Hydraulic pump system

Abstract

To solve the problem found by the present inventors that, in a hydraulic pump system of a conventional work vehicle such as a carrot harvesting vehicle or a combine harvester, power selection between mechanical power by an engine and electric power by a motor is not always smoothly performed.SOLUTION: In a hydraulic pump system, a one-way clutch inner member 51 is connected to a main-hydraulic-pump drive shaft member 31 of a main hydraulic pump 30; a one-way clutch outer member 52 is connected to a sub-hydraulic-pump drive shaft member 41 of a sub-hydraulic-pump 40; an engine rotary shaft member 11 of an engine 10 is connected to the main-hydraulic-pump drive shaft member 31 or the one-way clutch inner member 51; and a motor rotary shaft member 21 of a motor 20 is connected to the one-way clutch outer member 52 or the sub-hydraulic-pump drive shaft member 41.SELECTED DRAWING: Figure 1

Description

[[TECHNICAL FIELD]]

[0001] The present invention relates to a hydraulic pump system for a work vehicle such as a carrot harvester vehicle or a combine harvester. [[BACKGROUND ART]]

[0002] There is known a hybrid electric vehicle equipped with an engine, a generator driven by the engine, and a traveling battery, which travels by driving a motor with electric power generated by the generator and electric power stored in the battery, the hybrid electric vehicle comprising: a traveling transmission that shifts the rotation of the motor and transmits the rotation to driving wheels; a power generation transmission that shifts the rotation of the engine and transmits the rotation to the generator; a single hydraulic pump that supplies lubricating oil to the traveling transmission and the power generation transmission; and a drive source selection mechanism that selects either the engine or the motor as a drive source for the hydraulic pump (see, for example, Patent Document 1). [[PRIOR ART DOCUMENTS]] [[PATENT DOCUMENTS]]

[0003] [[Patent Document 1]] Japanese Unexamined Patent Publication No. 7-315059 [[SUMMARY OF THE INVENTION]] [[Problem to be Solved by the Invention]]

[0004] Incidentally, the present inventor considers that, in consideration of the various needs of work vehicle users, the trend of successively implementing convenient functions in work vehicles such as carrot harvester vehicles or combine harvesters is accelerating more and more.

[0005] However, the present inventor has noticed that the usability when using convenient functions is not necessarily good in conventional hydraulic pump systems for work vehicles.

[0006] More specifically, the inventors noticed that in the hydraulic pump systems of conventional work vehicles such as carrot harvesting vehicles or combine harvesters, the power selection between mechanical power from an engine and electric power from an electric motor is not always smooth.

[0007] The present invention aims to provide a hydraulic pump system that can improve usability, taking into consideration the conventional problems described above. [Means for solving the problem]

[0008] The first aspect of the present invention is a hydraulic pump system in which engine rotational power generated by an engine and motor rotational power generated by a motor are input as driving forces, It is equipped with a main hydraulic pump, a sub-hydraulic pump, and a one-way clutch mechanism. The one-way clutch mechanism has an inner one-way clutch member and an outer one-way clutch member. The inner member of the one-way clutch is connected to the main hydraulic pump drive shaft member of the main hydraulic pump. The outer member of the one-way clutch is connected to the sub-hydraulic pump drive shaft member of the sub-hydraulic pump, The engine rotation shaft member of the engine is connected to the main hydraulic pump drive shaft member or the one-way clutch inner member. The hydraulic pump system is characterized in that the motor rotation shaft member of the motor is connected to the one-way clutch outer member or the sub-hydraulic pump drive shaft member.

[0009] The second aspect of the present invention is that the engine rotating shaft member is connected to the main hydraulic pump drive shaft member, The first hydraulic pump system of the present invention is characterized in that the motor rotating shaft member is connected to the one-way clutch outer member.

[0010] The third aspect of the present invention is that the engine rotating shaft member is connected to the main hydraulic pump drive shaft member, The first hydraulic pump system of the present invention is characterized in that the motor rotating shaft member is connected to the sub-hydraulic pump drive shaft member.

[0011] The fourth aspect of the present invention is a hydraulic pump system of the second aspect of the present invention, characterized in that the inner member of the one-way clutch is a rotating shaft member that is arranged parallel to the motor rotating shaft member.

[0012] The fifth aspect of the present invention is a hydraulic pump system according to the fourth aspect of the present invention, characterized in that the motor is driven when the hydraulic pressure of the main hydraulic pump and the sub-hydraulic pump cannot be obtained solely by the rotational power of the engine.

