JP2019056217A - Working vehicle - Google Patents

Abstract

To provide a configuration capable of easily recognizing a present operating condition with excellent operability for a working vehicle selectably switching in traveling speed steps.SOLUTION: A revolving work vehicle 1 is provided with work control levers 53L, 53R, a control box 52, and a change-over switch 55 of traveling speed steps. The work control levers 53L, 53R are arranged respectively at each of both sides of a driving seat 51. The control box 52 is arranged to project upward on a forward floor surface of the driving seat 51. The change-over switch 55 of traveling speed steps is operated by an operator to change traveling speeds. The change-over switch 55 of traveling speed steps is arranged on an upper part of the control box 52.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a work vehicle capable of switching a traveling speed stage.

  2. Description of the Related Art Conventionally, work vehicles that can travel by switching the traveling speed between two stages of a low speed stage and a high speed stage are known. Patent Documents 1 and 2 disclose this type of work vehicle.

  The backhoe disclosed in Patent Literature 1 includes a traveling speed change / PTO driving pedal. When the pedal is not operated at all, the PTO is in a neutral state and the traveling speed is the first speed. When the left side of the pedal is depressed, the PTO is in a neutral state and the traveling gear is set to the second gear. The state in which the right side of the pedal is depressed is the driving state of the PTO unit, and at this time, the traveling gear stage is the first speed stage.

  In the turning work machine disclosed in Patent Document 2, a pair of left and right control levers are supported on the control frame so as to protrude upward. A dozer lever for moving the dozer up and down is provided on the side of one control lever. On the head of the dozer lever, a switch for changing the traveling speed to the second speed is provided.

JP-A-8-151664 JP 2007-239304 A

  However, in the configuration of Patent Document 1, only one operation of forward rotation or inversion of the PTO can be assigned to the traveling speed change / PTO driving pedal. Therefore, when driving a double-acting type actuator with PTO, assignment such as forward rotation drive when one of the pedals is stepped on and reverse rotation drive when the other side is stepped on cannot be performed. It is difficult to realize. In addition, since the traveling transmission and PTO driving pedal is disposed at the foot, it is difficult to visually confirm the speed switching state unless the operator looks into the foot.

  Further, in the configuration of Patent Document 2 described above, a switch for switching the traveling speed stage is arranged at the head of the dozer lever, so that the switch tends to be small due to the arrangement space, and the visibility of the switching state of the switch Is not necessarily excellent. On the other hand, if you want to install a large switch with good visibility on the head of the dozer lever, you will have to increase the size of the grip of the dozer lever. Using a large grip can be difficult.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a configuration that is excellent in operability and can easily check the current operation state in a work vehicle capable of switching the traveling speed stage. There is to do.

Means and effects for solving the problems

  The problems to be solved by the present invention are as described above. Next, means for solving the problems and the effects thereof will be described.

  According to an aspect of the present invention, a work vehicle having the following configuration is provided. That is, this work vehicle includes an operation lever, a control box, and a traveling speed stage switching device. The operation lever is disposed on each of the left and right sides of the driver seat. The control box is provided so as to protrude upward on a floor surface in front of the driver seat. The travel speed stage switching device is operated by an operator to switch the travel speed stage. The traveling speed stage switching device is provided in the upper part of the control box.

  Thus, by providing the traveling speed stage switching device at a position where the operator sitting on the driver's seat can visually recognize, the operator can easily confirm the operation state of the high speed stage / low speed stage. In addition, by arranging the travel speed stage switching device in the control box in front of the driver's seat, the operator can switch the travel speed stage with either the left or right hand, and the degree of freedom of operation can be improved. .

  In the work vehicle, it is preferable that a display device that displays an operation state of the traveling speed stage switching device is disposed in the control box.

  Thereby, the visibility of the switching state of the traveling speed stage can be further improved.

  The work vehicle preferably has the following configuration. That is, the work vehicle includes a travel lever disposed in the control box. The travel speed stage switching device is disposed at a position displaced from the travel lever in the left-right direction of the control box.

  Thus, the operator can operate the travel speed stage switching device with the opposite hand while operating the travel lever with one hand. That is, the convenience of two-handed operation can be improved.

  The work vehicle preferably has the following configuration. That is, the work vehicle includes a first port and a second port for driving the attachment work machine, and a foot pedal. The foot pedal is used by an operator to operate the attachment work machine with his / her foot. When the foot pedal is operated from the neutral position to one side, the hydraulic oil is supplied to the first port, and when operated to the opposite side, the hydraulic oil is supplied to the second port.

