JP4600148B2 - Self-propelled work machine - Google Patents

Description

  The present invention relates to a self-propelled working machine such as a hydraulic excavator that can move up and down an inclined path such as a staircase or a steep slope.

  In recent years, various techniques for enabling a self-propelled working machine to move up and down stairs and steep slopes have been developed for the purpose of demolition work in buildings.

For example, in Patent Document 1, in a crawler-type traveling vehicle, the upper working body can be rotated around a support shaft on the front end side with respect to the lower traveling body (that is, the rear end of the upper working body can be raised and lowered). In this manner, the upper working body can take a normal posture and a forward tilting posture that are substantially parallel to the lower traveling body by rotating the upper working body. According to this work machine, the upper work body is substantially moved regardless of the inclination of the slope by running the slope while the upper work body is tilted forward to an angle substantially equal to the slope angle of the slope. It is possible to raise and lower the ramp with a stable posture maintained in a horizontal state.
JP-A-11-334656

  The traveling when raising and lowering the ramp is in an unstable state as compared with the normal traveling. Therefore, in order to realize the safe raising and lowering, it is desired to suppress the traveling speed of the working machine. . Such suppression of the traveling speed is generally performed by performing a so-called half lever operation that suppresses the operation amount of the traveling operation lever for driving to a value lower than the upper limit. The burden of is also great. Further, if the lever operation amount is accidentally set to a full operation or an amount close thereto, the actual traveling speed may exceed the preferred speed for safely raising and lowering.

  In view of such circumstances, an object of the present invention is to provide a self-propelled working machine that is excellent in safety of ascending / descending ramps and has a low burden on an operator.

As means for solving the above-mentioned problems, a self-propelled working machine according to the present invention has, as its basic configuration, a traveling body capable of traveling on an inclined road, a driving operation member for driving, and an operation of the driving operation member. A travel driving means that travels the traveling body at a speed corresponding to the amount, a restriction state that restricts a maximum traveling speed by the travel driving means when the travel operation member is fully operated, and a restriction state that cancels the restriction. Speed limiting means switchable to an unrestricted state.

  In this configuration, by switching the speed limiting means to the non-restricted state, it is possible to perform normal traveling without receiving a traveling speed, while the speed limiting means is set to the speed when ascending / descending a ramp such as stairs. By switching to the restricted state, it is possible to ascend and descend a safe ramp without placing a heavy burden on the operator. That is, when the speed limiting means is in the limited state, even if the travel operation member is fully operated, the maximum travel speed corresponding to the travel operation member is limited as compared with the normal travel, so that the speed is low while performing the full operation. It is possible to move up and down the ramp safely.

  It should be noted that the speed limit during the full operation only needs to be lower than the maximum travel speed during normal travel, and can be set as appropriate within that range. For example, it is not always necessary to determine the speed limit on the premise that the travel operation member is fully operated when the ramp is moved up and down. That is, the speed limit may be set on the premise that the travel operation member is operated with an operation amount smaller than the full operation even when the speed limiting means is in the limited state. Even in such a case, even if the operator makes a full operation by mistake, the maximum traveling speed at that time can be suppressed as compared with that during normal traveling, so that higher safety can be obtained as compared with a conventional self-propelled working machine.

Furthermore, the self-propelled working machine according to the present invention, the traveling drive means comprises a fluid pressure source, the running body at a speed corresponding to the supply flow rate supplied with working fluid from the fluid pressure supply source A fluid pressure actuator for actuating the fluid, and a flow rate of the working fluid supplied to the fluid pressure actuator from the fluid pressure supply source is adjusted between the fluid pressure supply source and the fluid pressure actuator. A flow rate control valve that adjusts the flow rate according to the amount, and the speed limiting means is provided separately from the flow rate control valve, and a part of the working fluid supplied from the fluid pressure supply source to the fluid pressure actuator Includes a switching valve that can be switched between a first position that allows the flow to be diverted to the escape flow path and a second position that restricts the diversion flow rate of the working fluid to the escape flow path from the first position .

  According to this configuration, the flow rate of the working fluid supplied from the fluid pressure supply source to the actuator can be reduced by simply switching the switching valve provided in the relief flow path between the first position and the second position. It is possible to switch between a restricted state (first position) and an unrestricted state (second position).

  Further, the switching between the limited state and the non-restricted state of the speed limiting unit may be performed manually, for example, and includes a limiting control unit that switches the speed limiting unit to the limiting state at least when the ramp is moved up and down. By doing so, higher safety can be obtained.

  As a means for determining whether or not the ramp is being raised or lowered, for example, an inclinometer may be provided in the lower traveling body and the speed may be limited when the detected inclination angle is equal to or greater than a certain value. The upper working body mounted on the lower traveling body is relatively movable with respect to the traveling body between a normal position and an inclined position inclined from the normal position to the upside of the slope. In a self-propelled working machine that is supported and is configured to switch the upper working body from the normal position to the inclined position when moving up and down the ramp, the speed limiting means is provided when the upper working body is not in the normal position. By switching to the limit state, it is possible to automatically execute an appropriate speed limit without adding an expensive inclinometer.

