JP2007002893A - Work machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a work machine capable of securely switching between one-pedal operation by one leg and two-pedal operation by double legs without piping work. <P>SOLUTION: Pilot valves 33R and 33L for right and left legs are operated by right and left attachment operation pedals 28R and 28L installed on a frame, and a control valve 41 is pilot-operated by the pilot valves 33R and 33L to control a hydraulic actuator 3 for an attachment for operation. The work machine comprises a locking mechanism capable of selecting a locked state in which toe operation and heel operation by both right and left legs are disabled, a semi-locked state in which only heel operation is disabled, or an unlocked state in which both operations are enabled. The toe operation port 51 of the pilot valve 33R for right leg is allowed to communicate with one end side of a control valve 41, and the heel operation port 53 of the pilot valve 33R for right leg and the toe operation port 56 of he pilot valve 33L for left leg are allowed to selectively communicate with the other end side of the control valve through a shuttle valve 55. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a work machine provided with a work attachment used for dismantling, crushing, and the like.

  A work machine 1 shown in FIG. 7 is a dismantling specification machine adapted to work for dismantling a house or a building by using a work attachment 2 that is exchanged for a bucket in a hydraulic excavator. In such a work machine 1, the operation of the fluid pressure actuator 3 that opens and closes the work attachment 2 is controlled by operating a pedal-type pilot valve (hereinafter referred to as a remote control valve) that is usually installed at the feet of the operator. To do.

  For example, as shown in FIG. 8, there is usually only one pedal-type remote control valve 4, and this pedal-type remote control valve 4 is moved from the pilot pump 5 to the pilot 1 by moving the pedal back and forth or left and right using one foot. The pilot primary pressure supplied via the secondary pressure line 6 is controlled, and the controlled pilot secondary pressure is output from the two ports 7a and 7b to the control valve 9 via the pilot secondary pressure lines 8a and 8b. Thus, the direction and stroke of the control valve 9 are controlled, and the working fluid supplied from the main pump 10 to the fluid pressure actuator 3 of the work attachment 2 is controlled by the control valve 9 to control the direction and flow rate. 2 open / close operation and the like are controlled.

  In the operation of the pedal-type remote control valve 4, for example, when the pedal is moved back and forth, the foot toe and heel are continuously switched back and forth, so that the load on the foot is heavy and the foot becomes tired early. There is a possibility that.

  Depending on the model, there is room in the driver's seat, and as shown in Fig. 9, two pedal-type remote control valves 4a and 4b can be installed so that they can be operated with both left and right feet. The pilot primary pressure supplied from the pilot pump 5 through the pilot primary pressure line 6 is controlled by the pedal-type remote control valves 4a and 4b, and the pilot secondary pressure lines 8a and 8b are connected from the respective ports 7a and 7b. Then, by outputting the controlled pilot secondary pressure to the control valve 9, the control valve 9 is subjected to direction control and stroke control, and the control valve 9 supplies the fluid pressure actuator 3 of the work attachment 2 from the main pump 10. Direction control and flow control of the supplied working fluid are performed.

  Therefore, these one-pedal type (one-leg type) and two-pedal type (both-leg type) are not compatible on the same vehicle, so it is necessary to select one at the time of purchasing the aircraft, which is a rental machine used by many users. In this case, piping work for changing the piping shown in FIG. 8 and the piping shown in FIG. 9 is required, and labor is required for the piping work.

In addition, to reduce the burden on the foot, a foot pedal type operation valve (pedal type remote control valve) and an electromagnetic proportional pressure reducing valve (electromagnetic remote control valve) operated by a hand operation switch provided on the operation lever are used in combination. By doing this, there is one that enables both pedal operation and button operation without piping work (for example, see Patent Document 1).
Japanese Patent Laying-Open No. 2004-340187 (page 4-5, FIG. 1)

  Thus, the conventional work machine requires piping work to change the piping shown in FIG. 8 and the piping shown in FIG. 9, and the prior art described in Patent Document 1 Since the pedal operation and the button operation are not switched but used together, if these are operated simultaneously, a malfunction may occur.

