JPH051170B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a vehicle deceleration energy recovery device. (Prior art) Deceleration energy (inertia energy) when a vehicle decelerates is recovered and stored in an accumulator, and the accumulated energy stored in the accumulator is transmitted to an accessory device other than the wheel drive system, such as a crane, to generate a crane. PTO (Power take)
off) Vehicle deceleration energy recovery devices with output devices are known in the prior art. (Problems to be Solved by the Invention) The conventional vehicle deceleration energy recovery device transmits the accumulated energy stored in the accumulator to an accessory device other than the wheel drive system, such as a crane, It is not used as starting energy when the vehicle starts, and its structure is complicated, so if it is used as it is, the deceleration energy (inertia energy) when the vehicle decelerates is recovered and stored in the accumulator, while the accumulated energy stored in the accumulator is used when the vehicle starts. There was a problem that it was difficult to use it as starting energy. Further, if the amount of hydraulic oil in the hydraulic circuit of the deceleration energy recovery device decreases due to leakage from a seal portion or the like, cavitation is likely to occur in the hydraulic circuit. In order to avoid this, if the amount of hydraulic oil accommodated in the oil tank is increased, the weight and accommodation space of the deceleration energy recovery device will also increase. The present invention has been made to solve the above-mentioned problems, and it collects and stores deceleration energy during vehicle deceleration without complicating the structure, and uses the stored energy as starting energy for the vehicle. It is an object of the present invention to provide a deceleration energy recovery device for a vehicle, which improves fuel efficiency, prevents cavitation by always keeping the amount of hydraulic fluid in a hydraulic circuit constant, and reduces the weight and size of the device. purpose. (Means for solving the problems) In order to achieve the above object, according to the present invention,
A transmission comprising a countershaft driven via a clutch on the engine side, a mainshaft connected to a wheel drive system, and a multi-stage gear train mechanism that transmits the rotation of the countershaft to the mainshaft in a variable speed manner; Countershaft attached to the shaft so that it can be disconnected via the countershaft PTO gear synchronizer
The PTO gear and the countershaft mesh with the PTO gear, and the main shaft is connected to the main shaft.
A multi-stage variable speed type that has a main shaft PTO gear that can be connected and disconnected via a PTO gear synchronizer, and a PTO output shaft that is driven via a drive gear meshed with the main shaft PTO gear.
a PTO output device, a pump motor connected to the PTO output shaft, a high pressure oil circuit extending from a first port of the pump motor to an accumulator, and a low pressure oil circuit extending from a second port of the pump motor to an oil tank. , a drain tank, an oil level sensor that detects the amount of hydraulic oil in the drain tank, and an oil pump that is constantly driven during engine operation,
a replenishment circuit connected to at least one of the high-pressure oil circuit and the low-pressure oil circuit, and replenishing the one circuit with hydraulic oil from the drain tank;
disposed in a supply circuit downstream of the oil pump,
An on-off valve that opens when the amount of hydraulic oil in the drain tank exceeds a predetermined value according to a detection symbol of the oil level sensor, and allows replenishment of hydraulic oil to the one circuit; There is provided a deceleration energy recovery device for a vehicle characterized by comprising a control means that functions as either a pump or a motor depending on the operating state of the vehicle. (Function) The control means of the vehicle deceleration energy recovery device of the present invention causes the pump motor to function as a pump when the vehicle is decelerated, so that the rotation of the wheels is controlled by the main shaft,
Mainshaft PTO gear, drive gear, and PTO
When the signal is transmitted to the pump/motor via the output shaft, the pump/motor sucks the hydraulic oil in the oil tank into the pump/motor from the second port of the pump/motor via the low-pressure oil circuit, Pressure is sent to the accumulator from port 1 via the high-pressure oil circuit, and the pressure is accumulated in the accumulator. Further, when the vehicle is started, the control means causes the pump motor to function as a motor, and the hydraulic oil of the accumulator that flows into the first port of the pump motor via the high pressure oil circuit drives the pump motor and then flows into the second port. The oil is returned to the oil tank from the port via the low pressure oil circuit. At this time, the rotation of the pump motor is caused by the PTO output shaft, drive gear, main shaft PTO gear, countershaft PTO gear, countershaft, speed change gear,