  Thereby, for example, when the attachment work machine includes a double-action cylinder, the double-action cylinder can be operated by stepping one foot pedal to one side / the other side. Therefore, an intuitive and easy-to-understand operational feeling can be realized.

The side view which shows the structure of the turning working vehicle which concerns on one Embodiment of this invention. The perspective view which shows the structure of the turning working vehicle of this embodiment. The figure which shows typically the hydraulic circuit of a turning work vehicle. The elements on larger scale which show the structure of a traveling speed stage changeover switch.

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a side view showing a configuration of a turning work vehicle 1 according to an embodiment of the present invention. FIG. 2 is a perspective view showing the configuration of the turning work vehicle 1. In the following description, “front”, “rear”, “left”, and “right” refer to the operator sitting on the driver's seat 51 in a state in which the front of the lower traveling body 11 and the front of the upper swinging body 12 described later are aligned. It means front, rear, left and right.

  A turning work vehicle (working vehicle) 1 shown in FIG. 1 is a small backhoe, and mainly includes a lower traveling body 11 and an upper turning body 12.

  The lower traveling body 11 includes a pair of left and right crawler traveling devices 21 and a hydraulic motor 22. As shown in FIG. 2, the hydraulic motor 22 is provided in each of the left and right crawler travel devices 21. The lower traveling body 11 can drive the left and right crawler traveling devices 21 individually in various directions and speeds, and can perform various traveling such as straight traveling forward or backward, steering, and the like.

  As shown in FIG. 1, the upper swing body 12 includes a swing frame 31, an engine 33, a hydraulic pump unit 34, a bonnet 38, a control unit 35, and a work device 13.

  The turning frame 31 is disposed above the lower traveling body 11 and supported by the lower traveling body 11 so as to be rotatable about a vertical axis. The turning frame 31 can rotate with respect to the lower traveling body 11 by driving the turning motor 32. The engine 33 is configured as a diesel engine, for example, and is disposed at the rear portion of the turning frame 31. The hydraulic pump unit 34 is driven by the engine 33 and generates oil pressure necessary for traveling and working of the turning work vehicle 1.

  The control unit 35 includes a driver's seat 51 on which an operator sits, a control box 52 erected in front of the driver's seat 51, and various operation members. Examples of the operation members include work operation levers (operation levers) 53L and 53R installed on the left and right sides of the driver seat 51, travel levers 54L and 54R supported by the control box 52, travel speed stage changeover switch (travel Speed stage switching device) 55, power take-out pedal (foot pedal) 56, and the like.

  As shown in FIG. 2, the control box 52 is provided so as to protrude upward from the floor surface in front of the driver seat 51. On the upper surface, a traveling speed stage changeover switch 55, traveling levers 54L and 54R, and various display devices are arranged.

  The travel levers 54L and 54R are arranged side by side in the left-right direction on the upper surface of the control box 52 on the side close to the driver seat 51 and on the left-right center. The two traveling levers 54L and 54R are disposed close to each other in the left-right direction, and are supported so as to protrude upward from the upper surface of the control box 52, respectively. The operator can instruct the left and right crawler traveling devices 21 to move forward or backward by tilting the left and right traveling levers 54L and 54R forward or backward.

  The traveling speed stage changeover switch 55 is configured by an electric switch, specifically, a rocker switch with a fulcrum shaft directed in the left-right direction. The operator can switch the attitude of the switch like a seesaw by pressing the end of the traveling speed stage changeover switch 55. When the travel speed stage changeover switch 55 is in the rearward lowered position, the contact is closed, and when it is in the forward lowered position, the contact is opened. The operator instructs the high speed stage (second speed) by turning on the traveling speed stage changeover switch 55 and instructs the low speed stage (first speed) by turning it off.

  The power take-out pedal 56 is disposed slightly above the floor surface in front of the driver seat 51 and on the left side of the control box 52. The power take-out pedal 56 is operated by an operator stepping on his / her foot in order to drive an unillustrated attachment working machine (for example, an attachment for mowing). A first port 81 and a second port 82 for supplying hydraulic oil for driving the attachment work machine are provided at appropriate positions of the turning work vehicle 1. In this embodiment, the 1st port 81 and the 2nd port 82 are arrange | positioned at the boom 61 in the below-mentioned working device 13, as shown in FIG.