As described above, according to the present invention, the speed limiter is limited when the ramp is moved up and down, that is, the maximum travel speed by the travel drive unit when the travel operation member is fully operated is limited as compared with the normal travel. By switching to the state, there is an effect that the ramp can be safely moved up and down without imposing a heavy burden on the operator. Further, the flow rate of the working fluid supplied from the fluid pressure supply source to the actuator is limited with a simple configuration in which the switching valve provided in the escape passage is simply switched between the first position and the second position ( It is possible to switch between a first position) and an unrestricted state (second position).

  A preferred embodiment of the present invention will be described with reference to the drawings. Note that the self-propelled working machine 10 shown in this embodiment is one equipped with a scraper (scraping plate member) 12 as a work attachment, but the present invention is not limited to this, and a hydraulic excavator or crusher It can be applied to various self-propelled working machines such as machines.

  A self-propelled working machine 10 shown in FIGS. 1 to 7 includes a lower traveling body 14 and an upper working body 16.

  The lower traveling body 14 includes a vehicle body frame 18 shown in FIGS. 4 and 5 and traveling crawlers 20L and 20R provided on the left and right sides thereof. These crawlers 20L and 20R have iron rings (not shown) arranged in the front and rear, and crawler belts stretched between these iron rings, and have a substantially oval shape extending in the front-rear direction when viewed from the side. .

  A front end of a undulation frame 24 is rotatably connected to the body frame 18 around a horizontal support shaft 22 provided at a front end in the traveling direction, and the upper portion shown in FIGS. A work body 16 is mounted.

  As shown in FIGS. 4 and 5, an upper working body operating cylinder 26 made of a hydraulic cylinder is provided between the hoisting frame 24 and the vehicle body frame 18. One end of the upper work body operating cylinder 26 is pivotally supported on the front end of the body frame 18 via a pin 25 in the left-right direction, and the other end is substantially in the front-rear direction of the hoisting frame 24. The upper and lower frames 24 are undulated by the expansion and contraction of the upper work body operation cylinder 26 and are mounted on the undulation frame 24. The work body 16 is switched between a normal position as shown in FIG. 3 and an inclined position as shown in FIGS. 1 and 2.

  Here, the normal position is a position where the upper working body 16 is supported in a substantially horizontal posture with respect to the lower traveling body 14, and normal traveling is possible at this position. On the other hand, the inclined position is a position where the upper working body 16 is inclined forward and downward by a predetermined angle θ with respect to the lower traveling body 14, and the predetermined angle θ is an elevation of the self-propelled working machine 10. Is set to an angle (about 45 ° in the example) substantially equal to the inclination angle of the ramp (step 28 in the example).

  1 to 3, FIG. 1 shows a state where the self-propelled working machine 10 is moving up and down on the stairs 28, and FIG. 2 shows the self-propelled working machine 10 as described in detail later. FIG. 3 shows a state immediately before riding on the upper target site (the landing 29 in the example of the figure) following the upper end of the staircase 28, and FIG. 3 shows a state after the self-propelled working machine 10 has completely climbed on the landing 29. Show.

  The “upper destination” according to the present invention is not limited to the landing 29 but may be a wide flat surface that continues to the upper end of a steep slope, for example.

  The undulating frame 24 has a slewing bearing portion 30 as shown in FIGS. 4 and 5 at a substantially middle portion in the front-rear direction, and the upper work shown in FIGS. 1 to 3 on the slewing bearing portion 30. The body 16 is supported so as to be able to turn around a vertical axis.

  The upper working body 16 includes a turning body 34 on which a driver's seat 32 is mounted, and a boom support member 36 is provided at the front end of the turning body 34 so as to be rotatable (swing) around a vertical axis 35. It has been. A boom 38 is attached to the boom support member 36 so as to be rotatable (can be raised and lowered) about a left-right axis 37, and can be rotated about a left-right axis 39 at the tip of the boom 38. An arm 40 is attached so that the scraper 12 is provided at the tip of the arm 40 so as to be rotatable about a left-right axis.

  The boom 38 is raised and lowered, the arm 40 is rotated with respect to the boom 38, and the scraper 12 is rotated with respect to the arm 40. The boom cylinder 42, the arm cylinder 44, and the attachment cylinder 46 are hydraulic cylinders, respectively. Realized by expansion and contraction.

  A front projecting member 50 and a rear projecting member 52 as shown in FIGS. 4 to 6 are attached to the front and rear portions of the vehicle body frame 18, respectively. These overhang members 50 and 52 can be switched between a storage position indicated by a solid line in FIG. 4 and an overhang position indicated by a two-dot chain line in FIG.

  Among these, the front overhang member 50 assists the self-propelled working machine 10 to silently run from the stairway 28 to the landing 29 by the overhang, and the rear overhang member 52 is lowered by the overhang. This is to realize that the traveling body 14 makes a small turn around the front end of the left crawler 20L or the front end of the right crawler 20R. These overhang members 50 and 52 are not particularly essential elements in the present invention.

  The front projecting member 50 includes a rotating arm 53 and a pair of left and right casters 54 that are rolling elements attached to the end of the rotating arm 53.