[0013] The sixth aspect of the present invention is that when the rotational speed of the sub-hydraulic pump drive shaft member cannot be obtained solely by the engine rotational power, the motor is driven. The fifth hydraulic pump system of the present invention is characterized in that when the rotational speed of the sub-hydraulic pump drive shaft member is obtained solely by the engine rotational power, the motor is not driven and power generation is performed.

[0014] The seventh aspect of the present invention is a hydraulic pump system of the sixth aspect of the present invention, characterized in that when the motor is not driven and power generation is being performed, and the rotational speed of the sub-hydraulic pump drive shaft member can no longer be obtained solely by the engine rotational power, the motor is driven after the magnetic field of the motor is cut off and power generation is terminated.

[0015] The eighth aspect of the present invention is a hydraulic pump system of the seventh aspect of the present invention, characterized in that when the motor is not driven and power generation is being performed, and the battery has been fully charged by the power generation, the magnetic field of the motor is cut off and the power generation is terminated. [Effects of the Invention]

[0016] According to the first aspect of the present invention, usability can be improved.

[0017] According to the second aspect of the present invention, in addition to the effect of the first aspect of the present invention, the configuration can be simplified.

[0018] According to the third aspect of the present invention, in addition to the effect of the first aspect of the present invention, the configuration can be simplified.

[0019] According to the fourth aspect of the present invention, in addition to the effect of the first aspect of the present invention, convenience can be improved.

[0020] According to the fifth aspect of the present invention, in addition to the effect of the fourth aspect of the present invention, the burden on an operator can be reduced.

[0021] According to the sixth aspect of the present invention, in addition to the effect of the fifth aspect of the present invention, reliability can be improved.

[0022] According to the seventh aspect of the present invention, in addition to the effect of the sixth aspect of the present invention, practicality can be improved.

[0023] According to the eighth aspect of the present invention, in addition to the effect of the seventh aspect of the present invention, practicality can be further improved. [BRIEF DESCRIPTION OF DRAWINGS]

[0024] [Figure 1] (a) A schematic plan view of a hydraulic pump system according to an embodiment of the present invention, (b) a schematic front view of the hydraulic pump system according to an embodiment of the present invention, (c) a schematic rear view of the hydraulic pump system according to an embodiment of the present invention [Figure 2] (a) A schematic plan view of a hydraulic pump system according to a first modification of the embodiment of the present invention, (b) a schematic front view of the hydraulic pump system according to a first modification of the embodiment of the present invention, (c) a schematic rear view of the hydraulic pump system according to a first modification of the embodiment of the present invention [Figure 3](a) A schematic plan view of a hydraulic pump system of a second modified embodiment of the present invention; (b) A schematic front view of a hydraulic pump system of a second modified embodiment of the present invention; (c) A schematic rear view of a hydraulic pump system of a second modified embodiment of the present invention. [Figure 4] (a) A schematic plan view of a hydraulic pump system of a third modified embodiment of the present invention; (b) A schematic front view of a hydraulic pump system of a third modified embodiment of the present invention; (c) A schematic rear view of a hydraulic pump system of a third modified embodiment of the present invention. [Modes for carrying out the invention]

[0025] Embodiments of the present invention will be described in detail with reference to the drawings.

[0026] The same applies below, however, some components may not be shown in the drawings, or they may be shown in perspective or in an abbreviated form.

[0027] While describing the operation of the hydraulic pump system according to the embodiment of the present invention, a hydraulic pump system operation control method related to the present invention, which is implemented by a control unit or the like, will also be described.

[0028] Such a hydraulic pump system is a specific example of the hydraulic pump system of the present invention, in which engine rotational power generated by engine 10 and motor rotational power generated by motor 20 are input as driving forces, and which has a main hydraulic pump 30, a sub-hydraulic pump 40 and a one-way clutch mechanism 50.

[0029] (1) First, the configuration and operation of the hydraulic pump system of the embodiment of the present invention will be specifically described with reference to Figures 1(a) to 1(c).

[0030] Here, Figure 1(a) is a schematic plan view of the hydraulic pump system according to an embodiment of the present invention, Figure 1(b) is a schematic front view of the hydraulic pump system according to an embodiment of the present invention, and Figure 1(c) is a schematic rear view of the hydraulic pump system according to an embodiment of the present invention.

[0031] The hydraulic pump system of the embodiment of the present invention can be realized as a dual-power hydraulic supply system by, for example, dividing a tandem hydraulic pump device.