  The power take-out pedal 56 displaces a direction switching valve included in the turning work vehicle 1 in order to switch the direction of the hydraulic oil via a link mechanism (not shown) including an arm and a rod. Details of the direction switching valve will be described later. As a result, the hydraulic oil can be discharged from either the first port 81 or the second port 82 in conjunction with the operation of the operator depressing the power take-out pedal 56 forward / backward.

  The work device 13 includes a boom 61, an arm 62, a bucket 63, a boom cylinder 64, an arm cylinder 65, and a bucket cylinder 66.

  The boom 61 is configured as an elongated member, and an end portion thereof is rotatably supported by the front portion of the upper swing body 12. A boom cylinder 64 is attached to the boom 61, and the boom 61 can be rotated by expanding and contracting the boom cylinder 64.

  The arm 62 is configured as an elongated member, and an end portion of the arm 62 is rotatably supported by the tip end portion of the boom 61. An arm cylinder 65 is attached to the arm 62, and the arm 62 can be rotated by expanding and contracting the arm cylinder 65.

  The bucket 63 is configured as a member formed in a container shape, and an end portion of the bucket 63 is rotatably supported by a distal end portion of the arm 62. A bucket cylinder 66 is attached to the bucket 63, and the bucket 53 can be rotated by the expansion and contraction of the bucket cylinder 66 to perform a scooping operation / dumping operation.

  Next, a hydraulic circuit provided in the turning work vehicle 1 of the present embodiment will be described. FIG. 3 is a diagram schematically showing a hydraulic circuit of the turning work vehicle 1.

  As shown in FIG. 3, the hydraulic pump unit 34 includes two variable displacement hydraulic pumps 34a and 34b and an auxiliary hydraulic pump 34c. The turning work vehicle 1 includes a first hydraulic circuit 9a and a second hydraulic circuit 9b. The first hydraulic circuit 9a is supplied with hydraulic oil from one hydraulic pump 34a, and the second hydraulic circuit 9b is supplied with hydraulic oil from the other hydraulic pump 34b.

  The first hydraulic circuit 9a is connected to a hydraulic motor 22L that drives the crawler traveling device 21 disposed on the left side of the vehicle body. A direction switching valve 91 is disposed between the hydraulic motor 22L and the discharge port of the hydraulic pump 34a.

  A hydraulic motor 22R that drives the crawler traveling device 21 disposed on the right side of the vehicle body and an attachment cylinder 90 that drives the attachment working machine are connected to the second hydraulic circuit 9b. The attachment cylinder 90 is a double acting cylinder and is connected to the first port 81 and the second port 82 described above. Direction switching valves 92 and 93 are disposed between the discharge port of the hydraulic pump 34b and the hydraulic motor 22R and the attachment cylinder 90, respectively.

  Although omitted in FIG. 3, the first hydraulic circuit 9a and the second hydraulic circuit 9b are connected to another hydraulic actuator for driving the working device 13 and the like.

  In each of the directional control valves 91 and 92 connected to the left and right hydraulic motors 22L and 22R, the spool is displaced to one side from the neutral position where the supply of pressure oil is stopped, so that the hydraulic motors 22L and 22R are rotated forward. And reverse by displacing to the other side.

  Each of the pair of traveling levers 54L and 54R can individually instruct forward, backward and stop of the left and right crawler traveling devices 21. The operator instructs to move forward by tilting the traveling levers 54L and 54R forward from the neutral position, and instructs backward by tilting the traveling levers 54L and 54R backward.

  The turning work vehicle 1 includes remote control valves 95L and 95R arranged corresponding to the pair of travel levers 54L and 54R. Each of the remote control valves 95L and 95R has two output ports, and hydraulic oil having a pressure corresponding to the operation amount can be sent to a port corresponding to the operation direction (forward / reverse) of the travel levers 54L and 54R. it can. Pilot pressures output from the remote control valves 95L and 95R are guided to the pilot ports of the direction switching valves 91 and 92 described above. Accordingly, the spools of the direction switching valves 91 and 92 are displaced by a direction and an amount corresponding to the traveling direction and the traveling speed instructed by the traveling levers 54L and 54R, thereby causing the hydraulic motors 22L and 22R to be instructed by the operator. It can be rotated with the direction and speed based.

