JPS6239325A - Energy recovery device for reduction of vehicle speed - Google Patents

Abstract

PURPOSE:To prevent cavitation in a low pressure hydraulic circuit by configurating a device in such a way that an air pressure oil tank is connected with a hydraulic circuit in the low pressure side of a pump-motor which is connected with a PTO output shaft of a PTO output device, so as to control the pressurized air supply based on a vehicle speed. CONSTITUTION:An output shaft of an engine 1 is connected with wheels 12c by way of a clutch 2. And a multi-step transmission type PTO output device 3' which is composed of PTO gear 6 and 10 and of synchronizers 9 and 11 and the like, all of which are loosely engaged with the output side of both a main shaft 4 and a counter shaft 5, is integrally provided for a transmission 3. Then a pump-motor 16 is connected with a PTO output shaft 8 of the device 3', an accumulator 41 is connected with a high pressure hydraulic circuit 40 of the pump-motor, and an air pressure oil tank 43, to which pressurized air is supplied, is connected with its low pressure hydraulic circuit 42 through a solenoid valve 46. The solenoid valve 46 is so controlled by an ECU that it is opened when a vehicle speed is practically zero with a charge switch turned on.

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a deceleration energy recovery device that utilizes vehicle deceleration energy as starting energy. (Prior art) The deceleration energy (inertia energy) when a vehicle decelerates is recovered and stored in an accumulator, and the stored energy stored in the accumulator is transmitted to attached equipment other than the wheel drive system, such as a crane, to generate a crane. P that operates etc.
BACKGROUND OF THE INVENTION Devices for recovering deceleration energy for vehicles with a TO (1'power take off) output device are known in the 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, and uses the accumulated energy stored in the accumulator to 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 collected 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 the starting energy for the engine. In addition, if the deceleration energy of the vehicle is absorbed by the hydraulic oil in the oil tank through the low-pressure oil passage by an oil pump connected to the wheel drive system and then forced to be sent to the accumulator, cavitation will occur in the low-pressure oil passage. To avoid this, if the oil tank is installed higher than the oil pump and used as a head tank, the installation location of the oil tank will be restricted. Furthermore, if the oil tank is pressurized with pressurized air even when the deceleration energy recovery device is inactive, with the activation switch turned off, the amount of hydraulic oil leaking from the seals of the hydraulic circuit from the oil tank to the accumulator can be reduced. This causes the inconvenience of an increase in . The present invention has been made to solve the various problems mentioned above. j! By collecting deceleration energy during vehicle deceleration, storing it, and using the stored energy as starting energy for the vehicle, it aims to improve fuel efficiency. The purpose of the present invention is to provide a vehicle deceleration energy recovery device that prevents cavitation in a low-pressure oil circuit during a recovery operation, minimizes the amount of hydraulic oil used, and makes effective use of space regarding the installation location of an oil tank. . (Means for solving the problem) In order to achieve the above object, according to the present invention, a countershaft driven via a clutch on the engine side, a main shaft connected to a wheel drive system, and the countershaft are provided. a multi-stage gear train mechanism that changes speed and transmits the rotation of the main shaft to the main shaft;
A main shaft PTO gear that meshes with the TO gear and the countershaft PTO gear and is mounted on the main shaft so as to be able to communicate through a main shaft PTO gear synchronizer, and a drive gear that meshes with the main shaft PTO gear. a multi-speed PTO output device having a driven PTO output shaft; a pump motor coupled to the PTO output shaft; a high pressure oil circuit extending from a first boat of the factory pump motor to an accumulator;
a low-pressure oil circuit extending from a second boat of the motor to an oil tank; a pressurized air supply source connected to the oil tank and supplying pressurized air to the oil tank; and between the pressurized air supply source and the oil tank; An on-off valve disposed in the air passage, a vehicle speed sensor that detects vehicle speed, a control means for causing the pump/motor to function as either a pump or a motor depending on the operating state of the vehicle, and at least comprising a switch means for manually turning on and off electric power supplied to the multi-stage variable speed PTO output device and the on-off valve; Further, there is provided a vehicle deceleration energy recovery device characterized in that the on-off valve is opened when the switch means is turned on. (Function) The control means of the vehicle deceleration energy recovery device of the present invention causes the pump/motor to function as a bomb when the vehicle is decelerated, so that the rotation of the wheels is controlled by the main shaft, the main shaft PTO
When the information is transmitted to the pump motor through the gear, drive gear, and PTO output shaft, the pump motor draws the hydraulic oil in the oil tank from the second boat of the pump motor into the same pump motor, and the hydraulic oil is transferred to the pump motor. The pressure is sent from the first boat to the accumulator and the pressure is accumulated in the accumulator. Furthermore, when the vehicle is started, the control means causes the pump motor to function as a motor, and the hydraulic oil of the accumulator flowing into the first port of the pump motor drives the pump motor and then passes through the second port.
It is returned from the boat to the oil tank. At this time, the rotation of the pump motor is transmitted to the wheels via the PTO output shaft, drive gear, main shaft PTO gear, countershaft PTO gear, countershaft, transmission gear, and main shaft, and the wheels rotate to the accumulator. The accumulated hydraulic pressure is used as starting energy, improving fuel efficiency. Furthermore, the control means is configured to open and close the valve when the vehicle speed detected by the vehicle speed sensor is substantially zero and the switch means, which is an operating switch for the deceleration energy recovery device, is turned on, and the pressurized air supply source is switched on. Pressurized air is supplied to the oil tank to pressurize the hydraulic oil and prevent cavitation in the low-pressure oil circuit while the pump motor functions as a pump. (Embodiment) Hereinafter, an embodiment of the vehicle deceleration energy recovery device of the present invention will be described with reference to the drawings. FIG. 1 shows the overall configuration of a deceleration energy recovery device, in which 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, and a drive shaft 12a. and is connected to the wheel 12C via the differential value f12b. Transmission 3 is transmission case 3
a, an input shaft 19 connected to the output shaft of the engine I via the clutch 2, a main shaft 4, a counter shaft 5, and a plurality of transmission gears provided on the main shaft 4 in correspondence with transmission ratios. 17, a plurality of transmission gears 18 provided on the countershaft 5 in correspondence with transmission ratios, and a multi-speed PTO output device (power extraction device) 3°, which will be described later. The respective transmission gears 17, 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 on the output side of the main shaft 4, and the counter shaft PTO gear 10 meshing with the main shaft PTO gear 6 is connected to the counter shaft PTO gear 10, which is meshed with the main shaft PTO gear 6. It is loosely fitted on the output side of the shaft 5. Also, a main shaft PTO gear synchronizer 9 and a counter shaft PTO gear synchronizer 9 are installed on each output side of the main shaft 4 and the counter shaft 5.
A gear synchronizer 11 is installed in each case. Furthermore, 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. These main shaft PTO gear 6, counter shaft PT
O gear 10, main shaft PTO gear synchronizer 9, counter shaft PTO gear synchronizer 11,
The PTO output shaft 8 and the like constitute a multi-speed PTO output device 3'. Multi-speed PTO output device A 3° PTO output shaft 8 is connected to a pump motor 16 via a joint 13 and an electromagnetic clutch 14.
It is connected to the. This pump motor 16 is
A high pressure oil passage 4° is connected to the port 28, and the high pressure oil passage 40 is connected to an accumulator 41 via a shutoff valve 44. These high pressure oil passage 40, cutoff valve 44, and accumulator 41 constitute a high pressure oil circuit. The second boat 29 of the pump motor 16 is connected to a low pressure oil line 42 , and the low pressure oil line 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. The pressurized oil tank 43 has a pipe line 43a.
The pipe 43a is connected to the air tank 45, and in the middle of the pipe 43a, a pressurized air control voltage [1 valve 46, pressure reducing valve 47, and air dryer 48 are arranged in this order from the pressurized oil tank 43 side. It is set up. The shutoff valve 44 is an electromagnetic pyro 7) operating valve, and includes an electromagnetic switching valve 80 and a logic valve 8! It is made up of. The logic valve 81 includes a valve body 81a, a spring 81b that presses the valve body 81a in a direction to close the high pressure oil passage 40, and a valve body 81a.
