JP2011157883A - Working vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a working vehicle with fuel tanks on the right and left sides, enabling to select fuel from the right or left fuel tank without the need for a driver to get off the vehicle. <P>SOLUTION: The working vehicle includes the independent fuel tanks 50 provided on the right and left sides of a travelling body, right and left electric pumps 62 for supplying fuel from the right and left fuel tanks 50 to an engine 19 via right and left fuel supply passages 58, 59 in a right-and-left individual manner, and an operation switch 63 artificially operable for actuating the right and left electric pumps 62 into the condition that the left electric pump 62 is stopped and the right electric pump 62 is actuated or into the condition that the right electric pump 62 is stopped and the left electric pump 62 is actuated. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a work vehicle including an electric pump in a fuel supply path for supplying fuel to an engine from a fuel tank provided in a traveling machine body.

  2. Description of the Related Art A work vehicle is known that includes a fuel tank in a traveling machine body and an electric pump (electric fuel pump) in a fuel supply path that connects the fuel tank and an engine carburetor (see Patent Document 1).

  The above work vehicle supplies the fuel in one fuel tank to the engine via an electric pump, so there is no problem in the fuel supply system, but recently, there are fuel tanks provided on the left and right sides of the traveling machine body. It is known (see Patent Document 2).

  Further, as a conventional technique, in which fuel tanks are separately provided on the left and right sides of the traveling body, the fuel supply path and the fuel return path of the right fuel tank and the left fuel tank are connected to the switching valve, and the switching valve It is known that the fuel in the right fuel tank or the left fuel tank is supplied to the engine via a pump by switching.

Japanese Patent Laid-Open No. 11-4615 JP 2007-196862 A

  In the case where the fuel tanks are provided on the left and right sides and the fuel in the left and right fuel tanks is switched by the switching valve as described above, when the fuel in one fuel tank becomes low or the fuel in one fuel tank runs out. In such a case, the driver has to get off each time and switch the switching valve.

  An object of the present invention is to make it possible to switch fuel in left and right fuel tanks in a work vehicle having left and right fuel tanks without having to get off each time as in the prior art.

[Configuration of the first invention]
The first invention includes independent fuel tanks on the left and right sides of the traveling aircraft body, a right fuel supply path for supplying fuel from the right fuel tank to the engine and a right electric pump, and the left fuel tank to the engine. A state in which a left fuel supply path and a left electric pump for supplying fuel are provided, the left electric pump is stopped and the right electric pump is operated; and the right electric pump is stopped and the left electric pump is stopped. An artificially operable operation switch for operating the right and left electric pumps is provided in a state in which the pump is operated.

[Effects of the first invention]
According to the configuration of the first aspect of the invention, since the electric pumps are separately provided in the supply paths of the left and right fuel tanks and the operation switches that can be operated manually to operate the right and left electric pumps are provided. By placing the operation switch near the driver's seat, the fuel tank that supplies fuel can be switched while seated in the driver's seat, improving workability compared to conventional fuel supply systems. . In addition, since the fuel systems that are independent on the left and right are constructed, it is possible to lay out the filter, the pump, and the hose connecting them in an optimal position.

[Configuration of the second invention]
According to a second invention, in the configuration of the first invention, the left and right electric pumps are respectively disposed below the left and right fuel tanks.

[Operation and effect of the second invention]
According to the second invention, the left and right electric pumps are arranged below the left and right fuel tanks, respectively, so that the fuel reaches the pump by its own weight, so that it is possible to supply the fuel even with a pump having a weak suction force. An inexpensive and simple pump can be used. In addition, since the electric pump is disposed under the fuel tank away from the engine, the electric pump is not easily affected by the hot air of the engine, and the temperature in the electric pump and the fuel supply path near the electric pump connected to the electric pump are reduced. Since the temperature of the fuel does not increase significantly, vapor lock does not occur, and it is possible to avoid a situation in which it is difficult to stop or start the engine.

[Configuration of the third invention]
According to a third invention, in the configuration of the second invention, a filter is disposed below the fuel tank, the electric pump is disposed below the filter, the fuel tank and the filter, and the filter and the electric motor. Pumps are connected to each other through the fuel supply path.