  Further, the spool of the direction switching valve 93 is connected to the power take-out pedal 56 via the aforementioned link mechanism. Accordingly, the spool of the direction switching valve 93 is displaced by the direction and the amount corresponding to the direction and the operation amount indicated by the power take-out pedal 56, whereby the attachment cylinder 90 is moved in the direction and the amount based on the operator's instruction. It can be operated.

  As shown in FIG. 3, the hydraulic pump unit 34 includes an auxiliary hydraulic pump 34 c that adjusts the output of the hydraulic motor 22 in addition to the hydraulic pumps 34 a and 34 b described above. The auxiliary hydraulic pump 34c can supply hydraulic oil to a swash plate drive mechanism for adjusting the angles of the movable swash plates of the hydraulic motors 22L and 22R. However, an electromagnetic valve 94 for switching between supply / cutoff of hydraulic oil is disposed between the drive mechanism and the hydraulic motors 22L and 22R.

  The electromagnetic valve 94 is electrically connected to the traveling speed stage changeover switch 55. When the operator operates the travel speed stage changeover switch 55 to turn it on, the solenoid valve 94 opens, and when it turns off, the solenoid valve 94 closes.

  When the traveling speed stage changeover switch 55 is OFF, the solenoid valve 94 is closed, so that the hydraulic oil from the auxiliary hydraulic pump 34c is not sent to the swash plate drive mechanism. In this case, the inclination angle of the movable swash plate in the hydraulic motor 22 is increased, and the hydraulic motor 22 is driven at a speed corresponding to the first speed.

  When the travel speed stage changeover switch 55 is turned on, the electromagnetic valve 94 is opened, so that the hydraulic oil from the auxiliary hydraulic pump 34c is sent to the swash plate drive mechanism. Thereby, the inclination angle of the movable swash plate in the hydraulic motor 22 is reduced, and the hydraulic motor 22 is driven at a speed corresponding to the second speed.

  Next, the traveling speed stage changeover switch 55 of the turning work vehicle 1 of the present embodiment will be described in detail. FIG. 4 is a partially enlarged view showing the configuration of the traveling speed stage changeover switch 55.

  As shown in FIGS. 2 and 4, the travel speed stage changeover switch 55 is disposed on the left side of the travel lever 54 </ b> L in the width direction of the control box 52 (the left-right direction of the vehicle body). That is, the traveling levers 54L and 54R and the traveling speed stage changeover switch 55 are disposed at positions shifted from each other in the left-right width direction of the control box 52. Thus, the operator can operate the travel speed stage changeover switch 55 with the left hand while operating the travel levers 54L, 54R with the right hand. The traveling speed stage changeover switch 55 may be arranged on the right side of the traveling lever 54R.

  The travel speed stage changeover switch 55 is disposed on the left side of the upper surface of the control box 52 and slightly near the center. As a result, the traveling speed stage changeover switch 55 can be easily operated with either the left or right hand of the operator.

  As shown in FIG. 4, on the upper surface (front surface) of the traveling speed stage changeover switch 55, an ON mark is displayed on the rear side, and an OFF mark is displayed on the front side. Thus, the operator can easily confirm which one should be pressed to switch the traveling speed stage changeover switch 55 to the ON state / OFF state.

  Further, as shown in FIG. 4, a light transmission portion 57 is provided on the surface of the travel speed stage changeover switch 55 on the side corresponding to the ON state. A lamp (display device) 58 is provided inside the traveling speed stage changeover switch 55 at a position corresponding to the light transmitting portion 57. For example, the lamp 58 can be configured to light up when the traveling speed stage changeover switch 55 is turned on. Thereby, the operator can easily confirm the ON / OFF state of the traveling speed stage changeover switch 55 even in a dark environment (for example, at night).

  On the upper surface of the travel speed stage changeover switch 55, a small picture (icon) indicating the high speed is drawn at the position of the light transmitting portion 57. As a result, the correspondence between the attitude of the traveling speed stage changeover switch 55 and the traveling speed stage can be easily shown to the operator. Further, since the icon is raised by the light when the lamp 58 is lit, the operator can more easily check the ON / OFF state of the traveling speed stage changeover switch 55.

  Thus, in this embodiment, since the speed stage is switched by the travel speed stage switch 55, it is not necessary to assign the speed stage switching operation to the power take-out pedal 56. Accordingly, when the attachment work machine using the double-acting hydraulic actuator is mounted on the turning work vehicle 1 by the combination of the traveling speed stage changeover switch 55 and the power take-out pedal 56, the power take-out pedal 56 is stepped forward. If the attachment work machine is driven on one side and is stepped on the other side, a simple operation driven on the other side can be realized.