A pressure chamber 8 provided behind 1a and housing a spring 81b
1c. 7M, Lil switching valve 80 is, for example, a poppet valve, and when it is off (in the normal position shown), a first pilot oil pressure supply path 82 branches from the high pressure oil path 40 on the accumulator 41 side of the cutoff valve 44.
is communicated with the pressure chamber 81c of the logic valve 81, and the logic valve 81 shuts off the high pressure oil passage 40, while when on, the first pilot oil pressure supply passage 82 is shut off and the pressure chamber 8]c is connected to the drain tank. 55. Shutoff valve 44
A relief oil passage 49 branches from the high-pressure oil passage 40 between the pump and motor 16 and extends to the pressurizing oil pump 43, and the relief oil passage 49 includes a relief valve 50, a hydraulic motor 51, and a cooler (radiator) 52 from the branch side. are arranged in this order. A fan 53 is attached to the output shaft of the hydraulic motor 51, and this fan 53 blows cooling air to the cooler 52. Reference numeral 54 is a replenishment oil passage extending from the drain tank 55 to the high pressure oil passage 40 and the low pressure oil passage 42, and the replenishment oil passage 54 branches into two oil passages 54a and 54b, one of which is the oil passage 54.
a indicates a branch point of the relief oil passage 49 and a pump motor;
The other oil passage 54b is connected to the high pressure oil passage 40 between 16 and 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. 56b are arranged respectively. The supply oil passage 54 has an oil passage 5.
Solenoid valve A and relief valve 5 from the branch point side of 4a and 54b
7. Filter 5, solenoid valve B1 oil pump 59, and filter 60 are arranged in this order. Solenoid valve A is 2
When the position switching valve is turned off (in the normal position shown in the figure), the supply oil passage 54 is shut off and communicated with the drain tank 55 via the oil passage 54d and the cooler 61. 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, and supplies the hydraulic oil from the drain tank 55 to the oil passage 5.
4. The solenoid valve B is also a two-position switching valve, and when it is off (in the normal position shown), it shuts off the supply oil passage 54 and diverts the hydraulic oil sent from the oil pump 59 to the oil passage 54.
The water is circulated to the drain tank 55 via c. Also, a supply oil path 5 between the branch point of the oil paths 54a and 54b and the solenoid valve A is provided.
4 is connected to a relief oil passage 54e provided with a relief valve 62. 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 the supply path 63 is connected to the solenoid valve 30 that controls the displacement of the pump motor 16.
is connected to. This capacity control solenoid valve 30, pump
Details of the 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 FIG. 1 and FIGS. 2 to 4. The capacity control solenoid valve 30 is a 4-boat servo valve, and has a spool 31,
Solenoids 35a provided at both ends of the spool 31;
35b, and these solenoids 35a. 35b is connected to a drive circuit 36 via a power connector 35, and this drive circuit 36 is connected to an electronic control unit (
(hereinafter referred to as rECUJ) 64. The spool 31 has solenoids 35a and 35b.
The solenoid 35a moves according to the control current value of the solenoid drive (energizing) signal from the drive circuit 36 supplied to the solenoid 35a.
, 35b, the spool 31 is in the neutral position shown. Pump motor 16
A variable displacement axial piston type pump is used, and the rotating shaft 21 of the pump/motor 16 is connected to the electromagnetic clutch 14. A cylinder 25a is bored in the cylinder block 25 which is spline-engaged with the rotating shaft 21, and a piston 24 is slidably inserted into the cylinder 25a. A shoe 23 is engaged with a spherical end 24a of the piston 24 that protrudes from the cylinder 25a, and when the rotating shaft 21 rotates, the cylinder block 25 also rotates together with the rotating shaft 2, and the piston 24 moves through the shoe 23. It reciprocates inside the cylinder 25a while sliding on the swash plate 22. At this time, depending on the tilt angle of the swash plate 22, the pump
Motor 16 will operate as a pump or motor. A rod 32a fixed to a tilt angle control piston 32 is engaged with the swash plate 22, and springs 34, 34 bias the tilt angle control piston 32 to a neutral position. Between the tilt angle control piston 32 and the capacity control solenoid valve 30, a displacement control solenoid valve 3 is provided to control the movement of the tilt angle control piston 32.
A feedback mechanism 33 is provided for feeding the 0 spool 31. Reference numerals 27a and 2 in Fig. 2
7b is a casing and an end block, respectively, and the aforementioned first boat 28 and second boat 29 are provided on the end block 27b, and each boat 28 and 29 is interposed between the end block 27b and the cylinder pro 25. It communicates with the cylinder 25a through suction/discharge holes 26a, 26a of the valve plate 26. The drive circuit 3 is connected to either the solenoid 35a or 35b of the capacity control solenoid valve 30.
When a drive signal is given from 6, the spool 31 moves according to the drive signal value, and the pilot pressure oil from the pyrosococoon pressure supply path 63 is applied to one hydraulic surface of the tilting angle control piston 32. The hydraulic chamber 32c (32b) is fed to the hydraulic chamber 32b (32c) and faces the other hydraulic working surface.
) 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 controlled by the spool 3I of the displacement control solenoid valve 30 via a feedback mechanism 33.
As a result, the spool 31 returns to the neutral position, and the tilting angle of the swash plate 22 is directly controlled to the required angle. Depending on the setting of the tilt 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/II circuit 42,
It is fed under pressure to the accumulator 41 via the second boat 29, the first boat 28, and the high pressure oil line 40. Also, pump motor 1
6 operates as a motor, the accumulator 41
The high-pressure hydraulic oil stored in the pump motor 16 is supplied to the pump motor 16 through a route opposite to that when operating as a pump, and rotates the cylinder block 25 and the rotating shaft 21. The (I11) angle turning control mechanism of the swash plate 22 including the feedback mechanism is conventionally known, so a detailed explanation thereof will be omitted. The solenoid valves A and B and the 1i magnetic switching valve 80 are both electrically connected to the ECU 64 and receive drive signals D1 to D4 from the ECU 64, respectively.
The output side of 4 is the engine clutch 2, the electromagnetic clutch 14,
It is electrically connected to the main and countershaft PTO gear synchronizers 9 and 11, respectively, and the ECU 64
gives drive signals to these. The ECU 64 includes a stroke sensor (not shown) attached to the accelerator pedal (not shown).
A potentiometer, this stroke sensor is hereinafter referred to as the "accelerator sensor J" 65, a stroke sensor (potentiometer, this stroke sensor is hereinafter referred to as the "brake sensor") 66 attached to the brake pedal (not shown), and a tarlatch valve (not shown). A clutch sensor 67 is attached to the gear shift lever (not shown) and outputs an off signal when the clutch pedal is depressed, a gear position sensor 68 is attached to the gear shift lever (not shown) and detects the selected gear of the transmission 3, and a deceleration energy recovery device. The main switches 78 that operate the are electrically connected to each other, and each detection signal is supplied to the ECU 64. A pressure sensor 69 is attached to the high pressure oil passage 40 between the cutoff valve 44 and the Akiemulator 41. 69 to E
A pressure detection signal P is supplied to the CU 64. A level sensor 70 for detecting the oil level is attached to the drain tank 55, and the acid level sensor 70 detects whether the oil level in the drain tank 55 is above a predetermined value and supplies a level detection signal to the ECU 64. Reference numeral 77 is a charge switch attached to, for example, the driver's seat of the vehicle. 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, the tilting angle control piston 32
Tilt angle neutral position sensor 71 that detects whether or not is in the neutral position and supplies a tilt angle neutral position signal NP to the ECU 64
, a vehicle speed sensor 73 that detects the vehicle speed from the rotational speed of a flywheel 72 fixed to the output end of the main shaft 4 of the transmission 3, and a vehicle speed sensor 73 that detects the engagement states of the main and countershaft PTO gear synchronizers 9 and 11. , respectively synchronized feedback signals MSF, C3
Synchro detection sensor 74.7 that supplies F to the ECU 64
Neutral sensors 76 for detecting the neutral states of the transmission and transmission systems 5 and 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. The 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. be done. The electronic governor control unit 8G and the ECU 64 are electrically connected to each other, and the electronic governor control unit 86 sends an accelerator signal (or The electronic governor control unit 86 supplies the ECU 64 with a simulated accelerator signal) and a charge request signal, which will be described later. An engine speed signal Ne is supplied. Reference numeral 84 is a warning light, and the EC is activated when the oil pressure in the accumulator 41 is below a predetermined pressure (for example, 250 kgf/c4) based on the pressure detection signal P input to the ECU 64.
