Work vehicles

Abstract

To provide a work vehicle including a seat which enables safe driving.SOLUTION: A work vehicle includes: a seat bracket (101) which supports a seat (20) in a manner that the seat (20) can rotate around a rotary shaft (114) at one end as seen in an anteroposterior direction of the seat (20) in the anteroposterior direction; and a rotation restriction tool (106) which detachably attaches the other end as seen in the anteroposterior direction of the seat (20) and the other end as seen in the anteroposterior direction of the seat bracket (101) to each other and which restricts rotation of the seat (20) in a state that the other end of the seat (20) and the other end of the seat bracket (101) are attached. The structure prevents the seat (20) from being rotated unexpectedly during traveling to allow safe driving.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a work vehicle such as a tractor, a seedling transplanter, or a lawnmower. [Background technology]

[0002] Among work vehicles such as tractors, seedling transplanters, and lawn mowers that do not have a cabin surrounding the driver's cab, there are known ones in which the seat rotates around the front end of the seat so that the seat surface faces downward (the seat is in an upside-down position) to prevent the seat from becoming wet with rainwater or from accumulating dust during periods of non-use, such as when work is suspended or the vehicle is stored in a garage. Among such work vehicles with rotatable seats, there is known a work vehicle equipped with a seating sensor that detects whether the driver is seated (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-82715 Summary of the Invention [Problem to be solved by the invention]

[0004] In the conventional technology described in Patent Document 1, the seat is rotatable, so when the driver is seated and working and making an emergency stop or going over a bank, the driver's seat may rotate unintentionally, causing the driver to be pushed out or fall over.

[0005] A technical object of the present invention is to provide a work vehicle equipped with a seat that allows safe operation. [Means for solving the problem]

[0006] The above-mentioned problems of the present invention are solved by the following means. The invention described in claim 1 includes a traveling vehicle body (1), a seat (20) on which a driver who drives the traveling vehicle body (1) can sit, a seat bracket (101) disposed on the traveling vehicle body (1) and supporting the seat (20) rotatably in the front-rear direction around a rotation axis (114) at one end of the seat (20) in the front-rear direction, and a rotation restricting device (106) detachably attachable to the other end of the seat (20) in the front-rear direction and the other end of the seat bracket (101) in the front-rear direction, the rotation restricting device (106) restricting the rotation of the seat (20) when the other end of the seat (20) and the other end of the seat bracket (101) are attached; a seat spring (104) that applies a force to the seat (20) in a direction in which the seat (20) moves away from the seat bracket (101); and a seat support part (103) that comes into contact with a lower part of the seat (20) to support the seat (20) when the driver sits down and the seat spring (104) is compressed. a seating sensor (109) that detects a first position where the seat (20) is pushed up by the seat spring (104) and a second position where the seat support part (103) supports a lower part of the seat (20) and thereby detects whether the driver is sitting or leaving the seat; the seating sensor (109) that detects a third position where the seat (20) is rotated from the first position in a direction away from the seat bracket (101); and a control part (C) that stops the engine (12) when the seating sensor (109) continuously detects a position between the first position and the second position for a predetermined period while the engine (12) is operating, and that immediately stops the engine (12) when the seating sensor (109) detects the third position while the engine (12) is operating. The work vehicle is characterized by being equipped with:

[0007] Claim 2 The invention described in (1) is characterized in that the first position is a state in which the driver leaves the seat, the seat (20) is pushed in the rotational direction by the force of the seat spring (104), and the rotation is restricted by the rotation restricting device (106), so that the lower part of the seat (20) is separated from the seat support part (103). Claim 1 It is a work vehicle described in [Effects of the Invention]