  As described above, the turning work vehicle 1 of the present embodiment includes the work operation levers 53L and 53R, the control box 52, and the traveling speed stage changeover switch 55. The work operation levers 53L and 53R are arranged on both the left and right sides of the driver seat 51, respectively. The control box 52 is provided on the floor surface in front of the driver seat 51 so as to protrude upward. The travel speed stage changeover switch 55 is operated by the operator to switch the travel speed stage. The travel speed stage changeover switch 55 is provided in the upper part of the control box 52.

  Thus, by providing the travel speed stage changeover switch 55 at a position where the operator sitting on the driver's seat 51 can visually recognize, the operator can easily confirm the operation state of the high speed stage / low speed stage. Further, by arranging the travel speed stage switch 55 in the control box 52 in front of the driver seat 51, the operator can switch the travel speed stage with either the left or right hand, improving the degree of freedom of operation. be able to.

  In the turning work vehicle 1 of the present embodiment, the control box 52 is provided with a lamp 58 that displays the operating state of the travel speed stage changeover switch 55.

  Thereby, the visibility of the switching state of the traveling speed stage can be further improved.

  Further, the turning work vehicle 1 of the present embodiment includes travel levers 54L and 54R disposed in the control box 52. The traveling speed stage changeover switch 55 is disposed at a position shifted from the traveling levers 54L, 54R in the left-right direction of the control box 52.

  Thus, the operator can operate the traveling speed stage changeover switch 55 with the opposite hand while operating the traveling levers 54L and 54R with one hand. That is, the convenience of two-handed operation can be improved.

  Further, the turning work vehicle 1 of the present embodiment includes a first port 81 and a second port 82 for driving the attachment work machine, and a power take-out pedal 56. The power take-out pedal 56 is used by an operator to operate the attachment work machine with his / her foot. When the power take-out pedal 56 is operated from the neutral position to one side, the hydraulic oil is supplied to the first port 81, and when operated to the opposite side, the hydraulic oil is supplied to the second port 82.

  Thereby, for example, when the attachment work machine includes a double-action attachment cylinder 90, the attachment cylinder 90 can be operated by stepping the power take-out pedal 56 to one side / the other side. Therefore, an intuitive and easy-to-understand operational feeling can be realized.

  The preferred embodiment of the present invention has been described above, but the above configuration can be modified as follows, for example.

  The traveling speed stage changeover switch 55 may be arranged so as to be lined up in the left-right direction with respect to the traveling levers 54L, 54R. Further, the traveling speed stage changeover switch 55 may be disposed on the upper rear surface.

  The traveling speed stage changeover switch 55 may be configured as another type of electric switch instead of the rocker switch.

  For example, the ramp 58 may be disposed in the vicinity of the travel speed stage changeover switch 55 on the upper surface of the control box 52 instead of the configuration built in the travel speed stage changeover switch 55.

  The position of each operation member can be changed as appropriate. For example, the power take-out pedal 56 may be disposed on the right side of the control box 52.

  The present invention can be applied not only to a turning work vehicle but also to work vehicles having various other configurations and uses.

1 Work vehicle 51 Driver's seat 52 Control box 53L, 53R Work control lever (control lever)
55 Travel Speed Stage Switch (Travel Speed Stage Switching Device)
56 Pedal for power take-off 58 Lamp (display device)
81 1st port 82 2nd port

Claims (4)

An operation lever arranged on each of the left and right sides of the driver seat;
A control box provided to protrude upward on the floor surface in front of the driver seat;
A traveling speed stage switching device operated by an operator for switching the traveling speed stage;
With
The work speed stage switching device is provided at an upper part of the control box. The work vehicle according to claim 1,
A work vehicle, wherein a display device for displaying an operation state of the traveling speed stage switching device is disposed in the control box. The work vehicle according to claim 1 or 2,
A travel lever disposed in the control box;
The work speed stage switching device is arranged at a position shifted from the travel lever in the left-right direction of the control box. A work vehicle according to any one of claims 1 to 3,
A first port and a second port for driving the attachment work machine;
A foot pedal for an operator to operate the attachment work machine with a foot;
With
When the foot pedal is operated from the neutral position to one side, the working oil is supplied to the first port, and when operated to the opposite side, the working oil is supplied to the second port.

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