[0032] The one-way clutch mechanism 50 has an inner one-way clutch member 51 and an outer one-way clutch member 52. The inner one-way clutch member 51 is connected to the main hydraulic pump drive shaft member 31 of the main hydraulic pump 30, and the outer one-way clutch member 52 is connected to the sub-hydraulic pump drive shaft member 41 of the sub-hydraulic pump 40.

[0033] The ability to smoothly select between mechanical power from engine 10 and electric power from motor 20 improves usability.

[0034] Power for power steering or gear changes via HST (Hydro Static Transmission) is supplied by a main hydraulic pump 30, which is a large-capacity hydraulic pump directly connected to the engine 10, while power for the lifting conveyor device of a carrot harvesting vehicle or the auger device of a combine harvester is supplied by a sub-hydraulic pump 40, which is a smaller-capacity hydraulic pump.

[0035] The engine rotation shaft member 11 of the engine 10 is connected to the main hydraulic pump drive shaft member 31 or the one-way clutch inner member 51, and the motor rotation shaft member 21 of the motor 20 is connected to the one-way clutch outer member 52 or the sub-hydraulic pump drive shaft member 41.

[0036] In the embodiments of the present invention (see Figures 1(a) to 1(c)), the engine rotating shaft member 11 is connected to the main hydraulic pump drive shaft member 31, and the motor rotating shaft member 21 is connected to the one-way clutch outer member 52.

[0037] The engine rotating shaft member 11 may also be connected to the one-way clutch inner member 51.

[0038] A one-way clutch mechanism 50, typically utilizing a cam clutch mechanism, is inserted between the main hydraulic pump 30 and the sub-hydraulic pump 40. When the engine 10 is running, both the main hydraulic pump 30 and the sub-hydraulic pump 40 can be driven by the engine rotational power generated by the engine 10. Even when the engine 10 is not running, the sub-hydraulic pump 40 can be driven by the motor rotational power generated by the motor 20.

[0039] When both the engine 10 and the motor 20 are driven, if the rotational speed of the motor rotating shaft member 21 does not exceed the rotational speed of the engine rotating shaft member 11, the one-way clutch outer member 52 does not engage with the one-way clutch inner member 51 and the sub-hydraulic pump drive shaft member 41 is driven at the rotational speed of the engine rotating shaft member 11. However, if the rotational speed of the motor rotating shaft member 21 exceeds the rotational speed of the engine rotating shaft member 11, the one-way clutch outer member 52 engages with the one-way clutch inner member 51 and the sub-hydraulic pump drive shaft member 41 is driven at the rotational speed of the motor rotating shaft member 21.

[0040] When the required rotational speed of the sub-hydraulic pump drive shaft member 41 exceeds the rotational speed of the engine rotation shaft member 11, the motor 20 is driven, and the sub-hydraulic pump drive shaft member 41 is driven at the rotational speed of the motor rotation shaft member 21. Therefore, the sub-hydraulic pump 40 is driven in response to lever operations by the first operating lever 104 and the second operating lever 105 via the motor speed controller 110. The first cylinder member 106, which is operated by the opening and closing of the first valve member 108 in response to the lever operation of the first operating lever 104, and the second cylinder member 107, which is operated by the opening and closing of the second valve member 109 in response to the lever operation of the second operating lever 105, are connected to the hydraulic circuit of the sub-hydraulic pump 40 together with the oil tank 103.

[0041] Since the so-called "run-up effect" is obtained as the engine rotation shaft member 11 rotates due to the engine's rotational power, a large rotational torque from the motor 20 for starting the motor is unnecessary, and the rotational speed of the sub-hydraulic pump drive shaft member 41 increases rapidly, exceeding the rotational speed of the engine rotation shaft member 11 as the motor 20 is driven.

[0042] After the motor 20 is driven, even after the lever operation by the first operating lever 104 and the second operating lever 105 is completed, the motor 20 is not immediately shut off but maintained. This makes it less likely that a shortage of oil flow rate to the sub-hydraulic pump 40 will occur when the lever operation is performed again.

[0043] A mode is implemented that enables a standby state in which the rotational speed of the motor 20 is automatically increased when the engine 10 is stopped or the required rotational speed of the sub-hydraulic pump drive shaft member 41 has not been achieved, and any lever operation is performed using the first operating lever 104 and the second operating lever 105.

[0044] Visualization units such as LED (Light Emitting Diode) lamps are provided on the lever heads of the first operating lever 104 and the second operating lever 105. The standby state is indicated by the lamp lighting, and the non-standby state is indicated by the lamp flashing.

