JP5379821B2 - Work vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To construct a working vehicle to miniaturize a hydraulic system by a reasonable disposition of an electric hydraulic pump. <P>SOLUTION: In the working vehicle that includes an engine and an electric motor as a drive source for traveling, a first hydraulic pump P1p and a second hydraulic pump P2p are disposed as the electric pump in a back and forth positional relationship at a one side of a transmission case 7, and a hydraulic filter 38 is provided at the other outer side part of the transmission case 7. The lubricating oil is sucked from the transmission case 7, supplied to the hydraulic filter 38 through a suction oil path 7D. The lubricating oil filtered through the hydraulic filter 38 is sent to the first hydraulic pump P1p and the second hydraulic pump P2p from a main oil feed road 7B formed an outer side part of a bottom wall 7A through a branch oil passage 7C, supplied as an operating oil to a steering unit, a PTO clutch, an oil pressure change speed unit, and an AD clutch from the first hydraulic pump P1p and to an up and down cylinder and a rolling cylinder of the working machine from the second hydraulic pump P2p. <P>COPYRIGHT: (C)2013,JPO&amp;INPIT

Description

  The present invention relates to a work vehicle that transmits a driving force of an electric motor operated by electric power of a power supply unit to a traveling transmission system, and more particularly to a technique for driving a hydraulic pump.

  As a work vehicle configured as described above, in Patent Document 1, a traveling electric motor is provided at the front position of the traveling machine body, and an electric motor (hydraulic system motor in the literature) is provided at the lateral side position. A hydraulic cylinder for steering a power steering device and a hydraulic cylinder for raising and lowering a working device are shown as hydraulic equipment that includes a hydraulic pump driven by the electric motor and is supplied with hydraulic oil from the hydraulic pump. .

  Moreover, in this patent document 1, as a comparative example, an engine is provided at the front position of the traveling machine body, an electric motor is attached to the side of the engine, and a hydraulic pump driven by the electric motor is provided. Has been.

  In any of the configurations disclosed in Patent Document 1, the hydraulic circuit is configured so that the hydraulic oil in the hydraulic cylinder is returned to the transmission case by using the rear transmission case provided at the rear of the traveling machine body as a hydraulic tank.

Japanese Patent Laid-Open No. 2003-9607

  As described in Patent Document 1, in a work vehicle equipped with a hydraulic pump driven by an electric motor, when the hydraulic equipment is operated, the electric motor is driven and hydraulic oil from the hydraulic pump is used for work such as a hydraulic cylinder. Since it can be supplied to a device, it has a good surface that can suppress useless driving.

  However, as described in Patent Document 1, in the case where an electric motor and a hydraulic motor are arranged at the front position of the traveling machine body and the transmission case is arranged at the rear position of the traveling machine body, the lubricating oil of the transmission case is operated. Since the piping for supplying oil to the hydraulic pump is formed with a long dimension in the front-rear direction of the traveling machine body, the length of the members constituting the hydraulic circuit is increased and there is room for improvement.

  An object of the present invention is to rationally configure a work vehicle that reduces the size of a hydraulic system by rationally arranging an electric hydraulic pump.

A feature of the present invention is a work vehicle that transmits a driving force of an electric motor that is operated by electric power of a power supply unit to a traveling transmission system, and includes a traveling machine body that includes a pair of left and right front wheels and a pair of left and right rear wheels. The traveling machine body is provided with an engine, a transmission housing, and a transmission case in that order from the front side in a state extending from the front wheel to the rear wheel in the front-rear direction of the traveling machine body, and the engine includes the traveling transmission system and the The transmission case is configured to transmit a driving force to the electric motor, and the transmission case is configured to transmit the driving force of the electric motor to the traveling transmission system, and the front wheel is disposed in the longitudinal direction of the traveling body in the transmission case. one of the outer portions of the left and right direction which is located between the axle and the axle of the rear wheel, an electric hydraulic pump that operates by the power of the power supply unit distribution Is, the electric hydraulic pump is configured for supplying the hydraulic devices of the running vehicle body as a working oil sucked lubricating oil of the transmission case, the electric hydraulic pump, the one outer portion of the transmission case The first hydraulic pump that supplies hydraulic oil to the steering unit that is disposed at the front position and performs the steering operation of the front wheels as the hydraulic device, and the lifting and lowering operation of the work device at the rear of the traveling machine body that is disposed at the rear as the hydraulic device And a second hydraulic pump for supplying hydraulic oil to the lifting actuator .

According to this configuration, the electric motor operates by supplying power from the power supply unit, and the driving force of the electric motor is transmitted from the transmission case to the traveling transmission system, thereby enabling traveling. In addition, since the electric hydraulic pump arranged on one side of the transmission case supplies the lubricating oil of the transmission case as hydraulic oil to the hydraulic device of the traveling machine body, a pipe that supplies the hydraulic oil from the transmission case to the electric hydraulic pump The path can be very short.
Thus, the work vehicle to reduce the size of the hydraulic system could be configured by setting the relative positional relationship between the drive force transmission case and an electric hydraulic pump that is transmitted is an electric motor.
Further, according to this configuration, the hydraulic oil of the first hydraulic pump at the front position is supplied to the steering unit of the front wheel, and the hydraulic oil of the second hydraulic pump at the rear position is supplied to the rear lifting actuator. The size of the oil passage formed between the first hydraulic pump and the steering unit can be shortened, and the size of the oil passage formed between the second hydraulic pump and the lifting actuator can be shortened. The miniaturization is realized. In particular, by providing the first hydraulic pump and the second hydraulic pump independently as described above, only one of them can be driven when hydraulic oil is required, and wasteful driving can be further suppressed.
The present invention includes a first pump motor in which the first hydraulic pump is operated by electric power and a first pump driven by the first pump motor, and the second pump motor in which the second hydraulic pump is operated by electric power, The first pump is disposed at a rear position of the first pump motor, the second pump is disposed at a front position of the second pump motor, and the first pump A distribution valve that distributes and feeds hydraulic oil from the first pump or the second pump may be arranged at an intermediate position of the second pump.
According to this, since the first pump, the second pump, and the distribution valve are arranged in the space between the first pump motor and the second pump motor, for example, the vehicle travels in an environment where there is a plant or a ground protrusion. Even when the aircraft is moved forward, the first pump motor will be removed by contact with the vegetation or protrusions, and these may be damaged by contact with any of the first pump, the second pump, and the distribution valve. Eliminate. Further, when the traveling machine body is moved backward, the second pump motor comes into contact with any one of the first pump, the second pump, and the distribution valve by removing the second pump motor in contact with the vegetation or the projecting object. To solve the problem of damage.

  In the present invention, a hydraulic filter for filtering the lubricating oil supplied to the electric hydraulic pump is arranged on the other outer side opposite to the one outer side where the electric hydraulic pump is arranged in the mission case. May be.

