JPH03244873A - Differential pressure sensor and automatic transmission - Google Patents

Abstract

PURPOSE:To improve the extent of control accuracy by conducting the measured differential pressure into a high pressure chamber and a low pressure chamber of a cylinder partitioned off by a piston, and having a beam or piston rod stuck with a strain gauge elastically deformed by movements of the piston. CONSTITUTION:In a differential pressure sensor 10 available for a hydraulic circuit or the like of an automatic gear for vehicle use, the inside of a bore 12 of a cylinder body 11 is partitioned into a high pressure chamber 14 and a low pressure chamber 15 by means of a piston 13, and a ball end 24 at the tip of an elastic beam 16, whose base end is locked, is engaged with a ring groove 23 of the piston 13, then each strain gauge 17 is stuck to both the sides. When high pressure side hydraulic pressure of the hydraulic circuit is guided into the high pressure chamber 14 and low pressure side hydraulic pressure into the low pressure chamber 15, respectively, the piston 13 is moved by the differential pressure, having the elastic beam 16 elastically deformed, and a signal conformed to the differential pressure is taken out of the strain gauge 17 via a lead 25, then it is fed back to a hydraulic controller. Thus improvement in control accuracy is well promotable.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a differential pressure sensor used in hydraulic circuits such as power steering and hydraulic clutches, and
The force used to press the clutch disc is controlled directly by hydraulic pressure using a mechanical friction clutch and a shift clutch.
Electro-hydraulic automation in combination with a countershaft transmission in which the cylinder and select cylinder are hydraulically driven to change the gear mesh, with the hydraulic circuit influencing temperature-induced backpressure changes. The present invention relates to automatic transmissions in which the hydraulic circuits which control them without being controlled are hydraulic feed hacks.

BACKGROUND ART Today, pneumatically controlled automatic transmissions are widely used in route bus systems.

The automatic transmission uses a coil spring oil spray clutch for clutch control, pneumatic spring chamber means, and a constant mesh counter for the transmission. A shaft-type transmission is used, and the transmission is controlled by pushing and pulling the shift and select shaft with an air select cylinder to select, and then applying torsion with the air shift cylinder to shift. has been done.

The fuel efficiency of large route HAS equipped with this automatic transmission is the same or slightly better than that equipped with a normal manual transmission, and although the smoothness is excellent and good, the torque during shifting is There was room for improvement in agility during interruptions.

Therefore, in recent years, automatic transmission devices that electro-hydraulicly automate the combination of a mechanical friction clutch and a mechanical transmission have been provided. Since a pressure sensor is used, the back pressure of the pressure sensor is affected by temperature, and errors occur in the control of the hydraulic circuit.

OBJECTIVES AND PROBLEMS OF THE INVENTION An object and problem of the present invention is to make it possible to sense the oil pressure in a hydraulic circuit without being affected by temperature, to avoid errors in controlling the hydraulic circuit, and to provide power steering, The present invention provides a differential pressure sensor suitable for hydraulic circuits such as hydraulic clutches, transmissions, and automatic transmissions.

Other objects and problems of the present invention are to shorten the shift time, make the shift quick, enable the combination of a mechanical friction clutch and a mechanical transmission, and reduce back pressure changes due to temperature. In other words, it is possible to control the hydraulic circuits without being affected, in other words, to avoid errors in the control of the hydraulic circuits, thereby improving efficiency, fuel consumption, and
The object of the present invention is to provide an automatic transmission that improves economic efficiency and is suitable for commercial vehicles.

Still another object and problem of the present invention is to automate the combination of a mechanical friction clutch and a mechanical transmission by electro-hydraulic control,
In addition, it is possible to control the hydraulic circuit without being affected by changes in back pressure caused by temperature. In other words, it is possible to avoid errors in the control of the hydraulic circuit, and to improve drivability. The purpose of the present invention is to provide an automatic transmission device that improves performance such as vehicle speed and power performance, and is suitable for commercial vehicles.

Still other objects and problems of this invention are the above-mentioned objects and problems.
Another object of the present invention is to provide an automatic transmission that reduces the clutch stroke and makes starting and shifting smoother.

Still another object and problem of the present invention, in addition to the above-mentioned object and problem, is to provide an automatic transmission that enables smooth transmission of power.

Summary of the invention related to objects and problems: Contents of the claimed invention In relation to the above-mentioned first object and problem, the differential pressure sensor of the present invention is characterized in that high pressure and low pressure are measured by a piston and a cylinder body. The beam or the piston rod is guided into a high pressure side cylinder chamber and a low pressure side cylinder chamber divided in the bore, and is deformed by the piston.
Then, the strain gauge connects the beam or 1.
It is constructed where the piston rod is distorted,
The purpose is to make it possible to sense the oil pressure in hydraulic circuits such as power steering, hydraulic clutches, transmissions, and automatic transmissions without being affected by temperature, thereby avoiding control errors in these hydraulic circuits.

