[0044] The controller 100 includes a position calculation unit 101, an operation control unit 102, an auger inclination determination unit 103, a grip determination unit 104, an automatic vertical control unit 105, a load determination unit 106, and an automatic column removal control unit 107.

[0045] The position calculation unit 101 calculates the position of the tip of the boom 13 relative to the vehicle body 2 based on the detection information from the boom hoisting angle detector 120 , the boom extension amount detector 121 , and the boom rotation angle detector 122 .

[0046] The operation control section 102 controls the operation of each actuator in accordance with the operation signal (operation command) output from the operation device 31, based on the operation mode selected by the mode selection switch 33. Each operation mode will be described below.

[0047] (Normal mode) When the mode selector switch 33 is set to the normal mode and the control levers 32a-32h are operated, the operation control unit 102 independently operates each hydraulic actuator in response to the operation of each control lever 32a-32h. Specifically, when the boom rotation / hoisting control lever 32a is tilted forward (in the front-to-back, left-to-right, and right-to-left directions relative to the operator operating it; the same applies below), the operation control unit 102 retracts the hoisting cylinder 16 to lower the boom 13, and when the boom rotation / hoisting control lever 32a is tilted backward, the operation control unit 102 extends the hoisting cylinder 16 to raise the boom 13. In addition, when the boom extension / retraction control lever 32b is tilted forward, the telescopic cylinder 15 is extended to extend the boom 13, and when the boom extension / retraction control lever 32b is tilted backward, the operation control unit 102 retracts the telescopic cylinder 15 to retract the boom 13. Furthermore, when the boom swing / hoisting control lever 32a is tilted left, the swing motor 14 is rotated forward to swing the boom 13 counterclockwise, and when the boom swing / hoisting control lever 32a is tilted right, the swing motor 14 is rotated reverse to swing the boom 13 clockwise. When the auger control lever 32c is tilted forward, the auger motor 22 is rotated reverse to rotate the auger screw 25 in the reverse direction, and when the auger control lever 32c is tilted backward, the auger motor 22 is rotated forward to rotate the auger screw 25 in the forward direction. When the boom extension / contraction control lever 32b is tilted left, the arm 51 is flexed and extended downward relative to the tip of the boom 13, and when the boom extension / contraction control lever 32b is tilted right, the arm 51 is flexed and extended upward relative to the tip of the boom 13. When the gripper vertical swing operation lever 32d is tilted forward, the vertical swing cylinder 62 is extended to swing the gripper 81 downward (vertical swing), and when the gripper vertical swing operation lever 32d is tilted backward, the vertical swing cylinder 62 is contracted to swing the gripper 81 upward (vertical swing). When the gripper horizontal swing operation lever 32e is tilted leftward, the horizontal swing cylinder 71 is extended. When the gripper rotation operation lever 32f is tilted forward, the gripper motor 79 is rotated forward to rotate the gripper 81 clockwise, and when the gripper rotation operation lever 32f is tilted backward, the gripper motor 79 is rotated backward to rotate the gripper 81 counterclockwise. Furthermore, when the gripper opening / closing operation lever 32g is tilted forward, the gripper cylinder 99 is contracted to operate the gripper 81 in the closing direction (direction to grip the object), and when the gripper opening / closing operation lever 32g is tilted backward, the gripper cylinder 99 is extended to operate the gripper 81 in the opening direction (direction to release the grip of the object). Furthermore, when the pole extractor operation lever 32h is tilted forward, the pole extractor cylinder 41 is extended to extend the pole extractor 40, and when the pole extractor operation lever 32h is tilted backward, the pole extractor cylinder 41 is contracted to operate the pole extractor 40.

[0048] (Auger vertical operation mode) Furthermore, when the mode selector switch 33 is set to the vertical auger operation mode and the boom swing / hoisting control lever 32a is operated, the operation control unit 102 combines and links the extension and retraction of the hoisting cylinder 16 and the telescopic cylinder 15 based on the position information (current position) of the tip of the boom 13 calculated by the position calculation unit 101, and moves the auger screw 25 (tip of the boom 13) in the vertical direction in accordance with the operation of the boom swing / hoisting control lever 32a. Specifically, when the boom swing / hoisting control lever 32a is tilted forward, the auger screw 25 is moved vertically downward by combining the retraction of the hoisting cylinder 16 and the retraction of the telescopic cylinder 15, and when the boom swing / hoisting control lever 32a is tilted backward, the auger screw 25 is moved vertically upward by combining the extension of the hoisting cylinder 16 and the extension of the telescopic cylinder 15.