  According to this, the lubricating oil of the transmission case can be supplied to the electric hydraulic pump, and even when a large hydraulic filter is used, the hydraulic filter does not interfere with the electric hydraulic pump, and both sides of the transmission case are The hydraulic system can be configured by effectively utilizing the space of the section.

  In the present invention, an internal oil passage for sending lubricating oil filtered by the hydraulic filter to the electric hydraulic pump may be formed independently of the internal space of the transmission case.

  According to this, hydraulic oil filtered by the hydraulic filter arranged on the other side of the mission case can be supplied to the electric hydraulic pump arranged on the other side of the mission case via the internal oil passage. It is not necessary to perform the work of providing piping outside the case, and the assembly of the hydraulic system is facilitated.

  In the present invention, as the electric motor, one that functions as a generator is used, and the power supply unit is provided with a secondary battery, and an engine that transmits driving force to the travel transmission system and the electric motor is provided. Charge / discharge control means for switching between a charging mode for charging the electric power generated by the electric motor to the secondary battery of the power supply unit and a driving mode for supplying electric power from the power supply unit to the electric motor. May be.

  According to this, the charge / discharge control means supplies the secondary battery with the electric power generated by the electric motor from the driving force of the engine, supplies the electric power from the secondary battery to the electric motor, and drives the electric motor. Switching to a driving mode for transmitting force to the traveling system is realized, and the work vehicle can be configured in a hybrid type.

It is the whole tractor side view. It is sectional drawing which shows the structure inside a transmission housing. It is sectional drawing which shows the procedure at the time of connecting a rotor to the output shaft of an engine. It is a side view which shows the position of an electric hydraulic pump. It is a top view which shows the position of an electric hydraulic pump and a hydraulic filter. It is sectional drawing which shows arrangement | positioning of an oil path etc. in a hydraulic filter and a mission case. It is a hydraulic circuit diagram which shows the structure of a hydraulic system in a block form. It is a vertical side view which shows the structure of the roof part of a cabin. It is a cross-sectional top view which shows the cooling structure of a power supply unit. It is a top view of the tractor rear part which shows arrangement | positioning of an electric power control unit. It is a rear view of the tractor which shows arrangement | positioning of an electric power control unit. It is a vertical side view of the rear fender showing the arrangement of the power control unit. It is a cross-sectional top view of the rear fender which shows arrangement | positioning of an electric power control unit. It is a disassembled perspective view which shows a case part, a supply duct, and a protection plate. It is a block circuit diagram of a control system for supplying and discharging electric power.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
〔overall structure〕
As shown in FIG. 1, a diesel engine is installed inside an engine bonnet 3 at the front of a traveling machine body A having a pair of left and right front wheels 1 that can be steered (steered) and a pair of left and right rear wheels 2. 4, a transmission housing 5 that houses a generator motor M (an example of an electric motor) and a main clutch mechanism C is provided on the rear surface side of the engine 4, and a transmission case 7 is connected to the rear surface of the transmission housing 5 for traveling. A driver's seat 9 is provided between the left and right rear fenders 8 provided in a form projecting outward from the traveling machine A so as to cover the upper part of the left and right rear wheels 2 at the rear of the machine A, and the driver's seat 9 is accommodated. A hybrid tractor as a work vehicle is configured with a cabin D that forms a driving space.

  A hydraulic lift cylinder 10 as a lift actuator and a pair of left and right lift arms 11 that swing up and down by the operation of the lift cylinder 10 are provided at the rear of the traveling machine body A (the rear end side of the transmission case 7). At the rear end of the mission case 7 is provided a power take-off shaft 12 that allows the drive force to be taken out. This makes it possible to connect a ground working device such as a rotary tiller or a plow via a three-point link mechanism (not shown) that can be moved up and down by the left and right lift arms 11, and a drive type such as a rotary tiller. The driving force from the power take-out shaft 12 is transmitted to the ground work device, and the tilling work is realized.

  In this tractor, a generator motor M having both a function of a three-phase AC generator that generates electric power by the driving force of the engine 4 and a function of a three-phase AC motor that rotates by electric power supplied from the outside is used. ing. Further, a power supply unit B (FIG. 8, FIG. 15) having a secondary battery 59 such as a lithium ion type or a nickel hydrogen type and a battery management system 60 (an example of battery management means / BMS) inside the roof portion R of the cabin D. And a first power control unit E1 that converts DC power from the power supply unit B into three-phase AC power and supplies it to the generator motor M is provided below the right rear fender 8 and is hydraulically A second power control unit E2 for driving the system is provided below the left rear fender 8. Also, a main control system that performs control for converting the three-phase alternating current generated by the generator motor M into direct current, boosting it to supply it to the power supply unit B, and controlling the first and second power control units E1 and E2. Is disposed below the driver's seat 9. In addition, it calls the electric power control unit E as a high-order concept of the 1st, 2nd electric power control units E1, E2.

[Main control system]
As shown in FIG. 15, the main control system includes a main control unit 101, an engine control unit 102, a hybrid control unit 103, a motor control unit 104, and a rectifying and boosting unit 105, which are ECUs Configured as The main control system functions as charging / discharging means. When the load acting on the traveling transmission system is small, charging is performed to charge the secondary battery 59 of the power supply unit B with the generated power from the generator motor M. When the mode is selected and the load acting on the traveling transmission system exceeds a threshold value, the driving mode is to supply the power from the power supply unit B to the generator motor M by converting the power from the power supply unit B into a three-phase alternating current by the first power control unit E1. In this drive mode, the driving force of the generator motor M is transmitted to the traveling transmission system to assist the engine rotation, thereby realizing traveling without driving force shortage and engine stoppage. The traveling transmission system is a transmission mechanism such as a transmission case 7 having a function of transmitting the driving force of the engine 4 to the front wheels 1 and the rear wheels 2. Details of the transmission case 7 and the control configuration will be described later.

[Transmission housing]
As shown in FIG. 2, the engine 4, the generator motor M, the flywheel 15, and the main clutch mechanism C are provided in this order, and the transmission housing 5 described above with respect to the rear end plate 16 connected to the rear portion of the engine 4. Thus, the generator motor M, the flywheel 15 and the main clutch mechanism C are accommodated in the transmission housing 5.

  The generator motor M is composed of a rotor 22 having a permanent magnet 21 on the outer periphery and a stator 23 arranged at a position surrounding the rotor 22, and the stator 23 is formed on a plurality of teeth portions (not shown) of the stator core. It has a structure in which a coil is wound. The rotor 22 of the generator motor M is connected to the shaft end of the output shaft 4A (crankshaft) of the engine 4 coaxially with the rotational axis X of the output shaft 4A. The flywheel 15 is disposed on the surface of the rotor 22 opposite to the output shaft 4A, and these are connected by a connecting mechanism J. In this configuration, the rotor 22 is configured as a transmission unit having a function of transmitting the driving force of the generator motor M to the traveling transmission system and a function of transmitting the driving force of the engine 4 to the generator motor M.

