JP2013053605A - Engine stop operation structure of working vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent an unnecessary engine stop caused by erroneously operating a forward/backward switching operation tool to a predetermined position for stopping an engine, while effectively preventing useless fuel consumption.SOLUTION: This engine stop operation structure of a working vehicle is constituted so as to stop the engine 7 based on predetermined operation of the forward/backward switching operation tool 40, and includes an operability different means A for making operability different from between an advance state and a retreat state when stopping the engine 7 by the predetermined operation of the operation tool 40.

Description

  The present invention relates to an engine stop operation structure for a work vehicle configured to stop an engine based on a predetermined operation of an operation tool for forward / reverse switching.

  A passenger rice transplanter, which is an example of a work vehicle, includes a main transmission lever that enables a shift operation and a forward / reverse switching operation of the main transmission as an operation tool for forward / reverse switching, and operates and guides the main transmission lever. A guide plate is provided with a switch for detecting the operation of the main shift lever to a predetermined position, and the lateral outer side of the forward shift path side in the left / right forward / backward switching path provided in the guide groove is set to a predetermined position for stopping the engine. There is one that is equipped and configured to stop the engine when a holding operation for a predetermined time at a predetermined position of the main shift lever is detected based on the output of the switch (see, for example, Patent Document 1).

Japanese Patent Laying-Open No. 2006-94753 (paragraph numbers 0039 and 0040, FIGS. 5 and 8)

  In the above configuration, the operation time required for the operation of the main shift lever from the forward shift path to the predetermined position is set to the predetermined position for stopping the engine on the lateral outer side of the forward shift path in the forward / reverse switching path of the guide groove. Can be shortened.

  On the other hand, when operating the main shift lever from the reverse shift path to the forward shift path along the forward / reverse switching path, the predetermined position for stopping the engine is located on the extension line of the operation. An erroneous operation to a predetermined position is likely to occur. Therefore, when operating the main speed change lever from the reverse speed change path to the forward speed change path, the main speed change lever may enter a predetermined position for stopping the engine and cause an inconvenience that the engine stops unnecessarily.

  In order to prevent such an unnecessary engine stop, it may be possible to lengthen the predetermined time for holding the main shift lever at a predetermined position for stopping the engine. Since the time required for the engine to stop after the operation becomes longer, there is room for improvement in preventing wasteful fuel consumption.

  An object of the present invention is to prevent an unnecessary engine stop caused by erroneously operating a forward / reverse switching operation tool to a predetermined position for stopping the engine while effectively preventing wasteful fuel consumption. .

In a first aspect of the present invention, there is provided an engine stop operation structure for a work vehicle configured to stop an engine based on a predetermined operation of an operation tool for forward / reverse switching.
Operability difference means is provided for differentiating the operability when the engine is stopped by a predetermined operation of the operation tool from a forward state and a reverse state.

  According to the first invention, for example, when a work vehicle often stops traveling after moving forward and performs auxiliary work, and when it is rare to stop traveling and perform auxiliary work after moving backward, there is a difference in operability. By the means, the operability when stopping the engine by a predetermined operation of the operating tool is made worse from the backward traveling state than from the forward traveling state. The time required for the operation to become easier and the engine to stop can be shortened, and it is difficult to perform the predetermined operation from the reverse operation state of the operation tool that is rarely performed, resulting in erroneous operation of the operation tool from the reverse operation state. It can be made difficult to cause an unnecessary engine stop.

  On the other hand, when the work vehicle stops traveling after reverse travel and performs auxiliary work in many cases, and it is rare that the work vehicle stops traveling after forward travel and performs auxiliary work, the operability difference means can By making the operability when stopping the engine by a predetermined operation worse from the forward state than from the reverse state, it becomes easier to perform the predetermined operation from the reverse state of the operation tool that is frequently performed. The time required to stop the engine can be shortened, and it is difficult to perform a predetermined operation from the advanced state of the operation tool which is rarely performed, and an unnecessary engine caused by an erroneous operation of the operation tool from the forward state. It can be made difficult to stop.

  In other words, by changing the operability when stopping the engine by a predetermined operation of the operating tool depending on the work vehicle between the forward state and the reverse state, waste due to the engine running during auxiliary work This can prevent unnecessary engine stoppage caused by misoperation of the operation tool for switching between forward and backward, while effectively preventing unnecessary fuel consumption, resulting in the engine stopping regardless of the driver's intention It is possible to prevent a decrease in work efficiency.

According to a second invention, in the first invention,
By the operability different means, the time required for the predetermined operation of the operation tool from the reverse state is longer than the time required for the predetermined operation of the operation tool from the forward movement state.

  According to the second invention, it is possible to shorten the time required until the engine is stopped by a predetermined operation from the advanced state of the operating tool. In addition, since the time required for the predetermined operation from the backward movement state of the operation tool becomes long, it becomes easy to cancel the erroneous operation until the predetermined operation is completed by the erroneous operation from the backward movement state of the operation tool.

  Accordingly, unnecessary fuel consumption due to the operation of the engine during the auxiliary work is effectively prevented, and unnecessary engine stoppage caused by an erroneous operation from the reverse state of the forward / backward switching operation tool is prevented. be able to.

According to a third invention, in the first or second invention,
The predetermined operation of the operation tool is a holding operation for a predetermined time at a predetermined position of the operation tool,
The operability different means is configured by varying the predetermined time.

  According to the third aspect of the present invention, it is possible to effectively prevent wasteful fuel consumption due to the operation of the engine during the auxiliary operation with a simple configuration in which the predetermined time for holding the operation tool in a predetermined position is varied. Further, it is possible to prevent an unnecessary engine stop caused by an erroneous operation of the operation tool for switching between the forward and backward movements.

4th invention is the said 1st or 2nd invention,
The predetermined operation of the operation tool is an operation to a predetermined position outside the normal operation path of the operation tool,
An inhibiting means for mechanically inhibiting the operation of the operation tool to a predetermined position is provided,
The operability difference means is configured by varying the degree of inhibition by the inhibition means.

  According to the fourth aspect of the present invention, the fuel is wasted due to the engine being operated during the auxiliary operation with a simple configuration in which the degree of mechanical inhibition of the inhibiting means for the operation of the operating tool to the predetermined position is varied. While preventing consumption effectively, it is possible to prevent an unnecessary engine stop caused by an erroneous operation of the operation tool for switching between forward and reverse.

  In addition, since the inhibition of the operation of the operation tool to the predetermined position is mechanically performed, it is easy to cope with a failure in the obstruction means, which is advantageous in terms of maintenance.

A fifth invention is the invention according to any one of the first to fourth inventions,
The operation tool is a shift operation tool that serves both as a forward / reverse switching and a gear shift,
The predetermined operation of the operation tool is an operation for performing an operation to at least a predetermined position connected to a neutral position of the speed change operation tool.

  According to the fifth aspect of the invention, when performing a predetermined operation of the speed change operation tool, it is necessary to operate the speed change operation tool to the neutral position. Therefore, when the engine is stopped by the predetermined operation of the speed change operation tool, By this operation, the traveling speed can be reduced to zero speed or a very low speed close thereto, and sudden deceleration accompanying stoppage of the engine can be avoided.

According to a sixth invention, in the first invention,
The operation tool is a shift operation tool that serves both as a forward / reverse switching and a gear shift,
The operation path of the shift operation tool is extended in the front-rear direction from the forward / reverse switching path in the left / right direction, the forward shift path extending from the one end of the forward / reverse switching path and the other end of the forward / backward switching path. And a reverse speed change path to be formed,
The predetermined operation of the shift operation tool is a holding operation for a predetermined time at a predetermined position connected to the left and right side ends of the forward / reverse switching path of the shift operation tool,
From the shift path farther from the predetermined position than the predetermined time when the shift operation tool is operated from the shift path closer to the predetermined position of the forward shift path and the reverse shift path to the predetermined position. The operability different means is configured by lengthening the predetermined time when operated to the predetermined position.

  According to the sixth aspect of the present invention, when the shift operating tool is operated from the shift path far from the predetermined position to the shift path close to the predetermined position along the forward / reverse switching path, the predetermined position is on the extension line of the operation. Is positioned, it is easy for an erroneous operation to a predetermined position of the speed change operation tool. Therefore, in the forward / reverse switching operation in which the shift operation tool is operated over the shift path near the predetermined position and the shift path far from the predetermined position, the shift operation tool is close to the predetermined position from the shift path far from the predetermined position. When operating the shift path on the side, the shift operation tool may accidentally enter a predetermined position, and the engine may be stopped by that operation regardless of the driver's intention.

  Therefore, the predetermined operation of the shift operation tool is a holding operation for a predetermined time at a predetermined position, and the shift operation tool is moved from the predetermined position to a predetermined position from the shift path closer to the predetermined position than the predetermined time. The shift operation tool is operated when the shift operation tool is operated from the shift path far from the predetermined position to the shift path closer to the predetermined position by lengthening the predetermined time when operated from the far shift path to the predetermined position. Even if the gear shifts into the predetermined position by mistake, it is possible to secure a time margin from when the shift operation tool enters the predetermined position until the predetermined operation is completed. It becomes easy to perform the detachment operation from the predetermined position.

  Therefore, it is possible to prevent a reduction in work efficiency due to the engine being stopped regardless of the driver's intention by erroneously entering the predetermined position during the forward / reverse switching operation.