  This invention is made in view of such a point, and it aims at providing the working machine which can switch reliably one pedal operation by one foot and two pedal operation by both feet, without piping construction. To do.

  The invention described in claim 1 includes an airframe, an arm-like working device attached to the airframe, a work attachment attached to the tip of the working device, and toes and heels of left and right feet provided on the airframe. The left foot attachment operation pedal and the right foot attachment operation pedal, the left foot pilot valve and the right foot pilot valve operated by these attachment operation pedals, and these pilot valves are used for pilot operation. A control valve that controls the operation of the work attachment, a locked state that disables toe operation and heel operation of the left and right attachment operation pedals, a semi-locked state that enables toe operation and disables heel operation, Locking with selectable unlocking state that allows toe and heel operation One toe operation port that outputs pilot pressure from one pilot valve by toe operation of one attachment operation pedal is connected to one end side of the control valve, and the heel of one attachment operation pedal is operated One heel operation port from which one pilot valve outputs pilot pressure and the other toe operation port from which the pilot pressure is output from the other pilot valve by the toe operation of the other attachment operation pedal are two of the shuttle valve. The working machine is in communication with the inlet port, and the outlet port of the shuttle valve is in communication with the other end of the control valve.

  The invention according to claim 2 is a machine body, an arm-like work device attached to the machine body, a work attachment attached to the tip of the work device, toes and heels of left and right feet provided on the machine body The left foot attachment operation pedal and the right foot attachment operation pedal, the left foot pilot valve and the right foot pilot valve operated by these attachment operation pedals, and these pilot valves are used for pilot operation. A control valve that controls the operation of the work attachment, a locked state that disables toe operation and heel operation of the left and right attachment operation pedals, a semi-locked state that enables toe operation and disables heel operation, Locking with selectable unlocking state that allows toe and heel operation The pilot pressure is output from one pilot valve by the toe operation of one attachment operation pedal. The pilot pressure is output from the other pilot valve by the heel operation of one toe operation port and the other attachment operation pedal. The other heel operation port is connected to two inlet ports of one shuttle valve, and the outlet port of this one shuttle valve is connected to one end side of the control valve to operate the heel of one attachment operation pedal. The pilot valve outputs the pilot pressure from one pilot valve, and the other toe operation port from which the pilot pressure is output from the other pilot valve by the toe operation of the other attachment operation pedal is connected to the other shuttle valve. Communicating with each of the two inlet ports , The outlet port of the other shuttle valve, a working machine communicating with the other end of the control valve.

  The invention according to claim 3 is a pin insertion plate in which the locking mechanism in the work machine according to claim 1 or 2 is fixedly arranged on one side and the other side via the attachment operation pedal, and the pin insertion plate, The toe operation of the attachment operation pedal and the toe operation of the attachment operation pedal are made possible by the locking pin insertion hole drilled at the locking position where the toe operation of the attachment operation pedal and the heel operation are impossible, and the pin insertion plate. A semi-locking pin insertion hole drilled at a semi-locking position and a pin insertion plate, and a pin drilled at a locking release position that enables toe operation and heel operation of the attachment operation pedal. The lock release pin insertion hole and the lock pin inserted by selecting one of the lock pin insertion hole, the semi-lock pin insertion hole, and the lock release pin insertion hole are provided.

  According to the first aspect of the present invention, the locking mechanism allows the toe operation and the heel operation of the left and right attachment operation pedals to be disabled, the toe operation is enabled, and the heel operation is disabled. The lock release state that enables the stop state, the toe operation, and the heel operation can be selected, and the toe operation port of one pilot valve communicates with one end side of the control valve, and the heel operation port of one pilot valve And the toe control port of the other pilot valve are connected to the two inlet ports of the shuttle valve, respectively, and the outlet port of this shuttle valve is connected to the other end of the control valve. And put the other pedal in the locked state so that the work attachment can be attached to the toe and heel of only one foot. In addition, the left and right pedals can be half-locked so that the work attachment can be operated with the toes of both the left and right feet. This allows one pedal operation with one foot and two with both feet without piping work. The pedal operation can be switched reliably, and the pedal operation according to the user's request can be set inexpensively and quickly.