[0008] According to the invention of claim 1, by restricting the rotation of the seat (20) with the rotation restricting device (106), it is possible to prevent the seat (20) from rotating unexpectedly while traveling, and it is possible to provide a work vehicle equipped with a seat that can be driven safely. According to the invention described in claim 1, By using the seating sensor (109), it is possible to reliably detect whether the driver is seated. Furthermore, according to the invention described in claim 1, it is possible to detect whether or not a person is seated at the first position and the second position, and it is also possible to detect whether or not the seat (20) is in an unsuitable state for sitting at the third position. Furthermore, according to the invention as set forth in claim 1, it is possible to prevent the vehicle from traveling in a state where no one is seated for a long time or where the seat (20) is unsuitable for sitting, thereby improving safety. Claim 2 According to the described invention, Claim 1 In addition to the effects of the invention described above, it is possible to prevent the seat from rotating further than the first position, which is an unsuitable position for sitting, and to drive safely. 。 [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a side view of a riding rice transplanter according to an embodiment. [Figure 2] FIG. 2 is a plan view of the riding rice transplanter according to the embodiment. [Figure 3] FIG. 3 is an explanatory diagram of a seat according to an embodiment. [Figure 4] FIG. 4 is an explanatory diagram of the seat bracket according to the embodiment. [Figure 5] FIG. 5 is a view of the seat according to the embodiment as seen from diagonally below. [Figure 6] 6A and 6B are explanatory diagrams of the rotation restricting device according to the embodiment, with FIG. 6A being an explanatory diagram of a state where it has been moved to the rotation restricting position, and FIG. 6B being an explanatory diagram of a state where it has been moved to the rotatable position. [Figure 7] Figure 7 is an explanatory diagram of the state of the seat in the embodiment, where Figure 7(A) is an explanatory diagram of the seating position, Figure 7(B) is an explanatory diagram of the state of the seat spring in the seating position, Figure 7(C) is an explanatory diagram of the leaving position, Figure 7(D) is an explanatory diagram of the state of the seat spring in the leaving position, Figure 7(E) is an explanatory diagram of the state when the rotation restricting device is separated from the rotation restricted part, Figure 7(F) is an explanatory diagram of the state of the seat spring in the state of Figure 7(E), and Figure 7(G) is an explanatory diagram of the state when the seat is rotated forward. [Figure 8] FIG. 8 is an explanatory diagram of the armrest portion of the embodiment. [Figure 9] FIG. 9 is an explanatory view of the cover member of the armrest in FIG. [Figure 10] FIG. 10 is an explanatory diagram of a groove for a main speed change lever provided in the armrest of FIG. [Figure 11] FIG. 11 is a side view of the main speed change lever portion of the armrest shown in FIG. [Figure 12] FIG. 12 is an explanatory diagram of the main parts of the main shift lever, with FIG. 12(A) being a view from diagonally rear, FIG. 12(B) being a view from diagonally front, and FIG. 12(C) being a view from the side. DETAILED DESCRIPTION OF THE INVENTION

[0010] An embodiment of the present invention will be described below. A four-row planting riding rice transplanter, which is an example of a work vehicle according to the present invention and is one embodiment of a seedling transplanter, will be described in detail with reference to the drawings. FIG. 1 is a side view of a riding rice transplanter according to an embodiment. FIG. 2 is a plan view of the riding rice transplanter according to the embodiment. As shown in the side view of Figure 1 and the plan view of Figure 2, the riding rice transplanter is configured to function as a riding fertilizer rice transplanter by attaching a seedling planting device 3, which is a type of work machine, to a traveling vehicle (traveling body) 1 via a lifting link device 2 and also by providing a fertilizer applicator 4. The traveling vehicle 1 is a four-wheel drive vehicle with a pair of front wheels 6, 6 and a pair of rear wheels 7, 7, which are drive wheels. In this specification, the left and right sides of the forward movement direction of the rice transplanter are referred to as the left and right sides, respectively, and the forward movement direction is referred to as the front side and the backward movement direction is referred to as the rear side.

[0011] As shown in FIG. 1, a transmission case 11 and an engine (internal combustion engine) 12 are arranged on main frames 10a and 10b, a hydraulic pump 13 is integrally assembled with the transmission case 11 on the rear side of the transmission case 11, and a steering post 14 protrudes from the front upper part of the transmission case 11. A steering handle 16 is attached to the upper end of the steering post 14. A step floor 19, which serves as a floor for operation, is attached to the top of the aircraft, and a seat 20 is installed above the engine 12. A gear shift control lever (travel control member, HST lever) 17 is provided to the right of the steering handle 16.

[0012] In front of the seat 20, an operation panel (not shown) is provided on the steering post 14. A clutch lever 18 is provided on the right side of the seat 20. The front wheels 6, 6 are journaled on front wheel support cases 22, 22 that are mounted on the sides of the transmission case 11 so that their orientation can be changed. The rear wheels 7, 7 are journaled via rear wheel supports 30 on rear wheel transmission cases 24, 24 attached to both left and right ends of left and right frames 37. The left and right frames 37 are supported on the rear ends of the main frames 10a, 10b.