It is the whole left side view of a riding rice transplanter. It is a whole top view of a riding rice transplanter. It is a schematic plan view which shows the transmission structure for driving | running | working. It is a schematic plan view which shows the transmission structure for work. It is a side view of the principal part which shows the speed change operation structure. It is a front view of the principal part which shows the speed change operation structure. It is a top view of the principal part which shows the speed change operation structure. It is a cross-sectional top view of the principal part which shows the operation path | route of a main transmission lever. It is a figure which shows the operation state to the 5th forward position of a main speed-change lever. It is a figure which shows the operation state to the reverse 3rd speed position of the main speed-change lever. It is a figure which shows the operation state to the neutral position of the main transmission lever. It is a block diagram which shows a control structure. It is a circuit diagram for starting and stopping an engine. It is a flowchart of engine stop control. It is a flowchart of engine starting control. It is a flowchart of operativity difference control. It is a cross-sectional top view of the principal part which shows the structure in another embodiment [4]. It is a cross-sectional top view of the principal part which shows the structure in another embodiment [5]. It is a cross-sectional top view of the principal part which shows the structure in another embodiment [6]. It is a cross-sectional top view of the principal part which shows the structure in another embodiment [7]. It is a cross-sectional top view of the principal part which shows the structure in another embodiment [8].

  Hereinafter, an embodiment in which an engine stop operation structure for a work vehicle according to the present invention is applied to a passenger rice transplanter as an example of a work vehicle will be described with reference to the drawings as an example for carrying out the present invention.

  As shown in FIGS. 1 and 2, the riding rice transplanter exemplified in this embodiment is based on the operation of a lifting cylinder 2 that employs a single-acting hydraulic cylinder at the rear of a traveling vehicle body 1 configured as a four-wheel drive type. Equipped with a parallel quadruple link type link mechanism 3 that swings up and down, and at the rear end of the link mechanism 3, a 6-row seedling planting device 4 can be rolled via a support shaft 5 facing forward and backward. It is connected. In other words, the seedling planting device 4 is connected to the rear portion of the traveling vehicle body 1 in a state where the seedling planting device 4 can be moved up and down by the operation of the lifting cylinder 2 and in a state where rolling using the support shaft 5 as a fulcrum is possible. And the fertilizer 6 for 6 strips is equipped over the rear-end part of the traveling vehicle body 1 and the seedling planting device 4. Thereby, it is comprised to the mid-mount fertilization specification for 6 rows planting which can plant and apply a maximum of 6 rows.

  As shown in FIGS. 1 to 4, the traveling vehicle body 1 belt-drives power from a water-cooled engine 7 that is anti-vibrated and mounted on the front thereof to the main transmission 8, and uses the power after the shift by the main transmission 8. A transmission case (hereinafter referred to as a T / M case) 9 is configured to branch into traveling and working. Then, after the driving power is transmitted to the auxiliary transmission 10 built in the T / M case 9 and the front wheel differential 11, it is taken out from the differential 11 through the left and right differential shafts 12. Power is transmitted to the left and right front wheels 13 for driving the front wheels, and the power extracted from the transmission gear 15 that rotates integrally with the differential case 14 is transmitted to the relay transmission shaft 17 from the T / M case 9 to the rear axle case 16, and The rear wheel drive shaft 18 and the left and right side clutches 19 incorporated in the rear axle case 16 are transmitted to the left and right rear wheels 20 for driving the rear wheels. Further, the one-way clutch 21, the inter-strain transmission 22, the planting clutch 23, and the work transmission shaft 24 extending from the T / M case 9 to the seedling planting device 4 are provided. , Etc., and is transmitted to the seedling planting device 4 so as to prevent the reverse operation of the seedling planting device 4. The rear axle case 16 is equipped with a multi-plate brake 25 that brakes the rear wheel transmission shaft 18. The brake 25 is configured to self-return to the brake release state.

  The engine 7 is a gasoline engine. The main transmission 8 employs a hydrostatic continuously variable transmission. The sub-transmission 10 employs a gear-type transmission that is configured to be capable of shifting in two levels, a low speed state for work travel and a high speed state for road travel. Each of the left and right side clutches 19 employs a multi-plate hydraulic clutch. The inter-strain transmission 22 employs a gear-type transmission configured to be capable of six speeds.

  As shown in FIGS. 1 and 2, the seedling planting device 4 has a lateral feed mechanism (not shown) in which a seedling placing table 26 on which a maximum of six mat-like seedlings are placed is powered by working power from the traveling vehicle body 1. )) And reciprocates with a constant stroke in the left-right direction. In addition, six rotary-type planting mechanisms 27 arranged so as to be arranged at regular intervals in the left-right direction corresponding to the mat-like seedlings of the seedling mounting table 26 receive planted seedlings from the lower end of the seedling mounting table 26. A predetermined amount is taken out and configured to be planted and supplied to a mud portion of a farm field leveled by three leveling floats 28 arranged in the left-right direction. Each time the seedling stage 26 reaches the left and right stroke ends, the belt-type vertical feed mechanism 29 is operated, and each mat-like seedling placed on the seedling stage 26 is directed toward the lower end of the seedling stage 26. It is configured to feed vertically at a predetermined pitch.

  Each leveling float 28 has the rear side thereof as a free end portion (rear end portion) of the corresponding support arm 31 among the three sets of support arms 31 extending rearward and downward from the left and right float fulcrum shaft 30. It is connected so that it can swing up and down.

  The fertilizer application device 6 transmits the power branched from the relay transmission shaft 17 via the power branch mechanism 32 for fertilization work. In the fertilizer application device 6, the four feeding mechanisms 33 mounted on the rear end of the traveling vehicle body 1 are operated by the power for fertilization work from the power branch mechanism 32, and are stored in the hopper 34 communicated with the upper part thereof. The granular fertilizer is fed out from the hopper 34 by a predetermined amount. Further, the electric blower 35 provided at the rear end of the traveling vehicle body 1 is operated by the electric power from the traveling vehicle body 1 to generate the conveying wind, so that the granular fertilizer fed by each feeding mechanism 33 is sent from the blower 35. Are supplied to corresponding ones of the groovers 37 respectively provided on the left and right sides of each leveling float 28 via a fertilizer hose 36 connected in communication with each feeding mechanism 33. It is comprised so that it may be buried in the mud of the field by the groove device 37.

  Each feeding mechanism 33 is configured for two strips capable of feeding a maximum of two granular fertilizers. Then, four feeding mechanisms are set by setting the feeding mechanisms 33 at the left and right ends to feed two granular fertilizers and the two feeding mechanisms 33 at the left and right central sides to feed one granular fertilizer. 33 is configured to feed out six rows of granular fertilizer.

  As shown in FIGS. 1 to 3, a riding operation unit 38 is formed at the rear of the traveling vehicle body 1. The boarding operation unit 38 includes a steering wheel 39 for steering the front wheels, a main transmission lever (an example of an operation tool) 40 that enables a transmission operation of the main transmission 8, and a sub-transmission that enables a transmission operation of the auxiliary transmission 10. A lever 41, a brake pedal 42 that enables a braking operation of the brake 25, a first work lever 43 and a second work lever 44 that enable a raising / lowering operation and switching of an operation state of the seedling planting device 4, and a driver's seat 45 etc. are deployed.

  Although not shown, the brake pedal 42 is configured to automatically return to the depression release position. The first work lever 43 can be swung to the planting, descending, neutral, rising, and automatic operation positions, and can be swung to the left and right at the planting position. It is configured. The second working lever 44 is configured to be a cross-reciprocating and neutral return type capable of swinging up and down and back and forth.

  As shown in FIGS. 1 and 2, preliminary seedling placement devices 46 are provided at the left and right ends of the front portion of the traveling vehicle body 1. Each preliminary seedling placement device 46 translates forward into a preliminary seedling frame 47 configured to be able to change the posture between a standing posture and a backward tilted posture by changing the posture of the preliminary seedling frame 47 from the standing posture to the forward leaning posture. In addition, the auxiliary frame 48 is equipped with a suspension frame 48 so that the auxiliary seedling frame 47 can be moved backward in parallel by changing the posture from the forward tilted posture to the standing posture. Are arranged at a predetermined interval, so that the preliminary seedling frame 47 is erected so that each of the preliminary seedling platforms 49 is located on the lateral side of the engine 7, and each preliminary seedling platform 49 is moved forward. The spare seedling frame 47 can be switched to a spare seedling supply state in which the preliminary seedling frame 47 is tilted forward so as to be displaced.

  As a result, when supplying the spare seedlings to the left and right spare seedling placement devices 46 from the heel performed with the front end of the traveling vehicle body 1 close to the heel, the left and right spare seedling placement devices 46 are switched to the spare seedling supply state. Thus, it is possible to bring all the spare seedling mounts 49 of the left and right spare seedling placement devices 46 closer to the cocoon, and it is possible to facilitate the supply of the spare seedlings from the heel in front of the vehicle body to each of the spare seedling placement stands 49. .

  As shown in FIGS. 5 to 7, the main speed change lever 40 is integrated in a front-rear direction with a swing plate 53 that is connected to a support bracket 51 fixed to the steering post 50 via a left-right support shaft 52 so as to be able to swing back and forth. The support shaft portion 40A is connected to the swing plate 53 so as to be rotatable relative to the swing plate 53 so that it can swing and can be independently swung in the left-right direction. Further, the torsion spring 54 externally fitted to the support shaft portion 40A is urged to swing so that the upper side extending upward from the support shaft portion 40A swings and displaces in the right direction.

  The oscillating plate 53 is displaced in the vertical direction in conjunction with the oscillating back and forth of the oscillating plate 53 so that neutral operation, forward shift operation, and reverse shift operation of the main transmission 8 by the main transmission lever 40 can be performed. The first linkage rod 56, the swinging member 58 that swings back and forth with the left and right support shaft 57 as a fulcrum in conjunction with the displacement of the first linkage rod 56, and the front and rear in conjunction with the back and forth swing of the swinging member 58 The shift of the main transmission 8 via the second linkage rod 59 that is displaced in the direction and the operation arm 60 that rotates the transmission operation shaft 8A of the main transmission 8 in conjunction with the displacement of the second linkage rod 59. It is linked to the operation shaft 8A. The operation arm 60 is formed to have a function as a cam member of a neutral return mechanism 61 that urges the shift operation shaft 8A of the main transmission 8 to return to the neutral position.

