Work vehicle

Abstract

To provide a work vehicle capable of releasing braking of a drive wheel by removing a malfunctioning electric brake.SOLUTION: A work vehicle comprises: a brake device (52) which brakes rotation of a front wheel (2); an electric brake (80) which is installed in an electric room (8) located at the rear lower side of an operation section (5) and activates and deactivates the brake device (52); a brake switch (15) which is installed in the operation section (5) and operates to activate and deactivate the electric brake (80). The electric brake (80) is engaged with a support frame (84), which is installed in the electric room (8) and extended in a front-rear direction, through a support member (83) upwardly extended from an upper section of the electric brake (80). When the electric brake (80) malfunctions, the brake device (52) can be deactivated by releasing the engagement between the electric brake (80) and the support frame (84).SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to a work vehicle for mowing turf grass.

Background Art

[0002] Conventionally, there is known a vehicle equipped with a technique of providing a brake operated by an operator himself / herself and an electric brake operated via an electric signal to brake drive wheels. (Patent Document 1)

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the means of Patent Document 1, there is a problem that the electric brake malfunctions due to a short circuit such as a disconnection of a signal line, and the braking of the drive wheels cannot be released.

[0005] Therefore, an object of the present invention is to provide a work vehicle capable of releasing the braking of drive wheels without removing a malfunctioning electric brake.

Means for Solving the Problems

[0006] The present invention that has solved the above problems is as follows. That is, in the invention according to claim 1, in a work vehicle provided with a pair of left and right front wheels (2) and rear wheels (3) on the lower side of a body frame (1), a work device (4) for mowing turf grass on the front side of the body frame (1), and an operator's cab (5) on the upper side of the body frame (1), A braking device (52) for braking the rotation of the front wheels (2) is provided, an electric brake (80) for operating and releasing the operation of the braking device (52) is provided in an electric chamber (8) below the rear side of the control unit (5), a brake switch (15) for operating and releasing the operation of the electric brake (80) is provided on the control unit (5), the electric brake (80) is engaged with a support frame (84) extending in the front-rear direction provided in the electric chamber (8) via a support member (83) extending upward from the upper part of the electric brake (80), and when the electric brake (80) malfunctions, the engagement between the electric brake (80) and the support frame (84) is released to release the operation of the braking device (52). The work vehicle is characterized by this configuration.

[0007] The invention according to claim 2 is a work vehicle according to claim 1, wherein a brake pedal (11) operated by an operator's foot and a brake lever (14) operated by an operator's arm for operating and releasing the operation of the braking device (52) are provided on the control unit (5), and when the brake pedal (11) or the brake lever (14) is operated, the engagement between the electric brake (80) and the support frame (84) can be released, and when the brake pedal (11) and the brake lever (14) are not operated, the release of the engagement between the electric brake (80) and the support frame (84) is restricted.

[0008] The invention according to claim 3 is a work vehicle according to claim 2, wherein the arm (52A) of the braking device (52) is connected to a rotating shaft (50) via a rod (51), and in a view of the axis of the rotating shaft (50), the rotation angle of the rotating shaft (50) when the brake pedal (11) and the brake lever (14) are operated is set to be larger than the rotation angle of the rotating shaft (50) when the electric brake (80) is operated.

[0009] The invention according to claim 4 forms the engagement between the electric brake (80) and the support frame (84) by inserting a pin (86) extending rightward from the handle (87) through the first opening (83B) of the support member (83) and the second opening (84B) of the support frame (84), and provides a biasing component (88) for biasing the pin (86) rightward between the handle (87) and the protrusion (86A) of the pin (86). It is a work vehicle according to claim 3.

[0010] The invention according to claim 5 inserts the upper part of the support member (83) through the third opening (84A) of the support frame (84), and provides an engagement member (83A) longer than the major axis of the third opening (84A) at the upper end of the support member (83). It is a work vehicle according to claim 4.