The hydraulic pressure is transmitted to the wheels via the main shaft, which rotates the wheels, and the hydraulic pressure stored in the accumulator is used as starting energy, improving fuel efficiency. Furthermore, when the oil level in the drain tank exceeds a predetermined value, the on-off valve opens in response to the detection signal from the oil level sensor, and the hydraulic oil in the drain tank discharged from the oil pump flows into the high-pressure oil circuit and the low-pressure oil circuit. At least one of them is replenished, oil circulation is promoted, and cavitation and early deterioration of the hydraulic oil are prevented. (Embodiment) Hereinafter, the vehicle deceleration energy recovery device of the present invention will be explained with reference to an embodiment shown in FIGS. 1 to 4. FIG. 1 shows the overall configuration of a deceleration energy recovery device, where reference numeral 1 is, for example, a diesel engine mounted on a vehicle, and the output shaft of the engine 1 includes a clutch 2, a transmission 3, a drive shaft 12a, and a differential gear 12b. through wheels 12
connected to c. The transmission 3 includes a transmission case 3a, an input shaft 19 connected to the output shaft of the engine 1 via the clutch 2, a main shaft 4, a countershaft 5, and a gear ratio to the main shaft 4. A plurality of transmission gears 17 provided correspondingly, a plurality of transmission gears 18 provided on the countershaft 5 corresponding to the transmission ratio,
and a multi-speed PTO output device (power extraction device) 3' which will be described later. The respective transmission gears 17 and 18 according to the selected transmission ratio mesh with each other to change the speed of the rotation of the engine 1 and transmit it to the wheels. Next, the main shaft PTO gear 6 of the multi-speed PTO output device 3' is loosely fitted to the output side of the main shaft 4.
A countershaft PTO gear 10 meshing with the gear 6 is loosely fitted on the output side of the countershaft 5. Further, a main shaft PTO gear synchronizer 9 and a counter shaft PTO gear synchronizer 11 are installed on each output side of the main shaft 4 and the countershaft 5, respectively. Further, a drive gear 7a that meshes with the main shaft PTO gear 6 is connected to the PTO output shaft 8 via a gear 7b. The main shaft PTO gear 6, countershaft PTO gear 10, main shaft PTO gear synchronizer 9, countershaft PTO gear synchronizer 11, PTO output shaft 8, etc. constitute a multi-speed PTO output device 3'. PTO output shaft 8 of multi-speed PTO output device 3'
is connected to a pump motor 16 via a coupling 13 and an electromagnetic clutch 14. This pump
The motor 16 has a high pressure oil passage 40 at its first port 28.
The high pressure oil passage 40 is connected to the accumulator 41 via a cutoff valve 44. These high pressure oil passages 40, cutoff valves 44, and accumulators 41
A high pressure oil circuit is constructed. The second port 29 of the pump motor 16 is connected to the low pressure oil line 42;
The low pressure oil passage 42 is connected to a pressurized oil tank 43. The low pressure oil path 42 and the pressurized oil tank 43 constitute a low pressure oil circuit. A pipe line 43a is connected to the pressurized oil tank 43, and this pipe line 43a
communicates with the air tank 45, and a solenoid valve 46 for pressurized air control, a pressure reducing valve 47, and an air dryer 48 are arranged in this order from the pressurized oil tank 43 side in the middle of the pipe line 43a. The cutoff valve 44 is an electromagnetic pilot operated valve, and is composed of an electromagnetic switching valve 80 and a logic valve 81. The logic valve 81 is provided with a valve body 81a, a spring 81b that presses the valve body 81a in the direction of closing the high pressure oil passage 40, and behind the valve body 81a,
and a pressure chamber 81c that accommodates a spring 81b. The electromagnetic switching valve 80 is, for example, a poppet valve,
When it is off (when it is in the normal position shown), the high pressure oil passage 4 on the side of the accumulator 41 from the shutoff valve 44
1st pilot oil pressure supply path 82 branching from 0
is communicated with the pressure chamber 81c of the logic valve 81,
While the logic valve 81 is turned on to shut off the high pressure oil passage 40, when it is turned on, the first pilot oil pressure supply passage 82 is shut off and the pressure chamber 81c is drained from the drain tank 55.