  The coupling mechanism J is erected in a posture parallel to the rotation axis X with respect to the output shaft 4A, and is formed between a rotor through hole 22A formed in the rotor 22 and a wheel through hole 15A formed in the flywheel 15. The stud shaft 24 includes a plurality of penetrating stud shafts 24, and a nut 25 that is screwed into a screw portion 24 </ b> A at the shaft end of the stud shaft 24. From such a configuration, a state is reached in which the rotor 22 and the flywheel 15 are sandwiched between the shaft end of the output shaft 4A and the nut 25, respectively.

  The transmission housing 5 has a structure in which the front housing 5A and the rear housing 5B are detachably connected, and when the generator motor M is assembled, the stator 23 is provided on the inner surface of the front housing 5A. The front housing 5A is connected to the rear end plate 16, and then the rotor 22 is connected to the rear end of the output shaft 4A.

  In this work, in order to prevent the inconvenience that the rotor 22 is attracted to the inner surface of the stator 23 by the attractive force of the permanent magnet 21 of the rotor 22, the above-described plurality of stud shafts 24 are provided. A screw hole 22 </ b> B that penetrates in a posture parallel to X (a coaxial core in the drawing) and has a female screw on the inner surface is formed.

  This screw hole 22B is formed with a female screw portion for screwing the screw shaft 18 for adjusting the feed rate, and when connecting the rotor 22 to the output shaft 4A, as shown in FIG. A plurality of stud shafts 24 are inserted into the rotor through holes 22A of the rotor 22 in a state where the tips of the shafts 18 are screwed so as to protrude into the rotor 22, and the conical tips of the screw shafts 18 are connected to the rear surface of the output shaft 4A. Thus, it is fitted into the conical recess 4B formed on the rotation axis X. In this state, the distance between the rotor 22 and the rear end of the output shaft 4A is gradually shortened by the attractive force by which the permanent magnet 21 is attracted to the stator 23 by rotating the screw shaft 18 in the direction of extracting from the rotor 22. It will be. In a state where the rotor 22 has reached a position where it contacts the rear end of the output shaft 4A by this operation, a gap is formed between the outer periphery of the rotor 22 and the inner periphery of the stator 23, and thereafter, as shown in FIG. As shown, the rotor 22 and the flywheel 15 reach a connected state by inserting a plurality of stud shafts 24 through the wheel through holes 15A of the flywheel 15 and screwing and fastening nuts 25 to the stud shafts 24. . Further, a concave fitted portion 4C that is coaxial with the rotational axis X is formed at the center position of the rear surface of the output shaft 4A, and a convex shape that is coaxial with the rotational axis X is formed on the front surface of the rotor 22. When the fitting portion 22C is formed and the rotor 22 is connected to the output shaft 4A, the fitted portion 4C and the fitting portion 22C are fitted to reach a firm positioning state.

  The main clutch mechanism C includes a clutch disk 28, a pressure plate 29, and a diaphragm spring 30 disposed in a clutch cover 27 that is connected to the rear surface of the flywheel 15, and a clutch shaft to which driving force from the clutch disk 28 is transmitted. 31 and a release unit (not shown) that performs the disengagement operation of the main clutch mechanism C in conjunction with the depression operation of the clutch pedal 52 shown in FIG.

  The clutch shaft 31 is supported so as to be rotatable about the rotation axis X with respect to the rear housing 5B, and the clutch disk 28 is capable of transmitting torque to the clutch shaft 31 by a spline structure and is also connected to the rotation axis X. The diaphragm spring 30 is supported so as to be displaceable along the clutch disc 28, and the urging force in the clutch engagement direction is applied to the clutch disk 28 via the pressure plate 29. The rear housing 5B is provided with a transmission system for transmitting the driving force from the rear end of the clutch shaft 31 to the intermediate transmission shaft 33 via the transmission gear 32. The driving force of the intermediate transmission shaft 33 is transmitted to the transmission case 7. .

  In the main clutch mechanism C, when the clutch pedal 52 is not operated (not depressed), the urging force of the diaphragm spring 30 acts on the clutch disk 28 from the pressure plate 29. 15 is kept in contact with the rear surface of the clutch 15 in the engaged state. On the contrary, when the clutch pedal 52 is depressed, the urging force acting on the pressure plate 29 from the diaphragm spring 30 is greatly reduced, so that the clutch disk 28 and the rear surface of the flywheel 15 are brought into a non-contact state. Reach cutting condition.

  A ring gear portion 15B is formed on the outer periphery of the flywheel 15 described above. As shown in FIGS. 4 and 5, a starter motor 19 having a pinion gear (not shown) that meshes with the ring gear portion 15B and transmits rotational force. Is arranged on the left side of the engine 4. Further, three power lines Q connected to the coils of the stator 23 of the generator motor M are connected to the right side portion of the transmission housing 5. The power line Q functions as a path through which power is supplied from a power control unit E, which will be described later, and also functions as a path for sending out the power generated by the generator motor M. In this tractor, the starter motor 19 may be disposed on the right side of the engine 4 and the power line Q may be disposed on the left side of the transmission housing 5.

[Operation / Effect in Embodiment of Configuration Relating to Generator Motor]
With such a configuration, when connecting the rotor 22 of the generator motor M to the output shaft 4A of the engine 4, the screw shaft 18 for adjusting the feed rate having a dimension sufficiently longer than the entire length of the screw hole 22B of the rotor 22 is used. The screw shaft 18 is screwed into the screw hole 22B so that both ends of the screw shaft 18 protrude from the screw hole 22B, and the stud shaft 24 provided on the output shaft 4A penetrates the rotor through hole 22A of the rotor 22. Set to state. In this state, a suction force acts between the rotor 22 and the stator 23. However, since one end of the screw shaft 18 contacts the inner surface of the recess 4B of the output shaft 4A, the rotor 22 is connected to the output shaft. Displacement in the direction approaching 4A (the direction along the rotation axis X) is suppressed. Further, the displacement in the direction in which the stud shaft 24 approaches the stator inner surface of the rotor 22 (the direction orthogonal to the rotation axis X) is suppressed.

  In this state, the other end of the screw shaft 18 is rotated by an artificial rotation or an electric actuator so as to reduce the amount of protrusion of the one end of the screw shaft 18 from the rotor 22. The rotor 22 can be displaced at an arbitrary speed in the direction approaching the output shaft 4A of the engine 4 in a state in which the influence of the suction force acting between the rotor 22 and the stator 23 is eliminated. The rotor 22 is guided, and the rotor 22 and the flywheel 15 can be connected to the output shaft 4A by the connecting mechanism J. Thus, after guiding the rotor 22 to an appropriate position, the screw shaft 18 is removed.