Further, in relation to the other objects and problems mentioned above, the automatic transmission device of the present invention includes a high pressure side cylinder chamber and a low pressure side cylinder chamber that are partitioned into the cylinder by a piston, and
An oil spray type hydraulic clutch with a hydraulic clutch control cylinder located on the flywheel to move the pressure plate and a shift clutch.
A mechanical transmission having a cylinder, a shift valve, a select cylinder, and a select valve, and a high-pressure side and low-pressure side clutch connected correspondingly to the high-pressure side and low-pressure side cylinder chambers of the hydraulic clutch control cylinder. control hydraulic piping,
A system having transmission control hydraulic piping connected to the shift cylinder and select cylinder via the shift valve and select valve, and a flow control valve that controls the flow rate of pressurized oil discharged from the hydraulic pump.・Clutch oil with a control hydraulic circuit and an oil spray control valve that controls the flow rate of oil sprayed onto the clutch disc of the hydraulic clutch.
a spray circuit, a clutch transmission select valve disposed in its high pressure side clutch control hydraulic line, and a pressure control valve disposed in its low pressure side clutch control hydraulic line and having a pressure control pilot valve; High pressure and low pressure measurement pressures are guided from the high pressure side and low pressure side clutch control hydraulic piping to high pressure side cylinder chambers and low pressure side cylinder chambers defined in the cylinder bore of the cylinder body by pistons, and the beam or , the piston rod is
It is deformed by the piston, and the strain gauge is
A differential pressure sensor that detects clutch differential pressure by being distorted by the beam or piston rod, and in addition to that differential pressure sensor, a select lever position sensor, an accelerator position sensor, and an engine speed sensor , brake oil pressure sensor, gear position sensor,
Then, the signal from the vehicle speed sensor is input and the shift
a control unit that controls a valve, a select valve, and a pressure control pilot valve, the differential pressure sensor sensing oil pressure in the system control hydraulic circuit; In response to the oil pressure sensed in the system, the pressure control pilot valve is actuated to control the oil pressure in the system control hydraulic circuit without being affected by changes in backpressure due to temperature. and as such, that single pressure control valve controls the system
As a result of regulating the pressure oil in a control hydraulic circuit, errors in the control of that hydraulic circuit due to changes in backpressure due to its temperature are avoided, and in that way the single pressure control valve The oil spray control valve adjusts the oil pressure of the system control hydraulic circuit to shorten the shifting time and make the shifting agile, and the oil spray control valve adjusts the hydraulic clutch according to the state of the hydraulic clutch. - The automatic transmission device of the present invention has the above-mentioned configuration by adjusting the flow rate of oil sprayed onto the disc and connecting the hydraulic clutch while sliding it, thereby greatly reducing the actual shift time. In addition,
It is equipped with a trigger spring that is placed in the low-pressure side cylinder chamber and steps amplifies the hydraulic pressure acting on the piston in the high-pressure side cylinder chamber just before the clutch is engaged, and detects clutch engagement using hydraulic pressure. Further, the automatic transmission of the present invention has the above-mentioned configuration, and further includes a cylinder and a piston of the hydraulic clutch control cylinder. A throttle passage is formed in either one of the cylinder chambers on the high-pressure side to the cylinder chamber on the low-pressure side to generate a slight flow of pressure oil, and the air bubbles mixed in the pressure oil are discharged from the hydraulic circuit. Furthermore, the automatic transmission of the present invention has the above-described structure, and furthermore, the flywheel of the hydraulic clutch is fixedly connected to the crankshaft of the engine. The automatic transmission device of the present invention has a flex plate connected to the flex plate to smooth the transmission of power.
Furthermore, a check valve is installed in the high-pressure side clutch control hydraulic piping upstream of the clutch transmission select valve, and a check valve is installed in the low-pressure clutch control hydraulic line downstream of the pressure control valve.
A back pressure valve is provided in a branch pipe branching from a control hydraulic pipe to suppress hydraulic fluctuations in the clutch control hydraulic circuit and to smoothly engage and engage the clutch. The automatic transmission has the above-mentioned configuration, and further includes a stop valve disposed in the high pressure side clutch control hydraulic piping downstream of the clutch transmission select valve, and the high pressure side clutch control hydraulic line. a short circuit valve located at a point in the hydraulic piping connecting the downstream side of the stop valve to the downstream side of the pressure control valve in the low pressure side clutch control hydraulic piping, and the stop valve and the short circuit;・Short-and-stop control that controls the pressure oil that operates the valve.
valve, and when the hydraulic clutch disconnects the transmitted torque, the clutch transmission select valve is connected to the pressure control valve and the short and
The stop control valve is operated by the hydraulic pressure applied by the stop control valve and stops the flow of pressure oil from the hydraulic pump to the clutch control hydraulic circuit.
Close the valve and open the short circuit valve to short-circuit the high and low pressure sides of the clutch control hydraulic circuit to momentarily disengage the hydraulic clutch, further shorten shift time, and It's about improving agility.

Furthermore, to simply describe the automatic transmission device of the present invention explained in relation to the above-mentioned objects and problems, the starting point of the automatic transmission device of the present invention is a mechanical friction clutch and a counter shirt model 1 to 1. The combination of mechanical transmission and the most mechanically efficient comrades is automated through electronic control. The countershaft type mechanical transmission has fewer meshing parts and bearings than planetary types (and there is no clutch part that can cause drag, so
Friction loss is low, and there is no need to explain the high efficiency of the mechanical friction clutch.

Therefore, there is no system that is superior to this in terms of economy, but the reliability of the system is improved by minimizing the errors when controlling the system.
In addition, when shifting, it is necessary to disengage one gear and then engage another gear, so there is a problem in that it takes time to shift, and how this time can be shortened is the key to the drivability of this system. It is the basis for improving performance such as power and power performance.

Also, the need for quick gear changes is greater for trucks than for buses.
Medium-duty trucks are more expensive than heavy-duty trucks.

Therefore, in order to reduce this error, various viewpoints and measures can be considered, but one is to perform electro-hydraulic control of the system and accurately detect the oil pressure.

In addition, various viewpoints and measures can be considered in order to shorten the gear shift time, but the first is to quickly change the engine rotation to a rotation that matches the next gear step, and the second is , at least sooner than the necessary engine speed changes are made (clutch disengagement, gear removal, select,
The goal is to complete each step of shifting and clutch engagement.

In order to satisfy the first point of view, it is necessary to improve the response of the engine itself, especially the response of down-revs, reduce the rotational inertia of the clutch and chi, and reduce the width of the gear step to reduce the change in engine speed. It is possible to reduce the required width. In order to satisfy the second viewpoint, for the clutch, it is necessary to increase the stroke speed and reduce the stroke, and for the transmission, it is necessary to remove the gear, select the gear,
It is conceivable to adopt a gear shift structure that improves the speed of gearing and allows gears to be pulled out and put into gear at the same time.

The automatic transmission of the present invention addresses the first point of view by reducing the diameter of the clutch and reducing the rotational inertia.
This is compensated for by replacing the typical coil spring type with a hydraulic type and increasing the load that presses the clutch disc. By adopting a hydraulic method, it is possible to cut off the transmitted torque with a slight latch stroke, and by adopting a hydraulic type for the shift cylinder and select cylinder, it is easy to control the shift load. As a result, the shift time is shortened, and by taking such measures, the automatic transmission of the present invention can satisfy the second viewpoint at the same time.

Description of Specific Examples Specified specific examples of the differential pressure sensor and automatic transmission of the present invention will be described below with reference to the drawings.

FIG. 1 shows a tenth specific example of the differential pressure sensor of the present invention.

The differential pressure sensor 10 includes a cylinder body 11 having a cylinder bore 12 therein, and a cylinder body 11 having a cylinder bore 12 therein.
a piston 13 that is slidably fitted into the cylinder bore 12 and defines a high-pressure side cylinder chamber 14 and a low-pressure side cylinder chamber 15; an elastic beam 16 connected to the piston 13; It was fabricated including strain gauges 17, 17 bonded to the beam 16.

The cylinder body 11 has a high pressure side cylinder chamber 1.
A pump boat 18 and an upstream pressure boat 20 are opened in the cylinder bore 12 corresponding to 4, and the cylinder bore 12 is corresponding to the low pressure side cylinder chamber 15.
Tank boat 19 and downstream pressure boat 2 opened to
1 and a window 22 opened at an intermediate position in the length direction of the cylinder bore 12.

The piston 13 has a ring groove 23 formed on its outer peripheral surface at an intermediate position in the length direction.

The elastic beam 16 is manufactured in the form of a cantilever beam with a ball end 24 at its tip, and its base is screwed to a bracket (not shown) protruding from the outer peripheral surface of the cylinder body 11. is extended into the cylinder bore 12 through a window in the cylinder body 11, and its ball end is fitted into the ring groove 23 of the piston 13, so that the ball end is elastically deformed by the movement of the piston 13. They were assembled to the cylinder body 11 and piston 13 so as to

The strain gauges 17, 17 are, as illustrated,
It was fabricated in the usual manner to be glued to the elastic beam 16 and connected by leads 25, 25 to a power supply circuit (not shown) and an amplifier circuit (not shown).