communicate with. Shutoff valve 44 and pump motor 16
Relief oil passage 49 branching from high pressure oil passage 40 between
extends to the pressurized oil tank 43, and the relief oil path 49 is provided with a relief valve 50, a hydraulic motor 51, and a cooler (radiator) 52 in this order from the branch side. A fan 53 is attached to the output shaft of the hydraulic motor 51, and the fan 53 blows cooling air to the cooler 52. Reference numeral 54 is a supply oil passage extending from the drain tank 55 to the high pressure oil passage 40 and the low pressure oil passage 42,
The supply oil passage 54 branches into two oil passages 54a and 54b, and one oil passage 54a is connected to the relief oil passage 49.
high pressure oil line 40 between the branch point and the pump/motor 16
The other oil passage 54b is connected to the low pressure oil passage 42, respectively. A parallel circuit 56 consisting of a check valve and a relief valve is disposed in the middle of each oil passage 54a, 54b.
a and 56b are provided, respectively. Supply oil line 54
Solenoid valve A, relief valve 57, filter 58, solenoid valve B,
An oil pump 59 and a filter 60 are arranged in this order. The solenoid valve A is a two-position switching valve, and when it is off (in the normal position shown), it shuts off the supply oil passage 54 and connects it to the oil passage 54d and the cooler 6.
1 to the drain tank 55. For example, a known gear pump is used as the oil pump 59, and the oil pump 59 is constantly driven by the engine 1 or the electric motor.
The hydraulic oil is force-fed to the replenishment oil passage 54. The solenoid valve B is also a two-position switching valve, and when it is off (in the normal position shown in the figure), it blocks the supply oil passage 54 and transfers the hydraulic oil sent from the oil pump 59 to the drain tank 55 via the oil passage 54c. circulate. Further, a relief oil passage 54e provided with a relief valve 62 is connected to the supply oil passage 54 between the branch point of the oil passages 54a and 54b and the solenoid valve A. A second pilot oil pressure supply path 63 branches from the supply oil path 54 between the relief valve 57 and the filter 58, and is connected to a solenoid valve 30 that controls the displacement of the pump motor 16. The details of the displacement control solenoid valve 30, the pump motor 16, and the piston 32 which is an actuator for driving the swash plate of the pump motor 16 will be explained with reference to FIGS. 2 to 4. The capacity control solenoid valve 30 is a 4-port servo valve, and includes a spool 31 and solenoids 35 provided at both ends of the spool 31.
a, 35b, these solenoid 35
a and 35b are connected to an electronic control unit (hereinafter referred to as "ECU") via the power connector 35.
64. The spool 31 is the ECU 6 that is supplied to the solenoids 35a and 35b.
The spool 31 moves in accordance with the control current value of the solenoid drive (energizing) signal from the solenoid 35a, 35b, and is in the neutral position shown when no drive signal is supplied to either of the solenoids 35a and 35b. Pump motor 1
Reference numeral 6 uses a variable displacement axial piston type pump and motor 16 whose rotating shaft 21 is connected to the electromagnetic clutch 14 . This rotating shaft 2
Cylinder block 25 splined to 1
A cylinder 25a is bored in the cylinder 2.
A piston 24 is slidably fitted into 5a. A shoe 23 is engaged with a spherical end 24a of the piston 24 that protrudes from a cylinder 25a. When the rotating shaft 21 rotates, the cylinder block 25 also rotates together with the rotating shaft 21, and the piston 24 moves through the shoe 23. It reciprocates within the cylinder 25a while sliding on the swash plate 22. At this time, the pump motor 16 operates as a pump or a motor depending on the tilt angle of the swash plate 22. A rod 32a fixed to a tilt angle control piston 32 is engaged with the swash plate 22, and springs 34 urge the tilt angle control piston 32 to a neutral position. A feedback mechanism 33 is provided between the tilt angle control piston 32 and the displacement control solenoid valve 30 to feed back the movement of the tilt angle control piston 32 to the spool 31 of the displacement control solenoid valve 30. Reference numerals 27a and 27b in FIG. 2 are a casing and an end block, respectively, and the end block 27b is provided with the aforementioned first port 28 and second port 29, and each port 28, 29 is connected between the end block 27b and the cylinder block 25. Suction/discharge hole 26 of valve plate 26 interposed in
It communicates with the cylinder 25a via a and 26a. Solenoid 35a of the capacity control solenoid valve 30,
35b, the spool 31 moves according to the drive signal value, and the pilot pressure oil from the pilot oil pressure supply path 63 is applied to one hydraulic surface of the tilting angle control piston 32. is sent to the hydraulic chambers 32b, 32c facing the hydraulic pressure, and the other hydraulic working surface faces the hydraulic chambers 32c, 3