[0049] (Grip vertical operation mode) Furthermore, when the mode selection switch 33 is set to the gripper vertical operation mode and the boom rotation / hoisting operation lever 32a is operated, the operation control unit 102 combines and links the extension / retraction operation of the hoisting cylinder 16, the extension / retraction operation of the telescopic cylinder 15, and the extension / retraction operation of the vertical swing cylinder 62 based on the position information (current position) of the tip of the boom 13 calculated by the position calculation unit 101 and the tilt angle of the gripper 81 detected by the gripper tilt angle detector 124, and moves the gripper 81 (the object gripped by the gripper 81) vertically in accordance with the operation of the boom rotation / hoisting operation lever 32a. Specifically, when the boom rotation / hoisting control lever 32a is tilted forward, the gripping part 81 moves vertically downward through a combination of the retraction of the boom hoisting cylinder 16, the retraction of the telescopic cylinder 15, and the retraction of the vertical swing cylinder 62, and when the boom rotation / hoisting control lever 32a is tilted backward, the gripping part 81 moves vertically upward through a combination of the extension of the boom hoisting cylinder 16, the extension of the telescopic cylinder 15, and the extension of the vertical swing cylinder 62. Specifically, the vertical operation control of the gripper 81 is performed by combining control to move the tip of the boom 13 in the vertical direction by combining the extension and contraction operation of the hoisting cylinder 16 and the extension and contraction operation of the telescopic cylinder 15 based on position information of the tip of the boom 13 calculated by the position calculation unit 101, and control to maintain the gripper 81 (rotation axis X of the gripper 81) in a horizontal state by the extension and contraction operation of the vertical swing cylinder 62 based on detection information detected by the gripper inclination angle detector 124 (the inclination angle of the gripper 81 with respect to the horizontal plane).

[0050] The auger inclination determination unit 103 determines the posture of the auger device 20 (auger screw 25) based on detection information from the auger inclination angle detector 123. Specifically, the auger inclination determination unit 103 compares the inclination angle of the auger screw 25 detected by the auger inclination angle detector 123 with a preset allowable angle (threshold angle), and determines the posture of the auger screw 25. The auger inclination determination unit 103 determines whether the inclination angle exceeds the allowable angle. The inclination angle of the auger screw 25 is the angle at which the axis of the auger screw 25 is inclined forward, backward, left, or right relative to the vertical direction. The allowable angle is set to, for example, 5 degrees (however, the setting can be changed as desired). Here, when an excavation operation is being performed in the vertical auger operation mode, combining the rotational operation and vertical lowering operation of the auger screw 25, if the auger inclination determination unit 103 determines that the inclination angle of the auger screw 25 is within the allowable angle, the auger inclination determination unit 103 permits the excavation operation. If the auger inclination determination unit 103 determines that the inclination angle of the auger screw 25 exceeds the allowable angle, the operation control unit 102 outputs a restriction signal to the operation control unit 102 to restrict the excavation operation. When the operation control unit 102 receives the restriction signal, the operation control unit 102 cuts off the control signal for rotating the auger screw 25 and vertically lowering the auger screw 25 from the control signal sent from the operation control unit 102 to the control valve 112, thereby forcibly stopping the excavation operation of the auger screw 25. This prevents the auger screw 25 from excavating at an angle greater than the allowable angle (forming an inclined post hole). Note that, while the excavation operation of the auger screw 25 (rotation and vertical lowering of the auger screw 25) is restricted, the operation of moving the auger screw 25 vertically upward from the post hole being excavated (vertical ascent of the auger screw 25) is permitted. Therefore, when the excavation operation of the auger screw 25 is restricted, the auger screw 25 can be moved vertically upward and temporarily withdrawn from the excavated hole, allowing the auger screw 25 to return to a vertical position (a position facing vertically downward) under its own weight. After returning the auger screw 25 to a vertical position, the auger screw 25 can be rotated and vertically lowered again to restart excavating the post hole being excavated (the same post hole) from the middle.

[0051] The grip determination unit 104 determines the gripping state of the gripper 81 based on detection information from the gripper cylinder pressure detector 126. Specifically, when the pressure detected by the gripper cylinder pressure detector 126 rises to or above a predetermined first threshold pressure, the grip determination unit 104 determines that the gripper 81 is gripping the utility pole (target object) (that the gripper 81 is gripping the utility pole with a specified gripping force). Furthermore, when the pressure detected by the gripper cylinder pressure detector 126 falls to or below a predetermined second threshold pressure (where the first threshold pressure is greater than the second threshold pressure), the grip determination unit 104 determines that the grip of the utility pole (target object) by the gripper 81 has loosened (that the gripping force has weakened to the extent that the utility pole will not fall off the gripper 81).