Advantages of the Invention

[0011] According to the invention described in claim 1, a brake device (52) for braking the rotation of the front wheels (2) is provided, an electric brake (80) for operating and releasing the operation of the brake device (52) is provided in an electric chamber (8) on the lower rear side of the control section (5), a brake switch (15) for operating and releasing the operation of the electric brake (80) is provided on the control section (5), and the electric brake (80) is engaged with a support frame (84) extending in the front-rear direction provided in the electric chamber (8) via a support member (83) extending upward from the upper part of the electric brake (80). When the electric brake (80) malfunctions, the engagement between the electric brake (80) and the support frame (84) is released to release the operation of the brake device (52). Therefore, the malfunctioning electric brake (80) can be removed and the operation of the brake device (52) for braking the rotation of the front wheels (2) can be released.

[0012] According to the invention described in claim 2, in addition to the effects of the invention described in claim 1, the control unit (5) is provided with a brake pedal (11) that an operator operates with the foot to actuate and release the brake device (52), and a brake lever (14) that the operator operates with the arm. When the brake pedal (11) or the brake lever (14) is operated, the engagement between the electric brake (80) and the support frame (84) can be released. When the brake pedal (11) and the brake lever (14) are not operated, the release of the engagement between the electric brake (80) and the support frame (84) is restricted. Therefore, the electric brake (80) can be safely removed while the brake device (52) is actuated to brake the rotation of the front wheels (2).

[0013] According to the invention described in claim 3, in addition to the effects of the invention described in claim 2, the arm (52A) of the brake device (52) is connected to the rotating shaft (50) via a rod (51). In the axial view of the rotating shaft (50), the rotation angle of the rotating shaft (50) when the brake pedal (11) and the brake lever (14) are operated is set to be larger than the rotation angle of the rotating shaft (50) when the electric brake (80) is actuated. Therefore, the malfunctioning electric brake (80) can be easily removed.

[0014] According to the invention described in claim 4, in addition to the effects of the invention described in claim 4, the engagement between the electric brake (80) and the support frame (84) is formed by inserting a pin (86) extending rightward from the handle (87) into the first opening (83B) of the support member (83) and the second opening (84B) of the support frame (84). An urging component (88) for urging the pin (86) rightward is provided between the handle (87) and the protrusion (86A) of the pin (86). Therefore, the electric brake (80) can be easily removed from the support frame (84). Also, it is possible to prevent the pin (86) from coming out of the first opening (83B) and the second opening (84B) due to vibrations during traveling or the like.

[0015] According to the invention described in claim 5, in addition to the effects of the invention described in claim 4, the upper part of the support member (83) is inserted into the third opening (84A) of the support frame (84), and an engaging member (83A) longer than the major axis of the third opening (84A) is provided at the upper end of the support member (83). Therefore, it is possible to prevent the electric brake (80) from falling excessively and colliding with other components.

Brief Description of the Drawings

[0016]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

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Figure 11

Embodiments for Carrying Out the Invention

[0017] As shown in FIG. 1, in the work vehicle, a pair of left and right front wheels 2 are provided at the front part below the body frame 1, and a pair of left and right rear wheels 3 are provided at the rear part below the body frame 1.

[0018] At the front of the body frame 1, a working device 4 for mowing the turf growing in the field is provided. At the rear side of the working device 4, a control section 5 for the operator to board is provided. At the rear side of the control section 5, a safety frame (ROPS) 6 for protecting the operator is provided. At the rear side of the safety frame 6, a grass collecting container 7 for storing the mowed turf is provided. Below the grass collecting container 7, an electric motor room 8 for arranging an electric motor 30, a battery 33, etc. to be described later for driving the working device 4 is provided.

[0019] In front of the driver's seat of the control section 5, a steering column 10 for supporting the steering wheel is provided. At the upper part of the steering column 10, a monitor for displaying the output rotation speed etc. of the electric motor 30 is provided, and the lower part is fixed to the front part of the floor.

[0020] On the left side of the steering column 10 on the floor, a brake pedal 11 for braking the rotation of the front wheel 2 is provided, and on the right side, an accelerator pedal 12 for increasing or decreasing the rotation speed of the front wheel 2 is provided.