  As shown in FIGS. 5, 6, and 8, an engaging portion 40 </ b> B that engages with a guide groove 55 </ b> A of the guide plate 55 connected to the support bracket 51 is provided at the lower end portion of the main transmission lever 40. The guide groove 55A includes a left / right forward / reverse switching path 55a serving as a neutral position of the main transmission lever 40, a forward transmission path 55b extending rearward from the left end of the forward / reverse switching path 55a, and a right end of the forward / reverse switching path 55a. A crank-shaped main guide portion 55Aa as a normal operation path having a reverse speed change path 55c extending forward from the left side, and an auxiliary guide section 55Ab connected to a left end of the forward / reverse switching path 55a in a state extending leftward. It is formed as follows. The left end portion of the auxiliary guide portion 55Ab interrupts the planting operation and transfers the matted seedlings from the preliminary seedling mounting base 49 to the seedling mounting base 26, or fertilizer replenishment for supplying fertilizer to the hopper 34 of the fertilizer application device 6. Or, when performing auxiliary work such as elimination of fertilizer clogging in the fertilizer application device 6, the engine as the predetermined position P that enables the engine 7 to be switched from the operating state to the stopped state by operating the main transmission lever 40. The stop position 55d is set.

  Between the support bracket 51 and the oscillating plate 53, a main transmission lever 40 and a main transmission device 8 are arranged for neutral transmission of the main transmission lever 40 and the main transmission 8 and at the respective transmission positions of the fifth forward speed and the third reverse speed. A detent mechanism 62 is provided. Further, the guide plate 55 prevents the main transmission lever 40 from moving to the engine stop position 55d due to the action of the torsion spring 54, and allows the manual transmission of the main transmission lever 40 to the engine stop position 55d and the engine. A detent mechanism 63 for stopping the engine that enables holding at the stop position 55d is provided.

  Although not shown, the sub-shift lever 41 is configured to be able to be switched and held between a low speed position for work travel and a high speed position for road travel by a swinging operation in the front-rear direction. The sub-transmission device 10 is switched via a sub-transmission mechanical linkage mechanism such as a linkage rod so that the sub-transmission device 10 switches between a low speed state for work travel and a high speed state for mobile travel according to the operation position. The transmission 10 is linked.

  As shown in FIG. 3 and FIGS. 9 to 11, the brake pedal 42 is braked via a braking mechanical linkage mechanism 64 made up of a linkage rod or the like so as to obtain a braking force corresponding to the depression operation amount. It is linked to. Further, when the main speed change lever 40 is operated to the forward speed change path 55b or the reverse speed change path 55c, the speed change position at that time is higher than the speed change position corresponding to the depression operation amount of the brake pedal 42. In conjunction with the depression operation of the brake pedal 42, the main transmission lever 40 is decelerated to a shift position corresponding to the depression operation amount of the brake pedal 42 against the action of the detent mechanism 62 for main transmission, A pair of linkage pins provided on the swing member 58 for main transmission operation so that the main transmission lever 40 returns to the neutral position (the forward / reverse switching path 55a of the main guide portion 55Aa) when reaching the stepping limit position. 58A and 58B are linked via a neutral linkage mechanical linkage mechanism 65. With this linkage, when the brake pedal 42 is depressed to operate the brake 25 in a traveling state in which the main transmission lever 40 is operated to the forward transmission path 55b or the reverse transmission path 55c, the operation of the brake pedal 42 is interlocked. The main transmission 8 is decelerated together with the main transmission lever 40, and when the brake pedal 42 reaches the depressing limit position, the main transmission lever 40 returns to the neutral position 55a and the main transmission 8 cuts off the transmission. It is configured to return to the state.

  9 shows a state in which the main transmission lever 40 is operated and held at the forward fifth speed position, FIG. 10 shows a state in which the main transmission lever 40 is operated and held at the reverse third speed position, and FIG. The main speed change lever 40 has returned to the neutral position 55a in conjunction with the stepping operation of No. 42.

  As shown in FIG. 12, the traveling vehicle body 1 is equipped with an electronic control unit (hereinafter referred to as ECU) 66 configured using a microcomputer including a CPU, an EEPROM, and the like. The ECU 66 has control programs such as a lifting control means 66A for controlling the raising and lowering of the seedling planting device 4, and a work operation control means 66B for switching the seedling planting device 4 and the fertilizer application device 6 between an operating state and a stopped state. I have.

  The lift control means 66A is a second lever sensor that detects the output of the first lever sensor 67 that detects the operation position of the first work lever 43 in the front-rear direction, and the operation of the second work lever 44 in the vertical direction and front-rear direction. 68, the output of the float sensor 69 that detects the vertical swing angle of the leveling float 28 (hereinafter referred to as the center float) 28 as the height to the ground of the seedling planting device 4, and the vertical swing of the link mechanism 3 The seedling planting device 4 is controlled by controlling the operation of the lifting valve 71 that switches the operating state of the lifting cylinder 2 based on the output of the link sensor 70 that detects the moving angle as the height of the seedling planting device 4 with respect to the vehicle body. It is comprised so that raising / lowering of this may be controlled.

  Specifically, when an operation to the raised position of the first work lever 43 is detected based on the output of the first lever sensor 67, the lift valve 71 is switched to a supply state in which oil is supplied to the lift cylinder 2. Then, the raising / lowering cylinder 2 is contracted to raise the seedling planting device 4. When the operation of the first working lever 43 to the lowered position is detected based on the output of the first lever sensor 67, the lifting cylinder 2 is switched by switching the lifting valve 71 to a discharging state in which oil is discharged from the lifting cylinder 2. Lowering control is performed to lower the seedling planting device 4 by extending the seedling. When an operation to the neutral position of the first work lever 43 is detected based on the output of the first lever sensor 67, the lift valve 71 is switched to a supply / discharge stop state in which the oil supply / discharge to the lift cylinder 2 is stopped. Then, the lifting / lowering stop control is performed to stop the operation of the lifting / lowering cylinder 2 and stop the seedling planting device 4 at the height position at that time.

  That is, the seedling planting device 4 can be moved up and down to an arbitrary height position by the control operation of the lifting control means 66A based on the output of the first lever sensor 67.

  When the lift control means 66A detects an operation of the first work lever 43 to the automatic position based on the output of the first lever sensor 67, the lift control means 66A detects the operation of the lift valve 71 based on the output of the second lever sensor 68 and the like. Control the operation.

  For example, when the downward operation of the second work lever 44 is detected based on the output of the second lever sensor 68, the lifting cylinder 71 is switched to the discharging state, so that the lifting cylinder 2 is extended and seedling planting is performed. When the apparatus 4 is lowered, the center float 28 is grounded by this lowering, and the output of the float sensor 69 matches the preset control target angle of the center float 28 (the output of the float sensor 69 is within the dead zone width of the control target angle). The lifting / lowering valve 71 is switched to a supply / discharge stop state to stop the extension operation of the lifting / lowering cylinder 2 and the seedling planting device 4 has a predetermined contact height position (work) corresponding to the control target angle. Perform automatic descent control to stop automatically at the height position. Thereafter, the operation of the elevating valve 71 is controlled to switch the operating state of the elevating cylinder 2 so that the state where the output of the float sensor 69 coincides with the control target angle is caused by the ups and downs of the field cultivator. Automatic raising / lowering control for automatically raising / lowering the seedling planting device 4 so as to obtain a state in which the seedling planting device 4 maintains a predetermined ground contact height position regardless of the pitching of the traveling vehicle body 1 is performed. When the upward operation of the second working lever 44 is detected based on the output of the second lever sensor 68, the lifting cylinder 71 is contracted by switching the lifting valve 71 to the supply state, so that seedling planting is performed. As the device 4 is raised, the rise of the output of the link sensor 70 matches the preset control upper limit angle of the link mechanism 3 (the output of the link sensor 70 falls within the dead zone width of the control upper limit angle). By switching the raising / lowering valve 71 to the supply / discharge stop state, automatic raising control is performed in which the contraction operation of the raising / lowering cylinder 2 is stopped and the seedling planting device 4 is automatically stopped at a predetermined upper limit position corresponding to the control upper limit angle.

  That is, by the control operation of the lifting control means 66A based on the output of the second lever sensor 68, the seedling planting device 4 is automatically moved up and down to a predetermined grounding height position or a predetermined upper limit position, and their heights are increased. Can be maintained in position.

  The control target angle of the center float 28 can be set and changed to an arbitrary angle by operating a float angle setting unit 72 provided in the boarding operation unit 38. A rotary potentiometer is employed for the float angle setting device 72 and the first lever sensor 67, the float sensor 69, and the link sensor 70 described above. The second lever sensor 68 is a multi-contact switch. An electromagnetic control valve is adopted as the lift valve 71.

  The work motion control means 66B is an electric planting clutch motor that intermittently operates the planting clutch 23 based on the output of the first lever sensor 67, the output of the second lever sensor 68, the output of the float sensor 69, and the like. 73, controls the operation of an electric fertilizer clutch motor 75 that intermittently operates the fertilizer clutch 74 provided in the power branch mechanism 32, and a blower relay 77 that intermittently energizes the blower 35 from the battery 76 mounted on the traveling vehicle body 1. Thus, the seedling planting device 4 and the fertilizer application device 6 are configured to be switched between an operating state and a stopped state.