[0052] When automatic vertical switch 34 of operating device 31 is turned on, automatic vertical control unit 105 determines whether the tilt angle of grip unit 81 detected by grip unit tilt angle detector 124 is within a predetermined angle (for example, within 5 degrees). Here, automatic vertical control unit 105 stores an automatic vertical program, and if it determines that the tilt angle of grip unit 81 is within the predetermined angle when an operation signal is input from automatic vertical switch 34, it outputs a command signal to operation control unit 102 based on the detection information from grip unit tilt angle detector 124 in accordance with this automatic vertical program. When the operation control unit 102 receives a command signal from the automatic vertical control unit 105, it feeds back the tilt angle of the gripper unit 81 from the gripper unit tilt angle detector 124, and based on this fed-back information, it corrects the tilt of the gripper unit 81 in the front-to-rear direction by extending and contracting the vertical swing cylinder 62 until the tilt angle of the gripper unit 81 in the front-to-rear direction reaches the target angle (0 degrees), and also corrects the tilt of the gripper unit 81 in the left-to-right direction by rotating the gripper motor 79 until the tilt angle of the gripper unit 81 in the left-to-right direction reaches the target angle (0 degrees). Regarding the tilt of the gripper unit 81 in the front-to-rear direction, the gripper unit 81 can be tilted downward (see the Y1 direction in FIG. 12) by extending the vertical swing cylinder 62, and can be tilted upward (see the Y2 direction in FIG. 12) by contracting the vertical swing cylinder 62. Regarding the tilt of the gripper 81 in the left-right direction, the gripper motor 79 is rotated in the forward direction to tilt the gripper 81 to the left (see the Z1 direction in FIG. 12) around the rotation axis X, and the gripper motor 79 is rotated in the reverse direction to tilt the gripper 81 to the right (see the Z2 direction in FIG. 12) around the rotation axis X. ) in the horizontal position (see Fig. 1). In this way, based on a command from automatic vertical control unit 105, operation control unit 102 executes feedback control based on the deviation between the tilt angle of gripper 81 and the target angle (0 degrees), thereby putting gripper 81 in a horizontal position (putting the utility pole gripped by gripper 81 in a vertical position). Note that this automatic vertical control is used not only when gripper 81 is put in a horizontal position when gripper 81 is gripping a utility pole (i.e., when putting the utility pole gripped by gripper 81 in a vertical position), but also when gripper 81 is put in a horizontal position when gripper 81 is not gripping a utility pole (when gripper 81 is not gripping anything). As a variation thereof, automatic vertical control unit 105 may be configured to perform automatic vertical control only when grip determination unit 104 determines that gripper 81 is gripping a utility pole (target object).

[0053] The load determination unit 106 determines a change in the load acting on the gripping unit 81 based on the detection information from the gripping unit load detector 125. Here, FIG. 13 is a conceptual diagram showing the relationship between the load acting on the gripping unit 81 and the displacement when the gripping unit 81 is moved vertically downward. As shown in FIG. 13, when the gripping unit 81 is gripping a utility pole, a load corresponding to the weight of the utility pole acts downward on the gripping unit (A in the figure). At this time, when the gripping unit 81 is moved vertically downward and the lower end of the utility pole gripped by the gripping unit 81 reaches the bottom of the pole hole (B in the figure), the load acting on the gripping unit 81 decreases due to a reaction force from the bottom of the hole (a reaction force that tries to push the utility pole up). Then, after the load on the gripping unit 81 decreases to 0 (C in the figure), the direction of the load reverses from downward to upward (D in the figure). In this way, the timing when the utility pole abuts against the bottom of the hole corresponds to the timing when the direction of the load acting on the gripping unit 81 reverses (the timing when the load becomes 0). Therefore, when the load of the gripping unit 81 detected by the gripping unit load detector 125 during the vertical descent operation of the gripping unit 81 while the gripping unit 81 is gripping a utility pole drops to a threshold load ("0" in this embodiment), the load determination unit 106 determines that the utility pole gripped by the gripping unit 81 has abutted against the bottom of the pole hole. Then, when the load determination unit 106 determines that the load detected by the gripping unit load detector 125 has dropped to the threshold load (the object has abutted against the bottom of the pole hole), it outputs a restriction signal to the operation control unit 102 to restrict the vertical descent operation of the gripping unit 81 (vertical descent operation). When the operation control unit 102 receives a restriction signal from the load determination unit 106, it ignores the operation signal for vertically lowering the gripper 81 among the operation signals input by operating the operating device 31, or cuts off the control signal for vertically lowering the gripper 81 among the control signals sent from the operation control unit 102 to the control valve 112, thereby forcibly stopping the vertical lowering operation of the gripper 81 that had been performed up until then. As a result, even if any further operation to move the gripper 81 vertically downward (operation to move the utility pole downward) is performed, the vertically downward movement of the gripper 81 is restricted.In this way, the downward movement of the gripping portion 81 is restricted when the lower end of the utility pole abuts against the bottom (rear end) of the post hole, thereby preventing the lower end of the utility pole from being pressed excessively against the bottom of the hole.