U64 lights up the warning light 87 and issues a warning. Further, reference numeral 88 is a brake light (stop light), and when the brake sensor 66 described above detects that the amount of brake pedal depression exceeds a predetermined value to be described later, the ECU 64 turns on the brake light 88. Next, the operation of the deceleration energy recovery device configured as described above will be explained with reference to the program flowcharts executed in the ECU 64 shown in FIGS. 5 to 11 and FIGS. 12 to 19. The ECU 64 supplies drive signals to each of the engine clutch 2, main and countershaft PTO gear synchronizers 9.11, and electromagnetic clutch 14 based on detection signals from the various sensors described above, and supplies drive signals to the pressurized air control electromagnetic valve 46, Solenoid valves A and B,
In addition, a drive signal is supplied to each of the electromagnetic switching valves 80, a tilt angle control signal is supplied to the drive circuit 36, and a drive signal is supplied to the capacity control electromagnetic valve 30 to operate the deceleration energy recovery device as follows. Activate. First, the ECU 64 executes step 100 of the main flowchart shown in FIG. 5, and determines whether the vehicle speed is Okm/h based on the vehicle speed signal V from the vehicle speed sensor 73, that is, whether the vehicle is stopped or not. Determine. If the answer is affirmative (Yes), the process directly proceeds to step 101, where it is determined whether the main switch 78 of the deceleration energy recovery device is on or off. When the main switch 78 is in the OFF state, the ECU 64 outputs all outputs to the deceleration energy recovery device, i.e. the main and countershaft PTO gear synchronizers 9.11.
Electric clutch 14, pressurized air control solenoid valve 46, solenoid valves A and B, solenoid switching valve 80, and capacity control solenoid valve 30
A drive signal is supplied to (step 102), and step 100 is repeatedly executed until the main switch 78 is turned on in step 101. When the ON state of the main switch 78 is detected, step 104 is executed, and the ECU 64 supplies the drive signal D1 to the pressurized air control solenoid valve 46 to open the pipe line 43a.
The high pressure air accumulated in the air tank 45 is transferred to the pressure reducing valve 47.
After regulating the pressure to a predetermined pressure, the hydraulic oil is introduced into the pressurized oil tank 43. This makes it possible to pressurize the hydraulic oil in the oil tank 43, prevent cavitation in the low-pressure oil passage 42, and keep the oil tank There is no need to install it on the roof of a vehicle such as a bus and use it as a head tank.
Pressurized oil tank 44 can be installed at any position. The deceleration energy recovery device is activated for the first time when the main switch 78 is turned on when the vehicle is stopped, and the solenoid valve 46 is turned off when the deceleration energy recovery device is not activated (when the main switch 78 is turned off). Forced (
Step 102) It is switched to the normal position shown in FIG.
1, the amount of oil leaking from each seal portion of the hydraulic circuit and flowing back into the drain tank 55 can be reduced or eliminated, and the capacity of the drain tank 55 can be minimized. Note that a pressure reducing valve 47 disposed in the conduit 43a regulates the high pressure air in the air tank 45 to a predetermined pressure, and keeps the air pressure in the pressurized oil tank 43 constant. Next, the value of a flag fO, which will be described later, is set to 1 (step 105), and the process proceeds to step 106, where the vehicle speed is set to a predetermined value (for example, 6) based on the vehicle speed signal V from the vehicle speed sensor 73.
5 kIII/h) or more. When the vehicle is stopped, in step 106, the vehicle speed is 65km/h.
Of course, it is determined that the vehicle speed is below m/h, but once the vehicle starts running, if the vehicle speed becomes 65ka+/h or more, the flag is activated.

Set the 0 value to zero Step 1
07), execute step 102 to turn off all output from the ECU 64 to the deceleration energy recovery device, that is, stop the operation of the deceleration energy recovery device. This is because when the vehicle speed exceeds 55 km/h, the main and countershaft PTO gear synchronizers 9 and 11 cannot synchronize, and the rotation speed of the pump motor 16 exceeds the allowable rotation speed, so when the vehicle speed exceeds 65 km/h. If an attempt is made to recover the deceleration energy, the life of the pump/motor 16 will be adversely affected, so the operation of the deceleration energy recovery device is forcibly stopped. If the determination result in step 100 is negative (No),
That is, when the vehicle speed is equal to or higher than Qkm/h, the process proceeds to step 103, where the determination of the flag rO value is executed. Said step 107
Once the value 0 is set to the flag fO in step 103, the determination result in step 103 is always fO= until the vehicle is stopped.
O, in which case step 102 is continued. However, unless the vehicle speed becomes 65 km/h or more, the determination result in step 103 is fo=1, and in this case, step 101 will be executed. If it is determined in step 106 that the vehicle speed is 65 km/h or less, the process proceeds to step 110, and the solenoid valve AB control subroutine shown in FIG. 6 is executed. This subroutine sets the solenoid valves A and B shown in FIG. 1 to the operating modes shown in Table 1 in accordance with the driving conditions Q, 9, etc. of the vehicle. First, in step 111 of FIG.
Based on the level detection signal from the level sensor 70 attached to the drain tank 55 in FIG. 1, it is determined whether the oil level in the drain tank 55 is above a predetermined value. When the oil level in the drain tank 55 is above the predetermined value, the ECU 64 executes oil replenishment mode control and sends drive signals D2. D3 is output, and both of these solenoid valves A and B are turned on (energized) (steps 112.1], 3). As a result, the hydraulic oil discharged into the supply oil path 54 by the pump 59 is transferred to the opened solenoid valve A.
, B and the parallel circuit 56a (or 56b) to supply the high pressure oil passage 40 (or low pressure oil B42). Pressurized oil tank 4 from accumulator 41 in FIG.
If the hydraulic oil that was being supplied to the hydraulic circuit leading to No. 3 leaks from the seal part of the hydraulic circuit and is returned to the drain tank 55, the amount of oil in the drain tank 55 will increase accordingly. When the oil level exceeds the predetermined value, the accumulator 41 is replenished to the high pressure oil passage 40 (or low pressure oil passage 42) with hydraulic oil corresponding to the excess amount.
The amount of oil in the hydraulic circuit of the pressurized oil tank 43 can always be kept at a constant value. When it is determined in step 111 that the oil level in the drain tank 55 is not equal to or higher than the predetermined value, the process proceeds to step 114, where it is determined whether a charge request condition, which will be described later, is satisfied. Here, the charge request condition means that the neutral state of the transmission 3 is detected by the neutral sensor 75 shown in FIG.
According to the pressure detection signal P from the pressure sensor 69, the pressure inside the accumulator 41 is 250 kgf/at or less,
Furthermore, this refers to when the charge switch 77 provided in the driver's seat is in the on state, and when all of these conditions are met, the ECL 164 operates in the tilt angle control mode to turn on the solenoid valve A.
In this case, the drive signal D2 is turned off without outputting it.
Step 120), the drive signal D3 is supplied to the solenoid valve B to energize (turn it on) (step 121). As a result, the relief valve 5 is connected to the second pilot oil pressure supply path 63.
Hydraulic pressure in the replenishment oil passage 54 downstream of 7, that is, a pilot oil pressure regulated to a predetermined pressure is generated, and this pilot oil pressure is applied to the tilting angle control piston via the solenoid valve 30 for the capacity control 811. 32 and pump motor 16
Used for tilt angle control. 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. Also, unlike the model that uses part of the high-pressure hydraulic oil in the high-pressure oil passage 40 as pilot oil, the loss of high-pressure hydraulic oil (accumulated energy) occurs because the pyro, 1 to hydraulic pressure is generated in the pump 59, which is separately provided. In addition, there is no need to provide a high-pressure switching valve for guiding the pilot oil pressure from the high-pressure oil path 40, and the configuration of the hydraulic circuit becomes simpler. When the charge request condition in step 114 is not satisfied, the process proceeds to step 115, and it is determined based on the signal from the brake sensor 66 whether or not the brake pedal is depressed. When the amount of depression of the brake pedal is greater than zero, the process proceeds to step 116, where it is determined whether the vehicle speed is greater than Okm/h. When the vehicle speed is greater than Okn/h, that is, the brake pedal is depressed even slightly,
In addition, when the vehicle is not stopped (vehicle deceleration), steps 120 and 121 are executed to generate pilot oil pressure in the second pilot oil pressure supply path 63 in preparation for pump tilt control to be described later. When the brake pedal is depressed but the vehicle speed is Qkm/h, the ECU 64 deenergizes (off) both solenoid valves A and B by operating body stop mode.
(steps 122 and 123). At this time, that is, when the pump/motor 16 does not need to function as either a pump or a motor, the pump 59 causes the drain tank 55 to
The hydraulic oil sucked up from the drain tank 55 is returned to the drain tank 55 via the oil passage 54c, and no hydraulic oil is pumped into the replenishment oil passage 54. Further, 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 will be described later, when the tilt angle of the swash plate 22 of the pump motor 16 is not controlled, the second
This prevents unnecessary oil pressure from being generated in the pilot oil pressure supply path 63 of the pilot oil pressure supply path 63. When the amount of depression of the brake pedal is zero in step 115, the process proceeds to step 117, and the pressure sensor 69
Based on the pressure detection signal P from means that sufficient deceleration energy has not been accumulated, and in this case, steps 122 and 123 are executed to turn off both solenoid valves A and B. On the other hand, when the pressure inside the accumulator 41 reaches a predetermined level, If the value is greater than (210 kgf/c+d), the process proceeds to step 118, and each synchro feedback signal MS of the synchro detection sensors 74 and 75 in FIG.