  According to the second aspect of the present invention, the locking mechanism allows the toe operation and the heel operation of the left and right attachment operation pedals to be disabled, enables the toe operation, and prevents the heel operation from being performed. A stop state, a toe operation and an unlocked state enabling a heel operation can be selected, and a toe operation port of one pilot valve and a heel operation port of the other pilot valve are two inlets of one shuttle valve. The outlet port of one of the shuttle valves is in communication with one end of the control valve, and the heel operating port of one pilot valve and the toe operating port of the other pilot valve are connected to 2 of the other shuttle valve. One inlet port communicated with each other, and the other shuttle valve outlet port communicated with the other end of the control valve. (1) With one pedal in the unlocked state and the other pedal in the locked state, the work attachment can be operated with the toe and heel of only one foot, and (2) one pedal Is set to the locked state and the other pedal is set to the unlocked state so that the work attachment can be operated with the toes and heels of only the other foot, and (3) the left and right pedals are set to the half-locked state. Therefore, the work attachment can be operated with the toes of the right and left feet, and (4) the work attachment can be operated on the heels of both the left and right feet by releasing both the left and right pedals. Thus, one pedal operation with one foot and two pedal operations with both feet can be switched reliably, and the pedal operation according to the user's request can be set inexpensively and quickly.

  According to the third aspect of the present invention, by inserting and removing the locking pin in the locking pin insertion hole, the semi-locking pin insertion hole and the locking release pin insertion hole of the pin insertion plate, Switching between one pedal operation by and two pedal operations by both feet can be ensured.

  Hereinafter, the present invention will be described in detail with reference to one embodiment shown in FIGS. 1 to 5 and another embodiment shown in FIG. Note that the work machine 1 shown in FIG. 7 is also used in the description of the present invention.

  As shown in FIG. 7, the airframe 11 is formed by a crawler-type lower traveling body 12 and an upper revolving body 13 that is turnable with respect to the lower traveling 12 body. A cab 14 and an arm-like working device 15 that protect the operator are mounted.

  This operating device 15 has a boom 15bm pivotally supported on the upper swing body 13 by a boom cylinder 15bmc so that it can pivot in the vertical direction, and an arm 15am pivotally supported by an arm cylinder 15amc on the tip of the boom 15bm. A work attachment 2 replaced with a bucket is pivotally supported by a bucket cylinder 15bkc and attached to the tip of the bucket.

  This work attachment 2 is an attachment for house dismantling, scrap processing, industrial waste processing, masonry work or forestry, and a pair of gripping bodies 17 are pivotally supported by the main body 16 so as to be freely opened and closed. A pair of gripping bodies 17 are driven to open and close by a fluid pressure actuator 3 that is expanded and contracted by fluid pressure (hydraulic pressure) supplied from the machine body 11 and, if necessary, a gripping body interlocking mechanism (not shown). Here, it is assumed that the gripping body 17 is closed by the extension operation of the fluid pressure actuator 3.

  As shown in FIG. 2, in the cab 14, an operator seating seat 22 is provided on a platform 21 that constitutes a part of the airframe 11, and console boxes 23 are arranged on the left and right sides of the seat 22, respectively. Work control levers 24 project from the front ends of these console boxes 23, and a pair of left and right travel pedals 25 and 26 are arranged in front of the seat 22, respectively. Footrests 27 are arranged on the left and right sides of the footrest, respectively, and an attachment operation pedal 28L for the left foot and an attachment operation pedal 28R for the right foot are respectively arranged on the left and right outer sides of the footrest 27.

  The left foot attachment operation pedal 28L and the right foot attachment operation pedal 28R swing on the upper part of the pilot valve 33 fixed to the platform 21 by a bolt 32 via a mounting plate 31 as shown in FIG. It is pivotally supported by a support shaft 34, and the toe operation part 35 and the heel operation part 36 are provided so as to be swingable by the toes and heels of the left and right feet, with these swing support axes 34 as fulcrums. ing. A mounting plate 37 is integrally provided below the attachment operation pedals 28L and 28R, and a bellows cover 38 is provided between the mounting plate 37 and the main body of the pilot valve 33.