As mentioned above, this differential pressure sensor 10 has its upstream pressure boat 20 and downstream pressure boat 21 communicated with the high pressure side and low pressure side cylinder chambers 14, 15, so that the differential pressure sensor 10 is connected to the equipment in the hydraulic circuit. can be easily connected to. In that case, the upstream pressure boat 20 is connected to the upstream side of the device in the hydraulic circuit, and the downstream pressure boat 21 is connected to the downstream side of the device.

Moreover, the differential pressure sensor 10 manufactured with such a structure
This makes it possible to sense the differential pressure of the pressure oil flowing in the hydraulic circuit, and avoids errors that occur in the control of the hydraulic circuit due to changes in back pressure caused by temperature.

FIG. 2 shows another specific example 30 of the differential pressure sensor of the present invention.

This differential pressure sensor 30 includes a cylinder body 31 having a cylinder bore 32 therein, and a cylinder body 31 having a cylinder bore 32 therein.
a piston 33 that is slidably fitted into the cylinder bore 32 and defines a high pressure side cylinder chamber 34 and a low pressure side cylinder chamber 35; a piston rod 34 fixed to the piston 33; A strain gauge 1717 was bonded to the piston rod 34.

The cylinder body 31 has a high pressure side cylinder chamber 3.
4, and a pump boat 36 and an upstream pressure boat 38 opened to the cylinder bore 32 thereof corresponding to the cylinder chamber 35 on the low pressure side thereof, and a cylinder bore 32 corresponding to the low pressure side cylinder chamber 35 thereof.
Tank boat 37 and downstream pressure boat 3 opened to
9 and a pair of rod through holes 40, 41 opened in the cylinder bore 32 thereof.

The piston rod 34 is inserted into the rod through hole 40.
41 and fixed to the piston 33 in the form of both rods.

Further, this piston rod 34 has one end extended to the outside of its cylinder body 31, and the extended portion is cut out to form a thin elastic portion 42 in the extended portion.
, and the axial end of the elongated portion is formed into a clamp end 43. Of course, the clamp
The end 43 is screwed to a bracket 44 protruding from one end face of the cylinder body 31, and the extendable portion 42 is made to be elastically expanded and contracted by the movement of the piston 33.

The strain gauges 17, 17 are, as illustrated,
The lead wire 2 is bonded to the stretchable portion 42 and
5. At 25, the power supply circuit (not shown) and the amplifier circuit (
(not shown).

This differential pressure sensor 30 described above is constructed in the same way as the differential pressure sensor IO described above. Used in hydraulic circuits.

3 to 9 show a specific example 50 of the automatic transmission of the present invention applied to a medium-sized truck, and the above-mentioned differential pressure sensor IO was used in this automatic transmission 50.

The automatic transmission 50 includes an oil spray type hydraulic clutch 51, a shift cylinder 53 and a select cylinder 5 that operate a gear shift and select shaft (gear shift and select lever).
4 and its corresponding shift solenoid valves 55,56 and select solenoid valves 57,58,59 for directional control of the flow of pressure oil to the select cylinders 54
A system control hydraulic circuit including a shaft-type transmission 52, a high-pressure side clutch control hydraulic line 61, a low-pressure side clutch control hydraulic line 62, and a transmission control hydraulic line 63, and further includes a flow control valve 64. 60, a clutch oil spray circuit 65 with an oil spray control valve 66, a clutch transmission select hull blower, a pressure control valve 68 with a pressure control pilot valve 69, and the system. Control hydraulic circuit 60
A short circuit valve 70, a back pressure valve 71, a stop valve 72, and a short circuit valve 73 are arranged in・Stop control valve 74, electronic control unit 7
5, a select lever position sensor, an accelerator position sensor, an engine speed sensor, a brake oil pressure sensor, and the oil pressure connected to the high pressure side and low pressure side clutch control oil pressure piping 61, 62. In the clutch 51, the high pressure side (D) and the low pressure side (
C) includes a differential pressure sensor (clutch differential pressure sensor) 10, a gear position sensor, and a vehicle speed sensor, and its electronic control unit 75 is affected by changes in oil temperature. Without further ado, the pressure control pilot HALPRO 9 is operated according to the differential pressure between the high pressure side (D) and the low pressure side (C) of the hydraulic clutch 51 sensed by the differential pressure sensor 10, and The pressure control valve 68 is operated by the pressure control pilot HALPRO 9 to adjust the oil pressure of the hydraulic circuit 60,
The oil spray control valve 66 enables the oil spray control valve 66 to spray oil onto the clutch disc 85 depending on the state of the hydraulic clutch 51. It was manufactured to adjust the flow rate of oil.

In this mechanical automatic transmission 50, the electronic control unit 75 is
As can be understood from the figure, the input circuit is connected to the select lever position sensor, accelerator position sensor, engine speed sensor, brake oil pressure sensor, clutch differential pressure sensor 10, gear position sensor, and vehicle speed sensor. etc., and also connect the output circuit to its shift solenoid valves 55, 56, select solenoid valves 57, 58, 59, pressure control pilot valve 69, and short-and-stop control valves. It is electrically connected to the solenoid coil of valve 74, and when the select lever is operated,
Depending on the signals from those sensors, these solenoids
The short-and-stop control valve 74, the pressure control valve 68, the shift solenoid valve 55, 56, and the select solenoid control the current flowing through the coil and correspond to the position of the select lever. - Valves 57, 58, 59 are operated to cause the hydraulic clutch 51 to engage and disengage, and to cause the transmission 52 to shift based on a preset shift map related to the characteristics of the engine. let it happen. Of course, the electronic control unit 75 is communicatively electrically connected to the electronic control unit controlling the engine 120 and controls the engagement and disengagement of the clutch 51 as adapted to the operating conditions of the engine 120. This allows the transmission 52 to change speed.

As can be seen from FIGS. 5 and 6, the hydraulic crank 51 is connected to a flywheel housing 80 bolted to the rear surface of the cylinder block of the engine 120 and a gear shaft of the transmission 52. On the front surface of the casing, a clutch housing 81 bolted to the flywheel housing 80, and an input shirt of the transmission 52 in a space surrounded by the flywheel housing 80 and the clutch housing 81. l-1
01 rotatably fitted in a sealed state, and an input shaft cover 83.
rotatably fitted around the fly
Clutch cover 84 bolted to wheel 82
, a clutch disc 85 splined to the input shaft 101 , a pressure plate 86 , and a hydraulic clutch control plate 85 between the flywheel 82 and clutch cover 84 .
It is fabricated in a structure that includes a cylinder 87 and a flex plate 88 that fixes its flywheel 82 to the crankshaft 121 of its engine 120, and its lower part is used for an oil pan 89 and its input shaft. An oil spray jet hole 99 is formed in the cover 83 so that oil can be sprayed onto the clutch disc 85 from the oil spray jet hole 99.