F, main and counter shaft P based on C3F
The engagement states of TO gear synchronizers 9 and 11 are determined. In step 118, the countershaft PTO
When the gear synchronizer 11 is actuated and it is determined that the countershaft PTO gear 10 is fixed to the countershaft 5, the deceleration energy recovery device executes start control or pressure charge control when the vehicle is stopped, which will be described later. In this case, step 120
．． 121 to generate pilot oil pressure in the second pilot oil pressure supply path 63. In step 118, the main shaft PTO gear synchronizer 9 is operated to connect the main shaft PTO gear 6.
When it is determined that the accelerator sensor 6 is fixed to the main shaft 4, the process advances to step 119, and the accelerator sensor 6 in FIG.
Based on the signal from 5, it is determined whether the amount of depression of the accelerator sensor is equal to or greater than a value corresponding to 60% of the total amount of depression. When the amount of depression of the accelerator pedal is equal to or greater than 60%, this means that the deceleration energy recovery device executes the acceleration control described later, and in this case, steps 120 and 121 are executed and the second pilot Pilot hydraulic pressure is generated in the hydraulic pressure supply path 63. In step 118, if both the main and countershaft PTO gear synchronizers 9 and 11 are in the disconnected state (in the case of song black open), the process proceeds to steps 122 and 123, and both solenoid valves A and B are turned off. Returning to the main routine of FIG. 5, when the execution of the solenoid valve A-8 control subroutine is completed, the process proceeds to step 130, where it is again determined whether the vehicle speed is Q km/h, that is, whether the vehicle is stopped. do. If the vehicle is stopped, set the value of flag f2 (described later) to zero (step 131).
, the value of a flag f1, which will also be described later, is set to the value 1 (step 132), and the process proceeds to step 134. Step 13
If the determination result at 0 is negative (NO), the process proceeds to step 133, where the value of the flag f1 is determined and the flag f
If the l value is still held at the value 1 set in step 132, the process proceeds to step 134. In step 134, the selected gear of the transmission 3 is determined based on the signal from the gear position sensor 68 shown in FIG. The electromagnetic clutch 14 is disengaged without overloading, and the engine clutch drive signal DEG is output in step 136 to engage the engine clutch 2.
Proceed to step 260. Therefore, when the transmission shift lever is in the reverse position, the deceleration energy recovery device is inactivated. In step 134, when it is determined that the gear shift lever is in the neutral position, the flag f2 is
After setting the value of to zero (step 137), step 1
At step 38, the on/off state of the churn switch 77 is determined. If the charge switch 77 is off, steps 135 and 136 are executed, and the deceleration energy recovery device is deactivated. In step 138, if the charge switch 7 is on, step 1 is performed.
39, based on the pressure detection signal P of the pressure sensor 69, the pressure in the accumulator 41 reaches a predetermined pressure (for example, 25
0kgf/cd) or less. The pressure inside the accumulator 41 is set to the predetermined pressure (250 kg).
f/cm) or more, the deceleration energy is sufficiently stored in the accumulator 41, and it is determined that there is no need to accumulate pressure in the accumulator 41 by executing pressure charge control, which will be described later, and steps 135 and 136 are performed. Execution disables the deceleration energy recovery device. On the other hand, if it is determined in step 139 that the pressure inside the accumulator 41 is below the predetermined pressure (250 kgf/c4), all of the charge request conditions described above are satisfied, and the process proceeds to step 140, where the ECU 64 executes the pressure charge control subroutine. Execute. FIG. 7 is a flowchart of the pressure charge control subroutine executed by the ECU 64. First, in step 141, the clutch sensor 67 shown in FIG. Discern. When the driver disengages the engine clutch 2 (off), step 14
Proceeding to step 2, the ECU 64 outputs a pump tilt angle control signal to the drive circuit 36 to 0■, and does not output a drive signal from the drive circuit 36 to any of the solenoids 30a and 30b of the capacity control solenoid valve 30. Holding the spool 31 of the capacity control solenoid valve 30 at the neutral position shown in the figure, and turning off a charge request signal to the electronic governor control unit 86 to be described later (step 143), further supplying the 1i magnetic clutch drive signal DCR The electromagnetic clutch 14
is turned off (step 144). On the other hand, if the engine clutch 2 is on (engaged) in step 141, the process advances to step 145 and EC!
J64 temporarily stops the supply of the engine crunch drive signal DEC to the engine clutch 2 and disengages the clutch 2, and then also stops the supply of the synchro drive signal MSD to the main shaft PTO gear synchronizer 9, so that the main shaft PTO gear The synchronizer 9 is turned off (step 146). Then, the ECU 64 determines whether or not the main shaft PTO gear synchronizer 9 has reliably completed the disconnection operation based on the synchro feedback signal MSF from the synchro detection sensor 74, and the disconnection operation of the main shaft PTO gear synchronizer 9 has been completed. Wait until the main shaft P (step 147)
When the disconnection operation of the TO gear synchronizer 9 is completed and the main shaft Pro gear 6 is released from the main shaft 4, the process proceeds to step 148, where the ECU 64 sends a synchronization drive signal C3D to the counter shaft p"ro gear synchronizer 11. In this case as well, the ECU 64 determines whether or not the countershaft PTO gear synchronizer IL has reliably completed the contact operation based on the synchro feedback signal C3F from the synchro detection sensor 75, and Wait until the contact operation of the PTO gear synchronizer 11 is completed (step 149). Then, the counter shift PTO gear synchronizer 1
1 contact action (on) is completed and the countershaft PTO
When the gear 10 is fixed to the counter shaft 5, the electromagnetic clutch drive signal DCR is supplied to the electromagnetic clutch 14 to turn on the electromagnetic clutch 14 (step 15).
0), ECL! 64 is an electronic control unit 86
A charge request signal is sent to the electronic governor control unit 86 to control the fuel injection pump 84 to increase the required amount of fuel supplied to the engine 1 (step 151). This copes with an increase in the load placed on the engine 1 due to the operation of the pump motor 16, which will be described later, in pressure charge control. Next, the ECU 64 resumes supplying the engine clutch drive signal DEC to the engine clutch 2, turns on the engine clutch 2 (step 152), and then outputs a pump tilt signal having a predetermined positive voltage value. A rotation control signal is sent to the drive circuit 36 to set the tilt angle of the swash plate 22 of the pump motor 16 to an optimal value for the pump motor 16 to operate as a pump (step 153); 154, the pressure within the accumulator 41 is determined, and the pressure within the accumulator 41 reaches the predetermined value (250
kgf/cJ) or less, step 140 in FIG.
Return to Therefore, this pressure charge control subroutine is repeatedly executed while the above charge request condition is satisfied. In this way, as shown by the large broken line in FIG.
The rotation transmitted from the clutch 2 to the countershaft 5 via the input shaft 19 of the transmission is transmitted to the countershaft PTO gear 10. Main shaft PTO gear 6,
It is transmitted to the pump motor 16 via the drive gears 7a, 7b, the PTO output shaft 8, the joint 13, and the electromagnetic clutch 14,
At this time, the pump motor 16 that operates as a pump stores pressure oil in the accumulator 41 via the first boat 28 and the high pressure oil line 40. When the driver turns on the charge request switch 77 provided on the driver's seat, pressure oil can be stored in the Akie emulator 41, which has an insufficient amount of pressure oil, using the engine output in the idling state through this pressure charge control. . In the step 154, when it is determined that the pressure in the accumulator 41 exceeds the predetermined pressure (250 kgf/cat), the steps 142 to 144 are executed to disable the deceleration energy recovery device, and the pressure charge control is performed. Terminates execution of the subroutine. Step 1 in Figure 5 from the pressure charge control subroutine
When the process returns to step 40, the process proceeds to step 260, where it is again determined whether the pressure within the accumulator 41 is below a predetermined pressure (250 kgf/c11), and if the pressure within the accumulator 41 is below the predetermined pressure, the process shown in FIG. The warning light 84 is turned on (step 261), and if the pressure is higher than a predetermined pressure, the warning light 84 is turned off (step 262).This allows the driver to know the state of accumulation of deceleration energy in the accumulator 41. In step 134, the gear shift lever is set to 2.