[0021] Above the front wheel 2 is covered with a fender 13. On the fender 13 located on the left side of the driver's seat, a brake lever 14 for braking the rotation of the front wheel 2 is provided, and on the fender 13 located on the right side of the driver's seat, a brake switch 15 for operating an electric brake 80 to be described later is provided.

[0022] The rear part of the working device 4 and the front part of the grass collecting container 7 are communicated by a shooter 16 extending in the front-rear direction. In the middle part of the shooter 16 in the front-rear direction, a blower for exhausting air into the shooter 16 is provided.

[0023] At the front parts of the left and right walls of the grass collecting container 7, a pair of left and right link arms 18 are provided. The front parts of the link arms 18 are swingably fixed to the left and right parts of the safety frame 6, and the safety frame 6 and the link arms 18 are connected by a lifting and lowering component 19 such as a hydraulic cylinder. Also, the rear part of the lower wall of the grass collecting container 7 is placed on the horizontal frame 21A of a support frame 21 to be described later. Thereby, the grass collecting container 7 can be lifted and lowered by driving the lifting and lowering component 19.

[0024] As shown in FIGS. 2 and 3, in the front electric chamber 8A of the electric chamber 8, a working motor 30 for driving the working device 4 and a traveling motor 31 for rotating the front wheels 2 are provided, and in the rear electric chamber 8B, a battery 33 for storing the electric power supplied to the motor 30 and the like is provided.

[0025] In plan view, the motor 30 is provided on the left side of the center line in the left-right direction of the machine body frame 1, and the motor 31 is provided on the right side of the center line in the left-right direction of the machine body frame 1. Thereby, it is possible to suppress the weight difference between the weight applied to the left side of the center line in the left-right direction of the machine body frame 1 and the weight applied to the right side of the center line in the left-right direction of the machine body frame 1, and improve the steerability.

[0026] In side view, a support frame 20 extending upward from the machine body frame 1 is provided at the partition portion between the front electric chamber 8A and the rear electric chamber 8B, and a support frame 21 extending upward from the machine body frame 1 is provided at the rear end portion of the rear electric chamber 8B.

[0027] The support frame 20 is formed by a left vertical frame 20L extending upward from the intermediate portion on the left side of the machine body frame 1, a right vertical frame 20R extending upward from the intermediate portion on the right side of the machine body frame 1, and a horizontal frame 20A extending in the left-right direction connecting the upper portions of the left vertical frame 20L and the right vertical frame 20R.

[0028] The support frame 21 is formed by a left vertical frame 21L extending upward from the rear end portion on the left side of the machine body frame 1, a right vertical frame 21R extending upward from the rear end portion on the right side of the machine body frame 1, a horizontal frame 21A extending in the left-right direction connecting the upper portions of the left vertical frame 21L and the right vertical frame 21R, and a horizontal frame 21B extending in the left-right direction connecting the intermediate portions of the left vertical frame 21L and the right vertical frame 21R. Note that the left portion of the horizontal frame 21B extends to the left side of the left vertical frame 21L, and the right portion extends to the right side of the right vertical frame 21R.

[0029] The middle part of the left vertical frame 20L and the left end part of the horizontal frame 21B are connected by a left front-rear frame 22L extending in the front-rear direction, and the middle part of the right vertical frame 20R and the right end part of the horizontal frame 21B are connected by a right front-rear frame 22R extending in the front-rear direction. Thereby, the rear part of the battery 33 can be arranged above the drive shaft 46 of the rear wheel 3, and large deformation of the body frame 1 can be prevented.

[0030] The upper part of the left vertical frame 20L and the middle part of the left vertical frame 23 provided at the rear part of the control part 5 are connected by a left front-rear frame 24 extending in the front-rear direction, and the upper part of the right vertical frame 20R of the support frame 20 and the middle part of the right vertical frame 23 provided at the rear part of the control part 5 are connected by a right front-rear frame 24 extending in the front-rear direction.