[Operation and effect of the third invention]
According to the third aspect of the present invention, when the filter is disposed below the fuel tank and the electric pump is disposed below the filter, when the fuel is fed from the fuel tank through the filter to the electric pump by its own weight with the difference in height, The tank to the filter and the electric pump can be connected by a short fuel supply path.

[Configuration of the fourth invention]
According to a fourth aspect, in the configuration of the third aspect, the inlet port of the filter is on the upper side, the outlet port is on the lower side, and the filter is disposed obliquely with respect to the vertical line.

[Effects of the fourth invention]
When the filter is arranged vertically, the dust is scattered uniformly in each part inside the filter, the dust adheres to all parts inside the last filter, and the fuel passes through all parts inside the filter. It may be impossible to do so.
According to the fourth aspect of the present invention, the filter is disposed obliquely below the fuel tank, so that dust is easily collected at a specific location (low location) inside the filter, and dust is collected at locations other than the specific location. Because it becomes difficult, it is possible to secure the passage of fuel in the place where dust inside the filter is difficult to collect, and it is possible to reduce the passage resistance of the fuel as a whole of the filter, making it easy to feed the fuel with the height difference and due to its own weight Fuel supply is further improved.

If the filter is arranged in the horizontal direction, dust is likely to collect at a specific location (low location) inside the filter, and it is advantageous in that it is difficult to collect dust at locations other than this specific location. It is disadvantageous in terms of sending fuel.
According to the fourth aspect of the present invention, the filter is disposed obliquely below the fuel tank, so that dust is easily collected at a specific location (low location) inside the filter, and dust is collected at locations other than the specific location. While ensuring the advantage of being difficult, it becomes easier to feed the fuel at a height difference, and the fuel supply performance by its own weight is further improved.

1 is an overall side view of a riding mower. 1 is an overall plan view of a riding mower. It is a principal part side view of the rear part of a riding type mower. It is a principal part side view which shows the opening-and-closing structure of the baseplate of an engine room. It is a principal part top view which shows the opening / closing structure of the bottom plate of an engine room. (A) is a side view of a fuel tank, (b) is a top view of a fuel tank. It is a block diagram which shows a fuel system. (A) is a side view of the fuel tank of another embodiment, (b) is the same plan view. It is a side view of the fuel tank of another embodiment. It is a rear view which shows the fuel tank which shows another embodiment, the tank for transpiration | evaporation gas separation, a shut-off valve, 2 way valve | bulb, and the electric motor for recirculation | reflux.

  Hereinafter, an embodiment in which the present invention is applied to a riding mower as an example of a work vehicle will be described. FIG. 1 is an overall side view of a riding mower, and FIG. 2 is an overall plan view. As shown in FIG. 1 and FIG. 2, the riding mower illustrated in this embodiment includes a link mechanism 4 between a pair of left and right front wheels 2 and a pair of left and right rear wheels 3 in the traveling machine body 1. By arranging the mower 5 to be movable up and down, it is configured in a mid-mount type.

  The traveling machine body 1 is provided with a front frame 6 made of a square pipe material or the like on the front side thereof. The front frame 6 supports the link mechanism 4, and the left and right front wheels 2 are arranged at the left and right end portions of the front end portion so as to be capable of following and steering around the vertical axis. The link mechanism 4 moves the mower 5 up and down in parallel by the operation of a hydraulic cylinder (not shown).

  The front frame 6 is provided with a boarding step 8 made of sheet metal so as to cover substantially the whole from above. The boarding step 8 has a rubber mat (not shown) laid on the surface thereof, a brake pedal 9 urged to return to the non-braking position at the center of the front, and a brake against the urging. A lock pedal 10 is provided that enables the pedal 9 to be locked and held at the braking position. A driver's seat 11 is disposed on the upper rear side of the boarding step 8 so that the position can be adjusted. A fender 12 and a shift lever 13 are respectively provided on the left and right sides of the driver seat 11. An arch-shaped lops frame 14 is provided behind the driver seat 11. That is, in this riding mower, the boarding operation unit 15 is formed on the front side of the traveling machine body 1.