[0013] As shown in Figures 1 and 2, which show part of the power transmission mechanism to the rear wheels 7, the rotational power of the engine 12 is transmitted to the input shaft 32a of the hydraulic continuously variable transmission (HST) 31 via a pulley 27, a belt 28, and a pulley 29 in that order, and is then transmitted from the output shaft 32b of the HST 31 into the transmission case 11. The rear ends of the rear output shafts 11a, 11b protrude rearward from the transmission case 11, and these protruding ends are connected to left and right rear wheel transmission shafts 35, 35 that transmit power to the rear wheel transmission cases 24, 24. The left and right rear wheels 7, 7 are driven and rotated by the left and right rear wheel transmission shafts 35, 35, respectively.

[0014] The seedling planting device 3 is attached to the traveling vehicle 1 by a lifting link device 2 so that it can be raised and lowered freely. The upper end of the piston of a general lift cylinder 36 (Figure 1), the base of which is rotatably mounted on the traveling vehicle 1, is connected to the lifting link device 2, and pressurized oil is supplied to and discharged from the lift cylinder 36 via a lifting valve (not shown) by a hydraulic pump 13 mounted on the traveling vehicle 1, thereby extending and retracting the piston of the lift cylinder 36, and the seedling planting device 3 connected to the lifting link device 2 is moved up and down.

[0015] The seedling planting device 3 is composed of a planting transmission case 38, which also serves as a frame and is mounted to the rear of the lifting link device 2 via left and right frames 37 in a rolling manner; a seedling carrier (seedling tank) 39 that is supported by supports attached to the planting transmission case 38 and moves back and forth in the left-right direction of the machine body; a seedling planting tool 41 attached to the rear end of the planting transmission case 38 and plants seedlings one by one in the field from the bottom of the seedling carrier 39; and a center float (sensor float) 42 and a side float 43, which are ground leveling bodies whose rear parts are pivotally supported on the bottom of the planting transmission case 38 and whose front parts are attached so that they can swing up and down. The center float 42 and the side floats 43 are provided to level the field and also to level the front of the field where the seedlings will be planted by the seedling planting tool 41.

[0016] The PTO transmission shaft 45 (FIG. 1) has universal joints at both ends and is provided to transmit power from the transmission case 11 to the planting transmission case 38 of the seedling planting device 3. The seedling planting device 3 has a four-row planting configuration and is equipped with a planting transmission case 38 that also serves as a frame, a seedling loading platform 39 that carries seedlings and moves back and forth from side to side to supply seedlings one by one to the seedling outlet 39a of each row (Figure 2), and a seedling planting tool 41 that plants the seedlings supplied to the seedling outlet 39a in the field.

[0017] 1, rotor 70a is disposed in front of center float 42, and rotor 70a is disposed forward of rotor 70b, which is disposed in front of side float 43. Power is transmitted to rotor 70a from a gear in rear wheel transmission case 24 of rear wheel 7 via transmission shaft 25, and power is transmitted to rotor 70b from a pair of chains (not shown) in a pair of left and right chain cases 71, 71 to which power is transmitted from drive shafts (not shown) of both rotors 70a, 70a, respectively.

[0018] The rear wheel transmission case 24 of the rear wheel 7 is attached to both left and right ends of the left and right frames 37 and is journalled on the rear wheel support 30 . Rotation of the rear wheel transmission case 24 causes the axle 23 of the rear wheel 7 to move up and down integrally with the rear wheel transmission case 24. Power is transmitted to the rear wheel transmission case 24 from the transmission case 11 via left and right rear wheel transmission shafts 35.

[0019] The fertilizer application device 4 discharges fertilizer from the fertilizer tank 67 downward in fixed amounts by the fertilizer delivery section 68, and the delivered fertilizer is transported by the blower 69 through the fertilizer application hose 62 to the fertilizer application guide 80, where it is dropped into a fertilizer application furrow formed near the side of the seedling planting row by a furrow making body 82 provided in front of the fertilizer application guide 80. In addition, a pedal 86 (Figure 2) can operate both the main clutch and the left and right rear wheel brake devices (not shown), and is located on the lower right side of the steering handle 16. When this pedal 86 is depressed, the main clutch is disengaged, and then the left and right rear wheel brakes are applied, bringing the aircraft to a stop.