In addition, this hydraulic clutch 51 has hydraulic pumps 76 and 77 bolted to the inner surface of the clutch housing 81, and the pump and gear 91 are engaged with a drive gear 90 bolted to the clutch cover 84. The structure is such that the oil in the oil pan 89 is pressurized and the pressurized oil can flow to the system control circuit 60 and clutch oil spray circuit 65.

The hydraulic clutch control cylinder 87 is incorporated into the flywheel 82 and holds the pressure plate 86 .
6 onto the facing of the clutch disc 85, sandwiching the clutch disc 85 between the clutch cover 84 and the pressure plate 86, and separating the pressure plate 86 from the clutch disc 85. Performs intermittent operation.

The hydraulic clutch control cylinder 87 has a ring cylinder 92 formed in the flywheel 82 and a high pressure side that is reciprocally slidably fitted within the ring cylinder 92. It is embodied in a structure including a ring piston (clutch piston) 95 that partitions a cylinder chamber 93 and a low pressure side cylinder chamber 94, and a plurality of trigger springs 96 arranged in the low pressure side cylinder chamber 94, and further , the ring piston 95 has a high pressure side cylinder chamber 93.
A plurality of communication passages 97 are formed to communicate with the low pressure side cylinder chamber 94, and each of the communication passages 97 has a throttle 9.
8 so that the pressure oil always flows slightly from the high pressure side cylinder chamber 93 to the low pressure side cylinder chamber 94, and air bubbles mixed in the pressure oil are discharged from the hydraulic circuit 60. ing. Of course, the communication passage 97 may also be formed as a side passage in the ring cylinder 92, ie the flywheel 82, and if the communication passage 97 is embodied in a narrow passage, the narrow passage The passageway can omit its restriction 98.

As mentioned above, in the hydraulic clutch 51, the ring piston (clutch piston) 95, the pressure plate 86, and the clutch disc 85 are housed within the clutch cover 84, and they are As shown in FIG. 5, it is driven by its engine 120 through a flex plate 88 fixed to the end of its crankshaft 111.

The driving torque is transmitted by the clutch piston 95 to the pressure plate 86 and the clutch cover 84.
By sandwiching the clutch disc 85 between the two, the transmission is transmitted to the transmission 52 side.

A trigger spring 96 is arranged on the clutch piston 95. This trigger spring 96 has the effect of step-amplifying the hydraulic pressure by one step just before the hydraulic clutch 51 is fully engaged. In the cylinder chamber 93, the hydraulic pressure acting on the clutch piston 95 is amplified stepwise, and the hydraulic pressure changes (trigger hydraulic pressure).
is sensed by the clutch differential pressure sensor 10 disposed on the high-pressure side and low-pressure side clutch control hydraulic piping 61, and provided to the electronic control unit 75. This is one of the factors that makes it possible to start and change gears without the need for a clutch stroke.

The transmission 52 is of the fully synchronized countershaft type.

The gear shift unit has its shift cylinder 53
, select cylinder 54, shift solenoid valve 55, 56, and select solenoid valve 57.
, 58 and 59, and is disposed on the gear shift housing mounted above the gear case of the transmission 52. In particular, it is necessary to keep the height of the gear shift housing lower than the frame and to make it compact. from,
A criss-crossing shift rod and select rod method is adopted, and the structure is such that the hydraulic shift cylinder 53 and the hydraulic select cylinder 54, which are small in diameter, are used to directly push and pull. By reducing the cylinder diameter in this way, it is possible to fill the cylinder with oil in a short time, and it also increases the degree of freedom in hydraulic waveform control, maximizing the ability of the synchronizing mechanism and improving the speed of shifting and synchronizing mechanism. This makes it possible to achieve both high levels of durability and durability.

The system control hydraulic circuit 60 includes its high pressure side and low pressure side clutch control hydraulic piping 61.
62, its transmission control hydraulic piping 63, a hydraulic pump 76, and its flow control valve 64 for controlling the flow rate of pressurized oil discharged from the hydraulic pump 76.

The high pressure side clutch control hydraulic piping 61 is connected to the discharge side of the hydraulic pump 76 and the high pressure side cylinder chamber 93 of the clutch control cylinder 87, and the clutch transmission select valve 67 is connected to the upstream side. In addition, its clutch
The check valve 70 is disposed upstream of the transmission select valve 67, and the clutch transmission select valve 67
The stop valve 72 is disposed downstream of the valve.

The low pressure side clutch control hydraulic piping 62 is connected to the discharge side of the hydraulic pump 76 and the low pressure side cylinder chamber 94 of the clutch control cylinder 87, and the pressure control valve 68 is disposed on the upstream side. ,
Further, the downstream side of the pressure control valve 68 is branched, and the hack pressure valve 71 is arranged in the branched line 102.

Further, the high pressure side and low pressure side clutch control hydraulic piping 61, 62 connect the downstream sides of the stop valve 72 and the pressure control valve 68 to each other, and connect the short circuit valve 73 to the connected point. It is placed.

Further, the high pressure side and low pressure side clutch control hydraulic lines 61,62 are connected between the clutch transmission select valve 67 and the stop valve 72 and between the pressure control valve 68 and the short valve.
The differential pressure sensor 10 is connected between the circuit valve 73 and the circuit valve 73. Of course, the differential pressure sensor 10 has its pump port 18 facing its clutch transmission select valve 67 side, and its upstream pressure port 20 facing its stop valve 72 side, so as to control the high pressure side clutch control hydraulic pressure. The tank boat 19 is connected to the piping 61, and the tank boat 19 is connected to the pressure control valve 68 side, and the downstream pressure boat 21 is connected to the short circuit.
They are connected to the low pressure side clutch control hydraulic piping 62 facing toward the valve 73 side.

The transmission control hydraulic line 63 connects the discharge side of the hydraulic pump 76 to the shift cylinder 5 via the shift solenoid valve 55, 56.
3, and the discharge side of the hydraulic pump 76 is connected to the select cylinder 54 via its select solenoid valves 57, 58, 59.

The flow control valve 64 is connected to the aperture 103
The pump is placed on the upstream side of the pump and is driven by hydraulic pressure led from the downstream side of the throttle 103 through the pressure lead piping 104.
Excess pressure oil is returned to the suction side of the hydraulic pump 76 by the bypass 105, and the flow rate of the pressure oil flowing into the hydraulic pipes 61, 62, 63 is adjusted to a constant level, and the flow rate from the hydraulic pump 76 is adjusted according to the rotation speed of the engine 120. Pressure fluctuations in the hydraulic piping 61, 62, 63 due to fluctuations in the flow rate of the pressure oil to be sent are suppressed.