[0054] When the automatic pole extraction switch 35 of the operating device 31 is turned on, the automatic pole extraction control unit 107 operates the gripping unit 81 and the pole extraction machine 40 in conjunction with each other to perform automatic pole extraction work to pull out an existing utility pole from the ground. This automatic pole extraction work includes a process of releasing (relaxing) the grip of the utility pole by the gripping unit 81 and extending the pole extraction machine 40, and a process of gripping the utility pole with the gripping unit 81 and retracting the pole extraction machine 40. Here, the automatic pole extraction control unit 107 stores an automatic pole extraction program, and when an operation signal is input from the automatic pole extraction switch 35, it outputs a command signal to the operation control unit 102 in accordance with this automatic pole extraction program based on detection information from the gripper cylinder pressure detector 126 and the pole extraction machine cylinder pressure detectors 127, 128, etc., and controls the opening and closing operation of the gripping unit 81 and the extension and retraction operation of the pole extraction machine 40 in conjunction with each other to continuously perform each process of the automatic pole extraction work. The details of the pole removal work (automatic pole removal work) of this embodiment will be described later.

[0055] Next, the operation of the grip-type hole digging pole erection vehicle 1 of this embodiment will be described. The excavation work, the pole erection work, and the pole removal work using the grip-type hole digging and pole erection vehicle 1 in this state will be described in order.

[0056] [1. Excavation work] First, we will explain the excavation work (hole digging work) of the grip-type hole digging pole erection vehicle 1. Figure 14 is a schematic diagram showing the excavation work by the auger device 20. In the following explanation, unless otherwise specified, it is assumed that the mode selection switch 33 is set to the normal mode.

[0057] When performing excavation work using the grip-type pole digger 1, first, the auger support 17 is connected to the tip boom 13c, and then the operating device 31 is operated to raise and lower the boom 13 by a predetermined angle (e.g., 60 degrees). In this state, the auger device 20 is removed from the auger storage device so that the auger device 20 is suspended vertically downward from the tip of the boom 13. Next, the operating device 31 is operated to raise, lower, extend, and rotate the boom 13, moving the auger screw 25 above the excavation position. Next, the mode selector switch 33 is switched from the normal mode to the vertical auger operation mode, and the auger screw 25 is moved vertically downward by linking the lowering and retracting of the boom 13 while rotating the auger screw 22, thereby digging vertically into the ground with the auger screw 25. At this time, as shown in FIG. 14 , if the ground being excavated is hard, the auger screw 25 (axis J) may tilt forward, backward, left, or right relative to the vertical direction due to an excavation reaction force (excavation resistance) from the ground. The inclination angle of the auger screw 25 is constantly detected by an auger inclination angle detector 123 provided on the upper surface of the auger device 20. Based on the detection information from the auger inclination angle detector 123, the auger inclination determination unit 103 of the controller 100 determines whether the inclination angle of the auger screw 25 exceeds the allowable angle. If the auger inclination determination unit 103 determines that the inclination angle of the auger screw 25 exceeds the allowable angle, it forcibly stops the rotation and vertical lowering of the auger screw 25 (restricts the excavation operation of the auger screw 25). When the excavation operation of the auger screw 25 is restricted in this way, the operator operates the operating device 31 to raise the auger screw 25 vertically, thereby pulling the auger screw 25 out of the ground (post hole). This allows the auger screw 25, under its own weight, to return to a state in which it is suspended vertically downward from the tip of the boom 13. Then, the auger screw 25 is rotated and lowered vertically again, and the auger screw 25 is reinserted into the post hole being excavated to re-dig the post hole, thereby forming a vertical post hole.

[0058] [2. Pole erection work] Next, we will explain the pole erection operation of the grip-type hole-digging pole erection vehicle. Figure 15 is a schematic diagram showing the operation of the gripper 81 when the automatic vertical switch 34 is operated, and Figure 16 is a schematic diagram for explaining the direction of the load acting on the gripper 81. Unless otherwise specified in the following explanation, it is assumed that the mode selection switch 33 is set to the normal mode.