  The pivot arm 53 includes a pair of left and right pivot side plates 56 and a caster support plate 58. Both the rotating side plates 56 are rotatably attached to the front half portion of the vehicle body frame 18, and the caster support plate 58 is provided so as to connect these rotating side plates 56 to each other. Specifically, the pivot base end portions of both the pivot side plates 56 are pivoted on the pivot shaft 60 so as to be pivotable about a pivot shaft 60 provided in the front half of the body frame 18 in the left-right direction. The pivot tip portions are supported by the caster support plate 58 extending in the left-right direction.

  Each of the casters 54 is attached to the lower side of the caster support plate 58 via a caster bracket 62. These caster brackets 62 are attached to the caster support plate 58 so as to be rotatable about an unillustrated axis extending in the thickness direction of the caster support plate 58, and the caster 54 is attached to the caster support plate 58. It is rotatably held via an axis 64 in a direction parallel to the axis.

  A front projecting member operating cylinder 66 made of a hydraulic cylinder is interposed between the rotating side plate 56 and the vehicle body frame 18, and the front projecting member 50 is brought into the retracted position by expansion and contraction of the front projecting member operating cylinder 66. Rotation operation is performed between the overhang positions.

  Specifically, a cylinder bracket 68 that protrudes downward from the lower surface of the vehicle body frame 18 is provided at a portion of the vehicle body frame 18 that is behind the intermediate position in the front-rear direction, and the cylinder bracket 68 is provided with a front extension member operation cylinder 66. The head-side end portion is connected to the left and right pins 70 so as to be relatively rotatable, and the rod-side end portion of the front projecting member operating cylinder 66 is turned to the both directions via the left and right pins 72. The side plate 56 is connected to the vicinity of the rotation base end portion so as to be relatively rotatable.

  Then, in a state where the front projecting member operating cylinder 66 is extended, the entire front projecting member 50 is stored in a storage position that fits inside the outer shape of the crawlers 20L and 20R as seen from the side as shown by a solid line in FIG. When the front projecting member operating cylinder 66 contracts, the front projecting member 50 is projected to a projecting position that largely protrudes from the lower surfaces of the crawlers 20L and 20R, as indicated by a two-dot chain line in FIG. . As shown in FIG. 2, the amount of overhang is such that the caster 54 of the front overhang member 50 in the overhang position lands on the landing 29 just before the self-propelled working machine 10 reaches the landing 29. The overhang amount is set at or near the overhang amount.

  On the other hand, the rear projecting member 52 includes a rotating arm 73 and a pair of left and right casters 74 which are rolling elements attached to the end of the rotating arm 73, as with the front projecting member 50.

  The pivot arm 73 includes a pair of left and right pivot side plates 76 and a caster support plate 78. Both the rotation side plates 76 are rotatably attached to the rear end portion of the vehicle body frame 18, and the caster support plate 78 is provided so as to connect the rotation side plates 76 to each other. Specifically, a bracket 79 projects rearward from the rear end of the vehicle body frame 18, and the rotation base end portions of the both rotation side plates 76 can rotate about the support shaft 80 in the left-right direction. The pivot tips of the pivot side plates 76 are connected to each other by the caster support plate 78 extending in the left-right direction.

  Each caster 74 is attached to the lower side of the caster support plate 78 through a caster bracket 82 in the same manner as the caster 54. That is, the left and right caster brackets 82 are attached to the caster support plate 78 so as to be rotatable about an unillustrated axis extending in the thickness direction of the caster support plate 78, and the caster 74 is supported by the caster. It is rotatably held via an axis 84 in a direction parallel to the plate 78.

  A rear projecting member operating cylinder 86 made of a hydraulic cylinder is also interposed between the rotating side plate 76 and the vehicle body frame 18, and the rear projecting member 52 is moved by the expansion and contraction of the rear projecting member operating cylinder 86. A rotation operation is performed between the storage position and the overhang position.

  Specifically, the head side end portion of the rear extension member operating cylinder 86 is relative to the cylinder bracket 68 via a left and right pin 90 positioned slightly rearward of the pin 70 in the cylinder bracket 68. The rod-side end of the rear-side extending member operating cylinder 86 can be relatively rotated to a portion in the vicinity of the rotation base end portions of the both rotation-side plates 76 via a pin 92 in the left-right direction. It is connected to. Then, in a state where the rear side extension member operating cylinder 86 is extended, the rear side extension member 52 as a whole is stored in a retracted position that fits inside the outer shape of the crawlers 20L and 20R as seen from the side as shown by the solid line in FIG. On the other hand, when the rear side extension member operating cylinder 86 contracts, the rear side extension member 52 is extended to the extension position protruding downward from the lower surfaces of the crawlers 20L and 20R, as shown by the two-dot chain line in FIG. It is like that.