[0020] (Seat description) FIG. 3 is an explanatory diagram of a seat according to an embodiment. FIG. 4 is an explanatory diagram of the seat bracket according to the embodiment. FIG. 5 is a view of the seat according to the embodiment as seen from diagonally below. 3 to 5, in the traveling vehicle 1 of the embodiment, the seat 20 is arranged on top of a seat bracket 101 of the traveling vehicle 1. In Fig. 4, the seat bracket 101 of the embodiment is formed in a plate shape with an opening formed in the center. The seat bracket 101 is provided with a shaft support part 102 at the front end part, which is an example of one end part in the front-rear direction. A pair of left and right seat support parts 103 are arranged at the rear end, which is an example of the other end in the front-rear direction, of the seat bracket 101. A pair of left and right seat springs 104 are arranged inside the seat support parts 103 in the left-right direction. A buffer rubber plate 104a is arranged at the upper end of the seat springs 104.

[0021] 6A and 6B are explanatory diagrams of the rotation restricting device according to the embodiment, with FIG. 6A being an explanatory diagram of a state where it has been moved to the rotation restricting position, and FIG. 6B being an explanatory diagram of a state where it has been moved to the rotatable position. A rotation restricting device 106 is disposed on the inside of the seat spring 104 in the left-right direction. In FIG. 6 , the rotation restricting device 106 of this embodiment has a slide support portion 107 fixed to the seat bracket 101. The slide support portion 107 has a through hole extending in the left-right direction. A restricting hook 108 is supported on the slide support portion 107. The restricting hook 108 has a shaft-shaped slide portion 108a that is inserted into the through hole of the slide support portion 107 and is supported so as to be slidable in the left-right direction and rotatable. An operating portion 108b that is bent rearward is formed at the left end of the slide portion 108a. The driver can grip the operating portion 108b with their hand to operate the restricting hook 108 in the left-right direction. A hook portion 108c that is bent toward the right is formed at the rear end of the operating portion 108b.

[0022] The restriction hook 108 of this embodiment is formed by bending a single shaft-shaped member to form the respective portions 108a to 108c. It is preferable to install anti-vibration rubber between the restriction hook 108 and the slide support part 107. By installing anti-vibration rubber, it is possible to suppress the generation of abnormal noises and sounds caused by friction between the restriction hook 108 and the slide support part 107 due to vibrations during driving, etc. Also, the anti-vibration rubber can apply frictional resistance to the sliding movement of the restriction hook 108, thereby preventing the restriction hook 108 from accidentally moving due to vibrations while driving. Furthermore, in order to prevent the restriction hook 108 from accidentally moving while driving, it is also possible to install a ring, hairpin, or through-pin, for example, on the right end of the slide part 108a of the restriction hook 108 that has moved to the rotation restriction position to prevent it from coming out.

[0023] 3 and 4, seating sensor 109 is supported in the opening of seat bracket 101. Seat sensor 109 has arm 109a that extends diagonally upward and is rotatable around its lower end. Arm 109a is capable of coming into contact with the underside of seat 20. Therefore, when pressed by the underside of seat 20, the angle of rotation of arm 109a changes, and seating sensor 109 can detect the position of seat 20 by detecting the angle of rotation of arm 109a. Arm 109a is biased by a spring (not shown) so that the tip of arm 109a faces upward. It is preferable that the seating sensor 109 is fixed via a spacer for position adjustment rather than directly to the seat bracket 101. By using the spacer, it is possible to easily adjust for individual differences in the seating sensor 109 and positional deviations over time.

[0024] 3 to 5, seat 20 of the embodiment has a base portion 111 which is the lower portion, and a backrest portion 112. In FIGS. 3 and 5, a rotatably supported portion 113 is supported at the front end portion of the underside of base portion 111. Rotatably supported portion 113 is rotatably supported by shaft support portion 102 via seat rotation shaft 114. Therefore, seat 20 of the embodiment can rotate forward around seat rotation shaft 114.