If it is determined that the vehicle is in any position from speed to fifth speed, the process proceeds to step 160, where the value of flag f2 is determined. This flag "2" is used to determine whether or not the start control subroutine described later has already been executed, and when the vehicle is in a gray stop state, the flag r2 value is set to the value 0 set in step 131. Therefore, in such a case, the process proceeds to step 161, and the accumulator 41
It is determined whether the internal pressure is below a predetermined pressure (250 kgf/cal). If the pressure in the accumulator 41 is equal to or higher than the first predetermined pressure (250 kgr/d>) by this determination, the flag f2 is set to the value 1 (step 162),
Execute the start control subroutine to be described later (step 1)
70). In step 162, the flag f2 is set to a value of 1.
is set, the ECU 64 skips steps 161 and 162 and directly proceeds to step 170, based on the determination in step 1.60, to execute the start control subroutine. That is, if the pressure in the 7 accumulator 41 is equal to or higher than a predetermined pressure (250 kgf/cd) immediately before the vehicle starts, the start control subroutine described later is executed, and once this subroutine is executed, the pressure in the sheet metal accumulator 41 reaches the predetermined pressure (250 kgf/cd). /c+a) or below, the subroutine will continue to be executed. FIG. 8 shows a flowchart of the start control subroutine. First, in step 1-71, the selected gear of the transmisciran 3 is determined based on the signal from the gear sensor 68, and the gear shift lever is set to 4th and 5th gear. When the vehicle is in either the 4th or 5th gear position, the ECU 64 does not output the engine clutch drive signal DEC and disengages the clutch 2 (step 172). If a gear stage, that is, a gear stage inappropriate for starting, is selected, it will be difficult to start, so the clutch 2 is disengaged and the deceleration energy recovery device is disabled without any activation operation. Leave activated and return to main routine. In step 171, transmisosilane 3 is
When it is determined that the vehicle is in the vehicle speed position, the vehicle speed Vo, which will be described later, is determined.
The vehicle speed Vo value is set to a first predetermined value (for example, 5 km/h) (step 173), and when it is determined that the vehicle is in the third gear position, the shift vehicle speed Vo value is set to a second predetermined value (for example, 101 tm/h).
(step 174), and the process proceeds to step 175. In step 175, the vehicle speed signal from the vehicle speed sensor 73 is
The vehicle speed (Vo) detected based on the above is compared with the variable speed vehicle speed Vo set in either of steps 173 and 174. This variable speed vehicle speed 0 is used to determine whether to drive the vehicle only by deceleration energy or by the output of the engine 1 in addition to deceleration energy (the latter is referred to as "acceleration control") when the vehicle starts.
As a result of the comparison, if the vehicle speed (2) is greater than or equal to the shift vehicle speed Vo, the process proceeds to step 187, where a shift control subroutine to be described later, which is a pre-operation for executing acceleration control, is executed. In step 175, if the vehicle speed is less than or equal to the shift vehicle speed Vo, the process proceeds to step 176, where the ECU 64 temporarily stops supplying the engine clutch drive signal DEC to the engine clutch 2, disengages the clutch 2, and then switches the main shaft PTO gear. fMM of the synchro drive signal MSD to the synchronizer 9 is also stopped, and the main shaft PTO gear synchronizer 9 is turned off (step 1).
77). Then, the ECU 64 receives a synchro feed bank signal MS from the synchro detection sensor 74 to determine whether the main shaft PTO gear synchronizer 9 has reliably completed the disconnection operation.
F, and waits until the disconnection operation of the main shaft PTO gear synchronizer 9 is completed (step 178).
). When the disconnection operation of the main shaft PTO gear synchronizer 9 is completed and the main shaft PTO gear 6 is released from the main shaft 4, the process advances to step 179, and E
The CU64 sends a synchro drive signal C3D to the countershaft PTO gear synchronizer 11 and activates it (
turn on. In this case as well, the ECU 64 determines whether or not the countershaft PTO gear synchronizer 11 has reliably completed the contact operation based on the synchro feedback signal C5F from the synchro output sensor 75. The process waits until the first contact operation is completed (step 180). Next, counteryaft PTO gear synchronizer 1
1 contact action (on) is completed and the countershaft PTO
Once the gear 10 is fixed to the countershaft 5, the process proceeds to step 181, where it is determined based on the signal from the accelerator sensor 65 whether the amount of depression of the accelerator pedal is greater than zero. If it is determined that the amount of depression of the accelerator pedal is greater than zero, this means that the vehicle is in a starting state, and if the accelerator pedal is pressed, the process proceeds to step 188, where a motor tilt control subroutine is executed. FIG. 9 shows a flowchart of the motor tilting control subroutine. First, in step 221, the pressure in the accumulator 41 is reduced to a second predetermined pressure (for example, 210 kgf/
It is determined whether or not the value has decreased below cI+. The pressure inside the accumulator 41 is the second predetermined pressure (210 kgf
/cJ), the hydraulic oil will no longer be able to generate sufficient driving force to drive the pump motor 16 to start and accelerate the vehicle. In such a case, the process advances to step 222 and the above-mentioned speed change control is executed. If it is determined in step 221 that the pressure inside the accumulator 41 is equal to or higher than the second predetermined pressure (210 kgf/cI+), the process proceeds to step 223, and the ECLI 64 outputs a motor tilt angle control signal to the drive circuit 36. Note that the second predetermined value, which is the discrimination value in step 221, may be set to different values depending on whether the pressure changes in an increasing direction or in a decreasing direction, in order to stabilize the control. The output value of the motor tilt angle control signal is set based on each detection signal from the accelerator sensor 65 and the synchro detection sensor 74 and 75 shown in FIG. 1.
4 is a graph showing an example of the relationship between the output value of the motor tilt angle control signal outputted from 4 and the depression M (accelerator opening degree) of the accelerator pedal. The rotation control signal value gradually changes from the atmosphere to the negative direction as the accelerator opening increases from the first predetermined value (for example, 40%) along the straight line shown by the solid line in the figure. The output value is set to a negative predetermined value (2), 4 (for example, a predetermined value between -3V and -5V) that provides the maximum motor capacity when the accelerator opening degree is 100%. Main shaft P
When the TO gear synchronizer 9 is in the contact operation, the opening starts when the accelerator opening reaches a second predetermined value (for example, 60%) that is larger than the first predetermined value, along the straight line shown by the broken line in FIG. As the degree value increases, the output value is gradually decreased from zero in the negative direction, and when the accelerator opening degree is 100%, the output value is set to the negative predetermined value (2). It is set to reach. Two solenoids 35a of the capacity control solenoid valve 30 according to the motor tilt angle control signal value supplied to the drive circuit 36,
35b, the capacity control solenoid valve 30 sends the pilot hydraulic pressure generated in the second pilot hydraulic pressure supply path 63 to the piston 32, displacing the piston 30, and thereby displacing the piston 30. Pump motor 1
The tilt angle of the swash plate 6 is controlled to the optimum value for motor operation at the time of starting. Next, the process proceeds to step 224, where the synchronization detection sensor 7
4.75 each synchronized feedback signal MSF, C3
The engagement states of the main and countershaft PTO gear synchronizers 9 and 11 are determined based on F. 8th
When the motor tilt control is executed in the start control shown in the figure, in step 224 the countershaft PT
It should be determined that the O gear synchronizer 11 is operating in contact, and in this case, the process proceeds to step 225 and the ECU 6
4 supplies a pseudo accelerator signal to the electronic governor control unit 86, which instructs the fuel injection pump 84 to inject the amount of fuel necessary to maintain the engine in an idling state, regardless of the amount of depression of the accelerator pedal by the driver. Control j1 to supply injection to engine l. And step 2
26, it is determined whether the amount of depression of the accelerator pedal is equal to or greater than the first predetermined value (40%). The first predetermined value, which is this discrimination value, is also set to a different value depending on whether the accelerator pedal depression amount changes in an increasing direction or in a decreasing direction, in order to stabilize the control, so as to have hysteresis characteristics. As a result of the determination in step 226, if the amount of depression of the accelerator pedal is greater than or equal to the first predetermined value,
64 outputs the electromagnetic clutch drive signal DCR to the electromagnetic clutch 14.
and turn it on (step 227).
), then the electromagnetic switching valve (Bopé 7 valve) of the shutoff valve 44) 80
The drive signal D4 is applied to the logic valve 81 to open the logic valve 81 (step 228). In this way, the high-pressure hydraulic oil stored in the Akiemulator 41 is transferred to the pump/motor 16.