The pressure oil 2b is drained, which moves the tilting angle control piston 32 and controls the tilting angle of the swash plate 22. Further, the movement of the tilting angle control piston 32 is transmitted to the spool 31 of the capacity control solenoid valve 30 via the feedback mechanism 33, whereby the spool 31 returns to the neutral position and the tilting angle of the swash plate 22 is adjusted. Controlled to the required angle value. Depending on the setting of the tilting angle of the swash plate 22, when the pump/motor 16 operates as a pump, the pump/motor 16 transfers the hydraulic oil in the pressurized oil tank 43 to the low pressure oil path 42, the second port 29, and the first port. It is fed under pressure to the accumulator 41 via the port 28 and the high pressure oil path 40. Furthermore, when the pump/motor 16 operates as a motor, the high-pressure hydraulic oil stored in the accumulator 41 is supplied to the pump/motor 16 through a route opposite to that when the pump/motor 16 operates as a pump, and is supplied to the cylinder block 25 and The rotating shaft 21 is rotated. The tilt angle control mechanism for the swash plate 22, including the feedback mechanism, is conventionally known, so a detailed explanation thereof will be omitted. The pressurized air control solenoid valve 46 and the supply oil path 54
The electromagnetic valves A and B and the electromagnetic switching valve 80 arranged in the electromagnetic switching valve 80 are both electrically connected to the ECU 64, and are supplied with drive signals D1 to D4 from the ECU 64, respectively. Also, the output side of the ECU 64 is the engine clutch 2, electromagnetic clutch 14, main and countershaft PTO gear synchronizers 9 and 1.
1, and the ECU 64 gives drive signals to these. The ECU 64 includes a stroke sensor (potentiometer, hereinafter referred to as "accelerator sensor") 65 attached to an accelerator pedal (not shown), and a stroke sensor (potentiometer (hereinafter referred to as "accelerator sensor") 65 attached to an accelerator pedal (not shown)). meter, this stroke sensor is hereinafter referred to as the "brake sensor")6
6. A clutch sensor 67 that detects engagement and disconnection of the clutch 2, a gear position sensor 68 that is attached to the speed change lever and detects the selected gear ratio of the transmission 3, and a main switch 78 of the deceleration energy recovery device are electrically connected. and each detection signal is connected to
Supplied to ECU64. Further, a pressure sensor 69 is attached to the high pressure oil passage 40 between the shutoff valve 44 and the accumulator 41, and
A pressure detection signal P is supplied to the ECU 64. A level sensor 70 for detecting the oil level is attached to the drain tank 55, and the level sensor 70 detects whether the oil level in the drain tank 55 is above a predetermined value and supplies a level detection signal L to the ECU 64. Reference numeral 77 is a charge switch attached to the driver's seat of the vehicle, for example, and when the driver desires to accumulate pressure in the accumulator 41, the charge switch 77 is turned on to give a charge command signal to the ECU 64. Furthermore, a tilt angle neutral position sensor 71 detects whether or not the tilt angle control piston 32 is in a neutral position and supplies a tilt angle neutral position signal NP to the ECU 64, and the transmission 3
A vehicle speed sensor 73 detects vehicle speed from the rotational speed of a flywheel 72 fixed to the output side end of the main shaft 4, and a main and countershaft.
The engagement states of PTO gear synchronizers 9 and 11 are detected, and synchronized feedback signals are generated respectively.
Synchro detection sensors 74 and 75 that supply MSF and CSF to the ECU 64 and a neutral sensor 76 that detects the neutral state of the transmission 3 are electrically connected to the ECU 64, respectively. The engine 1 is equipped with a fuel injection pump 84 equipped with an electronic governor 83.
is electrically connected to an electronic governor control unit 86, and its operation is electronically controlled by the electronic governor control unit 86. Then, the electronic governor control unit 86 and the
They are electrically connected to the ECU64,
The ECU 64 supplies the electronic governor control unit 86 with an accelerator signal based on the amount of depression of the accelerator pedal detected by the accelerator sensor 65 (or a pseudo accelerator signal described later) and a charge request signal described later. For example, from ECU64,
An engine rotational speed signal Ne, which is the engine rotational speed detected from the rotational speed of the camshaft of the electronic governor 83, is supplied. Reference numeral 84 is a warning light, and when the oil pressure in the high pressure oil passage 40 is below a predetermined pressure (for example, 250 kgf/cm ² ) based on the pressure detection signal P input to the ECU 64, the ECU 64 lights up a warning light 87 to issue an alarm. emits. Further, reference numeral 88 is a brake light, and when the aforementioned brake sensor 66 detects a value in which the amount of depression of the brake pedal exceeds the amount of play (for example, 10% of the total amount of depression), the ECU 64 turns on the brake light 8.