[0045] When lever operations are performed simultaneously using both the first operating lever 104 and the second operating lever 105, and an increase in the oil supply flow rate of the large sub-hydraulic pump 40 is required, the rotational speed of the motor 20 is automatically increased, for example, from 2000 [rpm] to 2800 [rpm].

[0046] After the rotational speed of the motor 20 has been increased with ample margin in this manner, even when the lever operations using the first operating lever 104 and the second operating lever 105 have ended and only the first operating lever 104 is being used for single-lever operation, the high rotational speed of the motor 20, such as 2800 rpm, will be maintained for a while.

[0047] In the high-flow mode, in which the rotational speed of motor 20 is automatically increased and maintained for a period of time, if a single lever operation is performed for a predetermined period of time, the rotational speed of motor 20 is automatically reduced, for example, from 2800 rpm to 2000 rpm, in a transition to a constant-flow mode. However, when the single lever operation ends, the motor 20 is also shut off.

[0048] The inner member 51 of the one-way clutch is a rotating shaft member that is aligned parallel to the motor rotating shaft member 21.

[0049] The main hydraulic pump drive shaft member 31 penetrates the body case of the main hydraulic pump 30, and engine rotational power from the engine rotation shaft member 11 is input to the one-way clutch inner member 51 via the main hydraulic pump drive shaft member 31 with little loss.

[0050] The engine rotating shaft member 11, the main hydraulic pump drive shaft member 31, the one-way clutch inner member 51, and the sub-hydraulic pump drive shaft member 41 are aligned in a straight line, resulting in a component layout that eliminates wasted space.

[0051] The motor rotational power generated by the motor 20 is input to the one-way clutch outer member 52 via gears or sprockets and transmitted to the sub-hydraulic pump drive shaft member 41.

[0052] By not arranging the motor rotating shaft member 21 coaxially with other rotating shaft members such as the one-way clutch inner member 51, a layout is achieved that prevents the overall length of the hydraulic pump system as a unit from becoming excessive.

[0053] The motor rotating shaft member 21 is connected to the one-way clutch outer member 52 via a reduction gear. This configuration reduces the rotational speed of the motor 20, which is generally a drive unit with high rotational speed and low rotational torque, thereby increasing the rotational torque. This makes it possible to use an inexpensive motor as the motor 20, which omits the unnecessary reduction function, in order to drive the engine-driven sub-hydraulic pump 40, which often requires relatively high rotational torque.

[0054] Since at least the motor 20, the one-way clutch mechanism 50, and the sub-hydraulic pump 40 are integrated into a single unit, it is often easy to realize a specification as a so-called add-on unit.

[0055] The one-way clutch outer member 52 is connected to the sub-hydraulic pump drive shaft member 41, and by employing a so-called rigid connection for the connection of the motor 20 to the sub-hydraulic pump 40, a unit frame can be constructed without additional frame members.

[0056] By connecting the motor rotating shaft member 21 to the one-way clutch outer member 52 via a multi-stage gear or chain, a layout is achieved that prevents the outer diameter of the gear or sprocket used to input motor rotational power to the one-way clutch outer member 52 from becoming too large.

[0057] The motor 20 is driven when the hydraulic pressure of the main hydraulic pump 30 and the sub-hydraulic pump 40 cannot be obtained solely by the engine's rotational power.

[0058] The inputs and outputs of the main hydraulic pump 30 and the sub-hydraulic pump 40 are independent of each other. For example, even if the sub-hydraulic pump 40 stops due to a malfunction, there will be little adverse effect on the oil flow rate supplied to the main hydraulic pump 30.

[0059] By changing the rotational speed of the motor 20 according to the lever tilt angle of an actuator operating lever such as the first operating lever 104 or the second operating lever 105, the oil flow rate supplied to the sub-hydraulic pump 40 can be continuously changed.

[0060] The rotational speed of the motor 20 can be continuously varied within a motor speed range from a minimum motor speed to a maximum motor speed, corresponding to the practical rotational speed of the engine 10, by continuous control such as PWM (Pulse Width Modulation) control or inverter control.