[0025] A rotation-restricted portion 116 is supported at the rear end of the underside of the base portion 111. A restricted hole 116a is formed at the rear end of the rotation-restricted portion 116. In this embodiment, the restricted hole 116a is formed as an elongated hole extending in the front-to-rear direction. When the seat 20 is moved to the seating position shown in FIG. 3, the rotation-restricted portion 116 moves to a position corresponding to the rotation restrictor 106. The hook portion 108c can penetrate the restricted hole 116a. Therefore, the rotation restrictor 106 can move between a rotation-restricted position shown in FIG. 6(A) where the hook portion 108c penetrates the restricted hole 116a and a rotatable position shown in FIG. 6(B) where the hook portion 108c is separated from the restricted hole 116a. When the rotation restrictor 106 is moved to the rotation-restricted position, the hook portion 108c is caught in the restricted hole 116a, restricting forward rotation of the seat 20. Therefore, unintentional rotation of the seat 20 while driving is suppressed, allowing for safe driving. When the rotation restricting device 106 moves to the rotatable position, the seat 20 becomes rotatable forward around the seat rotation axis 114 .

[0026] Figure 7 is an explanatory diagram of the state of the seat in the embodiment, where Figure 7(A) is an explanatory diagram of the seating position, Figure 7(B) is an explanatory diagram of the state of the seat spring in the seating position, Figure 7(C) is an explanatory diagram of the leaving position, Figure 7(D) is an explanatory diagram of the state of the seat spring in the leaving position, Figure 7(E) is an explanatory diagram of the state when the rotation restricting device is separated from the rotation restricted part, Figure 7(F) is an explanatory diagram of the state of the seat spring in the state of Figure 7(E), and Figure 7(G) is an explanatory diagram of the state when the seat is rotated forward. 3, 7(A), and 7(B), when the driver 121 is seated in the seat 20, the seat 20 moves to a seated position, which is an example of the second position. In the seated position, the seat spring 104 is compressed by the weight of the seat 20 and the weight of the driver, and the seat support portion 103 comes into contact with the underside of the seat 20. In this state, the rotation restricting device 106 can be moved (operated) between the rotation restricting position and the rotatable position. At this time, the arm portion 109a comes into contact with the underside of the seat 20 and is pressed downward, and the seat sensor 109 detects that the seat is in the seated position.

[0027] 7(C) and 7(D), when the driver 121 leaves the seat 20 or lifts his / her hips, the seat spring 104 elastically restores its original shape, causing the seat 20 to rotate forward. At this time, if the rotation restrictor 106 is in the rotation restricting position, the hook portion 108c and the restricted hole 116a are engaged, and the seat 20 is held in the leaving position shown in FIGS. 7(C) and 7(D), which are examples of the first position. In the leaving position, the arm portion 109a is in contact with the underside of the seat 20, just like in the sitting position, but its tip is rotated upward compared to the sitting position. Therefore, the rotation angle of the arm portion 109a changes relative to the sitting position, and the seat sensor 109 can detect that the seat has been moved to the leaving position.

[0028] In FIGS. 7(E) and 7(F), when the driver 121 leaves the seat 20, if the rotation restricting device 106 is in the rotatable position, the rotation of the seat 20 is not restricted by the rotation restricting device 106. Therefore, the seat spring 104 pushes up the seat 20, and the seat 20 moves to the separated position shown in FIGS. 7(E) and 7(F), which is an example of the third position. In the separated position of the embodiment, the arm 109a is separated from the seat 20, and the arm 109a rotates further than the separated position to its upper limit position. Therefore, by detecting the rotation angle of the arm 109a that has moved to the upper limit position, it is possible to detect that the seat sensor 109 has moved to the separated position. In the embodiment, as shown in FIG. 7(G), even when the seat 20 is rotated forward from the separated position, the arm 109a of the seat sensor 109 is not in contact with the seat and remains in its upper limit position. Therefore, the detection result indicates that the seat 20 has moved to the separated position. In the embodiment, the seat 20 is rotated forward around the front end of the seat 20, but the present invention is not limited to this. The present invention is also applicable to a configuration in which the seat 20 rotates backward.