[0059] When performing pole erection work using the gripping-type hole-digging pole erection vehicle 1, first, the operating device 31 is operated to appropriately operate the boom 13, and the arm 51 is bent and extended, and the gripping unit 81 is swung vertically, horizontally, and rotated, etc., to move the gripping unit 81 close to a utility pole (for example, a utility pole placed horizontally at a work site) and align the gripping unit 81 with the utility pole. Next, the pair of gripping claws 82 are operated in the closing direction (closing operation), causing the gripping unit 80 to grip the utility pole. Note that while the gripping unit 81 is gripping the utility pole in this manner, the gripping unit load detector 125 constantly detects the load acting on the gripping unit 81, and this detection signal is input to the controller 100. Next, the boom 13 and gripping device 50 are operated appropriately to lift the utility pole gripped by the gripping unit 81 and move it above the pole erection hole (the pole erection hole excavated in the excavation work described above). Above this pole hole, the worker operates the operating device 31 and visually moves the utility pole closer to a vertical position, as shown in Figure 15(A). When the operator reaches the target position, the operator turns on automatic vertical switch 34. When automatic vertical control unit 105 of controller 100 receives an operation signal from automatic vertical switch 123 and determines that the tilt angle of gripper unit 81 is within a predetermined angle, it outputs a command signal to operation control unit 102. When operation control unit 102 receives the command signal from automatic vertical control unit 105, it operates, based on the detection information from gripper tilt angle detector 124, to extend and retract vertical swing cylinder 62 to correct the tilt of gripper unit 81 in the front-to-rear direction, and rotates gripper motor 79 to correct the tilt of gripper unit 81 in the left-to-right direction, thereby bringing gripper unit 81 to a horizontal position. As a result, the utility pole gripped by gripper unit 81 can be brought to a vertical position, as shown in FIG. 15(B). Furthermore, if the position (front, back, left, or right) of the utility pole in a vertical position is misaligned with the position of the pole hole, the boom 13 can be extended and rotated to move the utility pole horizontally (front, back, left, or right) while maintaining the vertical position, and the utility pole can be positioned directly above the pole hole.

[0060] Next, to move the vertically oriented utility pole vertically downward toward the pole hole, the mode selection switch 33 is operated to switch from normal mode to vertical gripper operation mode. As shown in FIG. 16(A), when the gripper 81 grips a vertically oriented utility pole, a load corresponding to the weight of the pole acts downward on the gripper 81. After switching the mode selection switch 33 to the vertical gripper operation mode, the boom 13 is raised and lowered in response to operation of the boom rotation / hoisting control lever 32a, and the gripper 81 is moved vertically downward to insert the utility pole held by the gripper 81 into the pole hole. As the gripper 81 is moved vertically downward, the lower end of the utility pole held by the gripper 81 abuts against the bottom of the pole hole, and the gripper 81 receives a ground reaction force (a force pushing up the utility pole) from the bottom of the hole via the utility pole. As a result, as shown in FIG. 16(B), the load acting on the gripping portion 81 is reversed from downward to upward. At this time, the load determination portion 106 of the controller 100 outputs a restriction signal to the operation control portion 102 when the load acting on the gripping portion 81 becomes zero, causing the gripping portion 102 to stop moving vertically downward. As a result, the vertical downward movement of the gripping portion 81 (utility pole) is stopped the instant the lower end of the utility pole abuts against the bottom of the pole hole, and the utility pole is positioned relative to the pole hole. After inserting the utility pole to the bottom of the pole hole in this way, the lower end of the utility pole can be buried and compacted in the pole hole by filling the gap between the utility pole and the pole hole with earth and sand or the like and compacting it (by backfilling with excavated soil, broken stone, etc.). This completes the pole installation work of installing the utility pole in the pole hole.

[0061] [3. Pillar removal work] Next, there will be explained the pole extraction work (automatic pole extraction work) by the grip-type hole digging pole erection vehicle 1. Figures 17 to 19 are schematic diagrams showing the flow of the automatic pole extraction work.

[0062] First, to perform automatic pole removal work, as shown in Figure 17(A), as preparation for the work, a pole removal machine 40 is installed near the base of the existing utility pole to be removed (indicated by the symbol "P" in Figures 17 to 19). The chain 45 of this pole removal machine 40 is wound around the utility pole several times, and both ends of the chain 45 are engaged with the upper ends of the pole removal machine cylinder 41. In addition, hydraulic hoses 46 and 47 (see Figure 10) of the pole removal machine cylinder 41 are connected to the hydraulic outlet of the vehicle, and the pole removal machine cylinder 42 is connected to the electromagnetic proportional control valve V10. In addition, the operating device 31 is operated to move the gripping part 81 to the vicinity of the center of gravity of the utility pole, and then the gripping part 81 is operated in the closing direction to grip the center of gravity of the utility pole. This completes the preparation for the work.

[0063] After completing the advance preparations for the work, the worker turns on the automatic pole removal switch 35 of the operating device 31. This causes the automatic pole removal control unit 107 of the controller 100 to start the automatic pole removal work in accordance with a pre-stored automatic pole removal program. First, when the automatic pole removal control unit 107 receives an operation signal from the automatic pole removal switch 35, it outputs a command signal to the operation control unit 102, which extends the gripper cylinder 99 and operates the gripping unit 81 (gripping claws 82) in the opening direction. This temporarily loosens the grip of the utility pole by the gripping unit 81, as shown in FIG. 17(B). This operation of the gripping unit 81 in the opening direction (release operation) is performed by operating the pair of gripping claws 82 in directions that move them apart from each other, to the extent that the utility pole does not come off the gripping unit 81, thereby weakening the gripping force of the gripping unit 81 on the utility pole (at this time, a small gap may be formed between the gripping claws 82 and the utility pole). The opening operation of the gripper 81 (extension of the gripper cylinder 99) is detected by the pressure detector 126 (the pressure detector 126 of the gripper cylinder 99). rod This is continued until the pressure in the oil chamber (side oil chamber pressure) becomes equal to or lower than the second threshold pressure.