  Specifically, after detecting the operation from the neutral position to the lowered position of the first work lever 43 based on the output of the first lever sensor 67, the ground contact of the center float 28 is detected based on the output of the float sensor 69. In this case, a blower start control is performed to start the blower 35 by switching the blower relay 77 to a closed state in which the blower relay 77 is allowed to be energized from the battery 76 to the blower 35. Thereafter, when the operation of the first working lever 43 to the planting position is detected based on the output of the first lever sensor 67, the planting clutch 23 and the fertilizer application clutch 74 are planted so as to switch from the cut state to the on state. The clutch engagement control for controlling the operation of the attached clutch motor 73 and the fertilizer application clutch motor 75 is performed. Thereby, the seedling planting device 4 and the fertilizer application device 6 are switched from the stopped state to the activated state.

  When the operation of the first working lever 43 from the planting position to the lowered position is detected based on the output of the first lever sensor 67 in the operating state of the seedling planting device 4 and the fertilizer application device 6, the blower relay 77 The blower stop control for stopping the blower 35 is performed by switching the blower relay 77 to an open state in which the power supply from the battery 76 to the blower 35 is blocked by stopping the energization of the blower 35. Further, clutch disengagement control is performed to control the operation of the planting clutch motor 73 and the fertilizer clutch motor 75 so that the planting clutch 23 and the fertilizer clutch 74 are switched from the on state to the disengaged state. Thereby, the seedling planting device 4 and the fertilizer application device 6 are switched from the operating state to the stopped state.

  When the work operation control unit 66B detects an operation of the first work lever 43 to the automatic position based on the output of the first lever sensor 67, the blower described above based on the output of the second lever sensor 68 or the like. Start control, blower stop control, clutch engagement control, and clutch disengagement control are performed.

  For example, after detecting the operation of the first working lever 43 to the automatic position based on the output of the first lever sensor 67, or operating the second working lever 44 upward based on the output of the second lever sensor 68. When the first operation below the second work lever 44 is detected based on the output of the second lever sensor 68, the blower start control described above is performed. Thereafter, when the second operation of the second working lever 44 is detected downward based on the output of the second lever sensor 68, the seedling planting device 4 is based on the outputs of the float angle setting device 72 and the float sensor 69. The clutch engagement control described above is performed in accordance with the detection of the arrival at a predetermined ground contact height position. Thereby, the seedling planting device 4 and the fertilizer application device 6 are switched from the stopped state to the activated state.

  Further, in the operating state of the seedling planting device 4 and the fertilizer application device 6, when the upward operation of the second work lever 44 is detected based on the output of the second lever sensor 68, the blower stop control and clutch described above are performed. Performs cutting control. Thereby, the seedling planting device 4 and the fertilizer application device 6 are switched from the operating state to the stopped state.

  As shown in FIG. 12, the ECU 66 includes a marker posture control unit 66 </ b> C that controls the postures of the pair of left and right drawing markers 78 provided on the left and right sides of the seedling planting device 4 as a control program.

  Although not shown in the drawings, the left and right drawing markers 78 are configured so that the posture can be switched between the retracted posture and the action posture by a horizontal swinging operation. In the retracted posture, the seedling planting device 4 The rotating reference line forming rotator provided on the free end portions of the rotating end portions is separated from the field mud surface, and in the acting posture, As the traveling reference line-forming rotator enters the field mud surface and travels along the current traveling route, the traveling reference line used in the next traveling route is It will be in a state of forming on the surface.

  The marker posture control means 66C includes an output of the auxiliary lever sensor 79 that detects an operation in the left-right direction at the planting position of the first work lever 43, an output of the first lever sensor 67, an output of the second lever sensor 68, and Based on the outputs of the left and right marker sensors 80 that detect the arrival of the corresponding drawing marker 78 in the retracted position and the action posture, the operation of the electric left and right marker motors 81 that swing the corresponding drawing marker 78 is controlled. By doing so, the left and right drawing markers 78 are configured to be switched between the retracted posture and the acting posture.

  Specifically, when an operation from the planting position of the first work lever 43 to the left is detected based on the output of the auxiliary lever sensor 79, the left line drawing marker 78 is based on the output of the left marker sensor 80. The left marker motor 81 is rotated forward until the left-hand marker 78 is projected to the left outer side until the movement posture is detected. On the contrary, when an operation from the planting position of the first work lever 43 to the right is detected based on the output of the auxiliary lever sensor 79, the action of the right drawing marker 78 is based on the output of the right marker sensor 80. Right marker overhanging control is performed in which the right marker motor 81 is rotated forward until the right drawing marker 78 is projected outwardly until the arrival of the posture is detected. When the operation of the first work lever 43 from the planting position to the lowered position is detected based on the output of the first lever sensor 67, the marker sensor 80 corresponding to the drawing marker 78 in the action posture is Marker storage control is performed in which the marker motor 81 corresponding to the drawing marker 78 in the acting posture is reversely operated until the reaching to the retracted posture is detected to store the drawing marker 78 in the acting posture.

  Further, when the operation of the first work lever 43 to the automatic position is detected based on the output of the first lever sensor 67, the above-described left marker overhang control and right marker overhang control are performed based on the output of the second lever sensor 68. , And marker storage control.

  Specifically, when the forward operation of the second work lever 44 is detected based on the output of the second lever sensor 68, the left marker overhang control described above is performed, and conversely, the rear of the second work lever 44 When the operation is detected, the right marker extension control described above is performed. When the upward operation of the second work lever 44 is detected, the marker storage control described above is performed.

  The auxiliary lever sensor 79 includes a limit switch arranged on the left side of the planting position so as to detect an operation to the left at the planting position of the first work lever 43, and a planting position of the first work lever 43. It is composed of a limit switch arranged on the right side of the planting position so as to detect the operation to the right in the case. Each of the left and right marker sensors 80 includes a limit switch that detects arrival of the corresponding drawing marker 78 to the retracted posture and a limit switch that detects arrival of the acting posture.

  As shown in FIG. 12, the ECU 66 is provided with a rolling control means 66D as a control program for controlling the rolling angle of the seedling planting device 4 with the support shaft 5 facing forward and backward.

  Based on the output of the rolling sensor 82 mounted on the seedling planting device 4 so as to detect the rolling angle of the seedling planting device 4 with the support shaft 5 facing forward and backward as the fulcrum, the rolling control means 66D The support shaft 5 facing forward and backward is supported so that the output matches the preset control target angle of the seedling planting device 4 (the output of the rolling sensor 82 falls within the dead zone width of the control target angle). The operation of an electric rolling motor 83 provided in a rolling mechanism (not shown) for changing the rolling angle of the seedling planting device 4 with respect to the traveling vehicle body 1 is controlled.

  The control target angle of the seedling planting device 4 can be set and changed to an arbitrary angle by operating a rolling angle setting device 84 provided in the boarding operation unit 38.

  When the operation position of the rolling angle setter 84 is the reference position, the rolling control unit 66D determines that the output of the rolling sensor 82 matches the output at the reference position of the rolling angle setter 84. By controlling the operation, horizontal control is performed to maintain the seedling planting device 4 in a horizontal posture regardless of the rolling of the traveling vehicle body 1 caused by ups and downs of the tiller.

  In addition, when the operation position of the rolling angle setting device 84 is changed from the reference position to an arbitrary operation position that takes into account the inclination of the tilling board at the edge of the paddle or the like, the output of the rolling sensor 82 is changed after the setting change. By controlling the operation of the rolling motor 83 so as to match the output of the rolling angle setter 84, the seedling planting device 4 can be moved to any position other than the horizontal posture regardless of the rolling of the traveling vehicle body 1 due to the ups and downs of the tiller etc. Tilt control to maintain the rolling posture set to.

  In addition, in order to detect the rolling angle of the seedling planting apparatus 4 with high accuracy and high responsiveness, the rolling sensor 82 includes a tilt angle sensor and an angular velocity sensor. The rolling angle setter 84 employs a rotary potentiometer.

  As shown in FIG. 12, the ECU 65 includes a lift valve 71, a planting clutch motor 73 based on the output of a rudder angle sensor 86 that detects an operation angle from a straight position of the pitman arm 85 as a steering angle of the front wheel 13. A turning control means 66E for controlling the operation of the fertilizing clutch motor 75, the blower relay 77 and the pair of turning valves 87 for controlling the flow of oil to the corresponding side clutch 19 is provided as a control program.

  Based on the operation of the first selection switch 88 for turning control provided in the boarding operation unit 38, the turning control means 66E can select the clutch turning control that can execute the clutch turning control and the clutch turning control selection that prohibits the execution. Switch to the released state. Further, based on the operation of the second selection switch 89 for turning control provided in the boarding operation unit 38, the turning start raising control selection state in which the turning start raising control can be executed and the turning start raising control selection which is prohibited from being executed are cancelled. Switch to state. Further, based on the operation of the third selection switch 90 for turning control provided in the boarding operation unit 38, the turning end lowering control selection state in which the turning end lowering control can be executed, and the turning end lowering control selection forbidden to execute are cancelled. Switch to state.

  In the clutch turning control selection state, when it is detected that the steering angle of the front wheel 13 has exceeded a set angle (for example, 30 degrees) based on the output of the steering angle sensor 86, the cornering turning that turns the vehicle body 180 degrees is performed. By determining that it has been started, switching the swing valve 87 corresponding to the side clutch 19 on the inner side of the swing to the discharge state for discharging the oil from the side clutch 19 and switching the side clutch 19 on the inner side of the swing from the on state to the disconnected state, The normal turning state in which the left and right rear wheels 20 are driven shifts from the normal turning state to the clutch turning state in which the rear wheel 20 on the inside of the turn is idled to reduce the turning radius. Thereafter, when it is detected that the steering angle of the front wheel 13 has decreased below the set angle, it is determined that the turning turn has ended, and the turning valve 87 corresponding to the side clutch 19 inside the turn is supplied to the side clutch 19 with oil. By switching to the supply state and switching the side clutch 19 inside the turning from the disengaged state to the engaged state, the clutch turning state is changed to the normal turning state.