The rotation of the pump motor 16, which operates as a motor, is guided by the electromagnetic clutch 14, the joint 13, the PTO output shaft 8, the drive gears 7b and 7a, and the main The rotation of the main shaft 4 is transmitted to the shaft PTO gear 6, countershaft PTO gear 10, countershaft 5, transmission gears 18, 17, and main shaft 4, and further, the rotation of the main shaft 4 is transmitted to the wheels 12c, 12c via the propeller shaft 12a and differential gear 12b. communicated. Note that the hydraulic 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. In this way, during start control when sufficient deceleration energy is stored in the accumulator 41, the vehicle is driven only by the driving force from the pump motor 16, and the rotation of the pump motor 16 is controlled by the transmission. The gears 17 and 18 are interposed between the main shaft 4 and the countershaft 5 of 3, and the wheels 12C are shifted according to the gear ratio selected according to the load condition B (load) of the vehicle. , 12C, optimum starting performance can be obtained. If it is determined in step 226 that the amount of depression of the accelerator pedal is less than the first predetermined value (40%), for example, when attempting to start the vehicle, the amount of depression of the accelerator pedal is insufficient. If the accelerator pedal is released or the accelerator pedal is released during starting acceleration, the process advances to step 229 and the first
Based on the tilt angle neutral position signal NP from the tilt angle neutral position sensor 71 shown in the figure, it is determined whether the piston 32 is in the neutral position, that is, the tilt angle of the pump motor 16 Fi, 22 is zero. do. The amount of depression of the accelerator pedal is the first predetermined value (
40%), the tilt angle control signal output value output from the ECU 64 to the drive circuit 36 is set to zero as shown in FIG. There is no problem if the amount of depression of the accelerator pedal is originally less than the first predetermined value (40%), but if the accelerator pedal is returned and becomes less than the first predetermined value, there is a response delay in the hydraulic circuit. Therefore, even if the tilt angle control signal output value from the ECU 64 becomes zero, the tilt angle of the swash plate 22 of the pump motor 16 does not immediately become zero. Electromagnetic clutch 14 is disconnected (off) even though the tilting angle is not zero
If the high-pressure oil circuit 40 is shut off (poppet valve 80 turned off), vibrations and accompanying noise will occur in the hydraulic circuit, which is undesirable. Therefore, when it is determined in step 229 that the tilt angle is not yet zero (if the determination result in step 229 is negative (NO)), step 188 in FIG. Therefore, the process returns to step 170 in FIG. Then, in step 229, it is confirmed that the tilt angle has been returned to zero (the determination result in step 229 is affirmative (Y
es)), proceed to step 230 and proceed to electromagnetic clutch 1
4 is turned off, and in step 231, the electromagnetic switching valve (poppet valve) 80 of the cutoff valve 44 is deenergized (off) to close the logic valve 81 and deactivate the deceleration energy recovery device. If it is determined in step 181 of FIG. 8 that the amount of depression of the accelerator pedal is zero, for example, if the vehicle is in a state immediately before starting, or if the accelerator pedal is completely returned during starting acceleration, The ECU 64 sets the output value of the motor tilt angle control signal to the drive circuit 36 to zero, thereby returning the tilt angle of the swash plate 22 of the pump motor 16 to zero (step 182). After confirming that the tilt angle of the swash plate 22 has become zero (step 183), the electromagnetic switching valve (poppet valve) 80 of the cutoff valve 44 is deenergized (off), and the logic valve 81 is closed. Then, based on the signal from the brake sensor 64 shown in FIG. 1, it is determined whether or not the brake pedal depression amount is zero (185). If the amount of depression of the brake pedal is zero, the electromagnetic clutch 14 is disengaged (off) to stop the operation of the deceleration energy recovery device (step 186), and the process returns to the main routine shown in FIG. Further, if the accelerator pedal is released and the brake pedal is depressed during starting acceleration when the vehicle speed V has not yet reached the shift vehicle speed Vo, the process proceeds to step 189 as a result of the determination in step 185, and pump tilt control, which will be described later, is executed. Even in such cases, the vehicle's deceleration energy can be recovered. When vehicle speed V exceeds shift vehicle speed Vo during start acceleration (No. 8
Step 1 executed by the determination in step 175 in the figure
87), and when the pressure in the accumulator 41 at the start of the start is below the first predetermined pressure (250 kgf/cj) (step 190 executed based on the determination in step 161 in FIG. 5), the above-mentioned shift control is performed. The vehicle is driven not only by the driving force from the pump motor 16 but also by the driving force from the engine 1 by the acceleration control which is executed following this speed change control. FIG. 10 shows a flowchart of the speed change control subroutine. First, in step +91, the ECU 64 sets the output value of the motor tilt angle control signal to the drive circuit 36 to zero to return the tilt angle of the swash plate 22 to zero. . Next, ECLJ64 outputs the Enson clutch drive signal DE.
C is output to engage the engine clutch 2 (step 192), and then waits for a predetermined time (for example, 0.1 seconds) to elapse, that is, waits for the engagement of the engine clutch 2 to be completed (step 193). , supplies the true accelerator signal from the accelerator sensor 65 to the electronic governor control unit 86 (step 7'194). The electronic governor control unit 86 receives a pseudo accelerator signal from the ECU 64 during start control (step 18 in FIG. 8).
Step 7 225 of the motor tilt control subroutine executed in step 8) The fuel injection pump 84 was injecting and supplying the engine 1 with the amount of fuel necessary to maintain the engine 1 in the idle state, but when the ECU 64 When the signal is received, the amount of fuel in the engine is adjusted according to the amount of depression of the accelerator pedal.
The fuel will be supplied by injection. The reason why the ECU 64 waits for the completion of the engagement operation of the engine clutch 2 and then gives a true accelerator signal to the electronic governor control unit 86 is to prevent the engine 1 from revving up. Next, in step 195, after waiting until the tilt angle of the swash plate 22 of the pump motor 16 becomes zero, the shutoff valve 44 is closed.
The electromagnetic switching valve (poppet valve) 80 is deenergized (off), the logic valve 81 is closed (step 196), the electromagnetic clutch 14 is disengaged (off) (step 197),
Temporarily stop the operation of the deceleration energy recovery device. Then, in steps 198 to 201, the countershaft PTO gear synchronizer 11, which is in contact operation, is turned off, while the main shaft PTO gear synchronizer 9 is switched to contact operation. More specifically, in step 198, the ECU 64 controls the countershaft PTO.
Synchro drive signal C'SD to gear synchronizer 11
The counter shaft PTO gear synchronizer 11 is turned off (step 198).
). Then, the ECU 64 determines whether or not the countershaft PTO gear synchronizer 11 has reliably completed the disconnection operation based on the synchronization feedback signal C3F from the synchronization detection sensor 75, and waits until the disconnection operation of the countershaft PTO gear synchronizer 11 is completed. (Step 199), the disconnection operation of the countershaft PTO gear synchronizer 11 is completed and the countershaft PTO
When the gear 10 is released from the countershaft 5, the process proceeds to step 200, and the ECU 64 releases the main shaft PT.
A synchro drive signal MSD is sent to the O gear synchronizer 9 to turn it on. In this case as well, ECU6
4 determines whether or not the main shaft PTO gear synchronizer 9 has reliably completed the contact operation based on the synchro feedback signal MSF from the synchro detection sensor 74;
The main shaft PTO gear synchronizer 9 waits until the contact operation of the main shaft PTO gear synchronizer 9 is completed (step 201). Next, when the contact operation (on) of the main shaft PTO gear synchronizer 9 is completed and the main shaft PTO gear 6 is fixed to the main shaft 4, the process proceeds to step 202, where the value 0 is set to the aforementioned flag fl and the fifth Return to the main routine shown in the figure. When the speed change control subroutine is executed, the driving force of the engine l is transferred to the wheels 12c,
12c and the driving force of the pump motor 16 is transmitted to the wheels 12c, 12C, a path shown by the large broken line in FIG. 18 is established. More specifically, 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 main shaft 4 after being changed in speed by a multi-stage transmission gear 18, 17 in the usual manner. The rotation of the main shaft 4 is the propeller shaft 12a, differential bag! Wheel 12c via 12b
, 12c, while the pump motor 16, which operates as a motor, connects the electromagnetic clutch 14, the coupling 13, and the PTO
Output shaft 8, drive gears 7b, 7a, main shaft PTO
gear 6, main shaft 4, propeller shaft 12a,
and the wheels 12c, 12c via the differential gear 12b. As a result, in the main routine of FIG. 5, the determination result at step 130 is negative (No), that is, the vehicle speed is not Okm/h, and the flag fl value is determined to be zero at step 133, and the process proceeds to step 210. It turns out. Furthermore, once the shift control is executed even once after the vehicle starts, the flag fl value remains at the value O until the vehicle stops.
Therefore, the steps after step 210 are executed every time the main routine is executed. In step 210, the ECU 64 supplies the electronic governor control unit 86 with the true accelerator signal from the accelerator sensor 65. As a result, the electronic governor control unit 86 causes the fuel injection pump 84 to inject and supply an amount of fuel to the engine l according to the amount of depression of the accelerator pedal. Next, it is determined whether the amount of depression of the accelerator pedal is zero (step 211), and if it is not zero, the engine clutch 2 is engaged (step 214), and the motor tilt control subroutine of step 220 is executed. The motor tilting control subroutine shown in FIG. 9 is executed again.