  As shown in FIG. 3, a rear frame 16 connected to the rear end portion of the front frame 6 is disposed at the rear portion of the traveling machine body 1. The rear frame 16 includes a pair of left and right side members 17 made of a sheet metal material, a mounting table 18 serving as a bottom plate supported by the left and right side members 17, and the like. An air-cooled gasoline engine 19 is mounted on the mounting table 18 in such a posture that its output shaft 20 protrudes toward the front side of the vehicle body.

  A transmission device (an example of a transmission) 21 is provided in front of and under the engine 19 to decelerate the power from the engine 19 and divide it into traveling and working. Inside the transmission device 21, a clutch (not shown) for interrupting working power is provided. A hydrostatic continuously variable transmission (an example of a transmission, hereinafter abbreviated as HST) 22 to which traveling power from the transmission 21 is transmitted is connected to the left and right sides of the transmission 21. Yes. A speed reducer 23 to which power after shifting by the corresponding HST 22 is transmitted is connected to the laterally outer portion of each HST 22. Each reduction gear 23 is equipped with a corresponding rear wheel 3 so as to be capable of transmission. Each HST 22 has its speed change operation shaft (not shown) linked to the corresponding speed change lever 13 so that the speed change operation is performed based on the swing operation of the corresponding speed change lever 13 in the front-rear direction.

  With this configuration, by swinging the left and right shift levers 13 in the front-rear direction, the HST 22 corresponding to each operation lever 13 can be shifted, and the left and right rear wheels 3 can be driven to shift independently. it can.

  A PTO shaft 24 that allows the working power to be taken out from the mower 5 is provided at the front lower portion of the transmission device 21. The PTO shaft 24 transmits working power to the mower 5 via an extendable transmission shaft (not shown) and a universal joint (not shown).

  A rear cover 27 formed to have left and right side walls 27A and a rear wall 27B is provided at the rear end of the rear frame 16. An upper cover 29 as an engine bonnet that covers the upper portion of the engine 19 from above is connected to the rear cover 27 so as to be able to open and close. A partition wall 32 that forms an engine room 31 together with the rear cover 27 and the upper cover 29 is erected on the side member 17 of the rear frame 16. A muffler 33 is provided behind the engine 19.

  An exhaust pipe 44 extends rearward from the muffler 33. A large-diameter exhaust pipe 45 for reducing the exhaust temperature having a diameter larger than that of the exhaust pipe 44 is disposed and connected to the rear end portion of the exhaust pipe 44. The large-diameter exhaust pipe 45 is provided to allow air to flow in between the exhaust pipe 44 and lower the exhaust gas, and to mute the exhaust sound.

  As shown in FIG. 4, an engine cooling fan 34 that rotates integrally with the output shaft 20 of the engine 19 and an air guide housing 35 that covers the engine cooling fan 34 from the front are provided at the front of the engine 19. Yes. The rotation of the engine cooling fan 34 causes the outside air to be sucked into the inside of the wind guide housing 35 through a circular air inlet 36 formed on the front surface of the wind guide housing 35, and the sucked outside air is used as cooling air. Flow toward the engine 19. The air guide housing 35 guides the cooling air from the engine cooling fan 34 to the periphery of the engine 19 to cool the engine 19 and the muffler 33. Cooling air that has cooled the engine 19, the muffler 33, and the like is discharged out of the machine from the plurality of ventilation holes 28 formed in the rear wall 27 </ b> B of the rear cover 27 and the openings 30 formed in the mounting table 18.

  As shown in FIGS. 4 and 5, the opening 30 is formed in two places on the left and right of the mounting table 18. A slide-type shutter 39 that opens and closes the opening 30 is provided on the lower surface side of the mounting table 18 so as to be slidable back and forth. The shutter 39 is interlocked with a PTO clutch lever 40 that connects and disconnects power to the PTO shaft 24 that transmits power to the mower 5, and puts the PTO clutch (not shown) into the engaged state (working state). When the lever 40 is operated, the shutter 39 is opened, and when the PTO clutch lever 40 is operated when the PTO clutch is disengaged (non-working state), the shutter 39 is closed.