[0031] As shown in FIG. 4, the longitudinal direction of the electric motor 30 is provided along the front-rear direction. The electric motor 31 is provided adjacent to the left side of the electric motor 30, and the longitudinal direction of the electric motor 31 is provided along the front-rear direction.

[0032] A radiator 40 for cooling the water that cools the electric motor 30 etc. is provided outside the left wall of the electric motor chamber 8, and a fan 41 for blowing outside air toward the electric motor chamber 8 is provided between the radiator 40 and the electric motor 30. A circular opening (not shown) is formed at a portion of the left wall of the electric motor chamber 8 facing the fan 41. Thereby, the temperature rise of the electric motor 30 etc. can be suppressed, and it can be prevented that the electric motor 30 etc. malfunction.

[0033] An auxiliary battery 42 for storing the electric power supplied to the monitor of the control part 5 is provided outside a portion of the right wall of the electric motor chamber 8 facing the radiator 40. Thereby, the weight difference between the left part and the right part of the work vehicle can be suppressed.

[0034] As shown in FIGS. 3 and 5, the front portion of the mounting frame 34 that fixes the upper part of the battery 33 is detachably fixed to the horizontal frame 20A of the support frame 20 by a fastening member such as a bolt, and the rear portion is detachably fixed to the horizontal frame 21A of the support frame 21 by a fastening member such as a bolt.

[0035] The left mounting frame 35 that fixes the lower part of the battery 33 is placed on the left front-rear frame 22L, and the right mounting frame 35 is placed on the right front-rear frame 22R.

[0036] Openings 34A for inserting a suspension hook are formed at the front and rear portions of the mounting frame 34 when the battery 33 is replaced. Thereby, the battery 33 can be easily attached to and detached from the support frame 20 and the support frame 21, and the battery 33 can be easily replaced.

[0037] <Brake System> As shown in FIGS. 6 to 8, the brake system 100 that brakes the rotation of the front wheel 2 includes a brake pedal 11, a brake lever 14, an electric brake 80 operated by a brake switch 15, a rotating shaft 50 extending in the left-right direction that is rotated by stepping on the brake pedal 11 or the like, and a brake device 52 operated by the rotation of the rotating shaft 50.

[0038] The tip of the arm 50A provided at the left part of the rotating shaft 50 and the tip of the arm 52A that moves the brake pad provided at the lower part of the brake device 52 are connected via a rod 51 extending in the vertical direction. Thereby, the rotation of the front wheel 2 can be braked by rotating the rotating shaft 50 to move the brake pad of the brake device 52.

[0039] The base of the brake pedal 11 is swingably supported by a support shaft 60 extending in the left-right direction. The rear part of the base of the brake pedal 11 is connected to the tip of the arm 50B provided at the left part of the rotating shaft 50 via a link 61 extending rearward and downward and a link 62 extending in the front-rear direction.

[0040] The rear part of link 61 and the front part of link 62 are rotatably fixed to a pin 64 extending in the left - right direction at the tip of an arm 63A provided on a rotating shaft 63 extending in the left - right direction. Thus, when the brake pedal 11 is depressed, in the axial view of the rotating shaft 50, the rotating shaft 50 rotates clockwise, moves the rod 51 upward, and the braking device 52 operates to brake the rotation of the front wheel 2. Also, when the depression of the brake pedal 11 is released, in the axial view of the rotating shaft 50, the rotating shaft 50 rotates counterclockwise, the rod 51 moves downward, and the operation of the braking device 52 stops.

[0041] The base of the brake lever 14 is swingably supported by a support shaft 70 extending in the left - right direction. The lower part of the base of the brake lever 14 is connected to the tip of an arm 50B provided on the left part of the rotating shaft 50 via a link 71 extending in the up - down direction and a link 72 extending in the front - rear direction.

[0042] An opening 71A having a long axis in the up - down direction is formed in the lower part of the link 71, and a pin 74 extending in the left - right direction at the front part of an arm 73A provided on the left part of the rotating shaft 73 is locked to be movable in the up - down direction in the opening 71A.