  As shown in FIG. 1, the left foot pilot valve 33 </ b> L and the right foot pilot valve 33 </ b> R operated by these attachment operation pedals 28 </ b> L and 28 </ b> R are controls that control the operation of the fluid pressure actuator 3 of the work attachment 2. The valve 41 is pilot operated. The control valve 41 includes a spool that controls the direction and flow rate of the working fluid that is supplied from the main pump 42 to the fluid pressure actuator 3 and returned from the fluid pressure actuator 3 to the tank 43.

  Each of the left foot pilot valve 33L and the right foot pilot valve 33R includes a pressure reducing valve 44 operated by a toe and a pressure reducing valve 45 operated by a heel, and the pilot primary pressures of these pressure reducing valves 44, 45 are provided. A pilot pump 47 is connected to the line 46, and a return line 48 is connected to the tank 43.

  One toe operation port 51 through which the pilot pressure is output from the right foot pilot valve 33R by the toe operation of the right foot attachment operation pedal 28R is connected to one end of the spool of the control valve 41 via the pilot line 52.

  On the other hand, the heel operation port 53 of the right foot, where the pilot pressure is output from the right foot pilot valve 33R by the heel operation of the attachment pedal 28R for the right foot, passes through the pilot line 54 to one inlet port 55iR of the shuttle valve 55. The other toe operation port 56, which is communicated and the pilot pressure is output from the left foot pilot valve 33L by the toe operation of the left foot attachment operation pedal 28L, is connected to the other inlet of the shuttle valve 55 via the pilot line 57. The shuttle port 55 communicates with the port 55iL, and the outlet port 55o of the shuttle valve 55 communicates with the other end of the spool of the control valve 41 via the pilot line 58.

  The other heel operation port 59 through which the pilot pressure is output from the left foot pilot valve 33L by the heel operation of the left foot attachment operation pedal 28L is communicated with the tank 43.

  As shown in FIGS. 3 and 4, on the lower side of the toe operation portion 35 of the left and right attachment operation pedals 28L and 28R, a locking mechanism 61 for releasably locking these attachment operation pedals 28L and 28R. Are installed. These locking mechanisms 61 are a locked state in which the toe operation and the heel operation of the left and right attachment operation pedals 28L and 28R are impossible, a toe operation is possible, a semi-locked state in which the heel operation is impossible, and a toe An unlocking state that enables operation and heel operation can be selected.

  The left and right locking mechanisms 61 are configured such that pin insertion plates 62 bent into a concave shape by sheet metal are fixedly arranged on the platform 21 below the toe operation portions 35 of the attachment operation pedals 28L and 28R. In the pin insertion plate 62, a locking pin insertion hole A is drilled at a locking position where the toe operation and the heel operation of the attachment operation pedals 28L and 28R are impossible. A semi-locking pin insertion hole B is drilled at a semi-locking position where the toe operation of the attachment operation pedals 28L and 28R is possible and the heel operation is impossible. An unlocking pin insertion hole C is formed at an unlocking position that enables toe operation and heel operation of 28L and 28R.

  One of the locking pin insertion hole A, the half locking pin insertion hole B, and the locking release pin insertion hole C is selected by the chain 63 connected to the pin insertion plate 62. Pin 64 is inserted.

  The attachment plates 37 of the left and right attachment operation pedals 28L and 28R are respectively provided with locking holes a through which the locking pins 64 inserted into the locking pin insertion holes A are inserted, and for semi-locking. A long hole b through which the locking pin 64 inserted into the pin insertion hole B is inserted is formed.

  FIG. 5 shows an attachment operation explanation plate 65 of the work machine. One pedal operation on the right side using only the attachment operation pedal 28R, two left and right pedal operations using the left and right attachment operation pedals 28L and 28R, and left and right attachment operation pedals 28L and 28R. This represents the relationship between the pedal lock that secures the hook and the insertion position (lock pin position) of the locking pin 64 in the left and right attachment operation pedals 28L and 28R, as well as the toe and heel operations and the work attachment 2 is a grapple It represents the relationship with the grapple opening and closing direction.