  When the PTO clutch is engaged, the vehicle is generally traveling, and when the PTO clutch is disengaged, the vehicle is generally stopped or moving. In the state where the engine 19 is driven and stopped for a long time, the shutter 39 is closed, so the hot air in the engine room 31 is discharged downward from the opening 30 and blows hot air directly on the grass. Since there is nothing, it can prevent the turfgrass from withering. On the other hand, in a working state in which the PTO clutch is put, it is a state where the vehicle is working while traveling normally. In this case, since the grass pool tends to be generated, in this case, the shutter 39 can be positively opened to discharge the hot air from the opening 30, and even if the opening 30 is open during traveling, it is temporarily applied to the turf grass. The turf is never withered because only hot air is blown onto it.

  As shown in FIG. 4, clean outside air introduced from the dust removing cover 37 in front of the partition wall 32 is sucked from an outside air inlet 38 formed in the partition wall 32 and supplied to the air cleaner 72 of the engine 19.

  As shown in FIGS. 3 and 4, transmission from the engine 19 to the transmission device 21 is performed via a transmission shaft 41 and a pair of front and rear universal joints 42 that are spline-fitted to the output shaft 20 so as to be relatively slidable. Is called.

  A cartridge-type oil filter 43 that filters oil supplied to the left and right HSTs 22 is provided at the front upper portion of the transmission device 21.

  Left and right independent fuel tanks 50 and 50 for placing gasoline in the upper portions of the left and right rear wheels 3 and 3 are disposed behind the left and right fenders 12 and 12 of the traveling body 1. As shown in FIG. 6, the left and right fuel tanks 50, 50 are long in the front-rear direction and are formed in a shape provided with a recess that avoids the lops frame 14.

  The gasoline in the fuel tank 50 is partially vaporized in the tank. Vaporized vaporized gas (fuel gas) is sucked and burned in the intake stroke of the engine 19. FIG. 7 is a block diagram showing the fuel system. Connection members 68 of the gas path 51 serving as connection ports are attached to the front and rear end portions of the left and right fuel tanks 50 at the front and rear portions separated from each other. The gas passages 51, 52, 53 between the left and right fuel tanks 50 and the engine 19 are provided with a transpiration gas separation tank 55, a 2-way valve 56, and a canister 57. The vaporized gas (vaporized fuel gas) generated in the fuel tank 50 passes through the vaporized gas separation tank 55 and is adsorbed by the canister 57, and the fuel gas separated from the canister 57 during the intake stroke of the engine 19 together with the air (Hereinafter, this is simply referred to as the engine 19 as appropriate). When the fuel tank 50 is full, the traveling machine body 1 tilts or the internal pressure in the fuel tank 50 rises, and the liquid fuel in the fuel tank 50 (hereinafter referred to as gasoline) passes through one of the front and rear gas paths 51. Flows into the transpiration gas separation tank 55 and the liquid level rises above the transpiration gas separation tank 55, the shut-off valve 71 is closed, and the gasoline that has flowed in the other gas path 51 or both the front and rear. It returns to the fuel tank 50 through the gas path 51.

  The transpiration gas separation tank 55 is for collecting the fuel gas transpiration in the fuel tank 50 and sending it to the canister 57. The transpiration gas separation tank 55 is interposed between the gas paths 51 and 52 between the fuel tank 50 and the canister 57. Has been. 7 is disposed between the lower end and the upper end of the fuel tank 50 on the inner side of the fuel tank 50 in the left-right direction.

  The gas path 51 connected to the lower end of the transpiration gas separation tank 55 is connected to two connection members 68 attached to the front and back of the upper surface of the fuel tank 50, and two purge members are connected to the fuel tank 50. By providing the connection member 68, it is difficult for air accumulation to occur, and a system that is not easily restricted by the tank shape or tank posture can be constructed.

  A shutoff valve 71 is integrally provided at the upper part of the transpiration gas separation tank 55. The shut-off valve 71 is pushed up when the gasoline flows into the transpiration gas separation tank 55 and is filled with the transpiration gas separation tank 55, closes the discharge port, and the gasoline flows into the canister 57 side. Is prevented.