  That is, by selecting the clutch turning control, the clutch turning with a small turning radius and the normal turning state according to the steering angle of the front wheel 13 at the time of the turning turning to shift from the current traveling route to the next adjacent traveling route. It is possible to smoothly transition to the state, and it is possible to easily perform the adjacent alignment at the time of turning.

  In the turning start raising control selection state, when it is detected that the steering angle of the front wheel 13 exceeds a set angle (for example, 30 degrees) based on the output of the steering angle sensor 86, it is determined that the coasting turning has started, The seedling planting device 4 and the fertilizer application device 6 are switched from the operating state to the stopped state by performing the blower stop control and the clutch disengagement control described above, and the seedling planting device 4 is predetermined by performing the upper limit automatic ascent control described above. Is automatically raised from the ground contact height position to a predetermined upper limit position.

  In other words, by selecting the turning start raising control, the operation of the seedling planting device 4 and the fertilizer application device 6 is switched from the operating state to the stopped state in conjunction with the front wheel steering exceeding the set angle performed at the start of the saddle turning. And the ascending movement of the seedling planting device 4 from the predetermined ground contact height position to the predetermined upper limit position can be appropriately performed.

  In the turning end descending control selection state, when it is detected that the steering angle of the front wheel 13 has decreased to a set angle (for example, 30 degrees) or less based on the output of the steering angle sensor 86, it is determined that the coasting turning has ended. The blower 35 is operated by performing the above-described blower start control, and the seedling planting device 4 is automatically lowered from the predetermined upper limit position to the predetermined ground contact height position by performing the above-described automatic lowering control, The seedling planting apparatus performs the above-described clutch engagement control as it detects the arrival of the seedling planting apparatus 4 to the predetermined ground contact height position based on the outputs of the float angle setting device 72 and the float sensor 69. 4 and the fertilizer applicator 6 are switched from the stopped state to the activated state.

  That is, by selecting the turning end descending control, the predetermined contact height position from the predetermined upper limit position of the seedling planting device 4 is interlocked with the front wheel steering to the set angle or less performed at the end of the turning turn. It is possible to appropriately perform the downward movement and the switching of the seedling planting device 4 and the fertilizer application device 6 from the stopped state to the activated state.

  Each swing valve 87 employs an electromagnetic control valve. Momentary switches are adopted for the selection switches 88 to 90.

  Although illustration is omitted, the seedling planting device 4 includes three auxiliary clutches for planting that intermittently transmit power to the planting mechanism 27 in one set of two strips, and a vertical feed mechanism 29 in one set of two strips. Three auxiliary clutches for vertical feed that interrupt transmission are provided. The fertilizer applicator 6 includes three fertilizer auxiliary clutches that intermittently transmit power to the feeding mechanism 33 in two pairs.

  The ECU 66 includes, as a control program, auxiliary clutch control means for controlling the operation of an electric auxiliary clutch motor linked to each auxiliary clutch through a mechanical linkage mechanism for auxiliary clutches. The auxiliary clutch control means performs an on / off operation with two sets of auxiliary clutches corresponding to each number selection switch based on the operation of three number selection switches composed of alternate switches provided in the boarding operation unit 38. Configured to do.

  Specifically, the auxiliary clutch control means is configured to turn on all auxiliary clutches for planting, vertical feed, and fertilizer application when no ON signal is output from all three number selection switches. The operation of the auxiliary clutch motor is controlled so that the strip working state is obtained. When an ON signal is output from the number selection switch for the left two strips, the auxiliary clutches for planting, vertical feed and fertilization for the left two strips are turned off, and the remaining auxiliary clutches The operation of the auxiliary clutch motor is controlled so as to obtain the right four-strip working state that is in the on state. If an ON signal is output from the number selection switch for the left 2 and middle 2 strips, the auxiliary clutches for planting, vertical feed and fertilizer application for the left 4 strips will be disengaged and the remaining The operation of the auxiliary clutch motor is controlled so that a right two-row working state in which each auxiliary clutch is engaged is obtained. When an ON signal is output from the right two-row selection switch, the planting, vertical feed, and fertilizer auxiliary clutches for the right two are turned off, and the remaining auxiliary clutches The operation of the auxiliary clutch motor is controlled so as to obtain the left four-strip working state that enters the engaged state. When an ON signal is output from the number selection switch for the right 2 and middle 2 strips, the auxiliary clutches for planting, vertical feed and fertilizer application for the right 4 strips are disengaged and the rest The operation of the auxiliary clutch motor is controlled so that the left two-row working state where each auxiliary clutch is engaged is obtained.

  As shown in FIGS. 12 and 13, the ECU 66 is activated by energization from the battery 76 obtained by operating the key operation type main switch 91 provided in the boarding operation unit 38 from the OFF position to the ON position. When the main switch 91 is turned off from the ON position to the OFF position, the energized state is maintained by a self-holding circuit (not shown) provided in the battery 76, and the battery 76 is turned off. Various information such as the total operating time of the engine 7 at the stage where the power supply is cut off and setting information by various selection switches 88 to 90 are stored in the EEPROM, and then the power supply by the self-holding circuit is stopped to stop the operation. To do. The main switch 91 is connected to an engine starter 93 via a brake switch 92 that is a limit switch.

  Although illustration is omitted, the brake switch 92 switches from the open state to the closed state as the brake pedal 42 reaches the depression limit position, and opens from the closed state as the brake pedal 42 leaves the depression limit position. It is configured to switch to a state.

  That is, only when the operation from the ON position of the main switch 91 to the START position is performed in the braking state of the brake 25 in which the brake pedal 42 is depressed to the depressing limit position, the battery 76 via the main switch 91 is switched to the starter 93. The engine 7 can be started by the operation of the starter 93 based on the operation of the main switch 91.

  As shown in FIGS. 5, 6, 8, 12, and 13, the ECU 66 is provided in parallel with the main switch 91 between the battery 76 and the brake switch 92 based on the operation of the main transmission lever 40. A control program for engine control means 66F that switches the engine 7 between the operating state and the stopped state by controlling the operation of the starter relay 94 and the igniter relay 96 that intermittently supplies power from the battery 76 to the igniter 95 of the engine 7 As prepared.

  Based on the operation of the engine control selection switch 97 provided in the boarding operation unit 38, the engine control unit 66F executes the engine stop control if the selected state regarding the execution of the engine stop control is the engine 7 is in an operating state. The first selection state to enable, the second selection state to enable execution of engine stop control in the planting work state (working device use state), and the execution of engine stop control in the coasting turning state Is switched to a third selection state in which the engine stop control is prohibited and an engine stop control selection release state in which the execution of the engine stop control is prohibited.

  Specifically, a momentary switch is employed as the engine control selection switch 97, and each time the selection switch 97 is pressed, the selection state related to execution of the engine stop control is the first selection state, It is switched to one of the 2 selection state, the 3rd selection state, and the selection cancellation state in the description order. The engine control selection switch 97 may employ a 4-position switching dial switch, a slide switch, or the like.

  In the first selection state, the operation of the main shift lever 40 to the engine stop position 55d is performed in a state where the operation of the engine 7 is detected based on the output of the engine sensor 98 that detects the output rotational speed of the engine 7. Based on the output of the stop sensor 99 provided on the guide plate 55 and the output of the timer (not shown) provided on the ECU 66 so as to detect, the main transmission lever 40 is held at the engine stop position 55d for a predetermined time or more. Engine stop control is performed when an operation (hereinafter referred to as a predetermined operation of the main transmission lever 40) is detected.

  In the second selected state, when the engine sensor 98 detects the operation of the engine 7 and the clutch sensor 100 that detects the on / off state of the planting clutch 23 detects the engaged state of the planting clutch 23, It is detected that the vehicle is in a working state, and engine stop control is performed when a predetermined operation of the main transmission lever 40 is detected based on the outputs of the stop sensor 99 and the timer in this detection state.

  In the third selection state, when the engine sensor 98 detects the operation of the engine 7 and detects that the steering angle of the front wheel 13 is equal to or smaller than the set angle based on the output of the rudder angle sensor 86, the vehicle turns. It is determined that the engine is not in a state, and in this state, engine stop control is performed when a predetermined operation of the main transmission lever 40 is detected based on the output of the stop sensor 99 and the timer. On the other hand, when it is detected that the steering angle of the front wheels 13 exceeds the set angle based on the output of the rudder angle sensor 86, it is determined that the vehicle is in a coasting turning state, and in this state, the output of the stop sensor 99 and the timer is output. Even if a predetermined operation of the main speed change lever 40 is detected based on this, the engine stop control is not performed.

  In each selected state, after the engine is stopped by the engine stop control, the engine start control is performed when the separation of the main shift lever 40 from the engine stop position 55d is detected based on the output of the stop sensor 99.

  In the deselected state, the engine stop control is performed even if a predetermined operation of the main transmission lever 40 is detected in a state where the operation of the engine 7 or the planting work state is detected based on the output of the engine sensor 98 or the clutch sensor 100. Absent.

  The engine sensor 98 employs an electromagnetic pickup type rotation sensor. Limit switches are employed for the stop sensor 99 and the clutch sensor 100.

  As shown in FIG. 14, in the engine stop control, the engine control unit 66F first detects the predetermined operation of the main transmission lever 40, and first, the raising / lowering of the seedling planting device 4 held by the elevation control unit 66A. Various information such as information on the power of the work operation control means 66B and information on the continuity of work power held by the work operation control means 66B and setting information by various selection switches 88 to 90, 97, etc. are read and stored in the EEPROM [Step # 1. ].