  Further, by utilizing the surface of the flywheel 15 opposite to the output shaft 4A, the main clutch mechanism C can be made compact without increasing the number of parts, and wear powder is generated in the main clutch mechanism C. Even so, the hindrance of the flywheel 15 prevents the wear powder from entering the generator motor M and maintains a high-performance operation. In addition, the starter motor 19 is arranged on one of the left and right sides of the transmission housing 5 and the three power lines Q connected to the coils of the stator 23 of the generator motor M are arranged on the other side. The space at the side of the housing 5 can be used effectively.

[Mission case]
As shown in FIG. 5, the transmission case 7 has a built-in hydraulic transmission unit F, and transmits the driving force shifted by the hydraulic transmission unit F from the transmission case 7 to the front wheels 1 and the rear wheels 2. A system is formed. The structure of the hydraulic transmission unit F is not shown in the drawing, but a hydraulic transmission clutch that intermittently powers the engine 4, a plurality of synchromesh transmission gears, and a plurality of transmission gears that shift the sleeves of the transmission gears. A hydraulic transmission cylinder and a transmission valve for controlling the transmission cylinder.

  The hydraulic transmission unit F realizes a configuration that realizes a shift only by operating the main transmission lever 55 (see FIG. 1) without depressing the clutch pedal 52 only by a hydraulic circuit. An example of the speed change operation is, for example, when the main speed change lever 55 is operated from the neutral position to the first forward speed position, after the speed change clutch is disengaged, the shift cylinder is operated to correspond to the first forward speed position. The changed transmission gear is set at the transmission position, and thereafter, the control for returning the transmission clutch to the engaged state is sequentially executed by hydraulic pressure.

  The travel driving force from the hydraulic transmission unit F is transmitted to the left and right rear wheels 2 via a rear differential mechanism (not shown) inside the transmission case, and a front wheel speed increasing device (inside the transmission case 7) ( A driving force from the front wheel 1 is transmitted to a differential mechanism (not shown) of the front wheel 1 via the front wheel drive shaft 35. This front wheel speed increasing device includes a gear transmission system that increases the driving speed of the front wheel 1 when the front wheel 1 is steered beyond a set angle, and a hydraulic AD clutch 35C shown in FIG. Yes. The AD clutch 35C maintains a driving state at a constant speed with the rear wheel 2 by the urging force of the spring when the traveling machine body A is traveling straight, and is switched to a high speed transmission state when the steering amount exceeds a set value.

(Hydraulic configuration)
As shown in FIG. 1, a hydraulic steering unit 36 that performs the steering operation of the front wheel 1 is provided in front of the mission case 7 and further forward of the engine 4. As shown in FIG. 7, the steering unit 36, the elevating cylinder 10, the PTO clutch 37, and the AD clutch 35C are examples of a hydraulic device. As shown in FIGS. 4 and 5, the right side of the mission case 7 is shown. The first hydraulic pump P1 is provided at the front position to supply hydraulic oil to the lower side of the step of the cabin D, and the second hydraulic pump P2 is arranged in a straight line at the rear position. A hydraulic filter 38 is attached to the left outer portion of the transmission case 7 to filter the lubricating oil in the transmission case 7 and supply it as hydraulic oil to the first hydraulic pump P1 and the second hydraulic pump P2. The first hydraulic pump P1 and the second hydraulic pump P2 constitute an electric hydraulic pump that is operated by the electric power from the power supply unit B. The lower surfaces of the first hydraulic pump P1 and the second hydraulic pump P2 The relative positional relationship is set so as to be located above the lower surface.

  The first hydraulic pump P1 includes a first pump motor P1m that is operated by electric power and a first pump P1p that is driven thereby, and the second hydraulic pump P2 is a second pump motor P2m that is operated by electric power, It is comprised with the 2nd pump P2p driven by this. The first pump motor P1m has a drive shaft projecting on the rear side. The first pump P1p is connected to the drive shaft, and the second pump motor P2m has a drive shaft projecting on the front side. A pump P2p is connected, and a distribution valve 39 that distributes and feeds hydraulic oil from the first pump P1p is disposed at an intermediate position between the first pump P1p and the second pump P2p. In particular, the axial center of the drive shaft of the first pump motor P1m and the axial center of the drive shaft of the second pump motor P2m are set in a positional relationship in which they are close to each other in the vertical and horizontal directions of the machine body. In this hydraulic configuration, instead of the configuration in which the hydraulic oil from the first hydraulic pump P1 is distributed by the distribution valve 39, the hydraulic oil from the second hydraulic pump P2 may be distributed by the distribution valve 39.

  The first pump motor P1m and the second pump motor P2m are configured as three-phase motors, and three-phase AC power is supplied from the second power control unit E2. In addition, the amount of hydraulic oil sent out by the second hydraulic pump P2 is set to be larger than that of the first hydraulic pump P1, and the second pump motor P2m has a larger capacity and a larger electric motor than the first pump motor P1m. Is used. As the first pump motor P1m and the second pump motor P2m, those capable of controlling the rotation speed such as a brushless DC motor may be used.

  As shown in FIG. 6, the main oil supply to the left and right sides of the machine body separated from the internal space of the mission case 7 is sent to the bottom wall portion 7 </ b> A of the mission case 7 so that the lubricating oil filtered by the hydraulic filter 38 is sent out as working oil. A path 7B (an example of an internal oil path) is formed from one end to the other end of the bottom wall portion 7A, and a branched oil supply path 7C (an example of an internal oil path) branched from the main oil supply path 7B in the longitudinal direction of the machine body. Further, a suction oil passage 7D for supplying lubricating oil stored in the internal space to the hydraulic filter 38 is formed in the wall portion of the mission case 7. The mission case 7 is a casting, and the main oil supply passage 7B, the branch oil supply passage 7C, and the suction oil passage 7D are formed integrally with the mission case 7 at the time of casting.

  The hydraulic oil from the main oil supply path 7B is supplied to the second pump P2p via the second oil supply pipe L2, and the hydraulic oil from the branch oil supply path 7C is supplied to the first pump P1p via the first oil supply pipe L1. Is done.

  As shown in FIG. 7, the hydraulic oil from the first pump P1p is supplied to the steering unit 36 that performs the steering operation of the front wheel 1 via the distribution valve 39 and also to the PTO clutch 37 ( Strictly speaking, it is supplied to the control valve of the PTO clutch 37), the hydraulic transmission unit F, and the AD clutch 35C (strictly, the control valve of the AD clutch 35C). Further, the hydraulic oil from the second pump P2p is supplied to the lifting cylinder 10 (strictly, the control valve of the lifting cylinder 10) at the rear of the traveling machine body A, and the rolling cylinder 13 that controls the rolling posture of the ground working device. (Strictly speaking, a rolling control valve).