The clutch transmission select valve 67 is operated by the hydraulic pressure downstream of the throttle 103 switched by the short-and-stop control valve 74 and the hydraulic pressure downstream of the pressure control valve 68, The transmission 52 uses its shift cylinder 53 and select cylinder 54 to select gears.
When the transmission is changed, the hydraulic clutch 51 is in a state where the transmission torque is cut off, so the pressure oil flowing to the high pressure side clutch control hydraulic piping 61 is stopped and the pressure oil is allowed to flow to the transmission control hydraulic piping 63.

In other words, this clutch transmission select valve 67 is operated by two hydraulic pumps 76,
This enables the hydraulic clutch 51 to be engaged and engaged and the transmission 52 to change gears.

The stop valve 72 and the short circuit valve 73 control the aperture 10 which is switched by the short and stop control valve 74.
When the hydraulic clutch 51 cuts off the transmitted torque, the stop valve 2 is closed and the short circuit valve 7
3 is opened, and accordingly, its high-pressure side and low-pressure side clutch control hydraulic pipes 61, 62 are short-circuited to each other, momentarily disengaging the hydraulic clutch 51.

Of course, the short-and-stop control valve 74 was configured as a solenoid valve whose spool was driven by a solenoid coil.

The clutch oil spray circuit 65 is a circuit that adjusts the flow rate of pressure oil discharged from the hydraulic pump 77 and sprayed onto the clutch disc 85 of the hydraulic clutch 51 using the oil spray control hydraulic piping 66. an oil cooler 106;
An oil spray release valve 107 and an oil spray pressure valve 108 are included.

The oil spray control valve 66 is
A pressure lead pipe 109 is connected to the high pressure side clutch control hydraulic line 61 on the downstream side of the clutch transmission select valve 67, and guides the pilot hydraulic pressure from the high pressure side clutch control hydraulic line 61.

Also, this oil spray control valve 6
6 is a structure that enables the use of the auxiliary oil spray piping 110 to reduce the oil spray flow rate when the respective hydraulic clutch 51 is disengaged. That is,
The oil spray control valve 66 is
The hydraulic clutch 51 is operated by the pilot hydraulic pressure.
increases or decreases the oil spray flow rate depending on the disconnected, partially engaged, and engaged conditions.

More specifically, the hydraulic circuit of automatic transmission 50 is comprised of two parts: its system control hydraulic circuit 60 and its oil spray control circuit 65.

Hydraulic pumps 76 and 77 of the volume circuits 60 and 65
is driven by a drive gear 90 attached to its clutch cover 84, and always spits out oil when its engine 120 is running. Furthermore, the flow control HALPRO 4 always keeps the flow rate of the pressure oil in the system control hydraulic circuit 60 constant so that the control of the pressure control valve 68 is not disturbed due to fluctuations in engine rotation.

The oil spray flow rate is also controlled by the oil spray control valve 66 such that the flow rate is increased when the clutch is partially engaged, and the flow rate is decreased when the clutch is fully engaged and disengaged. .

In this system control hydraulic circuit 60,
Normally, the shift valves 55, 56, select valves 57, 58, 59 and short circuit valve 73 are closed, whereas the pressure control valve 68, clutch transmission select valve 67,
and stop valve 72 is open.

In this state, the pressure oil is in its hydraulic circuit 60 shown in FIG.
, (E), (F) flow in this order, and the symbols (A), (
In B) and (C), the check valve 7O
-(Y) and back pressure valve 7l-(Z
), the pressure is slightly increased.

This minute oil pressure is generated in (C) of the hydraulic circuit 60.
The clutch piston 95 is pushed to disengage the hydraulic clutch 51.

The hydraulic pressure in (A) of the hydraulic circuit 60 is regulated by the pressure control valve 68, and the Byrond pressure is applied to the clutch/transmission select valve (G) of the clutch/transmission select valve 67. Open 67. Therefore, the pressure oil reaches (D) via (E) and connects the hydraulic clutch 51 there. Hydraulic pressure proportional to the transmission torque of the hydraulic clutch 51 (
E) uses its electronic differential pressure sensor 10.
Feedback is provided to control unit 75.

Also, the short-and-stop control valve 74 is moved to the right in FIG. 4, opening the short-circuit valve 73, and
When the stop valve 72 is closed, (C) and (D)
The hydraulic pressure becomes the same as that of the hydraulic clutch 51, and the transmitted torque can be cut off without stroking the hydraulic clutch 51.

In this state, the valves 55, 56, 57, 58, and 59 are opened and closed in the combination shown in FIG. 4, and gears can be shifted and selected.

When shifting the gear, the hydraulic pressure in (A) of the hydraulic circuit 60, which is proportional to the shifting force, is controlled by the pressure control valve 68.

By the way, the oil pressure in (E) of the hydraulic circuit 60 is
It acts as a pilot oil pressure for the oil spray control valve 66, and when the clutch oil pressure is low,
That is, when the hydraulic clutch 11 is disengaged, the oil spray control valve 66 reduces the oil spray flow rate to reduce clutch drag, and when the oil pressure is rising, the oil spray control valve 66 reduces oil spray flow to reduce clutch drag. That is, when the hydraulic clutch 51 is slipping, it prevents clutch facing friction and increases the oil spray flow rate for smooth slipping.

Next, the operation of the automatic transmission 50 described above will be explained. In this operation, the electronic control unit 75 controls the high pressure side ( D
) and the low pressure side (C), the pressure control pilot valve 69 is operated, and the pressure control pilot valve 69 controls the valve opening/closing operation and opening degree of the pressure control valve 68. The pressure control valve 68 adjusts the oil pressure of the hydraulic circuit 60 without being affected by changes in back pressure caused by temperature, so-called oil temperature, which occurs in the control of the hydraulic circuit 60, i.e., its It plays an important role in operating the hydraulic clutch 51 and transmission 52 by avoiding errors that occur in controlling the operations of the hydraulic clutch 5I and transmission 52. When controlling the pressure control valve 68, the current, oil pressure, and output rotation speed of the transmission 52 are fed back to the control unit 75. The control unit 75 also changes the control parameters depending on the oil temperature and the operating state of the device to actively control the device.

First, regarding the start control, as shown in FIG. 7, which shows the change in oil pressure when the clutch is engaged, there is a stepwise change in oil pressure at the starting point of a half-clutch, and this is the trigger oil pressure described above. In order to start quickly, the clutch oil pressure is usually kept at this trigger oil pressure, and the clutch starts to engage immediately when starting.

Regarding gear shift control, for quick control, clutch control during gear shifting cuts off only the transmitted torque with a small stroke, and shifts the shift load load to the synchronized mechanism's "load x slip speed".
We are ensuring that our capacity is utilized effectively.

Furthermore, as shown in Figure 8, we have adopted an acceleration logic that achieves both high fuel efficiency and agile construction, and a pitching logic that prevents unnecessary gear changes on the pitching road and improves pitching performance. . In addition, in the case of sudden acceleration, Skip Shift Logic skips the intermediate gear and shifts to a more appropriate gear, and Buri Shift Down Logic, which puts the lower gear in advance and waits in preparation for re-acceleration, is also adopted, which is unique to medium-sized trucks. It is designed to meet the needs of agile driving.