  The overhang amount of the rear side overhanging member 52 is set to an amount that is smaller than the overhanging amount of the front side overhanging member 50 and that allows the undercarriage 14 to turn in a small direction as the caster 54 rolls. Has been. That is, in the state in which the rear side extension member 52 is in the extension position, for example, by operating the left crawler 20L in the forward direction while the right crawler 20R is stopped, the front end position of the right crawler 20R is turned to the right. The lower traveling body 14 turns slightly clockwise as a center, and conversely, the left crawler 20L is operated in the forward direction while the left crawler 20L is stopped, so that the front end position of the left crawler 20L is set as the left turning center. The lower traveling body 14 is turned slightly to the left.

  FIG. 7 shows an example in which the entire self-propelled work machine 10 is turned 180 ° at the landing 29 using the small turn, and in this example, only the left crawler 20L is operated by the left crawler 20L. By repeating the small turn with the front end portion as the turning center O, the turning within the narrow landing 29 is possible.

  Next, referring to FIGS. 8 to 10, fluid pressure circuits (hydraulic circuits in the illustrated example) mounted on the self-propelled work machine 10 to operate the hydraulic cylinders and the travel motors and swing motors (not shown) will be described. While explaining.

  The hydraulic circuit includes main pumps 101 and 102 including a hydraulic pump and a pilot pump 104 as a hydraulic pressure supply source. These pumps 101, 102, 104 are connected to the output shaft of the engine 100, and discharge hydraulic fluid when driven.

  Both the main pumps 101 and 102 supply hydraulic oil to each hydraulic actuator mounted on the self-propelled work machine 10. Specifically, in addition to the upper work body operation cylinder 26, the boom cylinder 42, the arm cylinder 44, the attachment cylinder 46, and the both overhang member operation cylinders 66 and 86, the span cylinder that expands and contracts the spans of the left and right crawlers 20L and 20R. 106, although not shown, a left and right traveling motor for operating the left and right crawlers 20L and 20R, a turning motor for turning the upper working body 16, a swing cylinder for turning the boom support member 36 to the left and right, etc. Supply hydraulic oil to

  A control valve block 110 is interposed between the main pumps 101 and 102 and the hydraulic actuators. The control valve block 110 includes a center bypass passage 111 that guides hydraulic oil supplied from the main pump 101 through the supply oil passage 121 to the tank 108, and hydraulic oil supplied from the main pump 102 through the supply oil passage 122. A center bypass passage 112 leading to the tank 108 and a plurality of control valves are arranged in series along the center bypass passages 111 and 112.

  Specifically, on the side of the center bypass passage 111, an arm control valve 113 connected to the arm cylinder 44, a swing control valve 114 connected to the swing motor, and a left travel connected to the left travel motor. The control valve 115 is arranged, and on the center bypass passage 112 side, an attachment control valve 116 connected to the attachment cylinder 46, a boom control valve 117 connected to the boom cylinder 42, and the swing cylinder The swing control valve 118 to be connected, the right travel control valve 119 connected to the right travel motor, the span cylinder 106, the upper work body operation cylinder 26, and the front and rear extension member operation cylinders 66 and 86 are provided in common. A common control valve 120 is arranged.

  These control valves 113 to 120 are each constituted by a three-position direction switching valve having a flow rate adjusting function (the swing control valve 117 is a manual switching valve, and the other control valves are hydraulic pilot switching valves). In the middle position in the figure, the hydraulic oil supplied from the main pump 101 or the main pump 102 is bypassed to the tank 108 side as it is, while the pilot operation or the manual operation by the pilot pressure of the pilot pump 104 is performed from the neutral position. The hydraulic fluid is guided to the connected hydraulic actuator at a flow rate corresponding to the operation amount.

  A travel remote control valve 124 is interposed between the pilot pump 104 and the travel control valves 115 and 118. The travel remote control valve 124 has left and right travel levers (travel operation members) 125L and 125R as shown in FIGS. 11A and 11B, and the travel control valve corresponding to the travel lever is operated in the operation direction. A pilot pressure having a magnitude corresponding to the operation amount is introduced to the corresponding pilot section. Therefore, by operating the travel levers 125L and 12R of the travel remote control valve 124, the left and right crawlers 20L and 20R can be traveled at a speed corresponding to the operation amount.

  Further, as a feature of this apparatus, relief oil passages 126A and 126B branch from the supply oil passages 121 and 122 to the tank 108 side, respectively, and flow relief valves 127A and 127B and switching are provided in the relief oil passages 126A and 126B, respectively. Valves 128A and 128B are arranged in series, respectively.

  Both the switching valves 128A and 128B have a shut-off position (the “second position” in FIG. 2; the left position in the figure) that shuts off the relief oil passages 126A and 126B, respectively, and a relief position that communicates the oil passages 126A and 126B. ("First position" in claim 2; right position in the figure), and the switching operation is performed in conjunction with the shut-off position and the escape position. Therefore, when both the switching valves 128A and 128B are switched to the shut-off position, the total amount of oil discharged from the main pumps 101 and 102 is sent to the control valve block 110, so that the normal amount corresponding to the operation amount of the travel lever is reached. While the hydraulic oil supply flow rate and the normal running speed are ensured, when the switching valves 128A and 128B are switched to the escape position, the hydraulic oil supply flow rate is reduced by the relief amount and the travel lever is fully operated. The traveling speed at the time, that is, the maximum speed is limited.