  Next, the function and effect of the embodiment shown in FIGS. 1 to 5 will be described.

  The attachment operation pedals 28L and 28R are formed by inserting the locking pin 64 into the locking pin insertion hole A of the pin insertion plate 62 and the locking hole a of the mounting plate 37 (hereinafter referred to as “A position”). Since operation | movement can be locked, it can respond to the case where the work attachment 2 is not installed (for example, mounting | wearing with a bucket).

  The attachment operation pedals 28L and 28R are arranged in such a way that when the locking pin 64 is inserted into the semi-locking pin insertion hole B of the pin insertion plate 62 and the long hole b of the mounting plate 37 (hereinafter referred to as “B position”), Attachment opening and closing operations are possible by toe operation of the pedals on both sides.

  The attachment operation pedals 28L and 28R can be operated by one-side pedal toe operation and heel operation by inserting the locking pin 64 into the locking release pin insertion hole C (hereinafter referred to as "C position") of the pin insertion plate 62. The attachment opening / closing operation can be performed.

  Therefore, by inserting the locking pin 64 at the C position for the right foot and inserting the locking pin 64 at the A position for the left foot, the work attachment 2 can be opened and closed by the toe operation and the heel operation of only the right foot. . That is, the control valve 41 is switched to the right chamber by the pilot pressure output to the spool one end side of the control valve 41 from the toe operation port 51 through the pilot line 52 by the toe operation of the right foot, and the rod side of the fluid pressure actuator 3 The working fluid 2 is supplied to open the work attachment 2, and the pilot pressure output from the heel operation port 53 to the other end of the spool of the control valve 41 via the shuttle valve 55 and the pilot line 58 by the heel operation of the right foot. Thus, the working valve 2 can be closed by switching the control valve 41 to the left chamber and supplying the working fluid to the head side of the fluid pressure actuator 3. That is, the right foot toe operation can be set as “attachment open”, and the right foot heel operation can be set as “attachment close”.

  Further, by inserting the locking pins 64 at the left and right B positions, the work attachment 2 can be opened and closed by operating the toes of the left and right feet. That is, the control valve 41 is switched to the right chamber by the pilot pressure output to the spool one end side of the control valve 41 from the toe operation port 51 through the pilot line 52 by the toe operation of the right foot, and the rod side of the fluid pressure actuator 3 The working fluid 2 is supplied to open the work attachment 2, and the pilot pressure output from the toe operation port 56 to the other end of the spool of the control valve 41 via the shuttle valve 55 and the pilot line 58 by the toe operation of the left foot. Thus, the working valve 2 can be closed by switching the control valve 41 to the left chamber and supplying the working fluid to the head side of the fluid pressure actuator 3. That is, the right foot toe operation can be set as “attachment open”, and the left foot toe operation can be set as “attachment close”.

  Accordingly, one pedal operation with one foot and two pedal operations with both feet can be reliably switched without piping work, and the pedal operation according to the user's request can be set inexpensively and quickly.

  Next, FIG. 6 shows another embodiment. The pedal arrangement and locking mechanism 61 shown in FIGS. 2 to 4 and the work machine 1 shown in FIG. 7 are also applied to the embodiment shown in FIG.

  That is, the machine body 11 shown in FIG. 7, the arm-like work device 15 attached to the machine body 11, the work attachment 2 attached to the tip of the work device 15, and FIGS. 2 to 4 Left foot attachment operation pedal 28L and right foot attachment operation pedal 28R and left and right attachment operation pedals 28L and 28R toe operation and heel A locking mechanism 61 capable of selecting a locking state that disables the operation, a toe operation, a semi-locking state that disables the heel operation, and a locking release state that enables the toe operation and the heel operation; Since the point provided with is the same, detailed description is omitted.