[0061] For example, when the rotational speed of the engine 10 is a relatively small 1000 rpm, and a relatively large 2000 rpm is required to drive the sub-hydraulic pump 40, when motor rotational power is input from the motor rotational shaft member 21 to the one-way clutch outer member 52 in order to obtain the required rotational speed of the sub-hydraulic pump drive shaft member 41, the rotational speed of the one-way clutch outer member 52 quickly exceeds the vicinity of 1000 rpm, and the clutch on / off switching, such as cam clutch engagement and disengagement, switches smoothly and continuously, so adverse effects on the clutch life of the one-way clutch mechanism 50 are unlikely to occur.

[0062] When the rotational speed of the sub-hydraulic pump drive shaft member 41 cannot be obtained solely by the engine's rotational power, the motor 20 is driven. When the rotational speed of the sub-hydraulic pump drive shaft member 41 can be obtained solely by the engine's rotational power, the motor 20 is not driven and power generation is performed.

[0063] The rotational power generated by engine 10 is used not only to drive the main hydraulic pump 30 and the sub-hydraulic pump 40, but also to power motor 20 as a generator in a driven rotation mode.

[0064] If the required rotational speed of the sub-hydraulic pump drive shaft member 41 does not exceed the rotational speed of the engine rotation shaft member 11, the operation of the power-generating motor 20 is prohibited by electronic control or the like.

[0065] When the motor 20 is not driven and power generation is being performed, if the rotational speed of the sub-hydraulic pump drive shaft member 41 can no longer be obtained solely from the engine rotational power, the motor 20 is driven after the magnetic field of the motor 20 is cut off and power generation has ended.

[0066] For example, even when the engine 10 is idling and the rotational speed of the engine rotating shaft member 11 is insufficient, if a relatively large oil flow rate from the sub-hydraulic pump 40 is required, the motor 20 is additionally driven to replenish the sub-hydraulic pump drive shaft member 41 as needed.

[0067] When the required rotational speed of the sub-hydraulic pump drive shaft member 41 exceeds the rotational speed of the engine rotation shaft member 11, and a switch is made from the generator power generation mode to the motor drive mode, after a temporary cut-off of the magnetic field of the motor 20, power generation ends and the sub-hydraulic pump 40 is driven, accompanied by the drive of the motor 20.

[0068] Whether or not sufficient engine rotational power is being generated by the engine 10 can be determined by the direction of rotation of the motor 20's generator rotor in generator mode or the direction of the current generated by the generator.

[0069] When the motor 20 is not being driven and power generation is being performed, the magnetic field of the motor 20 is cut off and power generation ends when the battery 60 has finished being charged by the power generation.

[0070] When the motor 20 is functioning as a generator, if the battery 60 reaches a fully charged state, the charge cutoff is performed by the power generation control, thereby reducing the excess load associated with the power generation of the motor 20, and allowing the main hydraulic pump 30 and sub-hydraulic pump 40 to be driven efficiently.

[0071] If the remaining capacity of the battery 60 is insufficient, an alarm will sound and the motor 20 will be disabled.

[0072] The motor 20 is positioned so as not to interfere with the oil intake port and oil discharge port of the sub-hydraulic pump 40.

[0073] In a configuration where the sub-hydraulic pump 40 is not driven by the electric power of the motor 20, the motor 20 is removed along with a unit such as the one-way clutch mechanism 50. However, a configuration in which the sub-hydraulic pump 40 is directly connected to the main hydraulic pump 30, or a configuration in which the sub-hydraulic pump 40 is also removed and the main hydraulic pump 30 is used as a large-capacity, standalone mechanically driven pump, is conceivable.

[0074] Even in a configuration where the sub-hydraulic pump 40 is installed together with the main hydraulic pump 30, a configuration in which the main and sub-hydraulic pumps are not connected, in which power transmission between the main hydraulic pump 30 and the one-way clutch mechanism 50 is interrupted, is conceivable.

[0075] A mode is implemented in which the motor 20 is automatically started so that the sub-hydraulic pump 40 can be smoothly driven using only the electric power of the motor 20 when the engine 10's idling is stopped.

[0076] When the sub-hydraulic pump 40 is driven solely by the electric power of the motor 20, even after the lever operation using the first operating lever 104 and the second operating lever 105 is completed, the rotational speed of the motor 20, such as a standby rotational speed of 2000 rpm, is maintained for a while. After a predetermined period of time, the rotational speed of the motor 20 is gradually reduced to 1500 rpm, then 1000 rpm, and finally to 500 rpm. This makes it less likely for the rotational torque of the motor 20 to fluctuate when the motor 20 is restarted or otherwise modified.

[0077] By providing sufficient play at the point where the one-way clutch inner member 51 connects to the main hydraulic pump drive shaft member 31, it is possible to suppress oil leakage from the main hydraulic pump 30 caused by misalignment of the shaft axis.