Turn on 8. Next, the operation of the deceleration energy recovery device configured as described above will be explained. The ECU 64 controls the engine clutch 2, main and countershafts based on detection signals from the various sensors mentioned above.
A drive signal is supplied to each of the PTO gear synchronizers 9 and 11 and the electromagnetic clutch 14, and the electromagnetic valve 46 for pressurized air control, the electromagnetic valves A and B, and the electromagnetic switching valve 80
A drive signal is also supplied to each of the capacity control solenoid valves 30 to operate the deceleration energy recovery device as follows. First, the ECU 64 detects the on/off state of the main switch 78, and when it is in the on state, supplies the drive signal D1 to the pressurized air control solenoid valve 46 to open the pipe 43a and release the high pressure accumulated in the air tank 45. After the air is regulated to a predetermined pressure by a pressure reducing valve 47, it is led to a pressurized oil tank 43. This makes it possible to pressurize the hydraulic oil in the oil tank 43 and prevent cavitation in the low-pressure oil passage 42. The oil tank can also be installed on the roof of a vehicle such as a bus and used as a head tank. The pressurized oil tank 44 can be installed at any position without having to do so. Furthermore, when the deceleration energy recovery device is not operating (when the engine is stopped), the solenoid valve 46
is deenergized and switched to the normal position shown in FIG. The amount of oil that leaks and flows back into the drain tank 55 can be reduced or eliminated, and the amount of oil that leaks back into the drain tank 55 can be reduced or eliminated.
capacity can be minimized. Note that the pressure reducing valve 47 disposed in the pipe line 43a is connected to the air tank 4.
The high pressure air from 5 is regulated to a predetermined pressure, and the air pressure in the pressurized oil tank 43 is kept constant. Next, the ECU 64 sets the solenoid valves A and B to the operating modes shown in Table 1 depending on the driving state of the vehicle.

[Table] When in operation stop mode, that is, pump motor 1
When valve 6 is not required to function as either a pump or a motor, ECU 64 de-energizes both solenoid valves A and B. At this time, the hydraulic oil sucked up from the drain tank 55 by the pump 59 is returned to the drain tank 55 via the oil passage 54c, and no hydraulic oil is pumped into the supply oil passage 54. or,
The hydraulic oil in the supply oil passage 54 is returned to the drain tank 55 via the deenergized solenoid valve A and the oil passage 54d. Thus, as described below, the pump motor 1
When the tilt angle control of the swash plate 22 of No. 6 is not performed, the second
This prevents unnecessary oil pressure from being generated in the pilot oil pressure supply path 63. The oil replenishment mode shown in Table 1 is set when the oil level in the drain tank 55 is above a predetermined value by the level sensor 70, and at this time the ECU 64
turns on (energizes) both solenoid valves A and B. As a result, the pump 59 causes the supply oil passage 54 to
The hydraulic oil discharged to the high pressure oil passage 40 (or the low pressure oil passage 42) is supplied to the high pressure oil passage 40 (or the low pressure oil passage 42) via the opened solenoid valves A and B and the parallel circuit 56a (or 56b). When the hydraulic oil that was being supplied to the hydraulic circuit from the accumulator 41 to the pressurized oil tank 43 in FIG. Therefore, when the oil level in the drain tank 55 exceeds the predetermined value, the high pressure oil passage 40 (or the low pressure oil passage 42) is replenished with hydraulic oil by the amount that exceeds the predetermined value.