  Next, it is determined whether or not an engine stop condition is satisfied [steps # 2 to # 4]. Specifically, based on the output of the engine sensor 98, it is determined whether or not the output rotational speed of the engine 7 is equal to or lower than a set rotational speed (for example, idling rotational speed) [Step # 2], and the voltage for detecting the voltage of the battery 76 It is determined whether or not the voltage of the battery 76 is equal to or higher than a set value based on the output of the detector 101 (see FIG. 12) [Step # 3], and the temperature of the engine cooling water is set to a set value (based on the output of the water temperature sensor 102). It is determined whether or not the angle is, for example, 55 degrees (step # 4). The engine stop condition is satisfied only when the output speed of the engine 7 is equal to or lower than the set speed, the voltage of the battery 76 is equal to or higher than the set value, and the temperature of the engine coolant is equal to or higher than the set value. Otherwise, it is determined that the conditions for stopping the engine are not satisfied.

  And when the conditions for engine stop are satisfied, the state immediately before starting the engine stop control is based on the various information read in step # 1, and the working state in which the seedling planting device 4 and the fertilizer application device 6 are operated. [Step # 5].

  If it is in the working state, the blower stop control and the clutch disengagement control are instructed to the work operation control means 66B to stop the blower 35 and switch the planting clutch 23 and the fertilizer clutch 74 to the disengaged state [Step # 6, # 7]. Also, stop the control operation for work by instructing the lift control means 66A, the rolling control means 66D, etc. to stop the control operation for work such as automatic lift control and horizontal control that was executed immediately before the start of engine stop control. [Step # 8]. Thereafter, the igniter relay 96 is energized to switch the igniter relay 96 to an open state in which the energization from the battery 76 to the igniter 95 is stopped, thereby stopping the engine 7 and ending the engine stop control [step # 9].

  On the other hand, if the engine is not in the working state, the process immediately proceeds to step # 9 to stop the engine 7 and finish the engine stop control.

  If the conditions for stopping the engine are not satisfied in steps # 2 to # 4, it is determined whether or not the main transmission lever 40 is at the engine stop position 55d based on the output of the stop sensor 99 [step # 10]. If the engine stop position is 55d, the process returns to step # 2 to determine whether or not the engine stop condition is satisfied. If it is not the engine stop position 55d, it is determined that the main shift lever 40 has been detached from the engine stop position 55d, and the engine stop control is terminated.

  That is, when the first selection state is selected, for example, when the planting operation is interrupted for seedling joining to the seedling mounting table 26 or fertilizer supply to the hopper 34, the planting operation is interrupted. The predetermined operation of the main transmission lever 40 described above is performed on the main transmission lever 40 located at the neutral position 55a by the operation to the neutral position 55a of the main transmission lever 40 or the depression operation of the brake pedal 42 to the depression limit position. Thus, the engine 7 can be automatically stopped.

  In addition, for example, when it becomes necessary to perform auxiliary work such as replenishment of spare seedlings to the spare seedling placement device 46 performed at the heel during the planting work, the planting work is interrupted and traveling to the heel is performed. After the operation, the main transmission lever 40 located at the neutral position 55a is operated by the operation to the neutral position 55a of the main transmission lever 40 or the operation to the depression limit position of the brake pedal 42, which is performed for stopping the running at the shore. On the other hand, the engine 7 can be automatically stopped by performing the predetermined operation of the main transmission lever 40 described above.

  As a result, when the planting operation is interrupted and auxiliary operations such as seedling joining and fertilizer supply are performed on the spot, or when the planting operation is interrupted and moved to the edge, the spare seedling is placed on the preliminary seedling placement device 46. When performing auxiliary work such as replenishment, or when temporarily stopped by traveling outside the field, it is possible to prevent wasteful fuel consumption due to the operation of the engine 7 between them, The fuel consumption can be improved.

  When the second selection state is selected, the engine 7 is operated by the predetermined operation of the main transmission lever 40 only when the planting operation is interrupted and auxiliary operations such as seedling joining and fertilizer replenishment performed on the spot are performed. Can be stopped. As a result, wasteful fuel consumption due to the operation of the engine 7 can be prevented while assisting operations such as seedling and fertilizer supply are performed, and fuel consumption can be improved. Further, in other work states where it is not necessary to perform auxiliary work such as seedling joining or fertilizer replenishment, a reduction in work efficiency due to the engine 7 being stopped by a predetermined operation of the main transmission lever 40 described above can be avoided. Can do.

  In addition, for example, even when a predetermined operation of the main transmission lever 40 is erroneously performed due to an unexpected contact with the main transmission lever 40 or the like at the time of temporary stop in traveling traveling without planting, Since the engine 7 does not stop based on a predetermined operation of the main speed change lever 40, it is possible to avoid the possibility that the engine 7 will stop unexpectedly when temporarily stopped during traveling.

  When the third selection state is selected, when planting work is interrupted and auxiliary work such as seedling splicing or fertilizer replenishment performed on the spot is performed, the planting work is interrupted and moved to the heel, and then by the heel turning When performing auxiliary work such as supplementary seedling supply to the preliminary seedling placement device 46 performed in a state where the vehicle is parked forward without being laid down, or when temporarily stopped by traveling traveling outside the field, etc. However, wasteful fuel consumption due to the operation of the engine 7 can be prevented, and fuel consumption can be improved.

  In the third selected state, as in the riding rice transplanter exemplified in the present embodiment, a pair of left and right spare seedling placement devices 46 are provided at the front portion of the traveling vehicle body 1, and left and right spare seedling placement devices are provided. This is particularly effective in the case where the spare seedling supply to 46 is configured to be performed from the front of the vehicle body. In such a rice paddy transplanter, the normal seedling supply to the left and right preliminary seedling placement devices 46 is normally performed. It is possible to avoid the possibility that the engine 7 may stop unexpectedly due to an erroneous operation of the main speed change lever 40 in a state where the main shift lever 40 is erroneously operated in a state where the main shift lever 40 is in a horizontal state in a state where the travel is stopped in the middle of the corner turning.

  In addition, when the engine 7 is automatically stopped by the engine stop control in the working state, the seedling planting device 4 and the fertilizer application device 6 are also automatically stopped, so that the blower 35 is operated while the engine 7 is stopped. It is possible to prevent the occurrence of inconvenience such as battery exhaustion.

  In addition, even if the main speed change lever 40 is operated to the engine stop position 55d, the engine 7 is not automatically stopped if the above-mentioned conditions for engine stop are not satisfied. If the temperature is less than or less than the set value, the risk of inconvenience such as troublesome restarting of the engine 7 due to the automatic stop of the engine 7 can be avoided. .

  As shown in FIG. 15, in the engine start control, the engine control unit 66F detects various types of data stored in the EEPROM immediately before the start of the engine stop control as the main shift lever 40 is detected to be detached from the engine stop position 55d. Information is read [Step # 1], and it is determined whether or not the state immediately before the engine stop control is started is a working state based on the various pieces of read information [Step # 2].

  If it is in the working state, first, the work operation control means 66B is instructed to execute the blower start control described above to operate the blower 35 [Step # 3], and then the work operation control means 66B is described above. The execution of clutch engagement control is commanded to switch the planting clutch 23 and the fertilizer application clutch 74 to the engaged state [step # 4]. In addition, the control operation for work such as automatic lifting control or horizontal control, which has been executed immediately before the engine stop control is started, is commanded to the lifting control means 66A, the rolling control means 66D, etc., and the work control action is resumed. [Step # 5].

  Next, the energization of the engine 7 is permitted by stopping the energization of the igniter relay 96 and switching the igniter relay 96 to a closed state in which the igniter 95 is energized from the battery 76 [step # 6]. During the set time, the starter relay 94 is energized to switch to a closed state in which the starter relay 94 is energized from the battery 76 to the starter 93, thereby operating the starter 93 by energizing the starter 93 from the battery 76 bypassing the main switch 91. Then, the engine 7 is started [steps # 7 to # 9]. Based on the output of the engine sensor 98, it is determined whether or not the output rotational speed of the engine 7 is equal to or higher than the set rotational speed [Step # 10]. Then, the engine start control is finished. If it is not equal to or higher than the set rotational speed, it is determined that the engine 7 has not started, and the routine returns to step # 7, where the starter 93 is operated again to start the engine 7.

  On the other hand, if it is not in the working state in step # 2, the process immediately proceeds to step # 6, the control operation of steps # 6 to 10 is performed to start the engine 7, and the engine start control is terminated.

  That is, after the engine is stopped by the engine stop control, if the restart operation for restarting the engine 7 by moving the main transmission lever 40 from the engine stop position 55d to the neutral position 55a is performed, the state before the engine stop by the engine stop control is changed. When it is in the working state, the operation state of the seedling planting device 4 and the fertilizer application device 6 can be automatically reproduced in the same state as the operation state before the engine stop, along with the restarting operation. Thus, by operating the main speed change lever 40 from the neutral position 55a to the forward speed change path 55b after the engine 7 is restarted, the planting work can be quickly restarted in the same operating state as before the engine is stopped.

  As described above, since the starter relay 94 is provided in parallel with the main switch 91 between the battery 76 and the brake switch 92, the brake 25 that has been operated by depressing the brake pedal 42 to the limit position is depressed. Only when the main shift lever 40 is disengaged from the engine stop position 55d in the braking state, the energization from the battery 76 to the starter 93 via the starter relay 94 is allowed and is based on the operation of the main shift lever 40. The engine 7 can be started by operating the starter 93.

  Even when the starter relay 94 cannot be started due to energization of the starter 93 from the battery 76 via the starter relay 94 due to a failure of the starter relay 94, the battery 76 based on the operation of the main switch 91 Since the engine 7 can be started by energizing the starter 93, the engine 7 can be started by operating the main switch 91.

  The engine control unit 66F always monitors the output of the water temperature sensor 102 after the engine is stopped by the engine stop control, and the temperature of the engine cooling water exceeds the set upper limit temperature (for example, 110 degrees) based on the output of the water temperature sensor 102. Is detected, the engine 7 is forcibly restarted by performing the engine start control described above even when the main transmission lever 40 is in the engine stop position 55d. A cooling fan (not shown) operated by power is operated to cool the engine 7 and the engine coolant.