[0078] (2) Next, the configuration and operation of the hydraulic pump system of the first modified embodiment of the present invention will be described in more detail, mainly with reference to Figures 2(a) to 2(c).

[0079] Herein, Figure 2(a) is a schematic plan view of a hydraulic pump system of a first modified embodiment of the present invention, Figure 2(b) is a schematic front view of a hydraulic pump system of a first modified embodiment of the present invention, and Figure 2(c) is a schematic rear view of a hydraulic pump system of a first modified embodiment of the present invention.

[0080] In a first modified example of the embodiment of the present invention (see Figures 2(a) to 2(c)), the engine rotating shaft member 11 is connected to the main hydraulic pump drive shaft member 31, and the motor rotating shaft member 21 is connected to the sub hydraulic pump drive shaft member 41.

[0081] The engine rotating shaft member 11 may also be connected to the one-way clutch inner member 51.

[0082] A one-way clutch mechanism 50 is inserted between the main hydraulic pump 30 and the sub-hydraulic pump 40, resulting in a simple configuration that eliminates the need for complex drive force transmission components such as Oldham couplings.

[0083] The body case of the sub-hydraulic pump 40 is securely attached to the body case of the main hydraulic pump 30 by so-called bolt-on fastening, and by inserting the one-way clutch mechanism 50 into the internal space between these two body cases, the one-way clutch mechanism 50 is not exposed to the external space and can be protected from external disturbances that affect the clutch operation.

[0084] Although the sub-hydraulic pump 40 is mechanically integrated with the main hydraulic pump 30, there is no exchange of hydraulic fluid between the main hydraulic pump 30 and the sub-hydraulic pump 40, so the discharge capacities of the main hydraulic pump 30 and the sub-hydraulic pump 40 do not affect each other.

[0085] As shown in Figures 3(a) to 3(c), for example, by eliminating the main hydraulic pump partition 113 and the sub-hydraulic pump partition 114, the number of oil inlets can be reduced, and the one-way clutch mechanism 50 can be used without so-called dry operation, while the one-way clutch mechanism 50 is oil-lubricated by the hydraulic fluid of the main hydraulic pump 30 and the sub-hydraulic pump 40.

[0086] Herein, Figure 3(a) is a schematic plan view of a hydraulic pump system of a second modified embodiment of the present invention, Figure 3(b) is a schematic front view of a hydraulic pump system of a second modified embodiment of the present invention, and Figure 3(c) is a schematic rear view of a hydraulic pump system of a second modified embodiment of the present invention.

[0087] The central shaft end of the one-way clutch outer member 52 functions as part of the gear pump shaft connected to the sub-hydraulic pump drive shaft member 41.

[0088] The central shaft end of the one-way clutch outer member 52 described above protrudes away from the one-way clutch inner member 51, serving as a shaft member for driving the sub-hydraulic pump 40.

[0089] The reduction gear between the motor 20 and the one-way clutch mechanism 50 is not inserted between the main hydraulic pump 30 and the sub-hydraulic pump 40, but is provided by utilizing the drive case 111 mounted on the back of the sub-hydraulic pump 40.

[0090] The motor 20 is mounted on the outer surface of the drive case 111, simplifying the configuration.

[0091] By utilizing the pump mounting flange 112 provided on the side to which engine rotational power is input, the motor 20, main hydraulic pump 30, sub-hydraulic pump 40 and one-way clutch mechanism 50, and drive case 111 are mounted in a stacked manner without the need for additional mounting bracket members for the sub-hydraulic pump 40 and one-way clutch mechanism 50.

[0092] Although sealing members are provided for both the main hydraulic pump 30 and the sub-hydraulic pump 40 to prevent oil leakage, the body case of the main hydraulic pump 30 firmly holds down the sealing member of the sub-hydraulic pump 40, and the body case of the sub-hydraulic pump 40 firmly holds down the sealing member of the main hydraulic pump 30, so oil leakage caused by high hydraulic pressure is almost nonexistent.

[0093] The main hydraulic pump drive shaft member 31 is provided so as to partially penetrate the one-way clutch inner member 51 and the one-way clutch outer member 52, which are sometimes called cam clutch part a and cam clutch part b, respectively, making it less likely for the one-way clutch mechanism 50 to be misaligned.