[0064] Next, the automatic pole extraction control unit 107 outputs a command signal to the operation control unit 102 to extend the pole extraction machine cylinder 41, as shown in Figure 17(C). By extending this pole extraction machine cylinder 41, the chain 45 of the pole extraction machine 40 becomes tensed (a state in which it tightens the utility pole), and the utility pole is pulled out of the ground in accordance with the extension of this pole extraction machine cylinder 41.

[0065] Next, the automatic column extracting control unit 107 judges whether the column extracting machine cylinder 41 has reached a fully extended state (stroke end in the extension direction). Based on the detection information from the column extracting machine cylinder pressure detector 127, the automatic column extracting control unit 107 judges that the column extracting machine cylinder 41 has reached the stroke end in the extension direction (fully extended state) when the pressure in the bottom-side oil chamber of the column extracting machine cylinder 41 exceeds a predetermined pressure (maximum pressure). When the automatic column extracting control unit 107 judges that the column extracting machine cylinder 41 has reached the fully extended state (stroke end in the extension direction), it outputs a command signal to the operation control unit 102 to stop the extension operation of the column extracting machine cylinder 41 and hold the column extracting machine cylinder 41 in the fully extended state for a predetermined time (for example, 1 second), as shown in Fig. 18(D).

[0066] Subsequently, the automatic pole removal control unit 107 outputs a command signal to the operation control unit 102 to contract the gripper cylinder 99 and operate the gripping unit 81 (gripping claws 82) in the closing direction. As a result, the pole is gripped by the gripping unit 81, as shown in FIG. 18(E). This operation of the gripping unit 82 in the closing direction (the contraction operation of the gripper cylinder 99) is detected by the pressure detector 126 (the pressure of the gripper cylinder 99). rod This is continued until the pressure in the side oil chamber becomes equal to or greater than the first threshold pressure (until the gripping force of the gripping portion 81 reaches a specified gripping force).

[0067] Next, the automatic pole extraction control unit 107 outputs a command signal to the operation control unit 102 to cause the pole extraction machine cylinder 41 to retract, as shown in Figure 18(F). By causing the pole extraction machine cylinder 41 to retract, the tension on the chain 45 is gradually released, and the pole extraction machine cylinder 41 can be retracted while the pole is held by the gripping unit 81 (a state in which the pole is held so as not to fall).

[0068] Next, the automatic pole extraction control unit 107 determines whether the pole extractor cylinder 41 has reached a fully retracted state (stroke end in the retraction direction). Based on detection information from the pole extractor cylinder pressure detector 128, the automatic pole extraction control unit 107 determines that the pole extractor cylinder 41 has reached a fully retracted state (stroke end in the retraction direction) when the pressure in the rod-side oil chamber of the pole extractor cylinder 41 exceeds a predetermined pressure (maximum pressure). When the automatic pole extraction control unit 107 determines that the pole extractor cylinder 41 has reached a fully retracted state (stroke end in the retraction direction), it outputs a command signal to the operation control unit 102, which stops the retraction operation of the pole extractor cylinder 41 and keeps the pole extractor cylinder 41 in the fully retracted state, as shown in Figure 19 (G). Then, when the operator confirms that the base of the utility pole is loose, he turns off the automatic pole extraction switch 35 of the operating device 31, and the operations up to that point constitute one cycle, thereby completing the automatic pole extraction operation.

[0069] When the automatic pole removal work is completed, remove the pole removal machine 40 from the utility pole as shown in Figure 19(H). 19(I), the worker operates the operating device 31 to appropriately operate the boom 13 and the gripping device 50, and moves the gripping part 81 upward, thereby lifting the utility pole gripped by the gripping part 81 out of the pole hole and moving it to a predetermined location. Then, after the utility pole has been lowered to the predetermined location, the worker operates the gripping claws 82 in the opening direction, releasing the grip of the utility pole by the gripping part 81, thereby allowing the utility pole to be placed in the predetermined location.