[0043] The front part of the link 72 is rotatably fixed to a pin 75 extending in the left - right direction at the lower part of an arm 73B provided on the right part of the rotating shaft 73. Thus, when the brake lever 14 is pulled up, in the axial view of the rotating shaft 50, the rotating shaft 50 rotates clockwise, moves the rod 51 upward, and the braking device 52 operates to brake the rotation of the front wheel 2. Also, when the pulling - up of the brake lever 14 is released, in the axial view of the rotating shaft 50, the rotating shaft 50 rotates counterclockwise, the rod 51 moves downward, and the operation of the braking device 52 stops.

[0044] When the brake switch 15 of the control unit 5 is pressed, the rod 80A of the electric brake 80 moving in the up - down direction rises, and when the pressing of the brake switch 15 is released, the rod 80A of the electric brake 80 descends.

[0045] The lower part of the rod 80A is connected to the tip of the arm 50C provided between the arms 50A and 50B of the rotating shaft 50 via a link 81 extending in the vertical direction. Thus, when the brake switch 15 is pressed, in the axial view of the rotating shaft 50, the rotating shaft 50 rotates clockwise, moves the rod 51 upward, and the braking device 52 can be actuated to brake the rotation of the front wheel 2. Also, when the pressing of the brake switch 15 is released, in the axial view of the rotating shaft 50, the rotating shaft 50 rotates counterclockwise, the rod 51 moves downward, and the operation of the braking device 52 stops.

[0046] As shown in FIGS. 9 and 10, the upper part of the electric brake 80 is fixed to a support frame 84 made of channel steel extending in the front-rear direction provided in the front electric chamber 8A via a plate-shaped support member 83 extending in the vertical direction. Note that the lower part of the rod 80A of the electric brake 80 and the upper part of the link 81 are detachably fixed by a pin 82, and the upper part of the electric brake 80 and the support member 83 are detachably fixed by a pin 82B. Thus, when the electric brake 80 fails, the pins 82A and 82B can be pulled out to easily replace the electric brake 80.

[0047] The support member 83 is provided by inserting an opening (the "third opening" in the claims) 84A having a major axis in the front-rear direction formed in the lower side and the upper side of the support frame 84 from the lower side to the upper side. An engaging member 83A such as a rod extending in the front-rear direction is provided at the upper end of the support member 83. Also, the length of the engaging member 83A in the front-rear direction is formed to be longer than the length of the opening 84A in the front-rear direction. Thus, when the pin 86 described later is pulled out, it is possible to prevent the electric brake 80 from falling excessively and colliding with other components.

[0048] On the left side of the support frame 84, there are provided a circular opening (the "second opening" in the claims) 84B formed on the left side of the support frame 84, a pin 86 extending in the left - right direction and inserted through the circular opening (the "first opening" in the claims) 83B formed in the support member 83, and a handle 87 fixed to the left part of the pin 86. Note that the left part of the pin 86 is fixed to be movable in the left - right direction with respect to the inner peripheral part of the handle 87.

[0049] A protrusion 86A formed by a pin extending in the up - down direction is formed at the middle part of the pin 86, and a biasing component 88 such as a spring for pushing the pin 86 from the support frame 84 toward the support member 83 is provided between the right part of the handle 87 and the left part of the protrusion 86A. Thereby, the pin 86 inserted through the opening 83B and the opening 84B is prevented from being pulled out from the opening 83B and the opening 84B due to vibrations during running, and the electric brake 80 can be suspended at a predetermined position.

[0050] The clockwise rotation angle of the rotary shaft 50 when the brake pedal 11 is depressed and the clockwise rotation angle of the rotary shaft 50 when the brake lever 14 is pulled up are formed to be larger than the clockwise rotation angle of the rotary shaft 50 when the brake switch 15 is depressed to drive the electric brake 80 and the rod 80A is moved upward. Thereby, when the electric brake 80 malfunctions and the rod 80A cannot move downward from above and the braking of the brake device 52 cannot be released, the brake pedal 11 can be depressed or the brake lever 14 can be pulled up to reduce the external force acting on the engaging part of the pin 86 with the opening 83B or the opening 84B, and the pin 86 can be pulled out from the opening 83B and the opening 84B.