[0094] The outer end of the inner member 51 of the one-way clutch functions as the main hydraulic pump drive shaft member 31, and the outer end of the outer member 52 of the one-way clutch functions as the sub-hydraulic pump drive shaft member 41, allowing for the adoption of a so-called shaft member piercing specification.

[0095] As shown in Figures 4(a) to 4(c), for example, by employing a fixed joint member instead of the one-way clutch mechanism 50 inserted between the main hydraulic pump 30 and the sub-hydraulic pump 40, and eliminating the motor 20, a tandem hydraulic pump system can be configured in which the sub-hydraulic pump 40 is directly connected to the main hydraulic pump 30.

[0096] Herein, Figure 4(a) is a schematic plan view of a hydraulic pump system of a third modified embodiment of the present invention, Figure 4(b) is a schematic front view of a hydraulic pump system of a third modified embodiment of the present invention, and Figure 4(c) is a schematic rear view of a hydraulic pump system of a third modified embodiment of the present invention.

[0097] In addition to the normal operating mode, which involves so-called overrunning in which the outer member 52 of the one-way clutch may not engage with the inner member 51 of the one-way clutch, the system can also be configured to selectively offer an emergency operating mode using the tandem configuration described above, in case of failure of the motor 20 or the one-way clutch mechanism 50, in which the sub-hydraulic pump 40 is directly connected to the main hydraulic pump 30.

[0098] A possible configuration is one in which the connection and disconnection of engine rotational power can be switched by using the sliding of a key member or pin member that is slidably provided on the sub-hydraulic pump drive shaft member 41, which is the gear drive shaft of the sub-hydraulic pump 40, or on an inner diameter shaft member inside the sub-hydraulic pump drive shaft member 41.

[0099] A configuration is also conceivable in which the lock and unlock states of the one-way clutch mechanism 50 can be switched using a clutch switching lever or the like provided on the outer circumference of the sub-hydraulic pump 40, thereby allowing the user to choose whether or not to use a mode in which the sub-hydraulic pump 40 is directly connected to the main hydraulic pump 30.

[0100] By adopting a tandem arrangement in which the motor 20 is mounted on the sub-hydraulic pump 40, rather than being arranged in series with the main hydraulic pump 30 and the sub-hydraulic pump 40, a layout is achieved that keeps the overall unit length from becoming too large.

[0101] By filling the drive case 111 with the hydraulic fluid from the sub-hydraulic pump 40 and bringing the motor 20's housing into contact with the drive case 111, the motor 20, which tends to generate heat, can be cooled by the hydraulic fluid from the sub-hydraulic pump 40.

[0102] The rotor portion of the motor 20 is sufficiently far from the oil intake and discharge ports of the main hydraulic pump 30 and the sub-hydraulic pump 40, so that even if an oil leak occurs in the main hydraulic pump 30 or the sub-hydraulic pump 40, the motor 20 will hardly be affected by the leaked oil.

[0103] When the engine rotational power generated by the engine 10 drives the main hydraulic pump 30 and the sub-hydraulic pump 40, and the generator rotor of the motor 20 is rotating, and the battery 60 is sufficiently charged, the engine load is reduced by cutting the generator magnetic field of the motor 20.

[0104] When the generator magnetic field of motor 20 is cut off, if the motor 20 is required to act as an engine by lever operation using the first operating lever 104 and the second operating lever 105, the role of the engine is given priority.

[0105] When motor 20 is functioning as a generator, if it is required to act as an engine, the generator magnetic field is first cut off to stop the current, and then motor 20 is made to operate as an engine.

[0106] By swapping the drive gears and driven gears among the multiple transmission gears provided inside the drive case 111, and changing the rotational speed of the sub-hydraulic pump drive shaft member 41 when the sub-hydraulic pump 40 is driven using the motor 20, the so-called assist ratio can be adjusted by changing the amount of oil discharged in accordance with the unit rotation of the motor 20.

[0107] By having the sub-hydraulic pump driven shaft member 102 of the sub-hydraulic pump 40, which is positioned almost coaxially with the main hydraulic pump driven shaft member 101 of the main hydraulic pump 30, protrude toward the motor 20, the position of the gear shaft on the motor 20 side is precisely adjusted, so that shaft misalignment hardly occurs.

[0108] Furthermore, the program of the invention related to the present invention is a program that causes a computer to execute all or part of the steps (or processes, operations, and actions, etc.) of the hydraulic pump system operation control method of the invention related to the present invention described above, and is a program that operates in cooperation with the computer.