[0070] Although not shown, if the automatic pole removal switch 35 is not switched from on to off within a predetermined time (e.g., 10 seconds) after the first cycle of the automatic pole removal operation is completed, the second cycle of the automatic pole removal operation is initiated (if the automatic pole removal switch 35 is not switched from on to off, the operation can continue to the third cycle and beyond). In other words, if the pole cannot be removed in one cycle of the automatic pole removal operation (if the base of the pole does not loosen), the second and subsequent cycles of the automatic pole removal operation will be automatically initiated if the automatic pole removal switch 35 is left on (the automatic pole removal operation will be automatically repeated). In addition, in the second and subsequent cycles of the automatic pole removal operation, in order to prevent the pole to be removed from falling from the gripper 81, the gripper 81 is held in a closed state until the detected pressure of the pole removal machine cylinder pressure detector 127 (the pressure in the bottom-side oil chamber of the pole removal machine cylinder 41) reaches a predetermined value. When the detected pressure reaches the predetermined value, the gripper 81 is operated in the opening direction. In other words, in the first cycle of the automatic pole removal work described above, the pole removal machine cylinder 41 was started to extend after the gripping portion 81 was operated in the opening direction (after the gripping by the gripping portion 81 was loosened), but in this second cycle, the pole removal machine cylinder 41 was started to extend first, and after the detected pressure of the pole removal machine cylinder pressure detector 127 reached a predetermined value, the gripping portion 81 was operated in the opening direction (loosening the gripping), thereby preventing the utility pole from falling during the pole removal process.

[0071] The main effects achieved in this embodiment can be summarized as follows:

[0072] First, according to this embodiment, if the auger screw 25 tilts forward, backward, left, or right beyond the allowable angle relative to the vertical direction, the operation of the boom 13 and the auger screw 25 can be regulated to automatically stop the excavation work of the auger screw 25, thereby making it possible to prevent the formation of a pole hole for erecting a utility pole at an angle relative to the vertical.

[0073] Furthermore, according to this embodiment, when the gripping portion 81 is moved downward to insert the utility pole gripped by the gripping portion 81 into a pole hole (a pole hole for erecting a pillar-shaped object), if the load acting on the gripping portion 81 drops below a threshold load, it is determined that the lower end of the utility pole has come into contact with the bottom of the pole hole, and the downward movement of the gripping portion 81 (utility pole) is automatically stopped. This prevents the worker from continuing to move the gripping portion 81 downward without realizing that the lower end of the utility pole has come into contact with the bottom of the hole (which would cause the lower end of the utility pole to be pressed excessively against the bottom of the hole), and makes it possible to prevent a situation in which excessive load is applied to the gripping portion 81 or the utility pole, causing damage.

[0074] Furthermore, according to this embodiment, when the automatic vertical switch 34 is operated, the attitude of the gripping unit 81 is changed by activating the vertical swivel cylinder 62 and the gripper motor 79 in accordance with the inclination angle of the gripping unit 81 relative to the horizontal plane detected by the gripping unit inclination angle detector 124, and the utility pole gripped by this gripping unit 81 can be brought into a vertical attitude along the vertical direction.Therefore, even on sloping ground such as mountainous areas, the utility pole gripped by the gripping unit 81 can be automatically brought into a vertical attitude without the need for skilled operating skills, and the work efficiency of pole erection work can be dramatically improved.

[0075] In this embodiment, only when the tilt angle of the gripping portion 81 relative to the horizontal plane detected by the gripping portion tilt angle detector 124 is within a predetermined angle, the electric pole gripped by the gripping portion 81 is Since the control is performed to change the gripping part 81 into a vertical position, the range of movement required to change the gripping part 81 into a vertical position can be limited, preventing the utility pole from interfering with surrounding structures or the ground or coming into contact with the worker, thereby ensuring the safety of the work.

[0076] Furthermore, according to this embodiment, there is no need to use large heavy machinery such as a crane to lift the utility pole to be removed. The gripping device 50 of this gripping-type hole-digging and pole-setting vehicle 1 can be used to appropriately switch between gripping and releasing (relaxing the grip) the utility pole to be removed, and pole removal work can be performed using the pole extraction machine 40.Therefore, different types of work (pole installation work and pole removal work) can be performed with a single gripping-type hole-digging and pole-setting vehicle 1, which expands the uses of the gripping device 50 and further increases the added value of this gripping-type hole-digging and pole-setting vehicle 1.

[0077] Furthermore, in this embodiment, a series of pole extraction operations can be performed automatically and continuously by a linked operation that combines the opening and closing operation of the gripping portion 31 with the extension and contraction operation of the pole extraction machine 40, thereby reducing the effort and burden on the worker and improving the efficiency and safety of the pole extraction operation.

[0078] Furthermore, in this embodiment, even if the pole cannot be extracted by a single extension / retraction operation of the pole extraction machine 40, the pole extraction machine 40 can automatically and continuously perform multiple extension / retraction operations in response to the operation of the automatic pole extraction switch 35, thereby further improving the work efficiency of the pole extraction work.

[0079] The present invention is not limited to the above-described embodiment, and can be modified as appropriate without departing from the spirit of the present invention.

[0080] In the above embodiment, the gripping portion load detector 125 is configured as a pin-type load cell that detects the load acting on the connecting pin 63, but this configuration is not limited to this. For example, the gripping portion load detector 125 may be configured as a pressure detector that detects the pressure of the hydraulic oil supplied to the bottom-side oil chamber and / or rod-side oil chamber of the vertical swing cylinder 62.