After confirming in step 221 that the pressure inside the accumulator 41 is equal to or higher than the second predetermined pressure (210 kgf/cd), the process proceeds to step 223, where the ECU 6
4 is the accelerator pedal depression! The output value of the motor tilt angle control signal is set according to the accelerator opening degree and is supplied to the drive circuit 36. At this time, as described above, the main shaft PTO gear synchronizer 9 is in contact operation (ON) due to execution of the speed change control subroutine, so the output value of the motor tilt angle control signal is set along the broken line shown in the 12th time. . As is clear from FIG. 12, the motor tilt angle control signal output value during acceleration control, and therefore the tilt angle of the swash plate 22 of the pump motor 16, is set to a smaller value than during start control for the same accelerator opening. Therefore, the motor capacity of the pump motor 16 is set to be small, and the load on the pump motor 16 is reduced. As a result, the transmission path of the driving force from the pump motor 16 to the wheels 12C, 12C is the path from the countershaft 5 to the main shaft shown in FIG. Even if the transmission path is changed from the path in which the gear is changed and transmitted to the path shown in FIG. 18 in which the transmission is directly transmitted to the main shaft 5, the switching can be smoothly performed without sudden torque fluctuations or vibrations. Next, in step 224, the main shaft P
When it is determined that the TO gear synchronizer 9 is in contact, the process proceeds to step 232, where the determination value is 0, which determines whether the amount of depression of the accelerator pedal (accelerator opening) is equal to or greater than the second predetermined value (60%). In order to stabilize the control, the second predetermined value may also be set to a different value depending on whether the amount of depression of the accelerator pedal changes in an increasing direction or in a decreasing direction, so as to have a hysteresis characteristic. If the amount of depression of the accelerator pedal is equal to or greater than the second predetermined value, step 233
In step 234, the electromagnetic clutch 14 is engaged and the electromagnetic switching valve (poppet valve) of the cutoff valve 44 is activated.
81 is energized. The sick valve 81 is opened. As a result, the rotation of the pump/motor 16 is transmitted to the wheels 12C, 12C via the path indicated by the large broken line shown in FIG. will be done. If it is determined in step 232 that the amount of depression of the accelerator pedal is less than or equal to the second predetermined value (60%), the process proceeds to step 229. At this time, since the motor tilt angle control signal output value is set to zero in step 223 (broken line in Figure 12)
, the tilt angle of +5.22 of the pump motor 16 changes to zero, but as described above, wait until the tilt angle of this swash plate 22 becomes zero, and then disengage the electromagnetic clutch 14 and disconnect it. The electromagnetic switching valve (poppet valve) 80 of the valve 44 is deenergized (off) to disable the deceleration energy recovery device (steps 229 to 231). Therefore, in such a case, the vehicle will be driven only by the driving force of the engine 1 (FIG. 14). Further, during the execution of the motor tilting control, the accumulated pressure energy in the accumulator 41 is consumed and the pressure decreases to the second predetermined pressure (2
10 kgf/e+7) or less, the above-mentioned speed change control will be executed repeatedly (step 222 in FIG. 9), and in this case as well, the vehicle will be driven only by the driving force of the engine 1. . Next, when the vehicle is in a steady running state, the accelerator pedal is depressed by the required amount;
After the determination in step 211 in the figure, the process proceeds to step 220, where a motor tilting control subroutine is executed. but,
When the vehicle is in steady running condition, the ECU 64 controls the main and countershaft PTO gear synchronizers 9 and 1.
1 are both in disconnection mode (synchronized open), and the 9th
Step 235 is executed based on the determination in step 224 in the figure. In step 235, the ECU 64 sets the output value of the motor tilt angle control signal to the drive circuit 36 to zero, thereby returning the tilt angle of the swash plate 22 of the pump motor 16 to zero. Then, similarly to steps 229 to 231, it is determined whether the tilt angle of the swash plate 22 has become zero, and if the final tilt angle is not zero, steps 237 and 238, which will be described later, are skipped and the main routine is executed. Return to When the tilt angle becomes zero, the electromagnetic clutch 14 is disengaged and the electromagnetic switching valve (poppet valve) 81 of the cutoff valve 44 is deenergized to disable the deceleration energy recovery device (steps 237 and 238).
. Therefore, when the vehicle is in a steady running state, the vehicle is driven only by the driving force of the engine 1 (Fig. 14).
. Further, when the vehicle changes from a steady running state to a state where the accelerator pedal is simply returned to a position where the amount of depression is zero, it is determined in step 212 of FIG. 5 that the amount of depression of the accelerator pedal is zero, and then step 213 is executed. Then, the electromagnetic clutch 14 is disengaged (off). Therefore, even in such a case, the vehicle is driven only by the driving force of the engine 1. However, if the brake pedal is depressed and the vehicle enters a deceleration state, for example, if the brake is depressed from a steady running state (proceeding to step 240 after the determination in step 212 in FIG. If the pump is depressed (step 189 proceeds after the determination in step 185 in FIG. 8), pump tilting control is executed and deceleration energy is accumulated in the accumulator 41 in the following manner. FIG. 11 shows a flowchart of the pump tilting control subroutine. First, in step 241, the ECU 64
The 13th step connects the electromagnetic clutch 14 and outputs a pump tilting angle control signal corresponding to the amount of depression of the brake pedal to the drive circuit 36 based on the signal from the brake sensor 66 shown in FIG. 11 (step 242). The figure is a graph showing an example of the relationship between the pump tilt angle control signal output value output by the ECU 64 and the amount of brake pedal depression. The output value increases linearly, and when the amount of depression reaches a first predetermined value (for example, 30%) of the total amount of depression, the output value reaches a positive predetermined maximum value Vp (for example, a predetermined value between +3V and +5V). It is set. Therefore, if the amount of depression of the brake pedal exceeds the first predetermined value (30%), the pump capacity will increase to the maximum value (30%).
In other words, the pump is set so that the deceleration energy can be stored at the maximum rate in the accumulator 41 at a relatively early stage of depression of the brake pedal.
The rotation angle of the motor 16 is controlled. Next, the ECU 64 detects the vehicle speed based on the vehicle speed signal V from the vehicle speed sensor 73 (step 243), and also detects the vehicle speed based on the signal from the gear position sensor 68. The selected gear is detected (step 244). Then, the ECU 64 calculates the synchronous engine rotation speed NO of the engine clutch 2 from the detected vehicle speed and gear, stores this (step 245), and proceeds to step 246. In step 246, it is determined whether the amount of brake pedal depression is equal to or greater than a second predetermined value (for example, 10% of the total amount of depression).This second predetermined value is slightly less than the amount of play of the brake light. It is set to a small value.When it is determined that the amount of depression of the brake pedal is equal to or higher than the second predetermined value (10%), the ECU 64 turns on the brake lamp (stop lamp).
88 is turned on (step 256), the process proceeds to step 257, and the selected gear stage of the transmission 3 is detected. If the selected gear is neutral, engine clutch 2 is left engaged (step 258), and the process returns to the main routine, and if the selected gear is a gear other than neutral, engine clutch 2 is disengaged. (step 255) and returns to the main routine. This allows the wheels 12c to rotate no matter what position the gear is in. As shown in FIG. 15, the rotation of 12c is caused by the propeller shaft 12a, the main shaft PTO gear 6, and the horse drive gear 7a.
, 7b, PTO output shaft 8, joint 13 and electromagnetic clutch 1
4 to the pump motor 16, which drives the pump motor 16 which operates as a pump. The pressure oil generated by the pump motor 16 is transferred to the first boat 28 and the high pressure oil line 40.
It is stored in the accumulator 41 through the process. At this time, since the power transmission path from the wheels 12C312C to the engine 1 is cut off, substantially all of the deceleration energy is used to drive the pump motor 16. If it is determined that the amount of depression of the brake lamp is equal to or less than the second predetermined value (10%) (step 246), the process proceeds to step 247, where the ECU 64 turns off the brake lamp 88 and then turns off the electronic governor control unit 86. The detected engine speed Ne supplied from the synchronous engine speed NO obtained in step 245 is compared (
Ste.71248). As a result, when the detected engine speed Ne is greater than the synchronous engine speed NO, the process proceeds to step 255, where the engine clutch 2 is disengaged and the process returns to the main routine. In this way, even if the amount of depression of the brake pedal is smaller than the second predetermined value (10%), if the engine speed Ne is larger than the synchronous engine speed No, the power transmission path between the wheels 12c, 12c and the engine 1 is changed. is cut off, and the wheels 12c, ! Almost all of the driving force 2c is transmitted to the pump/motor 16, and the deceleration energy is stored in the accumulator 41 without waste. As a result of the comparison in step 248, if the detected engine speed Ne is equal to or less than the synchronous engine speed NO, the process proceeds to step 249, where it is determined whether or not the engine clutch 2 is disengaged. If the engine clutch 2 is disengaged, the process advances to step 250, and the ECU
64 sends a pseudo accelerator signal to the electronic governor control unit 86 to control the electronic governor control unit 8.