By the way, for agile driving, it's not just about acceleration.
Appropriate deceleration must be achieved when the accelerator is off, which is one of the drawbacks of automatic transmissions with torque converters; however, in the case of this automatic transmission 50, when the accelerator is off, , the current gear is maintained, and since the hydraulic clutch 51 does not slip, appropriate deceleration performance can be obtained.

This makes it easier to travel on long boardwalks.

Furthermore, this automatic transmission 50 performs temperature adaptive control. The hydraulic method has the above-mentioned advantages, but in order to always take advantage of these advantages, it is necessary to switch the control contents so as to cover changes in oil viscosity with respect to temperature.

To cope with this, the automatic transmission 50 employs a temperature logic as shown in FIG. 9.

For example, (1) in Figure 9 is for the purpose of preventing oil from flowing in advance in order to quickly warm up the oil at low temperatures and to prevent start-up shock due to delayed oil inflow. , (3) are for the purpose of preventing gear noise at low temperatures. The adoption of this logic makes it easier to drive immediately after starting than a manual transmission vehicle in the lower temperature range where the engine can be started.

Adoption of such logic provides so-called easy drive performance, which provides better drivability than a manual transmission.

That is, this automatic transmission 50 is evaluated from the viewpoints of easy drive performance and economic efficiency.

In order to evaluate its easy drive performance, the easy drive rate is defined as how much the number of required driving operations is reduced in a manual transmission vehicle.
If expressed as a percentage, this automatic transmission 50 is:
Better than electronically controlled transmissions.

Furthermore, in order to evaluate its economic efficiency, if we compare the fuel consumption rates, the fuel consumption of this automatic transmission 50 is about the same as that of a manual transmission.

Advantages and Benefits of the Invention As can be seen from the foregoing, compared to pressure sensors that have already been proposed and used, the differential pressure sensor of the present invention has the advantage that high and low measured pressures can be measured by a piston and a cylinder body. A beam or a piston rod is deformed by the piston, and a strain gauge is introduced into a high-pressure side cylinder chamber and a low-pressure side cylinder chamber partitioned into the cylinder bore of the beam or piston. - Since the differential pressure sensor of the present invention is in a position where it is distorted by the rod, the hydraulic pressure in the hydraulic circuit is controlled by the effective pressure, without being affected by changes in back pressure caused by temperature. That is, it can be sensed as an effective pressure, and errors in the control of the hydraulic circuit due to back pressure changes due to temperature changes can be avoided, and it can be used in power steering, hydraulic clutches, transmissions, automatic transmissions, etc. In particular, with the structure in which a beam or piston rod is elastically deformed by a piston-cylinder, it becomes very simple and easy to apply to such hydraulic circuits.

Further, in the automatic transmission of the present invention, the oil spray type hydraulic clutch includes a high-pressure side cylinder chamber and a low-pressure side cylinder chamber that are partitioned into the cylinder by a piston, and has a flywheel so as to move a pressure plate. a hydraulic clutch control cylinder disposed in the wheel; a mechanical transmission having a shift cylinder, a shift valve, a select cylinder, and a select valve; and a system control hydraulic circuit controlling the hydraulic clutch;・High-pressure side and low-pressure side clutch control hydraulic piping connected to the high-pressure side and low-pressure side cylinder chambers of the control cylinder, connected to the shift cylinder and select cylinder via the shift valve and select valve. The clutch oil spray circuit controls the amount of oil sprayed onto the clutch disc of the hydraulic clutch. It has an oil spray control valve that controls the flow rate, and a clutch transmission select valve that controls the high pressure side clutch.
A pressure control valve is located in the control hydraulic line and includes a pressure control pilot valve for its low pressure side clutch.
A differential pressure sensor is placed in the control hydraulic piping, and a differential pressure sensor connects the high pressure side and low pressure side clutch control hydraulic piping to the high pressure side cylinder chamber and the low pressure side cylinder chamber, which are partitioned into the cylinder bore of the cylinder body by the piston. A low measuring pressure is guided correspondingly, the piston deforms a beam or a piston rod, and the beam or piston rod distorts a strain gauge to sense the clutch differential pressure. In addition to its differential pressure sensor, the electronic control unit also controls the select lever position sensor, accelerator position sensor, engine speed sensor, brake oil pressure sensor, gear position sensor, and This is where the signal from the vehicle speed sensor is input to control the shift valve, select valve, and pressure control pilot valve.
In the automatic transmission of this invention, the hydraulic pressure of its system control hydraulic circuit can be adjusted by its single pressure control valve, reducing shift time and improving shift agility, and using a mechanical friction clutch. and mechanical transmission combinations are now possible.
In addition, these hydraulic circuits can be controlled without being affected by changes in back pressure caused by temperature. In other words, errors in the control of the hydraulic circuits are avoided, and reliability and reliability are improved accordingly. Efficiency, fuel consumption and economy are improved, and in addition, drivability is improved, so-called easy driving.
The drivability is improved, and as a result, the adaptability for commercial bundles is improved.Furthermore, the automatic transmission of the present invention is characterized in that the trigger spring is located in its low-pressure side cylinder chamber, and immediately before the clutch is engaged, In the high-pressure side cylinder chamber, the hydraulic pressure acting on the piston is stepped up, making it possible to detect clutch engagement using hydraulic pressure, making it possible to start and shift gears with a slight latch stroke, and shift time. The electro-hydraulic control becomes more reliable and easier, and the mechanical
Friction clutch and mechanical transmission combinations can now be automated more easily,
Performance such as drivability and power performance is further improved.Furthermore, in the automatic transmission device of the present invention, the throttle passage is formed in either the cylinder or the piston of the hydraulic clutch control cylinder, and the throttle passage is formed in either the cylinder or the piston of the hydraulic clutch control cylinder. Since a slight flow of pressure oil is generated from the chamber to the low-pressure side cylinder chamber, air bubbles mixed in the pressure oil are discharged from the hydraulic circuit, and smooth engagement and engagement of the clutch and gear shifting of the transmission are achieved. In the automatic transmission of the present invention, the flex plate fixedly connects the flywheel of the hydraulic clutch to the crankshaft of the engine, so that power transmission is smooth. The system con'I
- Since the o-le hydraulic circuit is equipped with a check valve and a back pressure valve, hydraulic fluctuations in the clutch control hydraulic circuit are suppressed, and the clutch is smoothly engaged and engaged.Furthermore, the automatic transmission of the present invention , whose system control hydraulic circuit has stop valves, short circuit valves, and short circuit valves.
Since it is equipped with an and-stop control valve, when the hydraulic clutch cuts off the transmitted torque, the hydraulic clutch is instantly disengaged, further shortening the shifting time and further improving the agility of shifting. For this reason, it has applicability to various automobiles, and is particularly useful for commercial vehicles.