[Operation / Effect in Embodiment Related to Hydraulic Configuration]
From such a hydraulic configuration, when the hydraulic device is operated, the hydraulic device is not operated by operating the first pump motor P1m of the first hydraulic pump P1 or the second pump motor P2m of the second hydraulic pump P2. In this case, it is possible to eliminate wasteful power consumption. Also, two hydraulic pumps, a first hydraulic pump P1 and a second hydraulic pump P2, are arranged as an electric hydraulic pump on one outer side of the mission case 7, and a hydraulic filter 38 is arranged on the other outer side of the mission case 7. Therefore, not only the hydraulic path length between the transmission case 7 and the hydraulic pump is minimized, but the hydraulic system is reduced in size. For example, a hydraulic pump and a hydraulic filter 38 are provided on one outer side of the transmission case 7. Compared with the arrangement of the hydraulic system, it is possible to configure the hydraulic system by effectively using the space on both sides of the mission case 7.

  In addition, since the first pump P1p, the second pump P2p, and the distribution valve 39 are arranged in the space between the first pump motor P1m and the second pump motor P2m, for example, there are vegetation and ground protrusions. Even when the traveling machine body A is moved forward in the environment, the first pump motor P1m comes into contact with the vegetation and the projecting object to eliminate it, so these contact any one of the first pump P1p, the second pump P2p, and the distribution valve 39. To eliminate the inconvenience of damage. Further, when the traveling machine body A is moved backward, the second pump motor P2m is in contact with the vegetation and the projecting object and is eliminated, and the first pump P1p, the second pump P2p, and the distribution valve 39 are removed. Eliminate the inconvenience of being damaged by touching any of them.

  In this hydraulic configuration, two hydraulic pumps of the first hydraulic pump P1 and the second hydraulic pump P2 are shown as the electric hydraulic pumps. However, one electric hydraulic pump may be provided, and three or more hydraulic pumps may be provided. May be. Further, the distribution valve 39 may be configured to distribute the hydraulic oil to other hydraulic devices. The electric hydraulic pump is disposed on the left side of the mission case 7 and the hydraulic filter 38 is disposed on the right side of the mission case 7. Also good. Further, the arrangement of the first hydraulic pump P1 and the second hydraulic pump P2 may be reversed from the configuration described above, and the first hydraulic pump P1 may be arranged at the rear and the second hydraulic pump P2 may be arranged.

〔cabin〕
The cabin D includes a pair of left and right front pillars 41 having a pillar shape at the front, a pair of left and right intermediate pillars 42 having a pillar shape in the middle in the front-rear direction, a pair of left and right rear pillars 43 having a pillar shape at the rear, A top frame 44 connected to these upper portions and a roof portion R disposed at a position covering the top frame 44 are provided. A windshield 45 is provided at a position sandwiched between the left and right front pillars 41 at the front portion of the cabin D, and a glass door 46 is provided between the front pillar 41 and the intermediate pillar 42 at both sides so as to be freely opened and closed. A side glass 47 is provided between the intermediate pillar 42 and the rear pillar 43 at a rear position 46, and a rear glass 48 is provided at a position sandwiched between the left and right rear pillars 43 at a rear position. In this configuration, a steel material in which a pair of left and right front pillars 41, a pair of left and right intermediate pillars 42, and a pair of left and right rear pillars 43 are U-shaped in cross section is used, and the top frame 44 is welded to the upper ends thereof. It is fixed.

  The cabin D has an airtight structure that prevents external dust and noise from entering the driving space, and an air conditioner S is provided at the rear of the roof portion R as an air conditioner for cooling and heating the cabin. Equipped

  As shown in FIGS. 1 and 10, inside the cabin D, a steering wheel 51 for steering the front wheel 1 is disposed at the front position of the driver seat 9, and below the left side of the steering wheel 51. A clutch pedal 52 is disposed, and a pair of left and right brake pedals 53 and an accelerator pedal 54 are disposed on the lower right side. Further, on the right side of the driver's seat 9, a main transmission lever 55 that changes the speed of the transmission case 7 and an elevating lever 56 that controls the elevating cylinder 10 are arranged.

[Cabin: Cooling configuration of power supply unit]
The power supply unit B provided in the roof portion R of the cabin D sucks air outside the cabin and supplies it to the secondary battery 59 and the battery management system 60 as cooling air for the purpose of suppressing the temperature rise of the secondary battery 59. A cooling system is provided.

  As shown in FIGS. 8 and 9, the roof portion R includes a bottom wall 61 that is supported by the top frame 44 and is disposed on the interior space side of the cabin and functions as a ceiling wall in the cabin, and an upper wall on the upper side. 62 and a further upper outer wall 63, a roof inner space K is formed between the bottom wall 61 and the upper wall 62, and a ventilation space T is formed between the upper wall 62 and the outer wall 63. Yes. In this roof portion R, the bottom wall 61 and the upper wall 62 may be made of either a metal material or a resin material, but the outer wall 63 and the upper wall 62 are made by blow molding a resin material. This makes it difficult to raise the temperature of the ventilation space T and the space K in the roof even in an environment where direct sunlight shines. In addition, the ventilation space T should just be formed separately from the cooling space N in the roof part R, for example, the structure formed in the side part and rear part of the roof part R may be sufficient.

  The secondary battery 59 of the power supply unit B has a configuration in which a plurality of cells functioning as batteries are electrically connected. The secondary battery 59 is disposed at the front and rear of the roof portion R and at the center of the left and right. A battery management system 60 is disposed in the vicinity. In the roof inner space K, a unit housing case 64 for housing the power supply unit B, an intake duct 65 for supplying air outside the cabin to the unit housing case 64, and an exhaust for sending air from the unit housing case 64 to the outside of the cabin. A cooling space N having a duct 66 is formed, and the front fan is configured to suck air outside the cabin through the intake duct 65 and discharge the air from the unit housing case 64 to the outside of the cabin through the exhaust duct 66. 67 is provided inside the intake duct 65, and a rear fan 68 is provided inside the exhaust duct 66. In addition, one of a plurality of resistors is selected for the current supplied from the power supply unit B to the power control unit E independently of the above-described cooling space N on the front side of the roof space K. Thus, the relay box G for applying electric resistance is arranged in an inclined posture in which the forward side is inclined inward of the airframe.

  The power supply unit B includes a secondary battery 59 and a battery management system 60, and is assumed to be housed in a form that is exposed inside the unit housing case 64. The battery management system 60 may be housed in a box and the box may be housed in the unit housing case 64. The unit housing case 64 has an introduction space 64B having a smaller sectional area on the upstream side in the air flow direction on the front end side of the battery housing space 64A, and a smaller sectional area on the downstream side in the air flow direction on the rear end side. A discharge space 64C is formed.