  During engine operation, the gasoline in the fuel tank 50 is supplied to the engine 19 via the fuel supply paths 58 and 59 on the side where the electric pump 62 is driven. When outside air is supplied to the engine 19 via the air cleaner 72, the canister 57 is trapped inside the canister 57 by the action of negative pressure generated by the air supply from the air cleaner 72 to the engine 19 through the gas path 54. The remaining fuel gas is removed and sucked into the gas path 54 to the engine 19 through the gas path 53, and at the same time, outside air is introduced into the canister 57. Also, as the gasoline is consumed, the internal pressure of the fuel tank 50 decreases, so that air flows into the fuel tank 50 from the canister 57 side via the 2-way valve 56. The 2-way valve 56 stops the flow from the high pressure side to the low pressure side until a predetermined differential pressure is reached, and opens when the differential pressure exceeds a predetermined value.

  In the state where the engine 19 is stopped, the operation of the fuel injection device (not shown) is stopped. Therefore, the inflow of air from the air cleaner 72 through the gas path 54 leading to the engine 19 is also stopped, and the intake of outside air is not performed. I will not be broken. When gasoline is supplied to the fuel tank 50, if the liquid level in the fuel tank 50 exceeds the predetermined liquid level and a closed space is formed, the tank internal pressure increases as the liquid level rises. The two-way valve 56 is opened by the tank internal pressure, and the transpiration gas (fuel gas) is discharged to the canister 57 side and adsorbed by the canister 57 (adsorbent such as activated carbon), and the transpiration gas is suppressed from being released to the atmosphere. The

  As shown in FIG. 7, right fuel supply paths 58 and 59 for supplying gasoline from the right fuel tank 50 to the engine 19, a right filter 61, and a right electric pump 62 are provided. 19, left fuel supply paths 58 and 59 for supplying gasoline, a left filter 61, and a left electric pump 62 are provided. The gasoline is supplied from the right or left fuel tank 50 to the engine 19 through the fuel supply paths 58 and 59, the filter 61 and the electric pump 62. The surplus gasoline sent from the electric pump 62 to the engine 19 is returned to the fuel tank 50 through the fuel return path 60. The left and right electric pumps 62 are switched by switching the left and right switches 63L and 63R by switching operation of an operation switch 63 provided on the right side of the driver's seat 11 and can be operated manually, and the left electric pump 62 is stopped. Thus, the right and left electric pumps 62 can be selectively operated in a state where the right electric pump 62 is operated and a state where the right electric pump 62 is stopped and the left electric pump 62 is operated. The operation switch 63 is located in a position near the driver seat 11 at a position near the driver seat 11 in the front part of the operator panel provided on the upper surface side of the fender 12 and in a state where it is difficult to hinder the operation of other operator levers and the like. Has been deployed.

  That is, when the operation switch 63 is pushed to the right, the operation switch 63 is tilted to the right, the right switch 63R is turned on, and the right electric pump 62 is driven. When the operation switch 63 is returned to the neutral position, the left and right switches 63L and 63R are both turned off and the left and right electric pumps 62 are both stopped. When the operation switch 63 is pushed to the left from the neutral position and tilted to the left, the left switch 63L is turned on and the left electric pump 62 is driven to return the operation switch 63 to the neutral position. The left electric pump 62 stops (at this time, the right electric pump 62 is also stopped). When the operation switch 63 is further operated to the right and the switch 63R is turned on, the right electric pump 62 is driven, the drive of the electric pump 62 is switched from the left electric pump 62 to the right electric pump 62, and the supply of gasoline is left. The fuel tank 50 is switched to the right fuel tank 50.

  The remaining amount of gasoline in the fuel tank 50 is displayed on a fuel meter (not shown) on the left and right sides of the driver seat 11. When the driver looks at the fuel gauge display and determines that the remaining amount of gasoline in the left or right (for example, right) fuel tank 50 being used has decreased, the driver operates the operation switch 63 while sitting on the driver seat 11. By simply switching the switches 63L and 63R, the drive of the electric pump 62 can be switched from the right electric pump 62 to the left electric pump 62, and gasoline can be continuously supplied to the engine 19.