  As shown in FIG. 6, the left foot pilot valve 33L operated by the left foot attachment operation pedal 28L and the right foot pilot valve 33R operated by the right foot attachment operation pedal 28R pilot the control valve 41. This control valve 41 includes a spool that controls the direction and flow rate of the working fluid that is supplied from the main pump 42 to the fluid pressure actuator 3 of the work attachment 2 and returned from the fluid pressure actuator 3 to the tank 43. The operation of the fluid pressure actuator 3 is controlled.

  Each of the left foot pilot valve 33L and the right foot pilot valve 33R includes a pressure reducing valve 44 operated by a toe and a pressure reducing valve 45 operated by a heel, and the pilot primary pressures of these pressure reducing valves 44, 45 are provided. A pilot pump 47 is connected to the line 46, and a return line 48 is connected to the tank 43.

  One toe operation port 51 from which pilot pressure is output from the right foot pilot valve 33R by the toe operation of the right foot attachment operation pedal 28R passes through the pilot line 71 to one inlet port 55aR of one shuttle valve 55a. The other heel operation port 59 that is communicated and the pilot pressure is output from the left foot pilot valve 33L by the heel operation of the left foot attachment operation pedal 28L is connected to the other of the one shuttle valve 55a via the pilot line 72. The outlet port 55ao of the shuttle valve 55a communicates with one end of the spool of the control valve 41 via the pilot line 52.

  On the other hand, one heel operation port 53 through which the pilot pressure is output from the right foot pilot valve 33R by the heel operation of the right foot attachment operation pedal 28R passes through the pilot line 54 and one inlet port of the other shuttle valve 55b. The other toe operation port 56 that communicates with 55bR and outputs pilot pressure from the left foot pilot valve 33L by the toe operation of the left foot attachment operation pedal 28L is connected to the other shuttle valve 55b via the pilot line 57. The other inlet port 55bL of the shuttle valve 55b communicates with the outlet port 55bo of the shuttle valve 55b through the pilot line 58 to the other end of the spool of the control valve 41.

  In short, the embodiment shown in FIG. 1 described above cannot operate the left foot heel, but the embodiment shown in FIG. 6 includes the toe operation port 51 for the right foot, the heel operation port 59 for the left foot, Are connected by another shuttle valve 55a different from the shuttle valve 55 shown in FIG. 1, and the heel operation of the left foot is “attachment opening”.

  Next, the function and effect of the embodiment shown in FIG. 6 will be described.

  The attachment operation pedals 28L and 28R can lock the pedal operation when the locking pin 64 is inserted in the A position, so that it is possible to cope with the case where the work attachment 2 is not installed (for example, a bucket is attached). When the locking pin 64 is inserted into the B position, the attachment can be opened and closed by the toe operation of the left and right pedals. When the locking pin 64 is inserted at the C position, the attachment is opened and closed by the toe operation and the heel operation of the one side pedal. Operation becomes possible.

  Therefore, (1) by inserting the locking pin 64 at the C position for the right foot and inserting the locking pin 64 at the A position for the left foot, the work attachment 2 can be attached by the toe operation and the heel operation of only the right foot. Can be opened and closed. That is, when the toe of the right foot is operated, the control valve 41 is switched to the right chamber by the pilot pressure output from the toe operation port 51 to the spool one end of the control valve 41 through the shuttle valve 55a and the pilot line 52, and the fluid pressure actuator The working fluid 2 is supplied to the rod side of 3 to open the work attachment 2 and output to the other end of the spool of the control valve 41 from the heel operation port 53 via the shuttle valve 55b and the pilot line 58 by the heel operation of the right foot. The control valve 41 is switched to the left chamber by the pilot pressure thus applied, and the working fluid 2 can be closed by supplying the working fluid to the head side of the fluid pressure actuator 3. That is, the right foot toe operation can be set as “attachment open”, and the right foot heel operation can be set as “attachment close”.