  The intake duct 65 is formed with an air intake portion 65 </ b> A that expands in the lateral direction at the front end portion, a front fan 67 is disposed at an intermediate portion of the air intake duct 65, and a discharge portion of the front fan 67 serves as a unit housing case 64. It is connected to the front end of the introduction space 64B. In order to introduce air into the air intake portion 65A, an air intake opening Ra is formed in the left and right central portion of the front end portion of the roof portion R. A rear guide plate 69R that protrudes obliquely forward and downward from the upper portion is disposed, and an air filter 70 is provided in the intake portion 65A. In particular, in an intermediate region between the front guide plate 69F and the rear guide plate 69R, an open portion (not shown) for discharging rainwater and the like by being opened downward is formed.

  The front fan 67 is a sirocco fan that is driven to rotate about the left and right axis, and the rear fan 68 is an axial fan that is driven to rotate about the front and rear axis. As a fan for sucking outside air into the cooling space N, only one of the front fan 67 and the rear fan 68 may be provided.

  The exhaust duct 66 has a front end connected to the rear end of the battery storage space 64A of the unit storage case 64, and a rear end of the exhaust duct 66 connected to an exhaust opening Rb formed at the left and right center of the rear end of the roof portion. The exhaust opening Rb includes a front discharge guide plate 71F that protrudes obliquely forward and upward from the lower portion, and a rear discharge guide plate 71R that protrudes obliquely rearward and downward from the upper portion.

[Operation / Effect in Embodiment of Configuration Relating to Power Supply Unit]
With such a configuration, when the front fan 67 and the rear fan 68 are driven and the outside air is sucked into the cooling space N, as shown in FIG. The air flows around the lower end of the guide plate 69R. After the dust is removed by the air filter 70, the air flows into the intake duct 65. In addition, since the power supply unit B is disposed in the roof inner space K inside the roof portion R, rainwater does not directly contact the power supply unit B, and when the outside air is sucked, the intake opening Even when rainwater and dust can enter Ra, the rainwater and dust are not sucked into the intake duct 65 by discharging the rainwater and dust downward from an open portion (not shown). Intruding into the secondary battery 59.

  The air sucked into the intake duct 65 removes heat by contacting the secondary battery 59 housed in the battery housing space 64 </ b> A of the unit housing case 64 and the outer surface of the battery management system 60. Suppress the upper temperature. The air thus deprived of heat is sent from the exhaust duct 66 to the exhaust opening Rb, and the air that has passed through the upper side of the front discharge guide plate 71F flows in a form that wraps around the lower side of the rear discharge guide plate 71R, and the roof portion. It is discharged outside R. Further, since the exhaust opening Rb is provided with the rear discharge guide plate 71R, even when rainwater or dust enters from the exhaust opening Rb, the intrusion is suppressed and discharged from the rear end of the exhaust opening Rb. It is.

[Cabin: Air conditioning configuration]
As shown in FIGS. 8 and 9, the air conditioner S is provided at a position where the air conditioner S projects further rearward than the rear pillar 43 at the rear end position of the roof portion R. The air conditioner S is supported by a horizontal frame provided across the pair of left and right rear pillars 43 at a height lower than the upper ends of the pair of left and right rear pillars 43. The air conditioner S includes an air conditioning unit 75 having an evaporator (not shown) and an electric heater inside, and a blower fan 77 that sends air to the air conditioning unit 75. Inside the cabin D, an air inlet 80 is formed below the bottom wall 61 (the ceiling wall in the cabin), and air sent from the air conditioner S is supplied to the inside of the cabin D on the left and right sides of the bottom wall 61. A pair of left and right air conditioning ducts 78 is provided.

  In this air conditioner S, it is assumed that cooling is realized by driving a compressor and radiating the compressed refrigerant with a condenser, then expanding it in an expansion valve and supplying it to the evaporator. You may comprise as a heat pump type switchable with heating.

  The bottom wall 61 is formed with an inclined wall portion 61A that bends obliquely downward at the front position of the air conditioner S, and an extended wall 79 that extends rearward from the upper end side of the inclined wall portion 61A. An air conditioner S is disposed between the rear of the inclined wall portion 61 </ b> A and the extending wall 79, and an intake space H for supplying air to the blower fan 77 is formed. Note that the blower fan 77 is a sirocco fan that sucks air from the upper end and sends air in the direction of the air conditioning unit 75 on the side.

  In addition, a vertical ventilation duct 81 communicating with the intake space H is connected to the ventilation space T described above, and a switching plate 82 that can be opened and closed is provided. The ventilation space T communicates with the outside through a ventilation port 72 formed on the side of the roof portion R. The ventilation duct 81 is disposed at a position adjacent to the battery housing space 64A of the unit housing case 64, and a portion of the unit housing case 64 adjacent to the outer wall of the battery housing space 64A is formed in an oblique posture in plan view as shown in FIG. It is formed in a pipe shape.

  The switching plate 82 is configured to be openable and closable by human operation. When the switching plate 82 is operated in the open posture shown by the solid line in FIG. Outside air can be sucked into the ventilation space T from the ventilation port 72, and this outside air can be supplied from the ventilation duct 81 to the intake space H.

[Operations and effects in the embodiment related to the air conditioning configuration]
Due to such a configuration, when the air conditioner S is moved with the switching plate 82 set to the closed posture, the temperature is adjusted by the air conditioning unit 75 sucked from the air intake port 80 in the cabin, and this air is air-conditioned duct. By sending the air through the cabin through 78, air conditioning in a circulation mode in which air conditioning is performed while circulating air in the cabin is realized.

  Further, when the air conditioner S is operated with the switching plate 82 set to the open posture, the outside air from the ventilation space T is removed from the ventilation duct in a state in which the intake port 80 is closed and the intake of the air in the cabin is shut off. Air conditioning in the outside air mixing mode in which the air is mixed with the outside air and air in the cabin is performed by suctioning at 81 and adjusting the temperature by the air conditioning unit 75 and then sending it out through the air conditioning duct 78 into the cabin. To do. Moreover, since it is the structure which takes in air from the ventilation space T, for example, compared with the structure which takes in the air which the heat | fever of the power supply unit B acted and the temperature rose, the waste of energy at the time of cooling with the air conditioner S is wasted. Absent.

  Particularly, since the power supply unit B is provided for the roof portion R of the cabin D and the air conditioner S is provided as an air conditioner, it is not necessary to secure a space for installing the power supply unit B in the traveling machine body A. Compared with the air conditioner S driven by the air conditioner 4 provided in the traveling machine body A, it is not necessary to adopt a configuration in which the piping for supplying and discharging the refrigerant from the compressor is drawn into the cabin D, and the configuration is simplified. . Further, since the power supply unit B and the air conditioner S are provided in the roof portion R, it is not only necessary to secure a space for the power supply unit B and the air conditioner S in the traveling machine body A. These can be provided compactly with respect to the roof portion R which can be easily changed in design.

