JP2519547B2 - Hydraulic crimp clutch - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic pressure-contact type clutch, and more particularly, to use a shape memory alloy compression spring for actuating a valve body that restricts a stroke of a piston for pressing a pressure plate. As a result, when the temperature is high, the stroke of the piston can be reduced to quickly engage and disengage the clutch, and when the temperature is low, the stroke of the piston can be increased to prevent the drag of the clutch due to an increase in the viscosity of the oil. In addition, the present invention relates to a hydraulic pressure-bonding clutch in which the clutch is made compact and the number of parts is reduced by providing a simple valve device having a structure for operating the valve element inside the piston.

2. Description of the Related Art Conventionally, in a manual transmission type transmission or a transmission in which the manual transmission type transmission is automatically shifted by an actuator employing a fluid pressure cylinder, a mechanical clutch such as a dry type or a wet type is required. In order to improve the durability and to quickly connect and disconnect the clutch, a hydraulic pressure type clutch is adopted.

However, in the conventional hydraulic pressure-type clutch, since the distance between the clutch cover and the clutch disk is always constant, the stroke of the piston for pressing the pressure plate is constant. The clutch becomes worse,
So-called clutch dragging occurs, and the torque resulting from the clutch dragging increases, causing problems such as difficulty in engaging the gear and difficulty in disengaging the gear. Further, in order to solve this problem, it is conceivable to increase the stroke of the piston, but this causes a problem that the engagement and disengagement of the clutch becomes slow at a high temperature and it becomes impossible to perform a speed change operation. In addition, it is difficult to dispose such a complicated and large-sized device inside the clutch in order to eliminate such a problem, because it causes an increase in the number of parts and the space inside the clutch is very small. There is an inconvenience of making the vehicle longer and deteriorating the vehicle mountability.

The present invention was made in order to eliminate the above-mentioned drawbacks of the prior art. The purpose of the present invention is to fix the main body fixed to the crankshaft of the engine and the pressure plate pressing inside the main body. A hydraulic device comprising a cylinder having a cylinder chamber in which a ring-shaped piston for sliding is accommodated and having a communication hole for communicating an oil passage with the cylinder chamber, and a hydraulic pump for supplying oil to the cylinder. In a hydraulic pressure-bonding type clutch provided with the valve body, the valve body is housed in the piston and relatively slides in the piston to limit the stroke of the piston, and a bias compression spring for biasing the valve body toward the piston. And a compression spring made of a shape memory alloy, which is memorized so that the valve body is pressed and urged toward the communication hole to expand when the temperature changes. Inside the piston, the compression spring made of shape memory alloy returns to its memory form at high temperature, and the valve element slides in the direction of the through hole to reduce the stroke of the piston, and at low temperature, the bias pressure continuous spring. The shape memory alloy compression spring is compressed by this to draw the valve element toward the piston side to increase the stroke of the piston, thereby preventing the clutch from dragging at low temperatures. The purpose of this is to allow the gears to be put in and taken out easily at the time. Another object of the present invention is to make it possible to quickly engage and disengage the clutch at a high temperature with the above configuration. Yet another purpose is
By equipping the inside of the piston with a valve device consisting of only three parts that limit the stroke of the piston,
The object of the present invention is to improve the vehicle mountability of the clutch by reducing the number of parts and preventing the clutch from dragging at a low temperature without increasing the total length of the clutch.

In summary, the present invention has a main body fixed to a crankshaft of an engine, a cylinder chamber fixed to the main body and in which a ring-shaped piston for pressing a pressure plate is slidably accommodated, and an oil passage is provided. In a hydraulic pressure-bonding type clutch including a hydraulic device including a cylinder having a communication hole communicating with the cylinder chamber and a hydraulic pump supplying oil to the cylinder, the hydraulic pressure contact clutch is housed in the piston and relatively slides in the piston. A valve body for limiting the stroke of the piston, a bias compression spring for biasing the valve body toward the piston, and a biasing force for pushing the valve body toward the communication hole to change the temperature. A valve device consisting of a compression spring made of a shape memory alloy, which is made to remember to expand, is provided inside the piston, and when the temperature is high, the shape description is made. When the alloy compression spring returns to its memory form, the valve body slides in the direction of the communication hole to reduce the stroke of the piston, and at the time of low temperature, the bias compression spring causes the shape memory alloy compression spring to move. It is characterized in that the valve body is compressed and drawn into the piston side to increase the stroke of the piston.

Hereinafter, the present invention will be described based on embodiments shown in the drawings. In FIG. 1, a hydraulic pressure bonding type clutch 1 according to the present invention
A main body 14 fixed to the crankshaft 6 of an engine (not shown) and a pressure plate
A cylinder 15 having a cylinder chamber 15b in which a pressing ring-shaped piston 16 for pressing is slidably accommodated and having a communication hole 15d for communicating the oil passage 15c with the cylinder 15 and oil are supplied to the cylinder. A hydraulic device 12 comprising a vane pump 18 which is an example of a hydraulic pump,
A valve device 54 including a valve body 50, a bias compression spring 52, and a shape memory alloy compression spring 53 is provided inside the piston 16.

First, the basic configuration of the hydraulic pressure-type clutch 1 will be described. A crankshaft 6 of an engine (not shown) is slidably fitted in a clutch housing 5.
A flex plate 9 is fixed to one end of the crankshaft 6 by bolts 8 and protrudes into the clutch housing 5. The flex plate 9 has a hydraulic device 12 for pressing a pressure plate 10 against a clutch disk 11. Are fixed by bolts 13.

The hydraulic device 12 includes a main body 14, a cylinder 15, a ring-shaped piston 16, and a vane pump 18 as an example of a hydraulic pump.