6, the fuel injection pump is operated to increase the amount of fuel supplied to the engine 1, thereby increasing the engine speed (step 251), and the engine speed is again synchronized with the engine speed detection value Ne. Compare with NO (Step 252), engine speed detection value Ne
If Ne is still smaller than the synchronous engine rotational speed NO, steps 250 and 251 are repeated, and the process waits until the engine rotational speed Ne becomes equal to the synchronous engine rotational speed NO. When the detected engine speed Ne becomes equal to or higher than the synchronous engine speed NO, the ECU 64 returns the accelerator signal supplied to the electronic governor control unit 86 to the true value from the accelerator sensor 65 (step 253). , the engine clutch 2 is brought into contact (step 254). In this way, the engine clutch 2 is engaged after the engine speed is increased so that the engine speed Ne matches the synchronous engine speed NO, so the engine clutch 2 can be engaged and operated extremely smoothly and quietly. . In step 249, if the engine clutch 2 is already engaged, the process returns to the main routine without doing anything. In this way, when the amount of depression of the brake pedal is less than the second predetermined value (10%) and the engine speed Ne is equal to or less than the synchronous engine speed NO, the deceleration energy is used to drive the pump motor 16. It will be used for both engine braking. When the amount of oil pumped into 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 and the hydraulic oil is returned to the pressurized oil tank 43 via the relief valve oil path 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. As described above, the fan 53 driven by the hydraulic motor 51 blows air to the cooler 52 to enhance the oil cooling effect of the cooler 52. In the above-described embodiments, the present invention is applied to a diesel engine, but it goes without saying that the present invention may also be applied to a gasoline engine. 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 'AH 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 A transmission having a multi-stage gear train mechanism that changes speed and transmits the rotation of a countershaft to the main shaft, a countershaft PTO gear detachably mounted on the countershaft via a countershaft Pro gear synchronizer, and the countershaft PTO gear. A main shaft PTO gear meshing with the gear and detachably mounted on the main shaft via a main shaft PTO gear synchronizer, and a PTO output driven via a drive gear meshing with the main shaft PTO gear. a stepped-speed PTO output device, a pump motor connected to the PTO output shaft, a high pressure oil circuit extending from a first boat of the pump motor to an accumulator, and a high pressure oil circuit extending from a second boat of the pump motor to an oil tank; Since it is equipped with a low-pressure oil circuit and a one-port control means that allows the pump/motor to function as either a pump or a motor depending on the operating condition of the vehicle, it is possible to recover deceleration energy and use it as starting energy. It does not require any complicated devices or equipment to use, and has a simple structure. It also has the effect of improving fuel efficiency by recovering deceleration energy and using it as starting energy. Also, a pressurized air supply source connected to the oil tank and supplying pressurized air to the oil tank, an on-off valve disposed in an air passage between the pressurized air supply source and the oil tank, and detecting vehicle speed. and a switch means for manually turning on and off electric power supplied to at least the multi-speed PTO output device and the on-off valve via the control means, the control means controlling the vehicle speed. When the vehicle speed detected by the sensor is substantially zero and the switch means is turned on, the opening/closing valve is opened, thereby preventing cavitation in the low pressure oil circuit when the pump/motor deceleration energy recovery operation is activated. In addition, since there are no restrictions on the installation location of the oil tank, space can be used effectively.Furthermore, pressurized air is supplied to the oil tank only when the deceleration energy recovery device is operating, so the deceleration energy recovery device can be used when the engine is stopped, etc. This provides various effects such as minimizing the amount of hydraulic oil leaking from the seal portion of the hydraulic circuit from the oil tank to the accumulator during non-operation, and reducing the drain tank capacity.

[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 vertical side view of the pump and motor shown in Fig. 1, and Fig. 3 is a diagram of the same pump and motor. FIG. 4 is a longitudinal sectional front view of the capacity control solenoid valve of FIG. 3, and FIG. 5 is a longitudinal sectional side view of the capacity control solenoid valve of FIG. A main flowchart showing the control procedure, FIG. 6 is a flowchart of the solenoid valve A-B control subroutine executed at step 110 of the main flowchart of FIG. 5, and FIG. 7 is a flowchart of step 1 of the main flowchart of FIG. 5.
8 is a flowchart of the start control subroutine executed at step 170 of the main flowchart of FIG. 5, and FIG. 9 is a flowchart of the main flowchart of FIG. A flowchart of the motor tilting control subroutine executed, FIG. 10 is a flowchart of the speed change control subroutine executed at step 190 etc. of the main flowchart of FIG. 5, and FIG. 11 is a flowchart of step 240 etc. of the main flowchart of FIG. 5. Flowchart of pump tilting control subroutine executed in 12th
The figure shows an example of the relationship between the output value of the motor tilt angle control signal output from the electronic control unit to the drive circuit of the solenoid valve for capacity control and the accelerator pedal depression M (accelerator opening degree) when the morph tilt control is executed. Figure 13 shows an example of the relationship between the output value of the pump tilting angle control signal output from the electronic control unit to the drive circuit of the capacity control solenoid valve during execution of pump tilting control and the amount of depression of the brake pedal. The graph, Fig. 14 is an operation explanatory diagram of the deceleration energy recovery device showing the transmission path of the driving force transmitted from the engine to the wheels during steady running of the vehicle, and Fig. 15 shows the transmission path of the driving force transmitted from the wheels to the pump/motor when the vehicle is decelerating. An explanatory diagram of the operation of the deceleration energy recovery device showing the transmission path of the driving force, Part 1
Figure 6 is an explanatory diagram of the operation of the deceleration energy recovery device showing the transmission path of the driving force transmitted from the engine to the pump motor when the vehicle is stopped, and Figure 17 is the driving force transmitted from the pump motor to the wheels when the vehicle is started. FIG. 18 is an explanatory diagram of the operation of the deceleration energy recovery device showing the transmission path of the deceleration energy recovery device, and FIG. . ■...Engine, 2...Clutch, 3...Transmission, 3''...Multi-speed PTO output device,
4... Main shaft, 5... Counter shaft,
6... Main shaft PTO gear, 7a, 7b...
Horse section moving gear, 8... PTO output shaft, 9... Main shaft PTO gear synchronizer, 10... Counter shaft PTO gear, 11... Counter shaft PT
O gear synchronizer, 16... pump motor, 1
7゜18...Multi-stage gear train mechanism, 30...Solenoid valve for capacity control, 32...Piston, 40...High pressure oil path,
41...Accumulator, 42...Low pressure oil circuit, 4
3... Pressurized tank, 45... Air tank, 46...
- Solenoid valve, 54... Supply oil path, 59... Oil pump, 64... Electronic control unit, 65...
Accelerator sensor, 66... Brake sensor, 73...
・Vehicle speed sensor, 78... Main switch, 83...
Electronic governor, 84... Fuel injection pump, 86... Electronic governor control unit, 90... Rotational speed sensor.

Claims (1)

[Claims] A transmission having a countershaft driven via a clutch on the engine side, a main shaft connected to a wheel drive system, and a multi-stage gear train mechanism that changes speed and transmits rotation of the countershaft to the main shaft;
A countershaft PTO gear is detachably mounted on the countershaft via a countershaft PTO gear synchronizer, and the countershaft PTO gear meshes with the countershaft PTO gear and is detachably mounted on the main shaft via a mainshaft PTO gear synchronizer. a multi-speed PTO output device having a main shaft 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 extending from a first port of the pump/motor to an accumulator; a low pressure oil circuit extending from a second port of the pump/motor to an oil tank; connected to the oil tank to supply pressurized air to the oil tank; a pressurized air supply source for controlling the air pressure, an on-off valve disposed in the air passage between the pressurized air supply source and the oil tank, a vehicle speed sensor for detecting vehicle speed, and a pump/motor for controlling the pump and motor depending on the operating state of the vehicle. A control means for functioning as either one of the motors, and a switch means for manually turning on and off electric power supplied to at least the multi-speed PTO output device and the on-off valve via the control means, The control means opens the on-off valve when the vehicle speed detected by the vehicle speed sensor is substantially zero and the switch means is in an on state. Device.