  Incidentally, as the switching of the selection state relating to the execution of the engine stop control described above, the selection is made with at least one of the first selection state, the second selection state, and the third selection state based on the operation of the selection switch 97. You may comprise so that it may switch to a cancellation | release state. The order of the selection state that is switched every time the selection switch 97 is pressed can be variously changed.

  Further, as a condition for enabling execution of engine stop control, an output of a spare seedling supply detection means (not shown) for detecting that the corresponding left and right spare seedling placement devices 46 are in the above-described spare seedling supply state is used. When it is detected that at least one of the left and right spare seedling placement devices 46 is in the spare seedling replenishment state, based on the output of the seedling breakage detection means (not shown) provided in the seedling planting device 4 When the seedling planting device 4 detects the lack of seedling, when the fertilizer device 6 detects the lack of fertilizer based on the output of the fertilizer shortage detection means (not shown) provided in the fertilizer application device 6, or fertilization For example, when fertilizer clogging is detected in the fertilizer application device 6 based on the output of the fertilizer clogging detection means (not shown) provided in the device 6.

  Regarding the detection of the planting work state in the second selected state, the output of the sub-shift lever sensor (not shown) for detecting the operation of the sub-shift lever 41 to the low speed position for work travel, the center by the float sensor 69 Either one or a plurality of detections such as ground contact detection of the float 28, detection of the left or right drawing marker 78 reaching the working posture by the left and right marker sensors 80, or detection of straight travel of the front wheels 13 by the rudder angle sensor 86. You may comprise so that a planting operation state may be detected based on it.

  Regarding the detection of the turning state in the third selection state, the output of the side clutch sensor (not shown) for detecting the disengagement state of the corresponding left and right side clutch 19, the floating detection of the center float 28 by the float sensor 69, Or you may comprise so that a planting operation state may be detected based on any one or more, such as execution of the clutch turning control by the turning control means 66E. Further, when the turning control means 66E performs the turning angle integration process for integrating the turning angle of the vehicle body during the cornering turning, the planting operation state may be detected based on the execution of the turning angle integration process. Good.

  As shown in FIG. 8, in the guide groove 55A of the guide plate 55 that guides the main speed change lever 40, the forward speed change path 55b used at the time of planting is connected to the left end portion of the forward / backward changeover path 55a. By setting the left end portion of the auxiliary guide portion 55Ab extending leftward from the left end of the advance switching path 55a to the engine stop position 55d, the operation time required for the operation of the main transmission lever 40 from the forward shift path 55b to the engine stop position 55d This is intended to shorten the time.

  On the other hand, when the main speed change lever 40 is operated from the reverse speed change path 55c to the forward speed change path 55b along the forward / reverse switching path 55a, the engine stop position 55d is located on the extension line of the operation. An erroneous operation of the lever 40 to the engine stop position 55d is likely to occur. Therefore, other than when the vehicle body is moved too close to the heel and moved backward when the vehicle body is stopped forward with respect to the heel to perform auxiliary work such as replenishment of the spare seedling placement device 46 from the heel in front of the body In some cases, the engine stop control is executed by the operation from the reverse shift path 55c of the main shift lever 40 to the engine stop position 55d, which is rarely performed regardless of the driver's intention. As a result, in planting work that repeats forward and backward movement, which is often performed at a deformed part of the deformed field, the work efficiency is reduced due to the engine 7 being unnecessarily stopped when switching from reverse to forward. It becomes easy to invite.

  Therefore, as shown in FIG. 12 and FIG. 16, in this riding rice transplanter, the operability of the main shift lever 40 for performing a predetermined operation for starting the engine stop control is changed from the forward shift path 55b to the reverse shift path 55c. The engine control means 66F is provided with the operability difference means A for preventing the above-mentioned inconvenience by making the difference from the above.

  The operability difference control by the operability difference means A will be described in detail based on the flowchart shown in FIG. 16. The operability difference means A detects the output of the stop sensor 99 and the operation position of the main transmission lever 40 in the front-rear direction. The output of the shift lever sensor 111 is constantly monitored [Step # 1], and when the operation of the main shift lever 40 to the engine stop position 55d is detected based on the output of the stop sensor 99, the output of the shift lever sensor 111 is used. Thus, it is determined whether the operation of the main shift lever 40 to the engine stop position 55d is an operation from the forward shift path 55b or an operation from the reverse shift path 55c [steps # 2 and # 3].

  If the operation is from the forward shift path 55b, the predetermined time for holding the main transmission lever 40 at the engine stop position 55d is set as the first predetermined time (for example, 0.5 seconds) [step # 4], and the stop sensor 99 and Based on the output of the timer, it is determined whether or not the main transmission lever 40 is held at the engine stop position 55d until the first predetermined time has elapsed [steps # 5 and # 6]. If held, the engine shifts to the engine stop control as the first predetermined time elapses [step # 7], and if not held, the process returns to step # 1.

  On the other hand, in the case of an operation from the reverse shift path 55c, the predetermined time for holding the main transmission lever 40 at the engine stop position 55d is set to a second predetermined time (for example, 2 seconds) longer than the first predetermined time [Step # 8]. Based on the outputs of the stop sensor 99 and the timer, it is determined whether or not the main transmission lever 40 is held at the engine stop position 55d until the second predetermined time has elapsed [steps # 9 and # 10]. If held, the engine shifts to engine stop control as the second predetermined time elapses [step # 11]. If not held, the process returns to step # 1.

  That is, the time required for the predetermined operation of the main speed change lever 40 from the reverse travel state to the engine stop control is longer than the time required for the main operation of the main speed change lever 40 to shift from the forward movement state to the engine stop control. Thus, while preventing the above-mentioned inconvenience, the planting operation is interrupted to perform auxiliary work such as seedling and fertilizer replenishment, or the vehicle body is stopped forward with respect to the heel. When performing a predetermined operation of the main shift lever 40 from the forward state, which is an operation that is always required when performing an auxiliary operation such as supplementing a preliminary seedling to the preliminary seedling placement device 46 from the heel in front of the vehicle body Thus, it is possible to make the operability better than a predetermined operation of the main transmission lever 40 from the reverse state, which is rarely performed, and to improve the working efficiency.

  The shift lever sensor 111 employs a rotary potentiometer.

    [Another embodiment]

[1] The work vehicle may be a seeder, a tractor, a combine, or a backhoe. Further, a diesel engine may be adopted as the engine 7. In the case where a diesel engine is employed, it is conceivable that the engine 7 is stopped by operating a fuel shut-off device such as a fuel cut solenoid that shuts off the fuel supply to the diesel engine.

[2] The forward / reverse switching operation tool 40 may be a main transmission pedal that enables a shift operation and a forward / reverse switching operation of the main transmission 8. Further, in a work vehicle including a forward / reverse switching device dedicated to forward / reverse switching, a dedicated operation lever or operation pedal that enables forward / reverse switching operation of the forward / reverse switching device may be used.

[3] The predetermined operation of the operation tool 40 for forward / reverse switching may be a holding operation for a predetermined time at a neutral position (forward / reverse switching path 55a) which is an example of the predetermined position P of the operation tool 40. In this case, the operation tool 40 is held in the neutral position (forward / reverse switching path 55a) by the operation from the reverse transmission path 55c for a predetermined time which is held in the neutral position (forward / reverse switching path 55a) by the operation from the forward transmission path 55b. The operability different means A is configured by lengthening the predetermined time to be operated, whereby the operability when the engine 7 is stopped by the predetermined operation of the operation tool 40 is more backward than the forward shift path 55b. You may comprise so that it may become better than 55c.

[4] As shown in FIG. 17, when the forward / reverse switching operation tool 40 is the main speed change lever 40, a first position formed on the left side of the forward speed change path 55 b along the forward speed change path 55 b. The first auxiliary area 55e and the second auxiliary area 55f formed along the reverse speed change path 55c at a position deviated to the right of the reverse speed change path 55c are set as predetermined positions P, and the first auxiliary area 55e of the main speed change lever 40 is set. The first detection means 103 for detecting the operation to the left is opposed to the action of the pair of first compression springs 104 in accordance with the operation from the forward shift path 55b of the main shift lever 40 to the left first auxiliary region 55e. A first guide member 105 that is slid toward the left side, and a first mitt switch 106 that detects a left side slidable displacement of the first guide member 105, and the second auxiliary of the main transmission lever 40. Region 5 The second detection means 107 that detects the operation to f is operated against the action of the pair of second compression springs 108 in accordance with the operation from the reverse transmission path 55c of the main transmission lever 40 to the second auxiliary region 55f on the right side. A second guide member 109 that slides to the right and a second mitt switch 110 that detects the sliding displacement of the second guide member 109 to the right are provided, and a predetermined operation of the main transmission lever 40 is performed. The operation of the main shift lever 40 to the first auxiliary area 55e or the second auxiliary area 55f and the subsequent operation to the neutral position (forward / reverse switching path 55a) may be performed.

  In this case, the pair of first compression springs 104 serve as blocking means B that mechanically inhibits the operation of the main transmission lever 40 to the first auxiliary region 55e (predetermined position P), and the pair of second compression springs 104 The compression spring 108 is an inhibiting means B that mechanically inhibits the operation of the main transmission lever 40 to the second auxiliary region 55f (predetermined position P), and each second compression spring 108 is more than the spring force of each first compression spring 104. The operability difference is set such that the degree of inhibition by the inhibiting means B in the second auxiliary region 55f is larger than the degree of inhibition by the inhibiting means B in the first auxiliary region 55e by increasing the spring force of The means A is configured so that the operability when the engine 7 is stopped by a predetermined operation of the main transmission lever 40 is improved from the forward transmission path 55b than from the reverse transmission path 55c. May be.