The amount of oil in the hydraulic circuits of the pressurized oil tanks 1 to 43 can always be kept at a constant value. Next, when the pump/motor 16 should operate as a pump or a motor, the ECU 64 controls solenoid valve A to be on (energized) and solenoid valve B to be off (deenergized) in the tilt angle control mode. . This results in
In the second pilot oil pressure supply path 63, the oil pressure in the supply oil path 54 downstream of the relief valve 57, that is, the pilot oil pressure regulated to a predetermined pressure, is generated. It is supplied to a tilting angle control piston 32 via a valve 30 and used to control the tilting angle of the pump motor 16. Since the pump 59 is constantly driven by the engine 1 or the electromagnetic motor, when the tilt angle control of the pump/motor 16 is to be started, the pilot oil pressure regulated to the required pressure is immediately applied to the tilt angle control piston 3.
2 can be supplied. Furthermore, unlike the model that uses a part of the high-pressure hydraulic oil in the high-pressure oil passage 40 as pilot oil, pilot oil pressure is generated by a separately provided pump 59, so loss of high-pressure hydraulic oil (accumulated pressure energy) can be suppressed. At the same time, there is no need to provide a high pressure switching valve for guiding the pilot oil pressure from the high pressure oil passage 40, which simplifies the configuration of the hydraulic circuit. When the vehicle is running normally, the engine clutch 2 is in contact, but the electromagnetic clutch 14, main and countershaft PTO gear synchronizers 9, 1
1 is a disconnection operation, and the rotation transmitted from the engine 1 to the countershaft 5 via the clutch 2 and the input shaft 19 of the transmission 3 is transmitted to the transmission gear 1.
8, 17, and is transmitted only to the wheels 12c, 12c via the main shaft 4 and propeller shaft 12a. When the vehicle decelerates by depressing the brake pedal during normal running, the ECU 64 executes pump tilt angle control. That is, the ECU 64 is the brake sensor 66
When it detects that the brake pedal has been depressed based on a signal from The PTO gear synchronizer 11 is disconnected and the countershaft
The PTO gear 10 is released from the countershaft 5, and the rotation of the wheels 12c, 12c is transferred to the pump via the propeller shaft 12a, the main shaft PTO gear 6, the drive gears 7a, 7b, the PTO output shaft 8, the joint 13, and the electromagnetic clutch 14.・Transmit to motor 16. At this time, the ECU 64 controls the two solenoids 30a and 30b of the capacity control solenoid valve 30 so that the pump motor 16 operates as a pump and maximizes its ability as a pump.
The required drive signal D5 (or D
6) is applied to control the tilting angle of the swash plate 22 of the pump motor 16 to an optimum value, and the electromagnetic switching valve 80 of the cutoff valve 44 is energized by applying the drive signal D4, and the logic valve 81 is opened to start the pump. Pressure oil generated by the motor 16 is stored in an accumulator 41 via a first port 28 and a high pressure oil path 40. When the vehicle is stopped and the transmission 3 is in the neutral position, the driver turns on the warning light 87.
When the ECU 64 turns on the charge switch 77 after seeing the light on, the ECU 64 executes pressure charge control. This pressure charge control engages the clutch 2, disengages the main shaft PTO gear synchronizer 9, releases the main shaft PTO gear 6 with respect to the main shaft 4, and releases the main shaft PTO gear 6 from the main shaft 4.
The PTO gear synchronizer 11 is operated in contact, the countershaft PTO gear 10 is fixed to the countershaft 5, and the rotation transmitted from the engine 1 to the countershaft 5 via the clutch 2 and the input shaft 19 of the transmission is transmitted to the countershaft 5.
It is transmitted to the pump/motor 16 via the PTO gear 10, main shaft PTO gear 6, drive gears 7a, 7b, etc. At this time as well, the pump/motor 16 operates as a pump and stores pressure oil in the accumulator 41. This pressure charge control allows pressure oil to be stored in the accumulator 41, which has an insufficient amount of pressure oil, using the engine output in the idling state. Note that when pressure charge control is executed, the ECU 64 sends a charge request signal to the electronic control unit 86, and the electronic control unit 86 sends a charge request signal to the fuel injection pump 8.
4, the amount of fuel supplied to the engine 1 is controlled to increase the required amount, thereby coping with an increase in the load applied to the engine when pressure charge control is executed. When the amount of oil pumped to the accumulator 41 by the pump action of the pump motor 16 exceeds the storage capacity of the accumulator 41, the relief valve 50 opens.