[0081] In the above embodiment, the gripping force of the gripping portion 81 (the force with which the gripping claws 82 grip the object) is controlled by the gripper cylinder 99. rodAlthough the pressure is detected indirectly based on the pressure in the side oil chamber, this is not limited to this configuration. For example, a load cell or strain gauge may be provided inside the gripping claw 82 to directly detect the gripping force of the gripping portion 81.

[0082] In the above embodiment, the stroke end in the extension / retraction direction of the column puller cylinder 41 is detected by the pressure in the bottom side oil chamber and the rod side oil chamber of the column puller cylinder 41, but this configuration is not limited to this and, for example, it may be configured by a stroke detector that detects the position (stroke position) in the extension / retraction direction of the piston rod 43 of the column puller cylinder 41.

[0083] In the above embodiment, the operating device 31 is provided on the operating seat 30 on the vehicle body 2, but this configuration is not limited to this, and for example, the operating device 31 may be configured as a wired or wireless remote control operating device (portable operating device).

[0084] In addition, in the above embodiment, a PTO-driven hole-digging pole-setting vehicle was exemplified, in which engine power is extracted by a PTO mechanism (power take-off mechanism) to drive a hydraulic pump, but this configuration is not limited to this, and the hole-digging pole-setting vehicle may be an electrically driven (battery-driven) hole-digging pole-setting vehicle, or a hybrid hole-digging pole-setting vehicle that has both an electrically driven and a battery-driven type and can selectively switch between power sources. [Explanation of symbols]

[0085] 1 Grasping type hole digging pole erecting vehicle 2. Body 12 Swivel table 13. Boom 20 Auger device 22 Auger motor 25 Earth Ogre 31 Operating device 33 Mode selection switch 34 Automatic vertical switch 35 Automatic column removal switch 40 Post removal machine 41 Pillar removal machine cylinder 50 Gripping device 51 Arm 55 Arm cylinder 60 First joint member 62 Vertical Swing Cylinder 70 Second joint member 71 Horizontally Swinging Cylinder 79 Gripper motor 80 Gripper 81 Gripping part 82 Gripping claw 99 Gripper cylinder 100 Controllers 101 Position calculation section 102 Operation control section 103 Auger inclination determination unit 104 Grip determination section 105 Automatic vertical control section 106 Load judgment section 107 Automatic column removal control unit 123 Auger tilt angle detector 124 Grip tilt angle detector 125 Grip load detector 126 Gripper cylinder pressure detector 127 Pillar removal machine cylinder pressure detector 128 Pillar removal machine cylinder pressure detector

Claims

1. a boom provided on the vehicle body so as to be capable of raising and lowering and extending; a gripping portion having a pair of gripping claws that can be opened and closed to grip a columnar object; a support mechanism provided between the tip of the boom and the gripping part, which changes the attitude of the gripping part with respect to the tip of the boom; a pole extraction machine that extracts a pole-like object installed on the ground in response to the extension and contraction of a pole extraction cylinder; an operating device for operating the boom, the gripping unit, the support mechanism, and the pole extracting machine; an operation control unit that controls the operation of the boom, the gripping unit, the support mechanism, and the pole extraction machine in response to operation of the operation device, The control device for a gripping-type pole-digging and pole-erecting vehicle is characterized in that the operation control unit is configured to extend the pole-erecting cylinder while the gripping part's grip on the pole-erecting object is relaxed, thereby allowing the pole-erecting machine to pull out a pole-erecting object installed in the ground.

2. The control device for a gripping-type pole-digging vehicle as described in claim 1, characterized in that the operation control unit is configured to successively perform the following operations: a first operation in which a pole-like object installed on the ground is gripped by the gripping unit, and the gripping unit loosens the grip to a degree that prevents the pole from falling off, and the pole-removal cylinder is extended to pull the pole out of the ground; a second operation in which the pole is gripped by the gripping unit again to hold the pole; and a third operation in which the pole-removal cylinder is retracted while the pole is gripped by the gripping unit.

3. the operating device has a continuous operation operating device for continuously performing the first operation to the third operation, The operation control unit is configured to be able to continuously perform the continuous operations from the first operation to the third operation multiple times in response to the operation of the continuous operation operation device, a pressure detector for detecting the pressure in the extension-side oil chamber of the column-pulling cylinder; The control device of the gripping-type pole-digging and erecting vehicle described in claim 2, characterized in that when the continuous operation is performed multiple times, the operation control unit starts the extension operation of the pole-removal cylinder during the first operation from the second time onwards among the multiple times, and releases the grip of the gripping unit when the pressure in the extension side oil chamber detected by the pressure detector reaches a predetermined value.

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