  Note that the “second position” in claim 2 does not necessarily have to be a position at which the relief oil passages 126A and 126B are completely shut off, and the operation to the relief oil passages 126A and 126B rather than the “first position”. If the oil diversion flow rate is limited, it is possible to switch between a state where the traveling speed is limited (first position) and a state where the traveling speed is not limited (second position).

  These switching valves 128A and 128B may be switched only by manual operation. For example, these switching valves 128A and 128B are electromagnetic switching valves, and their position switching is electrically controlled by a controller 156 described later. It is good also as a structure. This point will be described in detail later.

  The common control valve 120 has pilot portions 131 and 132, and electromagnetic switching valves 133 and 134 are provided between the pilot portions 131 and 132 and the pilot pump 104, respectively. The electromagnetic switching valves 133 and 134 have solenoids b1 and b2, respectively. When the solenoids b1 and b2 are not energized, the pilot oil is guided to the pilot parts 131 and 132 to generate a pilot pressure. On the other hand, when the solenoids b1 and b2 are energized, the pilot oil from the pilot pump 104 is allowed to escape to the tank 108.

  The common control valve 120 maintains a neutral position (center bypass position) when pilot pressure is not supplied to both pilot parts 131 and 132 or when equivalent pilot pressure is supplied, while pilot pressure is applied only to the pilot part 131. Is supplied to the oil passage 137 and switched to a position (lower position in the figure) where the oil passage 138 is connected to the tank 108 side. When pilot pressure is supplied only to the pilot section 132, the pump discharge oil is discharged. The oil is guided to the oil passage 138 and switched to the position (the upper position in the figure) where the oil passage 137 is connected to the tank 108 side.

  The oil passage 137 branches into two branch oil passages 141 and 142, and the oil passage 138 branches into two branch oil passages 144 and 145. On the downstream side thereof, an electromagnetic switching valve 148 for switching the span cylinder 106 or the upper work body operating cylinder 26 between an operating state and a stopped state, and the front side extending member operating cylinder 66 or the rear side extending member operating cylinder 86 are provided. An electromagnetic switching valve 147 for switching between an operating state and a stopped state, a selection valve 150 for switching the span cylinder 106 and the upper work body operating cylinder 26 alternatively to an operable state by manual operation, and manual operation Are provided with front and rear switching valves 152 and 154 for selectively switching the front and rear projecting member operating cylinders 66 and 86 to an operable state.

  Specifically, the branch oil passage 141 reaches the front / rear switching valve 152 through the electromagnetic switching valve 147, and the front / rear switching valve 152 is connected to the front side chamber of the front extension member operating cylinder 66. It is alternatively switched between the selected position (lower position in the figure) and the rear selected position (upper position in the figure) connected to the head side chamber of the rear extension member operating cylinder 86. The branch oil passage 142 reaches the selection valve 150 through an electromagnetic switching valve 148, and the selection valve 150 connects the branch oil passage 142 to the rod side chamber of the span cylinder 106 (the left position in the figure). And an upper work body operation selection position (right position in the figure) connected to the rod side chamber of each of the upper work body operation cylinders 26.

  On the other hand, the branch oil passage 144 reaches the front / rear switching valve 154 through the electromagnetic switching valve 147. The front / rear switching valve 154 connects the branch oil passage 144 to the rod side chamber of the front extension member operating cylinder 86 and the front side selection position (lower position in the figure) for connecting the rod side chamber of the front extension member operation cylinder 66. It is alternatively switched to the rear selection position (upper position in the figure). Further, the branch oil passage 145 reaches the head side chamber of each upper work body operating cylinder 26 and the head side chamber of the span cylinder 106 through the electromagnetic switching valve 148.

  The electromagnetic switching valve 147 is switched to a closed position (right position in the figure) that shuts off both of the branch oil passages 141 and 144 in an off state where the solenoid a1 is not energized, while the solenoid a1 is energized. In the ON state, the valve is switched to a valve opening position (left side position in the figure) where both the branch oil passages 141 and 144 are opened. Similarly, the electromagnetic switching valve 148 is switched to a valve closing position (right position in the figure) that shuts off both of the branch oil passages 142 and 145 when the solenoid a2 is not energized. In the energized ON state, the valve is switched to the valve opening position (left position in the figure) where both the branch oil passages 142 and 145 are opened.

  The above-described controller 156 is attached to this hydraulic circuit. The controller 156 is composed of a microcomputer or the like, and performs on / off switching of the solenoids a1, a2, b1, b2 according to an output signal (control signal) thereof.

  The travel remote control valve 124 is incorporated in an operation box 160 as shown in FIGS. 11 (a) and 11 (b), and is detachably attached to the vicinity of the driver's seat 32 together with the operation box 160. The operation box 160 is connected to the controller 156 through a wiring not shown. When the stairs 28 is raised or lowered, the traveling remote control valve 124 and the operation box 160 are removed from the upper work body 16 and the traveling remote control valve 124 and the operation box 160 are self-propelled through the hydraulic hose and the wiring not shown. The machine 10 can be remotely operated.

  The controller 156 may be provided on the operation box 160 side.