[0109] Furthermore, the recording medium of the invention related to the present invention is a recording medium that records a program for causing a computer to execute all or part of the steps (or processes, operations, and actions, etc.) of the hydraulic pump system operation control method of the invention related to the present invention described above, and is a computer-readable recording medium in which the read program is used in cooperation with the computer.

[0110] Furthermore, the "some steps (or processes, actions, and functions, etc.)" mentioned above refers to one or more of those steps.

[0111] Furthermore, the "actions of the steps (or processes, movements, and actions, etc.)" mentioned above refer to all or part of the actions of the steps mentioned above.

[0112] Furthermore, one form of use of the program of the invention related to the present invention may be that it is transmitted through a transmission medium such as the internet, light, radio waves, or sound waves, read by a computer, and operates in cooperation with the computer.

[0113] Furthermore, recording media include ROM (Read Only Memory), among others.

[0114] Furthermore, a computer is not limited to pure hardware such as a CPU (Central Processing Unit), but may also include firmware, an OS (Operating System), and even peripheral devices.

[0115] As mentioned above, the configuration of the present invention may be implemented in software or in hardware. [Industrial applicability]

[0116] The hydraulic pump system of the present invention can improve ease of use and is useful for use in hydraulic pump systems of work vehicles such as carrot harvesting vehicles or combine harvesters. [Explanation of Symbols]

[0117] 10 Engines 11 Engine Rotating Shaft Member 20 motors 21 Motor Rotating Shaft Member 30 Main hydraulic pump 31 Main hydraulic pump drive shaft member 40 Sub-hydraulic pump 41 Sub-hydraulic pump drive shaft member 50 One-way clutch mechanism 51 One-way clutch inner component 52 One-way clutch outer component 60 batteries 101 Main hydraulic pump driven shaft member 102 Sub-hydraulic pump driven shaft member 103 Oil Tank 104 First operating lever 105 Second operating lever 106 First cylinder member 107 Second cylinder member 108 First valve member 109 Second valve member 110 Motor Speed ​​Controller 111 Drive Case 112 Pump mounting flange 113 Main hydraulic pump bulkhead 114 Sub-hydraulic pump bulkhead

Claims

1. A hydraulic pump system in which engine rotational power generated by an engine and motor rotational power generated by a motor are input as driving forces, It is equipped with a main hydraulic pump, a sub-hydraulic pump, and a one-way clutch mechanism. The one-way clutch mechanism has an inner one-way clutch member and an outer one-way clutch member. The inner member of the one-way clutch is connected to the main hydraulic pump drive shaft member of the main hydraulic pump. The outer member of the one-way clutch is connected to the sub-hydraulic pump drive shaft member of the sub-hydraulic pump, The engine rotation shaft member of the engine is connected to the main hydraulic pump drive shaft member or the one-way clutch inner member. A hydraulic pump system characterized in that the motor rotation shaft member of the motor is connected to the one-way clutch outer member or the sub-hydraulic pump drive shaft member.

2. The engine rotating shaft member is connected to the main hydraulic pump drive shaft member, The hydraulic pump system according to claim 1, characterized in that the motor rotating shaft member is connected to the one-way clutch outer member.

3. The engine rotating shaft member is connected to the main hydraulic pump drive shaft member, The hydraulic pump system according to claim 1, characterized in that the motor rotating shaft member is connected to the sub-hydraulic pump drive shaft member.

4. The hydraulic pump system according to claim 2, characterized in that the inner member of the one-way clutch is a rotating shaft member that is arranged parallel to the motor rotating shaft member.

5. The hydraulic pump system according to claim 4, characterized in that the motor is driven when the hydraulic pressure of the main hydraulic pump and the sub-hydraulic pump cannot be obtained solely by the rotational power of the engine.

6. When the rotational speed of the sub-hydraulic pump drive shaft member cannot be obtained solely by the engine rotational power, the motor is driven. The hydraulic pump system according to claim 5, characterized in that when the rotational speed of the sub-hydraulic pump drive shaft member is obtained solely by the engine rotational power, the motor is not driven and power generation is performed.

7. The hydraulic pump system according to claim 6, characterized in that when the motor is not driven and power generation is being performed, and the rotational speed of the sub-hydraulic pump drive shaft member can no longer be obtained solely by the engine rotational power, the motor is driven after the magnetic field of the motor is cut off and power generation is terminated.

8. The hydraulic pump system according to claim 7, characterized in that when the motor is not driven and power generation is being performed, and the battery is fully charged by the power generation, the magnetic field of the motor is cut off and power generation is terminated.

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