As for the relationship between the invention and the specific examples, from the specific examples of the present invention described with reference to the drawings, various design modifications will be apparent to those who have ordinary knowledge in the technical field to which this invention pertains. Further, the contents of this invention are essential to the establishment of the invention for accomplishing the task of the invention, and are derived from the technical essence of the invention which is the nature of the invention. and can be easily replaced with a form that is objectively recognized as incorporating it.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a specific example of the differential pressure sensor of the present invention, FIG. 2 is a schematic diagram of another specific example of the differential pressure sensor of the present invention,
FIG. 3 is an electrical system diagram of the automatic transmission of the present invention applied to a medium-sized truck, FIG. 4 is a hydraulic circuit diagram of the automatic transmission shown in FIG. 3, and FIG. 5 is a diagram of the automatic transmission shown in FIG. An axial cross-sectional view of a hydraulic clutch used in the automatic transmission shown in
Fig. 6 is a front view of the flywheel-ring piston (clutch piston) used in the hydraulic clutch shown in Fig. 5; Fig. 7 is a diagram showing the starting characteristics of this automatic transmission; FIG. 8 is a diagram showing the acceleration-uphill logic of this automatic transmission, and FIG. 9 is a diagram showing the temperature logic for adaptive control of this automatic transmission. 1131...Cylinder body, 12.32...Cylinder bore, 13.33...Piston, 16...
Elastic beam, 17.17...Strain gauge, 34.
...Piston rod, 51...Oil spray type hydraulic clutch, 52...Counter shaft type transmission, 53...Shift cylinder, 54...
・Select cylinder, 55.56...Shift solenoid valve, 57,58.59...Select solenoid valve, 60...System control hydraulic circuit, 61...High pressure side clutch control Hydraulic piping, 62... Low pressure side clutch control hydraulic piping, 63... Transmission control hydraulic piping, 65... Clutch oil spray circuit,
66...Oil spray control valve,
67...Clutch transmission select
Valve, 6th...Pressure control valve, 69...Pressure control pilot valve, 70...Check valve, 71
...Back pressure valve, 72...Stop valve, 73...Short circuit valve, 74...Short and stop control valve, 75...Electronic control unit . Figure 0 Figure 5 Figure O) Quiet 1. 1R rect IC for Shinshi'hei Beakhii γ) 1st round diagram r 组door completed is wrong Ma Noah.

Claims (7)