  The operation box 160 has a space 162 in the center where the travel remote control valve 124 can be stored, and a draw (upper work body undulation) / span operation switch 163, caster operation (extension) A member operation) switch 164, a tuning switch 166, and an emergency stop button 168 are provided.

  The draw / span operation switch 163 is operated from the normally held neutral position to the upper side or the lower side thereof, thereby raising or lowering the upper work body 16 (that is, raising / lowering between the inclined position and the normal position). Alternatively, an instruction to enlarge / reduce the width between the crawlers 20L and 20R is output to the controller 156.

  The caster operation switch 164 is operated from the normally held neutral position to the upper side or the lower side to raise or lower the front extension member 50 or the rear extension member 52 (that is, between the retracted position and the extension position). Rotation) command is output to the controller 156.

  The tuning switch 166 outputs a command to switch the control mode of the controller 156 between the tuning control mode and the independent control mode by the on / off operation. In the synchronization control mode, as described later, the upper work body 16 is returned from the inclined position to the normal position by contraction of the upper work body operation cylinder 26, and the front projecting member operation cylinder 66 is extended. Control for synchronizing the storage operation from the extended position to the storage position is performed, and in the independent control mode, control for individually performing the return operation and the storage operation is executed.

  The emergency stop button 168 is pressed to stop the movement of each actuator in an emergency when an accident occurs during work.

  Based on such a command operation performed in the operation box 160, the controller 156 performs on / off control of the solenoids a1 and a2 of the electromagnetic switching valves 147 and 148 and the solenoids b1 and b2 of the electromagnetic switching valves 133 and 134. The contents are as follows.

  First, for the solenoids a1 and a2, when the tuning switch 166 is on, both the solenoids a1 and a2 are turned on. When the tuning switch 166 is off, the solenoid a2 is turned on when the draw / span operation switch 163 is operated, and the solenoid a1 is turned on when the caster operation switch 164 is operated. Otherwise, solenoids a1 and a2 are kept off.

  On the other hand, for the solenoids b1 and b2, when the draw / span operation switch 163 is operated to the “down” side or the caster operation switch 164 is operated to the “up” side, the solenoid b1 is turned on, and conversely, the draw When the / span operation switch 163 is operated to the “down” side or the caster operation switch 164 is operated to the “up” side, the solenoid b2 is turned on. Otherwise, solenoids b1 and b2 are kept off.

  Further, as described above, the switching valves 128A and 128B may be electromagnetic switching valves, and the controller 156 may perform switching of the switching. In this case, the controller 156 determines whether or not the self-propelled working machine 10 is moving up and down the stairs 28, and both the switching valves 128A and 128B are forcibly opened to limit the maximum traveling speed during the moving up and down. If the controller 156 is configured to perform control such as switching to the escape position, higher safety can be ensured.

  In this case, as a method for determining whether or not the self-propelled working machine 10 is moving up and down the stairs 28, for example, an inclinometer is provided in the lower traveling body 14 and the detected inclination angle of the lower traveling body 14 is equal to or larger than a certain level. The switching valves 128A and 128B may be switched to the escape position on the assumption that the stairs 28 are being raised or lowered. However, the upper working body 16 is in the normal position as in the self-propelled working machine 10 according to this embodiment. When the upper working body 16 is not in the normal position, that is, when the upper working body operating cylinder 26 is not in the most contracted state, the stair ascending / descending is performed. By determining and switching the switching valves 128A and 128B to the relief position, it is possible to perform appropriate speed limit control without providing an expensive inclinometer. Here, the determination of the position of the upper working body 16 may be performed, for example, by detecting the stroke of the upper working body operating cylinder 26 with a stroke sensor, or a limit switch for directly detecting the position of the upper working body 16. Etc. may be provided.

  Next, an operation procedure for raising the self-propelled working machine 10 along the stairs 28 and an operation associated with the operation will be described.

A. Preparation for climbing First, before ascending the stairs 28 to the self-propelled work machine 10, the following preparation work is performed.

  1) Minimize the width (span) between the crawlers 20L and 20R. In order to perform this operation, the selection valve 150 in the hydraulic circuit shown in FIG. 8 is manually switched to the left span selection position and the tuning switch 166 of the operation box 160 is turned off, / Span operation switch 163 may be operated to the “down” side. Receiving the command signal output by this switch operation, the controller 156 switches on the solenoids a2 and b1 of the electromagnetic switching valves 148 and 133. As a result, the common control valve 120 is switched from the neutral position to the lower position in FIG. 8, and hydraulic oil discharged from the main pump 102 flows from the center bypass passage 112 to the common control valve 120, the electromagnetic switching valve 148, and the The gas is introduced into the rod side chamber of the span cylinder 106 through the selection valve 150 in order. With this hydraulic pressure supply, the span cylinder 106 contracts, and the width between the crawlers 20L and 20R is reduced.

  2) After fully pulling the arm 40 and raising the boom 38 fully, the arm 40 and the boom 38 are fully swung leftward together with the boom support member 36. By this operation, the forward protrusion amount of the boom 38 and the arm 40 is minimized. However, in FIG. 1 to FIG. 3, for convenience, the state where the swing is not performed is illustrated.