  The filter 61 is disposed below the fuel tank 50, the electric pump 62 is disposed below the filter 61, and the fuel tank 50 and the filter 61, and the filter 61 and the electric pump 62 are respectively connected to the fuel supply path 58. Connected through. As shown in FIG. 3, the filter 61 and the electric pump 62 are fixed to the left and right inner sides of a portion 17 a that is bent obliquely downward at an intermediate portion of the side member 17 in the left and right rear frames 16. The inlet port of the filter 61 is on the upper side, the outlet port is on the lower side, and the filter 61 is disposed obliquely forward and upward with respect to the vertical line. The electric pump 62 is also connected to the filter 61 and is inclined obliquely forward and upward.

  Since the electric pump 62 is disposed at a position away from the engine 19 in the forward direction, the electric pump 62 is not easily affected by the hot air of the engine 19 and does not increase the temperature in the electric pump 62. By disposing the filter 61 obliquely below the fuel tank 50, the passage resistance of gasoline decreases, and it becomes easy to feed gasoline with a difference in elevation. Thereby, the supply property of gasoline by its own weight is good and vapor lock does not occur at high temperatures, so that it is possible to avoid the situation where the engine 19 is difficult to stop or start. With this configuration, a pump that cannot suck in gasoline under a negative pressure, for example, an impeller-type inexpensive and simple pump with a weak suction force can be used.

[Another embodiment]
(1) FIG. 8 shows another embodiment of the fuel tank 50. The left and right fuel tanks 50 are formed in a slightly hollow shape so as to avoid the lops frame 14 in plan view. A connection member 68 of the gas path 51 serving as a connection port is attached to the front end portion and the rear portion of the upper surfaces of the left and right fuel tanks 50. When viewed from the side, the fuel tank 50 has a shape in which the lower part of the center part in the front-rear direction of the fuel tank 50 has a height of more than half of the height of the fuel tank 50 in the height direction (a large recessed part is formed in the upper part). Shape). Therefore, when the gasoline is about half the height in the height direction of the fuel tank 50, the liquid level in the fuel tank 50 is divided into front and rear. A hose connection member 69 for connecting a hose (not shown) for communicating the front side portion and the rear side portion of the fuel tank 50 is attached to the front and rear lower ends of the portions facing each other.

(2) FIG. 9 shows another embodiment of the fuel tank 50. Gasoline can easily enter the gas path 51 when the fuel filler port 75 is close to the front and rear ends of the fuel tank 50 or when the length of the fuel tank 76 of the fuel tank 50 is short. In addition, when the length of the oil supply cylinder 76 is short in the vicinity of the front and rear end sides of the fuel tank 50 at the fuel supply port 75, if the oil supply port 75 is inclined downward on the inclined surface, the amount of fuel supplied decreases, and the fuel tank The amount of oil supply is likely to change greatly due to the inclination angle of 50, and it tends to overflow when it is full. On the other hand, as shown in FIG. 9, if the fuel filler port 75 of the fuel tank 50 is provided near the center of the front, rear, left and right, and the length of the fuel cylinder 76 is increased,
1. The flow of gasoline to the gas path 51 can be prevented.
2. Even when refueling on sloping ground, the amount of refueling is unlikely to change.
3. Since the oil supply cylinder 76 is long, it does not easily overflow even when the oil supply cylinder 76 becomes full.
There is a merit.

(3) FIG. 10 is a rear view showing a fuel tank 50, a transpiration gas separation tank 55, a shut-off valve, a two-way valve, and a reflux pump 66 showing another embodiment. The left half of FIG. 10 shows a vaporized gas separation tank 55 connected to the fuel tank 50 by a hose 64 constituting a gas path, a shutoff valve 71 integrated with the vaporized gas separation tank 55, and a shutoff. A 2-way valve 56 connected to the path between the off-valve 71 and the canister 57, and a recirculation valve for recirculating gasoline that has flowed from the fuel tank 50 to the transpiration gas separation tank 55 through the hose 65 to the fuel tank 50. 1 shows a configuration in which the pump 66 is disposed on the inner side in the left-right direction of the left fuel tank 50 between the bottom of the left fuel tank 50 and the upper end of the tank. A symmetrical structure is also provided in the right fuel tank 50 (not shown).