[0051] As shown in FIG. 11, it is preferable that the brake device 52, the rod 51, etc. can be visually observed through the gap between the safety frame 6 and the electric chamber 8. Thereby, it can be easily confirmed that the electric brake 80 has malfunctioned.

[0052] On one side of the rotating shaft 50, a rotation sensor for measuring the rotation angle of the rotating shaft 50 is provided, and on the electric brake 80, a stroke sensor for measuring the vertical movement of the rod 80A is provided. When the measured value of the rotation sensor does not change when the brake pedal 11 is depressed or released, or when the measured value of the stroke sensor does not change when the brake switch 15 is pressed or released, a warning display is made on the monitor of the control unit 5. Thereby, the operator can be promptly notified of a malfunction in the electric brake 80 or the like.

Explanation of Signs

[0053] 1 Body frame 2 Front wheel 3 Rear wheel 4 Working device 5 Control unit 8 Electric room 11 Brake pedal 14 Brake lever 15 Brake switch 50 Rotating shaft 51 Rod 52 Brake device 52A Arm 80 Electric brake 83 Support member 83A Engaging member 83B Opening (first opening) 84 Support frame 84A Opening (third opening) 84B Opening (second opening) 86 Pin 86A Protrusion 87 Handle 88 Biasing component

Claims

1. A working vehicle is provided with a pair of left and right front wheels (2) and rear wheels (3) on the lower side of a body frame (1), a working device (4) for mowing turf is provided on the front side of the body frame (1), and an operator's cab (5) for the operator to board is provided on the upper side of the body frame (1). In this working vehicle, a braking device (52) for braking the rotation of the front wheels (2) is provided, an electric brake (80) for operating and releasing the operation of the braking device (52) is provided in an electric chamber (8) on the lower rear side of the cab (5), a brake switch (15) for operating and releasing the operation of the electric brake (80) is provided on the cab (5), the electric brake (80) is engaged with a support frame (84) extending in the front-rear direction provided in the electric chamber (8) via a support member (83) extending upward from the upper part of the electric brake (80), when the electric brake (80) malfunctions, the engagement between the electric brake (80) and the support frame (84) is released to release the operation of the braking device (52). The working vehicle is characterized by this configuration.

2. a brake pedal (11) operated by the operator's foot and a brake lever (14) operated by the operator's arm for operating and releasing the operation of the braking device (52) are provided on the cab (5), when the brake pedal (11) or the brake lever (14) is operated, the engagement between the electric brake (80) and the support frame (84) can be released, when the brake pedal (11) and the brake lever (14) are not operated, the release of the engagement between the electric brake (80) and the support frame (84) is restricted. The working vehicle according to Claim 1.

3. an arm (52A) of the braking device (52) is connected to a rotating shaft (50) via a rod (51), in a view of the axis of the rotating shaft (50), the rotation angle of the rotating shaft (50) when the brake pedal (11) and the brake lever (14) are operated is set larger than the rotation angle of the rotating shaft (50) when the electric brake (80) is operated. The working vehicle according to Claim 2.

4. the engagement between the electric brake (80) and the support frame (84) is formed by inserting a pin (86) extending rightward from a handle (87) through a first opening (83B) of the support member (83) and a second opening (84B) of the support frame (84). The work vehicle according to claim 3, wherein a biasing member (88) for biasing the pin (86) in the right direction is provided between the handle (87) and the protruding portion (86A) of the pin (86).

5. The work vehicle according to claim 4, wherein an upper portion of the support member (83) is inserted into a third opening (84A) of a support frame (84), and an engaging member (83A) longer than the major axis of the third opening (84A) is provided at an upper end portion of the support member (83).

Images