  3) Both the front and rear projecting members 50 and 52 are pulled up to the retracted position. Note that the front and rear switching valves 152 and 154 in the hydraulic circuit are switched to the front switching position in advance.

  4) The traveling remote control valve 124 is removed from the driver's seat 32 together with the operation box 160 and moved to a predetermined remote operation position.

  5) When the switching valves 128A and 128B are manually switched, these switching valves 128A and 128B are switched in advance to the escape position (the right side position in FIGS. 8 to 10), and both relief oil passages 126A, 126B is opened.

B. Stair Climbing After the preparation work is completed, the stairs 28 are climbed in the following procedure.

  1) Orient the self-propelled work machine 10 in a direction perpendicular to the stairs 28.

  2) Operate both travel levers 125L, 125R in the forward direction. By this operation, the pilot pressure from the pilot pump 104 is supplied to the forward pilot portions of the left travel control valve 115 and the right travel control valve 118 so that both control valves 115 and 118 are in the forward position side (upper position side in the figure). The oil discharged from the main pumps 101 and 102 is supplied to the left and right traveling motors through the traveling control valves 115 and 118.

  At this time, since the pilot pressure corresponding to the operation amount of the travel levers 125L and 125R is supplied to the pilot portion, the travel speed of the crawlers 20L and 20B increases as the operation amount increases. If the switching valves 128A and 128B are switched to the valve open position (release position) in advance, a part of the oil discharged from the main pumps 101 and 102 is released to the tank 108 through the release oil passages 126A and 126B. Even if the travel levers 125L and 125R of the remote control valve 124 are fully operated, the speed (maximum speed) at that time is lower than the speed during normal travel and reaches a speed suitable for stairs. Accordingly, it is possible to slowly climb the stairs 28 while fully operating both the travel levers 125L and 125R, thereby reducing the burden on the operator and ensuring high safety.

  The controller 156 determines whether or not the self-propelled working machine 10 is in the stairs ascending / descending, and the switching valves 128A and 128B are forcibly switched to the escape position when the stairs are ascending / descending, the following 3) As described above, the speed limit is automatically executed when the crawlers 20L and 20R start to climb the stairs 28, and higher safety is ensured.

  3) When the crawlers 20L and 20R ride on the first staircase 28 in the above-described manner, the entire self-propelled work machine 10 starts to tilt upward. From this point, the upper work body 16 is slightly moved with respect to the lower travel body 14. The upper work body 16 is kept substantially horizontal regardless of the inclination of the lower traveling body 14 by inclining forwardly downward (so-called draw operation). In order to perform such a drawing operation, the selection valve 150 in the hydraulic circuit shown in FIG. 8 is manually switched to the drawing selection position on the right side of the drawing, and in that state, the tuning switch 166 of the operation box 160 is turned on. The draw / span operation switch 163 may be operated to the “up” side with the switch off. Receiving the command signal output by this switch operation, the controller 156 switches on the solenoids a2 and b2 of the electromagnetic switching valves 148 and 134. As a result, the common control valve 120 is switched from the neutral position to the upper position in FIG. 8, and the hydraulic oil discharged from the main pump 102 flows from the center bypass flow path 112 to the common control valve 112 as indicated by a thick broken line in FIG. 120 and the electromagnetic switching valve 148 are sequentially introduced into the head side chamber of the upper work body operation cylinder 26 to extend the upper work body operation cylinder 26, and the upper work body 16 is moved relative to the lower traveling body 14. Tilt forward and downward.

  When the parallel operation of the draw operation and the forward operation of the lower traveling body 14 is completed and the entire crawlers 20L and 20R completely ride on the staircase 28, as shown in FIG. The upper working body 16 reaches an inclined position where the upper working body 16 is inclined with respect to the lower traveling body 14 by an equivalent angle θ, and the stairs 28 can be climbed while the upper working body 16 is maintained substantially horizontal.

C. Riding on the landing place The position immediately before the climbing and the landing on the landing place 29 (that is, as shown in FIG. When the position reaches the position where the center of gravity has not moved to the side), the crawlers 20L and 20R are temporarily stopped to stop the self-propelled work machine 10 and are then taken on the landing 29 in the following procedure.

  First, the front projecting member 50 is lowered from the retracted position to the projecting position, and the caster 54 is landed on the landing 29 as shown in FIG. In order to perform such an overhanging operation, the tuning switch 166 of the operation box 160 is turned off while the front and rear switching valves 152 and 154 are manually switched to the front switching position (lower position in FIG. 9) in advance. The caster operation switch 163 may be operated to the “down” side as it is.