[Claims] (1) Measured high and low pressures are guided by a piston into a high-pressure side cylinder chamber and a low-pressure side cylinder chamber defined in the cylinder bore of the cylinder body, and the beam or piston rod is Differential pressure sensor where the strain gauge is deformed and strained with its beam or piston rod. (2) an oil cylinder having a high-pressure side cylinder chamber and a low-pressure side cylinder chamber partitioned into the cylinder by a piston, and a hydraulic clutch control cylinder disposed on the flywheel to move the pressure plate; A spray-type hydraulic clutch, a mechanical transmission having a shift cylinder, a shift valve, a select cylinder, and a select valve, and correspondingly connected to the high-pressure side and low-pressure side cylinder chambers of the hydraulic clutch control cylinder. Flow rate of hydraulic pressure discharged from the high-pressure side and low-pressure side clutch control hydraulic piping, the transmission control hydraulic piping connected to the shift cylinder and select cylinder via its shift valve and select valve, and the hydraulic pump. A system control hydraulic circuit with a flow control valve that controls the flow control valve and an oil spray control valve that controls the flow rate of oil sprayed onto the clutch disc of the hydraulic clutch.
a clutch oil spray circuit having a valve, a clutch transmission select valve located in its high pressure side clutch control hydraulic line, and a pressure control pilot valve located in its low pressure side clutch control hydraulic line; A pressure control valve having a valve, and a high-pressure side cylinder chamber and a low-pressure side cylinder in which measured pressures of high pressure and low pressure are partitioned into a cylinder bore of a cylinder body by a piston from the high-pressure side and low-pressure side clutch control hydraulic piping. guided into the chamber, the beam or piston rod is deformed by the piston,
Then, the strain gauge is strained by the beam or the piston rod to detect the clutch differential pressure, and in addition to the differential pressure sensor, the select lever position sensor, the accelerator position sensor, Electronic control that inputs signals from sensors, engine speed sensor, brake oil pressure sensor, gear position sensor, and vehicle speed sensor to control the shift valve, select valve, and pressure control pilot valve.・Automatic transmission including unit. (3) an oil cylinder having a high-pressure side cylinder chamber and a low-pressure side cylinder chamber partitioned into the cylinder by a piston, and a hydraulic clutch control cylinder disposed on the flywheel to move the pressure plate; A spray-type hydraulic clutch, a mechanical transmission having a shift cylinder, a shift valve, a select cylinder, and a select valve, and correspondingly connected to the high-pressure side and low-pressure side cylinder chambers of the hydraulic clutch control cylinder. high-pressure side and low-pressure side clutch control hydraulic piping, transmission control hydraulic piping connected to its shift cylinder and select cylinder via its shift valve and select valve, and pressure oil discharged from the hydraulic pump. A system control hydraulic circuit with a flow control valve that controls the flow rate and an oil spray control valve that controls the flow rate of oil sprayed onto the clutch disc of the hydraulic clutch.
a clutch oil spray circuit having a valve, a clutch transmission select valve located in its high pressure side clutch control hydraulic line, and a pressure control pilot valve located in its low pressure side clutch control hydraulic line; a pressure control valve having a valve; a trigger spring disposed in the low-pressure cylinder chamber of the pressure control valve, which steps up the hydraulic pressure acting on the piston in the high-pressure cylinder chamber in a stepwise manner immediately before the clutch is connected; High pressure and low pressure measurement pressures are guided from the high pressure side and low pressure side clutch control hydraulic piping to high pressure side cylinder chambers and low pressure side cylinder chambers defined in the cylinder bore of the cylinder body by pistons, and the beam or , the piston rod is deformed by the piston,
Then, the strain gauge is strained by the beam or the piston rod to detect the clutch differential pressure, and in addition to the differential pressure sensor, the select lever position sensor, the accelerator position sensor, Electronic control that inputs signals from sensors, engine speed sensor, brake oil pressure sensor, gear position sensor, and vehicle speed sensor to control the shift valve, select valve, and pressure control pilot valve.・Automatic transmission including unit. (4) an oil cylinder having a high-pressure side cylinder chamber and a low-pressure side cylinder chamber partitioned into the cylinder by a piston, and having a hydraulic clutch control cylinder disposed on the flywheel to move the pressure plate; A spray-type hydraulic clutch, a mechanical transmission having a shift cylinder, a shift valve, a select cylinder, and a select valve, and correspondingly connected to the high-pressure side and low-pressure side cylinder chambers of the hydraulic clutch control cylinder. high-pressure side and low-pressure side clutch control hydraulic piping, transmission control hydraulic piping connected to its shift cylinder and select cylinder via its shift valve and select valve, and pressure oil discharged from the hydraulic pump. A system control hydraulic circuit with a flow control valve that controls the flow rate and an oil spray control valve that controls the flow rate of oil sprayed onto the clutch disc of the hydraulic clutch.
a clutch oil spray circuit having a valve, a clutch transmission select valve located in its high pressure side clutch control hydraulic line, and a pressure control pilot valve located in its low pressure side clutch control hydraulic line; A pressure control valve having a valve, and a throttle passage formed in either the cylinder or the piston of the hydraulic clutch control cylinder to produce a slight flow of pressure oil from the high pressure side cylinder chamber to the low pressure side cylinder chamber. Then, the measured high and low pressures are guided from the high-pressure side and low-pressure side clutch control hydraulic piping to the high-pressure side cylinder chamber and low-pressure side cylinder chamber defined in the cylinder bore of the cylinder body by the piston, and the beam , or the piston rod is
It is deformed by the piston, and the strain gauge is
A differential pressure sensor that detects clutch differential pressure by being distorted by the beam or piston rod, and in addition to that differential pressure sensor, a select lever position sensor, an accelerator position sensor, and an engine rotation speed sensor. , a brake oil pressure sensor, a gear position sensor, and an electronic control unit that receives signals from a vehicle speed sensor to control its shift valve, select valve, and pressure control pilot valve. gearbox. (5) an oil cylinder having a high-pressure side cylinder chamber and a low-pressure side cylinder chamber partitioned into the cylinder by a piston, and having a hydraulic clutch control cylinder disposed on the flywheel to move the pressure plate; A spray-type hydraulic clutch, a mechanical transmission having a shift cylinder, a shift valve, a select cylinder, and a select valve, and correspondingly connected to the high-pressure side and low-pressure side cylinder chambers of the hydraulic clutch control cylinder. high-pressure side and low-pressure side clutch control hydraulic piping, transmission control hydraulic piping connected to its shift cylinder and select cylinder via its shift valve and select valve, and pressure oil discharged from the hydraulic pump. A system control hydraulic circuit with a flow control valve that controls the flow rate and an oil spray control valve that controls the flow rate of oil sprayed onto the clutch disc of the hydraulic clutch.
a clutch oil spray circuit having a valve, a clutch transmission select valve located in its high pressure side clutch control hydraulic line, and a pressure control pilot valve located in its low pressure side clutch control hydraulic line; a pressure control valve having a valve and a flex plate that fixedly connects the flywheel of its hydraulic clutch to the engine crankshaft; The pipe is guided by a piston to a high pressure side cylinder chamber and a low pressure side cylinder chamber defined in the cylinder bore of the cylinder body, and the beam or piston rod is deformed by the piston.
Then, the strain gauge is strained by the beam or the piston rod to detect the clutch differential pressure, and in addition to the differential pressure sensor, the select lever position sensor, the accelerator position sensor, Electronic control that inputs signals from sensors, engine speed sensor, brake oil pressure sensor, gear position sensor, and vehicle speed sensor to control the shift valve, select valve, and pressure control pilot valve.・Automatic transmission including unit. (6) an oil cylinder having a high-pressure side cylinder chamber and a low-pressure side cylinder chamber partitioned into the cylinder by a piston, and having a hydraulic clutch control cylinder disposed on the flywheel to move the pressure plate; A spray-type hydraulic clutch, a mechanical transmission having a shift cylinder, a shift valve, a select cylinder, and a select valve, and correspondingly connected to the high-pressure side and low-pressure side cylinder chambers of the hydraulic clutch control cylinder. high-pressure side and low-pressure side clutch control hydraulic piping, transmission control hydraulic piping connected to its shift cylinder and select cylinder via its shift valve and select valve, and pressure oil discharged from the hydraulic pump. A system control hydraulic circuit with a flow control valve that controls the flow rate and an oil spray control valve that controls the flow rate of oil sprayed onto the clutch disc of the hydraulic clutch.
a clutch oil spray circuit having a valve, a clutch transmission select valve located in its high pressure side clutch control hydraulic line, and a pressure control pilot valve located in its low pressure side clutch control hydraulic line; a pressure control valve having a valve; a check valve disposed in the high-pressure side clutch control hydraulic line upstream of the clutch transmission select valve; and a check valve disposed in the low-pressure side of the pressure control valve downstream of the pressure control valve; A back pressure valve is placed in a branch pipe that branches off from the clutch control hydraulic pipe, and high and low pressure measurement pressures are transferred from the high pressure side and low pressure side clutch control hydraulic pipe to the cylinder body of the cylinder body by a piston. The beam or the piston rod is guided into a high pressure side cylinder chamber and a low pressure side cylinder chamber divided in the bore, and is deformed by the piston.
Then, the strain gauge is strained by the beam or the piston rod to detect the clutch differential pressure, and in addition to the differential pressure sensor, the select lever position sensor, the accelerator position sensor, Electronic control system that inputs signals from the sensor, engine speed sensor, brake oil pressure sensor, gear position sensor, and vehicle speed sensor to control the shift valve, select valve, and pressure control pilot valve. Automatic transmission including unit and. (7) An oil cylinder having a high-pressure side cylinder chamber and a low-pressure side cylinder chamber partitioned into the cylinder by a piston, and having a hydraulic clutch control cylinder disposed on the flywheel to move the pressure plate. A spray-type hydraulic clutch, a mechanical transmission having a shift cylinder, a shift valve, a select cylinder, and a select valve, and correspondingly connected to the high-pressure side and low-pressure side cylinder chambers of the hydraulic clutch control cylinder. high-pressure side and low-pressure side clutch control hydraulic piping, transmission control hydraulic piping connected to its shift cylinder and select cylinder via its shift valve and select valve, and pressure oil discharged from the hydraulic pump. A system control hydraulic circuit with a flow control valve that controls the flow rate and an oil spray control valve that controls the flow rate of oil sprayed onto the clutch disc of the hydraulic clutch.
a clutch oil spray circuit having a valve, a clutch transmission select valve located in its high pressure side clutch control hydraulic line, and a pressure control pilot valve located in its low pressure side clutch control hydraulic line; a pressure control valve having a valve; a stop valve disposed in the high pressure side clutch control hydraulic line downstream of the clutch transmission select valve; A short-circuit valve located downstream of the valve and the pressure that operates the stop valve and the short-circuit valve located at the point in the low-pressure side clutch control hydraulic piping that connects the downstream side of the valve to the downstream side of the pressure control valve. A short-and-stop control valve that controls the oil and high-pressure and low-pressure measured pressures are partitioned into the cylinder bore of the cylinder body by pistons from its high-pressure and low-pressure side clutch control hydraulic piping. A beam or a piston rod is deformed by the piston, and a strain gauge is strained by the beam or piston rod to increase the clutch differential pressure. In addition to the differential pressure sensor, there are also signals from the select lever position sensor, accelerator position sensor, engine speed sensor, brake oil pressure sensor, gear position sensor, and vehicle speed sensor. An automatic transmission that includes an electronic control unit that receives signals to control its shift valve, select valve, pressure control pilot valve, and short-and-stop valve.