  Although not shown in the drawings, the second mitt switch 110 has a main shift that is longer than the operation distance required until the first mitt switch 106 detects the operation of the main shift lever 40 to the first auxiliary area 55e (predetermined position P). By configuring so that the operation distance required until the operation of the lever 40 to the second auxiliary region 55f (predetermined position P) is detected becomes longer than the degree of inhibition by the inhibiting means B in the first auxiliary region 55e. The operability difference means A is configured by setting the degree of inhibition by the inhibition means B in the second auxiliary region 55f to be large, and thereby, when the engine 7 is stopped by a predetermined operation of the main transmission lever 40. The operability may be configured such that the forward transmission path 55b is better than the reverse transmission path 55c.

  It should be noted that the engine 7 can be started with these configurations by operating a start-only switch (not shown) such as an alternate switch.

[5] As shown in FIG. 18, when the forward / reverse switching operation tool 40 is the main speed change lever 40, the auxiliary guide portion extends leftward or rightward at the left and right ends of the forward / reverse switching path 55 a. 55Ab is connected and the left end or the right end of the auxiliary guide portion 55Ab is set to the engine stop position 55d as the predetermined position P, and the left and right engine stop positions corresponding to the left and right of the main transmission lever 40 are set on the guide plate 55. A pair of left and right engine detent mechanisms 63 that mechanically obstruct the operation to the position 55d and enable the main transmission lever 40 to be held at the corresponding left and right engine stop positions 55d are provided as the inhibiting means B. Thus, a predetermined operation from the forward shift path 55b of the main shift lever 40 is an operation to the engine stop position 55d on the left side close to the forward shift path 55b. A predetermined operation from the reverse speed path 55c of over 40 may be operated to the right of the engine stop position 55d closer to the reverse shift path 55c.

  In this case, the degree of inhibition by the right inhibition means B corresponding to the right engine stop position 55d is greater than the degree of inhibition by the left inhibition means B corresponding to the left engine stop position 55d. The operability difference means A is set to configure the main transmission lever 40 in a predetermined operation while suppressing the main transmission lever 40 from entering the left and right engine stop positions 55d during the forward / reverse switching operation. You may comprise so that the operativity at the time of stopping the engine 7 may become better from the forward transmission path 55b than from the reverse transmission path 55c.

[6] As shown in FIG. 19, when the forward / reverse switching operation tool 40 is the main speed change lever 40, the auxiliary guide portion extends leftward or rightward at the left and right ends of the forward / reverse switching path 55 a. 55Ab is connected and these auxiliary guide portions 55Ab are set to the engine stop position 55d as the predetermined position P, and a predetermined operation from the forward shift path 55b of the main shift lever 40 is applied to the forward shift path 55b. The holding operation for a predetermined time at the near left engine stop position 55d, and the predetermined operation from the reverse shift path 55c of the main transmission lever 40 for a predetermined time at the right engine stop position 55d near the reverse shift path 55c. It is good also as holding operation.

  In this case, the predetermined time for holding the main transmission lever 40 at the right engine stop position 55d is set longer than the predetermined time for holding the main transmission lever 40 at the left engine stop position 55d. The operability different means A is configured so that the operability when the engine 7 is stopped by a predetermined operation of the main shift lever 40 is improved from the forward shift path 55b than from the reverse shift path 55c. You may comprise.

  It should be noted that the engine 7 can be started in this configuration by operating a start-only switch (not shown) such as an alternate switch.

[7] As shown in FIG. 20, when the forward / reverse switching operation tool 40 is the main speed change lever 40, the auxiliary guide portion 55Ab extends forward or backward at the left and right ends of the forward / reverse switching path 55a. Are connected to each other, and these auxiliary guide portions 55Ab are set to the engine stop position 55d as the predetermined position P, and a predetermined operation from the forward transmission path 55b of the main transmission lever 40 is performed by extending the forward transmission path 55b. The left engine stop position 55d positioned on the line is held for a predetermined time, and the predetermined operation from the reverse shift path 55c of the main shift lever 40 is performed on the right engine positioned on the extension line of the reverse shift path 55c. It may be a holding operation for a predetermined time at the stop position 55d.

  In this case, the predetermined time for holding the main transmission lever 40 at the right engine stop position 55d is set longer than the predetermined time for holding the main transmission lever 40 at the left engine stop position 55d. The operability different means A is configured so that the operability when the engine 7 is stopped by a predetermined operation of the main shift lever 40 is improved from the forward shift path 55b than from the reverse shift path 55c. You may comprise.

  It should be noted that the engine 7 can be started in this configuration by operating a start-only switch (not shown) such as an alternate switch.

[8] As shown in FIG. 21, when the forward / reverse switching operation tool 40 is used as the main speed change lever 40, the auxiliary guide portion 55Ab is connected and formed so as to extend rightward from the right end of the forward / reverse switching path 55a. In addition, the auxiliary guide portion 55Ab may be set to the engine stop position 55d as the predetermined position P, and the predetermined operation of the main transmission lever 40 may be a holding operation for a predetermined time at the engine stop position 55d.

  In this case, contrary to the above-described embodiment, when the main speed change lever 40 is operated from the forward speed change path 55b to the engine stop position 55d, a predetermined time required for holding at the engine stop position 55d is When the lever 40 is operated from the reverse speed change path 55c to the engine stop position 55d, the operability different means A is configured by setting the lever 40 so as to be longer than a predetermined time required for holding at the engine stop position 55d. It is also possible to suppress the possibility that the main transmission lever 40 enters the engine stop position 55d and the engine 7 is stopped during the switching operation.

  It should be noted that the engine 7 can be started in this configuration by operating a start-only switch (not shown) such as an alternate switch.

  Although not shown, in this configuration, the guide plate 55 mechanically obstructs the operation of the main transmission lever 40 to the engine stop position 55d and holds the main transmission lever 40 at the engine stop position 55d. A detent mechanism 63 for stopping the engine may be provided.

[9] Although not shown, the engine control means 66F may be provided with a selection means for selecting execution of the engine stop control so that the selection means performs the engine stop selection control described below.

  In the engine stop selection control, the selection means always monitors the output of the stop sensor 99 and the output of the shift lever sensor 111 that detects the operation position of the main shift lever 40 in the front-rear direction, and based on the output of the stop sensor 99 When operation of the shift lever 40 to the engine stop position 55d is detected, based on the output of the shift lever sensor 111, whether the operation of the main shift lever 40 to the engine stop position 55d is from the forward shift path 55b or reverse shift It is determined whether the operation is from the path 55c.

  If the operation is from the forward shift path 55b, the operation proceeds to the engine stop control. If the operation is from the reverse shift path 55c, the output from the stop sensor 99 and the output from the shift lever sensor 111 is performed without proceeding to the engine stop control. Return to the monitoring state.

  That is, engine stop control is performed when the main transmission lever 40 is positioned at the engine stop position 55d by an operation from the forward transmission path 55b, and the main transmission lever 40 is positioned at the engine stop position 55d by an operation from the reverse transmission path 55c. In this case, the engine stop control is not performed.

  The notification control structure for a work vehicle according to the present invention can be applied to a seeder, a tractor, a combine, or a backhoe equipped with an engine and equipped with an operation tool for switching between forward and reverse.

7 Engine 40 Forward / reverse switching operation tool (shifting operation tool)
55Aa Operation path 55a Neutral position (forward / reverse switching path)
55b Forward shift path 55c Reverse shift path A Operability difference means B Inhibition means P Predetermined position

Claims (6)

In the engine stop operation structure of the work vehicle configured to stop the engine based on a predetermined operation of the operation tool for forward / reverse switching,
An engine stop operation structure for a work vehicle, comprising operability different means for changing operability when the engine is stopped by a predetermined operation of the operation tool between a forward state and a reverse state.   2. The configuration according to claim 1, wherein the operability different means is configured such that the time required for the predetermined operation of the operation tool from the reverse state is longer than the time required for the predetermined operation of the operation tool from the forward movement state. The engine stop operation structure of the described work vehicle. The predetermined operation of the operation tool is a holding operation for a predetermined time at a predetermined position of the operation tool,
The engine stop operation structure for a work vehicle according to claim 1 or 2, wherein the operability different means is configured by changing the predetermined time. The predetermined operation of the operation tool is an operation to a predetermined position outside the normal operation path of the operation tool,
An inhibiting means for mechanically inhibiting the operation of the operation tool to a predetermined position is provided,
The engine stop operation structure for a work vehicle according to claim 1 or 2, wherein the operability difference means is configured by varying the degree of inhibition by the inhibition means. The operation tool is a shift operation tool that serves both as a forward / reverse switching and a gear shift,
The engine stop operation structure for a work vehicle according to any one of claims 1 to 4, wherein the predetermined operation of the operation tool is an operation for performing an operation to at least a predetermined position connected to a neutral position of the speed change operation tool. . The operation tool is a shift operation tool that serves both as a forward / reverse switching and a gear shift,
The operation path of the shift operation tool is extended in the front-rear direction from the forward / reverse switching path in the left / right direction, the forward shift path extending from the one end of the forward / reverse switching path and the other end of the forward / backward switching path. And a reverse speed change path to be formed,
The predetermined operation of the shift operation tool is a holding operation for a predetermined time at a predetermined position connected to the left and right side ends of the forward / reverse switching path of the shift operation tool,
From the shift path farther from the predetermined position than the predetermined time when the shift operation tool is operated from the shift path closer to the predetermined position of the forward shift path and the reverse shift path to the predetermined position. The engine stop operation structure for a work vehicle according to claim 1, wherein the operability different means is configured by lengthening the predetermined time when operated to the predetermined position.

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