  Next, while the traveling levers 125L and 125R are operated little by little to gradually advance the lower traveling body 14, the tuning switch 166 of the operation box 160 is turned on (that is, switched to the tuning control mode), and span / draw The operation switch 163 is operated to the “down” side or the caster operation switch 164 is operated to the “up” side to perform the automatic tuning operation. This automatic tuning operation is performed by switching on the solenoids a1, a2, b1 of the electromagnetic switching valves 147, 148, 133. Thereby, as shown by the thick line in FIG. 10, the hydraulic oil discharged from the main pump 102 is supplied to both the rod side chamber of the front projecting member operation cylinder 66 and the rod side chamber of the upper work body operation cylinder 26, The return operation of the upper work body 16 from the inclined position (FIG. 2) to the normal position (FIG. 3) due to the contraction of the upper work body operation cylinder 26 and the extension position of the front side extension member 50 due to the extension of the front side extension member operation cylinder 66. The storage operation is performed in synchronization with the storage position. In parallel with this synchronization operation, the lower traveling body 14 is moved forward slowly to keep the upper working body 16 in a substantially horizontal state, while keeping the lower traveling body 14 quiet (that is, the upper ends of the crawlers 20L and 20R are It is possible to completely get on the landing 29 as shown in FIG. 3 (while avoiding sudden landing on the landing 29).

  Also at this time, if the operating speed of the crawlers 20L and 20R associated with the operation of the travel levers 125A and 125B is limited, the timing of the return operation of the upper work body 16 and the retracting operation of the front projecting member 50 and the crawlers 20L and 20R Fine adjustment of the traveling speed for synchronizing the forward traveling is facilitated.

  In addition, when descending from the landing 29 to the stairs 28 in reverse to the climbing work, the reverse operation may be performed while the lower traveling body 14 is moved backward with the rear portion of the lower traveling body 14 facing the lower side of the stairs 28, Even in that case, high safety is ensured by limiting the reverse speed of the lower traveling body 14.

It is a side view which shows the state which the self-propelled working machine which concerns on embodiment of this invention is climbing up stairs. It is a side view which shows the state in which the said self-propelled working machine exists in the position just before riding on a landing from the said stairs. It is a side view which shows the state after the said self-propelled working machine gets on the said landing. It is a side view which shows the vehicle body frame of the said self-propelled working machine, and the front side extension member and rear side extension member attached to this. It is a top view which shows the said vehicle body frame and an overhang | projection member. (A) is a front view which shows the principal part of the said front side extension member, (b) is a front view which shows the principal part of the said back side extension member. It is a top view which shows the example which the said self-propelled working machine turns in a landing. It is a circuit diagram which shows the state in which hydraulic fluid is supplied to the rod side chamber of an upper work body operation cylinder in the hydraulic circuit mounted in the said self-propelled working machine. It is a circuit diagram which shows the state by which hydraulic fluid is supplied to the head side chamber of a front side extension member operation cylinder in the hydraulic circuit mounted in the said self-propelled working machine. The circuit diagram which shows the state by which hydraulic fluid is supplied to both the rod side chamber of the said upper working body operation cylinder and the head side chamber of the said extension member operation cylinder at the time of synchronous control in the hydraulic circuit mounted in the said self-propelled working machine It is. (A) is a top view of the operation box with which the said self-propelled working machine is equipped, (b) is the front view.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Self-propelled working machine 12 Scraper 14 Lower traveling body 16 Upper working body 18 Body frame 20L Left side crawler 20R Right side crawler 24 Relief frame 26 Upper working body operation cylinder 28 Stairs (slope)
29 landing (upper target)
101,102 Main pump (fluid pressure supply source)
104 Pilot pump 115 Left travel control valve 118 Right travel control valve 124 Travel remote control valve 125L, 125R Travel lever (travel operation member)
126A, 126B Relief oil passage 128A, 128B Switching valve 156 Controller (limit control means)

Claims (3)

When a traveling body capable of traveling on an inclined road, a traveling operation member for driving, traveling driving means for traveling the traveling body at a speed corresponding to an operation amount of the traveling operation member, and the traveling operation member are fully operated And a speed limiting means capable of switching between a restricted state for restricting the maximum traveling speed by the traveling driving means from that during normal traveling and an unrestricted state for releasing the restriction , the traveling driving means comprising a fluid pressure supply source And a fluid pressure actuator that receives the supply of working fluid from the fluid pressure supply source and operates the traveling body at a speed corresponding to the supply flow rate, and is provided between the fluid pressure supply source and the fluid pressure actuator. And a flow rate control valve that adjusts the flow rate of the working fluid supplied from the fluid pressure supply source to the fluid pressure actuator to a flow rate corresponding to the operation amount of the travel operation member. The means is provided separately from the flow rate control valve, and a first position for allowing a part of the working fluid supplied from the fluid pressure supply source to the fluid pressure actuator to escape and to be diverted to the flow path, and the first position. A self-propelled working machine comprising a switching valve that is switchable to a second position that restricts a flow rate of the working fluid to the escape passage rather than a position . 2. The self-propelled working machine according to claim 1, further comprising restriction control means for forcibly switching the speed restricting means to the restricted state at least when the ramp is moved up and down. 3. The self-propelled working machine according to claim 2 , wherein an upper working body is mounted on the traveling body, and the upper working body is in a normal position with respect to the traveling body and the ascending of the ramp from the normal position. The lower control body is supported by the lower traveling body so as to be relatively movable with respect to an inclined position inclined to the side, and the restriction control means controls the speed restriction means when the upper working body is not in the normal position. A self-propelled working machine that switches to the restricted state.

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