The right half of FIG. 10 shows a vaporized gas separation tank 55 connected to the fuel tank 50 by a hose 64, and a valve unit in which a shutoff valve and a two-way valve are integrated on the upper part of the vaporized gas separation tank 55. 74 shows a configuration in which a recirculation pump 66 for recirculating gasoline flowing from the fuel tank 50 to the transpiration gas separation tank 55 through the hose 65 to the fuel tank 50 is arranged directly under the right fuel tank 50. It is. A symmetrical structure is also provided in the left fuel tank 50 (not shown).
As the recirculation pump, a diaphragm pump or an electromagnetic pump using the negative pressure of the engine 19 can be used, and the gasoline stored in the transpiration gas separation tank 55 is forcibly returned to the fuel tank 50. By using the shut-off valve 71 and the pump 66, the transpiration gas separation tank 55 can be provided at a position lower than the fuel tank 50, and there is no restriction on the arrangement, so that the system can be miniaturized.

(4) In the above-described embodiment, the operation switch 63 is configured as a switch that can be tilted left and right. However, the operation switch 63 can be tilted back and forth, a toggle switch, a dial switch, and a push button. You may comprise with different types of switches, such as a switch of a formula. Further, a configuration may be adopted in which a switch for operating only the right electric pump 62, a switch for operating only the left electric pump 62, and a switch for stopping the right and left electric pumps 63 are separately provided. . In this case, the arrangement of the plurality of switches can be appropriately set. For example, the plurality of switches may be arranged side by side adjacent to each other, or the plurality of switches may be arranged side by side adjacent to each other. Good.

(5) In the above-described embodiment, an example is shown in which the operation switch 63 is configured to be operable at a neutral position where the right and left electric pumps 63 are stopped. An operation switch that displays two states of a state in which only the pump 62 is operated and a state in which only the left electric pump 62 is operated may be used.

(6) In the above embodiment, the example in which the operation switch 63 is provided on the right side portion of the driver seat 11 has been described. However, the operation switch 63 may be provided on the left side portion of the driver seat 11, for example, a tractor In other working vehicles, the operation switch 63 may be provided on a driving panel or the like provided below the steering handle in front of the driver seat 11.

(7) In the above embodiment, the operation switch 63 is provided on the front part of the operation panel provided on the upper surface side of the fender 12. However, the operation switch 63 may be operated in a state where it is seated on the driver seat 11. For example, it may be arranged at a different position of the fender 12, for example, at the rear or front surface of the fender 12, or at a different location other than the fender 12, for example, the upper surface side of the seat support frame located between the driver's seat 11 and the fender 12 You may arrange | position in the front surface etc. of the seat support frame which supports the driver's seat 11. FIG.

  The present invention provides a front mower in which a mower 5 is arranged in front of a front wheel 2 in addition to a mid-mount mower in which a mower 5 is provided between left and right front wheels 2 and left and right rear wheels 3 in a four-wheel drive type traveling vehicle body 1. It can also be applied to other work vehicles such as a tractor as well as a riding mower.

DESCRIPTION OF SYMBOLS 1 Traveling machine body 19 Engine 50 Fuel tank 58,59 Fuel supply path 61 Filter 62 Electric pump 63 Operation switch

Claims (4)

  Left and right fuel tanks with independent fuel tanks on the left and right, a right fuel supply path for supplying fuel from the right fuel tank to the engine and a right electric pump, and fuel supplied from the left fuel tank to the engine A state in which the left electric pump is stopped and the right electric pump is operated, and a state in which the right electric pump is stopped and the left electric pump is operated. And a work vehicle provided with an artificially operable operation switch for operating the right and left electric pumps.   The work vehicle according to claim 1, wherein the left and right electric pumps are respectively disposed below the left and right fuel tanks.   A filter is disposed below the fuel tank, the electric pump is disposed below the filter, and the fuel tank and the filter, and the filter and the electric pump are connected to each other via the fuel supply path. The work vehicle according to claim 2.   The work vehicle according to claim 3, wherein an inlet port of the filter is on an upper side, an outlet port is on a lower side, and the filter is disposed obliquely with respect to a vertical line.

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