[0029] 3, the control unit C of the traveling vehicle 1 of the embodiment controls the engine 12 based on the detection result of the seating sensor 109. Specifically, while the seating sensor 109 detects that the vehicle is in a seated position while the engine 12 is running, the control unit C does not perform control to stop the engine 12. Furthermore, if the seat sensor 109 detects the driver in the seat-away position or a position between the seated and seat-away positions for a predetermined period of time (for example, five seconds) while the engine 12 is running, the control unit C performs control to stop the engine 12. In this state, the driver continues to drive with his hips raised and sitting shallowly on the seat 20, or the driver drives while standing up, which is dangerous as there is a risk of the driver falling over due to a sudden stop or unexpected vibration, causing an accident. Therefore, if no seating is detected for a predetermined period of time, the engine 12 is stopped to improve safety.

[0030] Furthermore, in this embodiment, if the seat sensor 109 detects that the seat is in the away position or that the seat is in a position between the away position and the away position while the engine 12 is running, control is performed to immediately stop the engine 12. When the seat sensor 109 detects the away position, the rotation of the seat 20 is not restricted (locked) by the rotation restricting device 106, and there is a risk that the seat 20 may rotate due to a sudden stop or unexpected vibration, and the driver may be thrown out. Therefore, in this embodiment, if it is detected that the rotation restricting device 106 has not moved to the rotation restricting position, the engine 12 is immediately stopped to improve safety.

[0031] In this embodiment, by making regulated hole 116a an elongated hole, seat 20 can be moved within the range in which hook portion 108c can move along the elongated hole, and when leaving the seat, seat 20 can be moved from the seated position to the left position by the force of seat spring 104. While this configuration is desirable, it is also possible to make regulated hole 116a a round hole so that seat 20 does not move from the seated position even when leaving the seat.

[0032] FIG. 8 is an explanatory diagram of the armrest portion of the embodiment. FIG. 9 is an explanatory view of the cover member of the armrest in FIG. FIG. 10 is an explanatory diagram of a groove for a main speed change lever provided in the armrest of FIG. FIG. 11 is a side view of the main speed change lever portion of the armrest shown in FIG. FIG. 12 is an explanatory diagram of the main parts of the main shift lever, with FIG. 12(A) being a view from diagonally rear, FIG. 12(B) being a view from diagonally front, and FIG. 12(C) being a view from the side. 8 to 12, in the traveling vehicle 1 of the embodiment, an armrest 201 as an example of an armrest is arranged on the right side of the seat 20. Note that the armrest 201 of the embodiment does not move in conjunction with the seat 20. Armrest 201 is integrally formed with rear armrest body 202 and front lever operating section 203. In Figures 8 and 9, cover member 204 of lever operating section 203 has rear cover section 204a on which armrest cushion member 205 is supported, and front cover section 204b on which main speed change lever 206, lift lever 207, and buttons 208, 209 such as an automatic lowest button are arranged.

[0033] The right side (outside) of the cover front part 204b is formed with a front right groove 204c and a rear switch housing opening 204d. The right groove 204c is formed as a longitudinally extending groove corresponding to the range of movement of the lifting lever 207. As an example, a button 208 is disposed in the switch housing opening 204d for automatically moving the seedling planting device 3 to its lowest position. A front left groove 204e and a rear switch housing opening 204f are formed on the left side (inside) of the cover front part 204b. As an example, a button 209 for automatically maintaining the vehicle speed of the traveling vehicle body 1 at a predetermined vehicle speed is disposed in the switch housing opening 204f. In addition, a convex partition 210 extending in the front-to-rear direction is formed between the right groove 204c and the left groove 204e, which reduces the chance of accidentally confusing and operating the lift lever 207 and the main shift lever 206 compared to when the partition 210 is not present.

[0034] 9 and 10, the left groove 204e is formed in the shape of a crank groove extending in the longitudinal direction corresponding to the range of movement of the main shift lever 206. That is, the left groove 204e has a lever shift groove 211 extending in the longitudinal direction at the front, a pedal shift groove 212 extending in the longitudinal direction at the rear, and a connecting groove 213 extending in the lateral direction to connect the lever shift groove 211 and the pedal shift groove 212. In the traveling vehicle 1 of the embodiment, when the main shift lever 206 is operated along the lever shift groove 211, gears can be changed between 1 to 9 when working in a field, etc. Furthermore, when the main shift lever 206 is moved to the pedal shift groove 212, gears can be changed in accordance with the amount of depression of the accelerator pedal when traveling on a road, etc. It is more preferable to increase the length of the pedal gear shift groove portion 212 in the front-to-rear direction (longitudinal direction), as this makes it easier to visually see that the main gear shift lever 206 has been operated into the pedal gear shift groove portion 212.