  (2) Inserting the locking pin 64 at the A position for the right foot and inserting the locking pin 64 at the C position for the left foot allows the work attachment 2 to be opened and closed by the toe operation and heel operation of the left foot only. it can. That is, when the heel operation of the left foot is performed, the control valve 41 is switched to the right chamber by the pilot pressure output from the heel operation port 59 to the spool one end side of the control valve 41 through the shuttle valve 55a and the pilot line 52, and the fluid pressure actuator The working fluid is supplied to the rod side of 3 to open the work attachment 2, and the toe operation of the left foot is output from the toe operation port 56 to the other end of the spool of the control valve 41 via the shuttle valve 55 b and the pilot line 58. The control valve 41 is switched to the left chamber by the pilot pressure thus applied, and the working fluid 2 can be closed by supplying the working fluid to the head side of the fluid pressure actuator 3. That is, the left foot heel operation can be set as “attachment open”, and the left foot toe operation can be set as “attachment close”.

  (3) By inserting the locking pin 64 into each B position of the left and right attachment operation pedals 28L and 28R, the work attachment 2 can be opened and closed by each toe operation of the right and right feet. That is, when the toe of the right foot is operated, the control valve 41 is switched to the right chamber by the pilot pressure output from the toe operation port 51 to the spool one end of the control valve 41 through the shuttle valve 55a and the pilot line 52, and the fluid pressure actuator The working fluid is supplied to the rod side of 3 to open the work attachment 2, and the toe operation of the left foot is output from the toe operation port 56 to the other end of the spool of the control valve 41 via the shuttle valve 55 b and the pilot line 58. The control valve 41 is switched to the left chamber by the pilot pressure thus applied, and the working fluid 2 can be closed by supplying the working fluid to the head side of the fluid pressure actuator 3. That is, the right foot toe operation can be set as “attachment open”, and the left foot toe operation can be set as “attachment close”.

  (4) By inserting the locking pin 64 into each position C of the left and right attachment operation pedals 28L and 28R, the work attachment 2 can be opened and closed even by operating the heels of the left and right feet. That is, when the heel operation of the left foot is performed, the control valve 41 is switched to the right chamber by the pilot pressure output from the heel operation port 59 to the spool one end side of the control valve 41 through the shuttle valve 55a and the pilot line 52, and the fluid pressure actuator The working fluid 2 is supplied to the rod side of 3 to open the work attachment 2 and output to the other end of the spool of the control valve 41 from the heel operation port 53 via the shuttle valve 55b and the pilot line 58 by the heel operation of the right foot. The control valve 41 is switched to the left chamber by the pilot pressure thus applied, and the working fluid 2 can be closed by supplying the working fluid to the head side of the fluid pressure actuator 3. That is, the left heel heel operation can be set as “attachment open”, and the right heel heel operation can be set as “attachment close”.

  In this way, the two left and right attachment operation pedals 28L and 28R can be used at low cost without rearranging the piping or using the rotary valve (selection valve), and the attachment operation pedals 28L and 28R on both the left and right sides can be attached. It is possible to easily switch between one pedal operation with one foot and two pedal operation with both feet by attaching and detaching one locking pin 64 on each of the left and right sides, and meeting the user's request at a low cost and quickly. Pedal operation can be set.

  In each embodiment, one toe operation port 51 and one heel operation port 53 are provided in the right foot pilot valve 33R, and the other toe operation port 56 and the other heel operation port 59 are the left foot pilot valve. Although provided in 33L, these relationships may be reversed. That is, one toe operation port 51 and one heel operation port 53 may be provided in the left foot pilot valve 33L, and the other toe operation port 56 and the other heel operation port 59 may be provided in the right foot pilot valve 33R. .

  The present invention can be used in a dismantling machine, a crusher, a crusher, a cutting machine, and the like equipped with various attachments such as a hydraulic breaker, a cutter (puncher), and a grapple. Accordingly, one-pedal operation with one foot and two-pedal operation with both feet can be reliably switched without piping work.

1 is a fluid pressure circuit diagram showing an embodiment of an attachment operation circuit for a work machine according to the present invention. It is a perspective view which shows the inside of the cab of a working machine same as the above. It is a perspective view which shows the attachment operation pedal of a working machine same as the above. It is a side view which shows the attachment operation pedal of a working machine same as the above. It is a front view which shows the attachment operation explanatory plate of a working machine same as the above. It is the fluid pressure circuit diagram which shows other embodiment of the attachment operation circuit of the working machine which concerns on this invention. It is a side view of a working machine same as the above. It is a fluid pressure circuit diagram which shows an example of the attachment operation circuit of the conventional working machine. It is the fluid pressure circuit diagram which shows the other example of the attachment operation circuit of the conventional working machine.