The hydraulic oil is returned to the pressurized oil tank 43 via the relief oil passage 49. At this time, the hydraulic oil drives the hydraulic motor 51 disposed in the relief oil passage 49 to rotate the fan 53, and the hydraulic oil itself is also cooled as it passes through the cooler 52. Hydraulic motor 5
As described above, the fan 53 driven by the fan 53 blows air to the cooler 52 to enhance the oil cooling effect of the cooler 52. Next, when the accelerator pedal is depressed while the vehicle is stopped, the ECU 64 executes start control. This start control is performed by disengaging the main shaft PTO gear synchronizer 9 with the clutch 2 disengaged, releasing the main shaft PTO gear with respect to the main shaft 4, and engaging the countershaft PTO gear synchronizer 11. shaft
The PTO gear 10 is fixed to the countershaft 5 and the high pressure hydraulic oil stored in the accumulator 41 is guided to the pump motor 16 to drive it.
The rotation of the pump motor 16, which operates as a motor, is controlled by the electromagnetic clutch 14, the joint 13, the PTO output shaft 8,
The rotation of the main shaft 4 is transmitted to the drive gears 7b and 7a, the main shaft PTO gear 6, the countershaft PTO gear 10, the countershaft 5, the transmission gears 18 and 17, and the main shaft 4, and the rotation of the main shaft 4 is transmitted to the propeller shaft 12a and the differential gear 12b. The signal is transmitted to the wheels 12c, 12c via. In this start control, the ECU 64 uses the shutoff valve 44
The drive signal D4 is sent to the electromagnetic switching valve 80 to energize the electromagnetic switching valve 80, and the logic valve 81 is opened to supply pressure oil from the accumulator 41 to the pump motor 16. Valve 3
0, the drive signal D6 (or D5) is applied to the solenoid 30b (or 30a) different from the solenoid that applied the drive signal when the pump motor 16 is operated as a pump, and the swash plate 22 of the pump motor 16 is When operated as the pump, it is tilted in the opposite direction by an optimum tilt angle. Also, ECU
64 supplies a pseudo accelerator signal to the electronic governor control unit 86 in place of the accelerator signal from the accelerator sensor 65, and keeps the engine in an idling state even if the driver depresses the accelerator pedal while the start control is being executed. I try to keep it. Therefore, during start control, the vehicle is driven only by the driving force from the pump motor 16. The pressure oil that has driven the pump motor 16 is returned to the pressurized oil tank 43 via the second port 29 and the low pressure oil path 42. When the vehicle accelerates after starting, the ECU 64 engages the clutch 2, engages the main shaft PTO gear synchronizer 9 to fix the main shaft PTO gear 6 to the main shaft 4, and disengages the countershaft PTO gear synchronizer 11. ,
The countershaft PTO gear 10 is released from the countershaft 5, and the rotation transmitted from the engine 1 to the countershaft 5 via the clutch 2 and the input shaft 19 of the transmission 3 is transmitted to the countershaft 5 by the multi-stage transmission gears 18, 17 as usual. The rotation of the main shaft 4 is then transmitted to the propeller shaft 12a and the differential gear 12b.
The rotation of the pump motor 16, which operates as a motor, is transmitted to the wheels 12c, 12c through the electromagnetic clutch 14, the joint 13, the PTO output shaft 8, the drive gears 7b, 7a, the main shaft PTO gear 6,
It is transmitted to the wheels 12c, 12c via the main shaft 4, propeller shaft 12a, and differential gear 12b. Therefore, when the vehicle is accelerated, the vehicle is driven by the driving force of both the engine 1 and the pump/motor 16. In the above embodiment, the present invention was applied to a diesel engine.
It goes without saying that the present invention may be applied to gasoline engines. Further, although a variable displacement axial piston type pump/motor is used as the pump/motor 16 in the embodiment, it may be replaced with another type of pump/motor. (Effects of the Invention) As described in detail above, according to the vehicle deceleration energy recovery device of the present invention, the countershaft driven via the clutch on the engine side, the main shaft connected to the wheel drive system, and the countershaft are connected to the wheel drive system. A transmission having a multi-stage gear train mechanism that changes the speed and transmits the rotation of the shaft to the main shaft, and a countershaft to the countershaft.