[0035] 11 and 12, main speed change lever 206 of the embodiment has a base member 223 supported on a plate-shaped frame 221 so as to be rotatable about a rotation shaft 222. Frame 221 is formed with an arc-shaped guide groove 221a centered on rotation shaft 222. The base member 223 has a link support portion 224 extending rearward. A link pin 226 is supported on the link support portion 224. The link pin 226 passes through a guide groove 221a and guides the movement of the base member 223. The link pin 226 passes through a long hole 227a in a link arm 227 on the outside of the base member 223. The rear end of the link arm 227 is rotatably supported by the frame 221. A main speed change sensor 228 that detects the amount of rotation of the link arm 227 is disposed at the rear end of the link arm 227. Therefore, when the base member 223 rotates, the link arm 227 rotates via the link pin 226 and the long hole 227a. Therefore, the amount of rotation of the base member 223, i.e., the forward / rearward operating position and operating amount of the main speed change lever 206, can be detected by the main speed change sensor 228.

[0036] A pair of front and rear flanges 231 extending to the left are formed on the upper part of the base member. A lever body 233 is rotatably supported between the flanges around a second rotation shaft 232 extending in the front-to-rear direction. A stopper 234 is disposed on the left end of the flange 231, which contacts and stops the lever body 233 if it moves excessively to the left. In addition, a torque spring 235 is disposed on the second rotation shaft 232, which applies a force to return the lever body 233 to the right, i.e., toward the lever gear shift groove 211. As an example, the second rotation shaft 232 can be configured by combining a bolt and a U-nut.

[0037] Therefore, the lever body 233 can move left and right around the second rotation axis 232, and can be operated between the lever gear shifting groove 211 and the pedal gear shifting groove 212 by passing through the connecting groove 213. Although the example has been given in which the operating position of main shift lever 206 is detected by main shift sensor 228, this is not limiting. For example, a sensor that detects the amount of rotation about second rotation shaft 232 can be installed to detect whether main shift lever 206 is operated toward lever shift groove 211 or toward pedal shift groove 212. In this case, the position toward lever shift groove 211 can be set as a reference position (initial position, default), or the position toward pedal shift groove 212 can be set as the reference position. [Explanation of symbols]

[0038] 1...Traveling vehicle body, 12...Engine, 20…seats, 101...seat bracket, 103...seat support part, 104...seat spring, 106...Rotation control device, 109... seating sensor, 114...rotation axis, C...Control unit.

Claims

1. A traveling vehicle body (1), a seat (20) on which a driver who drives the traveling vehicle body (1) can sit; a seat bracket (101) disposed on the traveling vehicle body (1) and supporting the seat (20) rotatably in the front-rear direction around a rotation axis (114) at one end of the seat (20) in the front-rear direction; a rotation restricting device (106) that can be attached and detached to the other end of the seat (20) in the front-rear direction and the other end of the seat bracket (101) in the front-rear direction, the rotation restricting device (106) restricting the rotation of the seat (20) when the other end of the seat (20) and the other end of the seat bracket (101) are attached; a seat spring (104) that applies a force to the seat (20) in a direction in which the seat (20) moves away from the seat bracket (101); a seat support portion (103) that contacts a lower portion of the seat (20) and supports the seat (20) when the driver sits on the seat and the seat spring (104) is compressed; a seating sensor (109) that detects a first position where the seat (20) is pushed up by the seat spring (104) and a second position where the seat support part (103) supports the lower part of the seat (20) to detect whether the driver has left or sat in the seat; the seating sensor (109) for detecting a third position in which the seat (20) is rotated in a direction away from the seat bracket (101) from the first position; a control unit (C) that stops the engine (12) when the seat sensor (109) detects a position between the first position and the second position continuously for a predetermined period while the engine (12) is in operation, and that immediately stops the engine (12) when the seat sensor (109) detects the third position while the engine (12) is in operation; A work vehicle comprising:

2. The first position is a state in which the driver leaves the seat, the seat (20) is pushed in the rotational direction by the force of the seat spring (104), and the rotation is restricted by the rotation restricting device (106), so that the lower part of the seat (20) is separated from the seat support part (103).

2. The work vehicle according to claim 1.

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