[Power control unit]
The first power control unit E1 on the right side and the second power control unit E2 on the left side have basically the same configuration except that the power output targets are different, so these are collectively referred to as the power control unit E. explain. As shown in FIGS. 10 to 14, the power control unit E is provided on the lower side of the rear fender 8 and on the upper side of the rear wheel 2. As described above, the power control unit E is configured as a VVVF type inverter that generates a three-phase alternating current having a set frequency at a set voltage.

  This power control unit E realizes good heat dissipation by being disposed below the rear fender 8, but it is disposed at a position above the rear wheel 2 so that it jumps at the rear wheel 2 during work or the like. There is a means to regulate the contact of raised mud and pebbles. The power control unit E is accommodated in the case portion 85 as the restricting means, and a protection plate 86 in a horizontal posture is disposed as a restricting means below the case portion 85. The protection plate 86 is made of a high-strength material such as steel, and is connected and fixed to the vertical wall 8A of the rear fender 8, and is further connected to the upper surface of the protection plate 86 in such a manner that the case portion 85 is supported. . The lower surface of the protective plate 86 is provided with a scraper 87 which is made of a high-strength material such as steel on the rear end side and protrudes downward. A partition wall having a vertical wall shape on the rear end side of the upper surface of the protective plate 86. 88 is provided. In addition, although the structure which connected the case part 85 with respect to the upper surface of the protection plate 86 is shown in drawing, you may form a clearance gap between these. Further, the scraper 87 may be provided at one position of the front position of the protective plate 86, or at two positions of the front position and the rear position, or may be provided at three positions or more.

  The case portion 85 has a structure in which the front end and the rear end are open, and a supply duct 89 that guides the air in the cabin to the power control unit E as cooling air is formed on the front end side. A cooling fan 90 is provided at an intermediate portion between the case 89 and the case portion 85. The vertical wall 8A of the rear fender 8 to which the supply duct 89 is connected is formed with a suction hole 89A in the shape of a hole, and the end of the bulkhead 88 on the center side of the bulkhead 88 so as to send out air that has passed through the inside of the case 85 An open space 88 </ b> S is formed between the vertical wall 8 </ b> A of the rear fender 8.

  Also, an output cable 91 that supplies power from the first power control unit E1 to the generator motor M, and a power cable 92 (an example of a power cable) that supplies DC power from the power supply unit B to the first power control unit E1. The control cable 93 is formed so as to penetrate the side wall inside the traveling machine body in the first power control unit E1 and extend into the cabin on the center side of the traveling machine body A. Similarly, an output cable 91 that supplies power from the second power control unit E2 to the first pump motor P1m of the first hydraulic pump P1 and the second pump motor P2m of the second hydraulic pump P2, and the second power A power cable 92 (an example of a power cable) for supplying DC power from the power supply unit B to the control unit E2 and a control cable 93 are provided on the side wall on the inner side of the traveling machine body and the longitudinal fender 8 in the second power control unit E2. The wall 8 </ b> A is formed so as to extend into the cabin on the center side of the traveling machine body A.

[Operation / Effect in Embodiment of Configuration Relating to Power Control Unit]
From such a configuration, by disposing the power control unit E in the space opened downward while effectively using the space between the lower side of the rear fender 8 and the rear wheel 2, good heat dissipation can be realized. I'm making things. In particular, since the restricting means including the case portion 85 and the protective plate 86 is provided, the pebbles and mud that are flipped up from the rear wheel 2 are not attached to or damaged by the power control unit E. Even in the situation where dirt or scum attached to the rear wheel 2 is brought into the rear fender 8, the scraper 87 comes into contact with the soil or scum and is scraped off from the rear wheel 2, thereby impairing the cooling effect. Nor.

  Furthermore, clean air in the cabin is sucked through the intake holes 89A and supplied to the power control unit E by the cooling fan 90, whereby clean air can be supplied to the power control unit E to dissipate heat. The air that has cooled the power control unit E in this way is sent out from the rear end of the case portion 85 and discharged backward from the open space 88S. With this configuration, it is possible to achieve good cooling that combines cooling performed by directly contacting air outside the traveling machine body A and cooling performed by supplying air from the cabin D.

  In addition, the power control unit E is not necessarily arranged below the rear fender 8, and a part of the power control unit E protrudes upward from the upper surface of the rear fender 8, and a part thereof is in the cabin (inside the traveling machine body A). You may arrange | position with the form which protrudes. Even if it is the structure arrange | positioned in this way, the favorable surface of arrange | positioning the electric power control unit E in the site | part of the rear fender 8 is not spoiled.

(Power control configuration)
An outline of the power control configuration of the tractor is shown in FIG. This power control configuration includes a power supply system having a power cable 92 that supplies DC power from the secondary battery 59 of the power supply unit B to the first and second power control units E1 and E2 via the relay box G. ing. The first power control unit E1 converts the supplied DC power into three-phase AC power and supplies it to the generator motor M via the output cable 91, and the second power control unit E2 converts the supplied DC power into three-phase power. It is converted into AC power and supplied to the first pump motor P1m and the second pump motor P2m via the output cable 91. Although not shown in the drawing, the second power control unit E2 also supplies power to the compressor of the air conditioner S.

  As described above, the main control system includes the main control unit 101, the engine control unit 102, the hybrid control unit 103, the motor control unit 104, and the rectifying and boosting unit 105.

  The engine 4 has a common rail fuel injection system. In order to control this fuel injection, the engine control unit 102 detects a signal from the accelerator pedal sensor 54S and a rotational speed sensor 99 (see FIG. 2), a signal from a fuel pressure sensor (not shown) for detecting the pressure of the fuel in the common rail, a signal from an intake pressure sensor (not shown) at the intake portion, etc. (Not shown) is performed to determine the operation timing. From such a configuration, the engine control unit 102 can also determine the load acting on the engine 4, and the generator such as the load acting on the engine 4, the rotational speed of the engine 4, the amount of depression of the accelerator pedal 54, etc. Information necessary for driving the motor M is output to the main control unit 101. The rotational speed sensor 99 is provided in a state of being inserted through a hole penetrating the front housing 5A of the transmission housing 5 up and down, and a sensing portion at the lower end is brought close to the outer periphery of the flywheel 15 to change the flywheel from the change in magnetic flux density. The pickup type is configured to count 15 rotations. The rotation speed sensor 99 may optically count the rotation of the output shaft 4A, the flywheel 15 and the like.

  In this tractor, a load sensor for detecting a load acting on the engine 4 may be provided in the engine 4 or the traveling drive system, and the main control unit 101 may acquire information detected by the load sensor. The engine 4 is not limited to the diesel type, and may be a gasoline type.