A countershaft PTO gear that is attached to the main shaft so that it can be disconnected and disconnected via a PTO gear synchronizer, and a main shaft that meshes with the countershaft PTO gear and that is attached to the main shaft so that it can be disconnected and disconnected via a main shaft PTO gear synchronizer.
a multi-speed PTO output device having a PTO gear and a PTO output shaft driven via a drive gear meshing with the main shaft PTO gear; a pump motor connected to the PTO output shaft; A high-pressure oil circuit extends from the first port to the accumulator, a low-pressure oil circuit extends from the second port of the pump/motor to the oil tank, and the pump/motor is connected to either the pump or the motor depending on the operating state of the vehicle. Since the structure is equipped with a control means that functions as This has the effect of improving fuel efficiency by the amount of energy used for starting. Further, the drain tank includes a drain tank, an oil level sensor that detects the amount of hydraulic oil in the drain tank, and an oil pump that is constantly driven during engine operation, and is connected to at least one of the high-pressure oil circuit and the low-pressure oil circuit. A replenishment circuit is connected to the replenishment circuit for replenishing the hydraulic oil in the drain tank to one of the circuits, and a replenishment circuit is provided on the downstream side of the oil pump, and the replenishment circuit replenishes the hydraulic oil in the drain tank in response to a detection signal from the oil level sensor. It is equipped with an on-off valve that opens when the amount exceeds a predetermined value and allows the supply of hydraulic oil to the one circuit, so that the amount of hydraulic oil in the hydraulic circuit from the oil tank to the accumulator is always maintained constant. This has various effects such as promoting the circulation of the hydraulic oil, preventing cavitation and early deterioration of the hydraulic oil, and downsizing the oil tank and drain tank.

[Brief explanation of the drawing]

FIG. 1 is a hydraulic circuit diagram showing an embodiment of the vehicle deceleration energy recovery device according to the present invention, FIG. 2 is a longitudinal sectional side view of the pump/motor shown in FIG. 1, and FIG.
The figure is a longitudinal sectional front view of the capacity control electromagnetic valve of the same pump/motor, and FIG. 4 is a longitudinal sectional side view of the capacity control electromagnetic valve of FIG. 3. 1... Engine, 2... Clutch, 3... Transmission, 3'... Multi-speed PTO output device, 4... Main shaft, 5... Counter shaft, 6... Main shaft PTO gear, 7a,
7b... Drive gear, 8... PTO output shaft, 9...
Mainshaft PTO gear synchronizer, 10
... Countershaft PTO gear, 11 ... Countershaft PTO gear synchronizer, 16 ...
...Pump motor, 17, 18...Multi-stage gear train mechanism, 28...First port, 29...Second port, 30...Solenoid valve for capacity control, 32...Piston, 40...High pressure oil line , 41...Accumulator, 42...Low pressure oil line, 43...Pressurized oil tank, 54...Replenishment oil line, 59...Oil pump,
70...Level sensor, A, B...Solenoid valve (2-position switching valve).

Claims (1)

[Claims] 1. A transmission comprising a countershaft driven via a clutch on the engine side, a mainshaft connected to a wheel drive system, and a multi-stage gear train mechanism that changes speed and transmits rotation of the countershaft to the mainshaft. A countershaft PTO gear that is detachably attached to the countershaft via a countershaft PTO gear synchronizer meshes with the countershaft PTO gear and is connected to the main shaft.
A multi-stage variable speed type that has a main shaft PTO gear that can be connected and disconnected via a PTO gear synchronizer, and a PTO output shaft that is driven via a drive gear meshed with the main shaft PTO gear.
a PTO output device, a pump motor connected to the PTO output shaft, a high pressure oil circuit extending from a first port of the pump motor to an accumulator, and a low pressure oil circuit extending from a second port of the pump motor to an oil tank. , a drain tank, an oil level sensor that detects the amount of hydraulic oil in the drain tank, and an oil pump that is constantly driven during engine operation,
a replenishment circuit connected to at least one of the high-pressure oil circuit and the low-pressure oil circuit, and replenishing the one circuit with hydraulic oil from the drain tank;
disposed in a supply circuit downstream of the oil pump,
an on-off valve that opens when the amount of hydraulic oil in the drain tank exceeds a predetermined value in response to a detection signal from the oil level sensor, and allows replenishment of hydraulic oil to the one circuit; 1. A deceleration energy recovery device for a vehicle, comprising: control means for functioning as either a pump or a motor depending on the operating state of the vehicle.