Explanation of symbols

2 Work attachment
11 Aircraft
15 Work equipment
Attachment control pedal for 28L left foot
28R Attachment pedal for right foot
33L Pilot valve for left foot
33R Pilot valve for right foot
41 Control valve
51 One toe operation port
53 One heel operation port
55 Shuttle valve
55iL, 55iR inlet port
55o outlet port
55a One shuttle valve
55aL, 55aR inlet port
55ao exit port
55b The other shuttle valve
55bL, 55bR inlet port
55bo outlet port
56 Other toe control port
59 Other heel operation port
61 Locking mechanism
62 pin insertion plate
64 Locking pin A Locking pin insertion hole B Semi-locking pin insertion hole C Unlocking pin insertion hole

Claims (3)

The aircraft,
An arm-like working device attached to this aircraft,
A working attachment attached to the tip of the working device;
An attachment operation pedal for the left foot and an attachment operation pedal for the right foot, each of which can be operated by the toes and heels of the left and right feet provided on the aircraft,
A pilot valve for the left foot and a pilot valve for the right foot operated by these attachment operation pedals;
A control valve piloted by these pilot valves to control the operation of the work attachment;
Locking state that disables toe operation and heel operation of the left and right attachment operation pedals, and toe operation, semi-locking state that disables heel operation, unlocking that allows toe operation and heel operation A locking mechanism capable of selecting a state,
One toe operation port from which pilot pressure is output from one pilot valve by toe operation of one attachment operation pedal is communicated with one end side of the control valve,
Pilot pressure is output from one pilot valve by the heel operation of one attachment operation pedal The other toe operation is output from the other pilot valve by the toe operation of one heel operation port and the other attachment operation pedal Port to the two inlet ports of the shuttle valve,
A work machine characterized in that the outlet port of the shuttle valve communicates with the other end of the control valve. The aircraft,
An arm-like working device attached to this aircraft,
A working attachment attached to the tip of the working device;
An attachment operation pedal for the left foot and an attachment operation pedal for the right foot, each of which can be operated by the toes and heels of the left and right feet provided on the aircraft,
A pilot valve for the left foot and a pilot valve for the right foot operated by these attachment operation pedals;
A control valve piloted by these pilot valves to control the operation of the work attachment;
Locking state that disables toe operation and heel operation of the left and right attachment operation pedals, and toe operation, semi-locking state that disables heel operation, unlocking that allows toe operation and heel operation A locking mechanism capable of selecting a state,
The pilot pressure is output from one pilot valve by the toe operation of one attachment operation pedal. The heel operation of the other pilot valve is output from the other pilot valve by the heel operation of one toe operation port and the other attachment operation pedal. Port communicates with the two inlet ports of one shuttle valve,
The outlet port of this one shuttle valve communicates with one end of the control valve,
Pilot pressure is output from one pilot valve by the heel operation of one attachment operation pedal The other toe operation is output from the other pilot valve by the toe operation of one heel operation port and the other attachment operation pedal Each port communicates with the two inlet ports of the other shuttle valve,
A work machine characterized in that the outlet port of the other shuttle valve communicates with the other end of the control valve. The locking mechanism is
A pin insertion plate fixedly arranged on one side and the other side via an attachment operation pedal;
A pin insertion hole for locking that is drilled at a locking position that makes the toe operation of the attachment operation pedal and the heel operation impossible with the pin insertion plate,
A pin insertion hole for semi-locking that is drilled in a semi-locking position that enables toe operation of the attachment operation pedal and makes heel operation impossible with the pin insertion plate,
A pin insertion hole for unlocking that is drilled at an unlocking position that enables toe operation and heel operation of the attachment operation pedal with the pin insertion plate,
The locking pin inserted by selecting one of the locking pin insertion hole, the semi-locking pin insertion hole, and the locking release pin insertion hole, according to claim 1 or 2. Work machine.

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