  The hybrid control unit 103 outputs a control signal to the power supply unit B and the relay box G via the battery control cable 98 based on information from the main control unit 101. The motor control unit 104 outputs a control signal to the first and second power control units E1, E2 via the control cable 93 based on information from the main control unit 101.

  The rectification booster unit 105 has a function of a rectifier circuit that converts the three-phase alternating current generated by the generator motor M into a direct current, and a DC-DC converter that converts the current thus converted into a direct current into a high-voltage current. DC power is transmitted via a power transmission cable 94.

  As described above, the main control system is disposed below the driver's seat 9, the power supply unit B and the relay box G are disposed on the roof portion R of the cabin D, and the first power control is performed below the right rear fender 8. The unit E1 is disposed, and the second power control unit E2 is disposed below the right rear fender 8. From such a positional relationship, the power cable 92 that supplies DC power from the power supply unit B to the first and second power control units E1 and E2 is disposed in a state of being inserted into the right intermediate pillar 42. In addition, a battery control cable 98 that outputs a control signal from the hybrid control unit 103 of the main control system to the power supply unit B is disposed in a state of being inserted into the right rear pillar 43.

  Since such a power control configuration is provided, the engine control unit 102 executes control for operating the engine 4 in a low-speed region with good fuel consumption by a signal from the main control unit 101. When the main control unit 101 determines that the load acting on the engine 4 is less than the threshold based on the information acquired by the engine control unit 102, the rectification boosting unit 105 converts the generated power from the generator motor M into Then, the voltage is boosted to a high voltage, and the DC power boosted in this way is transmitted from the power transmission cable 94 to the power cable 92, whereby the power supply unit B is supplied and charged. When charging is performed in this way, the battery management system 60 manages the charging of the secondary battery 59. In particular, the power cable 92 is arranged inside the intermediate pillar 42 and the battery control cable 98 is arranged inside the rear pillar 43. For example, even if noise is applied to the power cable 92, the noise is transferred to the battery. The control signal sent to the control cable 98 is not affected.

  On the contrary, when the main control unit 101 determines that the load acting on the engine 4 exceeds the threshold value, the power from the power supply unit B is supplied from the relay box G to the first power control unit E1. At the same time, when the motor control unit 104 outputs a control signal to the first power control unit E1, the three-phase AC power from the first power control unit E1 is supplied to the generator motor M, and the generator motor M is driven. By assisting the engine rotation with force, the vehicle can run without driving power shortage and engine stoppage. When power is supplied to the generator motor M in this way, the output voltage and output of the three-phase AC power are output based on control information such as the rotational speed of the engine 4, the load value, and the amount of depression of the accelerator pedal 54. When the frequency is set and power supply from the secondary battery 59 to the first power control unit E1 is started, a large current is rapidly supplied by selecting an appropriate one from the plurality of resistors in the relay box G. To suppress inconvenience. Moreover, the problem that the large current supplied from the secondary battery 59 rapidly decreases by selecting an appropriate resistor at the time of supplying power is suppressed.

  The second power control unit E2 converts DC power into three-phase AC power at a necessary timing based on a signal from the motor control unit 104, and supplies the converted power to the first pump motor P1m and the second pump motor P2m. Perform the operation. The main control unit 101 discriminates the operation of the levers and switches, and suppresses unnecessary power consumption by driving the first pump motor P1m and the second pump motor P2m at the timing when power supply is required. It is made possible.

  INDUSTRIAL APPLICABILITY The present invention can be used not only for a work vehicle configured to travel with a driving force of only an electric motor but also for a hybrid work vehicle that travels with a driving force of an electric motor and an engine. It can also be used for other working vehicles such as lawn mowers and combines.

1 front wheel
2 Rear wheels 4 Engine
5 Transmission housing 7 Mission case 7B Internal oil passage (main oil feed passage)
7C Internal oil passage (branching oil passage 7C)
10 Lifting actuator (lifting cylinder)
36 Steering unit 38 Hydraulic filter 39 Distribution valve 59 Secondary battery A Traveling machine body B Power supply unit M Electric motor (generator motor)
P1 electric hydraulic pump / first hydraulic pump P2 electric hydraulic pump / second hydraulic pump P1m first pump motor P1p first pump P2m second pump motor P2p second pump

Claims (5)

A work vehicle that transmits a driving force of an electric motor that is operated by electric power of a power supply unit to a traveling transmission system,
A traveling machine body having a pair of left and right front wheels and a pair of left and right rear wheels is provided. The traveling machine body extends from the front side to the engine, transmission in a state extending from the front wheels to the rear wheels in the front-rear direction of the traveling machine body. A housing and a transmission case are provided in this order, and the engine is configured to transmit a driving force to the traveling transmission system and the electric motor, and the transmission case transmits the driving force of the electric motor to the traveling transmission system. Configured to communicate,
In the transmission case, an electric hydraulic pump that is operated by electric power of the power supply unit is provided on one outer side in the left-right direction located between the front wheel axle and the rear wheel axle in the front-rear direction of the traveling body. Arranged, this electric hydraulic pump is configured to suck the lubricating oil of the transmission case and supply it as hydraulic oil to the hydraulic device of the traveling machine body ,
The electric hydraulic pump is disposed at a front position on the one outer side of the transmission case, and a first hydraulic pump that supplies hydraulic oil to a steering unit that performs a steering operation of a front wheel as the hydraulic device, and a rear part thereof A work vehicle comprising: a second hydraulic pump that is disposed and that supplies hydraulic oil to an elevating actuator that performs the elevating operation of the work device at the rear of the traveling machine body as the hydraulic device . The first hydraulic pump is configured by a first pump motor that is operated by electric power and a first pump that is driven by the first pump motor, and the second hydraulic pump is driven by the second pump motor that is operated by electric power. A second pump,
The first pump is disposed at a rear position of the first pump motor, a second pump is disposed at a front position of the second pump motor, and the first pump is disposed at an intermediate position between the first pump and the second pump. Alternatively, the work vehicle according to claim 1, wherein a distribution valve that distributes and feeds hydraulic oil from the second pump is disposed . The hydraulic filter which filters the lubricating oil supplied to the said electric hydraulic pump is arrange | positioned in the other outer side on the opposite side to said one outer side in which the said electric hydraulic pump is arrange | positioned in the said mission case. The work vehicle according to 1 or 2 . The work vehicle according to claim 3, wherein an internal oil passage for sending the lubricating oil filtered by the hydraulic filter to the electric hydraulic pump is formed independently of an internal space of the transmission case . As the electric motor, one that functions as a generator is used, and the power supply unit is equipped with a secondary battery,
Charge / discharge control means for switching between a charging mode for charging the electric power generated by the electric motor to the secondary battery of the power supply unit and a driving mode for supplying electric power from the power supply unit to the electric motor. The work vehicle according to any one of claims 1 to 4 .

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