The main body 14 is formed in a circular shape so as to be rotatable together with the flex plate 9, is fixed to the flex plate 9 by bolts 13, and an input shaft 20 is rotatably mounted at the center portion thereof via a bearing 19, and a clutch is provided. A friction member 21 is fixed to the facing surface 14a on the disk 11 side.

The cylinder 15 is formed in a circular shape so as to be rotatable together with the main body 14, is fixed to the main body 14 by bolts 22, and has a cylinder chamber 15b and an oil passage 15c communicating therewith. The cylinder chamber 15b and the oil passage 15c are communicatively connected by a communication hole 15d, the oil passage 15c is rotatably supported by the sleeve 18a of the vane pump 18 via the bearing 23, and the boss portion 18b of the vane pump 18 has a plurality of sealing members. Oil passage 26 of retainer 26 rotatably fitted through 24 and 25
The retainer 26 is communicatively connected to a, and the retainer 26 is fixed to the cylinder 15 via a seal member 27. The oil passage 26a of the retainer 26 is connected to the oil discharge port 18c of the vane pump 18 via an electromagnetic valve (not shown) housed in an electromagnetic valve housing 18f fixed to the boss 18b of the vane pump 18. The oil discharged from the vane pump communicates with the oil gallery 18d.
Retainer 26 from high pressure side oil gallery 18g formed in b
Is supplied in a high-pressure state through a communication hole 26d formed in the hole. The end of the oil passage 15c is sealed by a steel ball 15e.

In the cylinder 15, an oil passage 15f is formed at a circumferential position different from the oil passage 15c, and the oil passage is connected to a space 12a in the hydraulic device 12 through a communication hole 15g. The oil passage 26c communicates with an oil passage 26c formed at a circumferential position different from the oil passage 26a. The oil passage 26c communicates with an oil gallery 18d via another solenoid valve (not shown). The oil discharged from the low pressure side oil gallery 18h formed in the boss 18b is controlled by the solenoid valve and supplied to the space 12a in a low pressure state through the communication hole 26e formed in the retainer 26, and the clutch is operated. Hydraulic pressure for cutting can be obtained.

The oil in the space 12a is discharged from a communication hole 15h communicating with an oil suction port (not shown) of the vane pump 18, and is sucked into the oil suction port of the vane pump 18.

The piston 16 is formed in a ring shape, and the pressure plate 10 is provided on the side surface 16a on the clutch disc 11 side.
Is fixed, and the cylinder chamber 15 is
b, is slidably received in the horizontal direction, and moves to the left in the figure to move the pressure plate 10 to the clutch disk 11
Is configured to be pressed.

The counter shaft 42 is rotatably supported by the transmission case 41 via a bearing 43.

Referring also to FIG. 2, the vane pump 18 is fixed to the clutch housing 5 by bolts 28, and its main body 18e is
It is divided and connected by bolts 29, and the rotor 30 is
Are rotatably accommodated by being supported by the sleeve 18a via the bush 31. The rotor 30 is housed in a ring 32, and a vane 33 slidably housed in a plurality of radial grooves 30a formed in the rotor 30 is attached to an inner surface 32a of the ring by centrifugal force accompanying rotation. The oil can be compressed while sliding while making contact with and keeping confidentiality. Two cutouts 30b for power transmission are provided on the inner surface of the rotor 30.
Is formed, the end portion 26b of the retainer 26 is engaged with the notch,
Power is transmitted from the retainer to the rotor 30.

The center of the ring 32 and the rotation center of the rotor 30 are eccentric by a predetermined eccentric amount, and the eccentric amount is variable.
That is, a compression spring 34 for pressure setting that presses and urges the ring pressing pin 47 is provided on the side of the main body 18e of the vane pump 18 with a bolt 35.
The compression spring is housed in a cover 36 fixed to the main body by
The eccentric amount is reduced by compressing 34 by the ring 32. Further, a stopper 37 is fixed to the inner peripheral surface 32a of the ring 32, and the vertical position of the ring 32 is set by the stopper.

Next, a compression spring made of a shape memory alloy which is a main part of the present invention
The structure of the valve device 54 using the 53 will be described. The valve device is mounted at three positions at equal intervals in the circumferential direction of the piston 16 as shown in FIG. It is designed to be completely housed in the recessed portion 16c formed on the side surface, and is configured so as not to project from the side surface 16b at all, and as shown in FIG.
50, bias compression spring 52, and shape memory alloy compression spring 53
Consists of

The valve body 50 is housed in the piston 16 and relatively slides in the piston in the axial direction of the crankshaft 6 so that its tip 50a blocks the communication hole 15d and limits the stroke of the piston 16. It is made hollow, and the cylindrical part
50b and a flange portion 50c formed at one end of the cylindrical portion and the tip
A valve portion 50d formed in 50a and a hole 50e for accommodating the shape memory alloy compression spring 53 are formed. The diameter of the valve portion 50d is formed to be larger than the diameter of the communication hole 15d. 15d
When pressed against, the communication hole is shielded by the tip 50a.

The bias compression spring 52 is configured to urge the valve body 50 toward the piston 16, and is a normal metal spring that is not a shape memory alloy, and is attached to the cylindrical portion 50b of the valve body 50. One end 52a thereof abuts the flange portion 50c of the valve body 50,
The other end 52b abuts a lid member 55 formed in a substantially rhombic shape having the same shape as the recess 16c, and is accommodated in the recess 16c. The spring constant is the shape memory alloy compression spring 53.
The compression force is weaker than the restoring force to the memory form (expanded state) of No. 3, and when the shape memory alloy compression spring 53 returns to the secondary permanent deformation processing form (compressed state), the shape memory alloy compression spring is compressed. It is set to a value that you can get.

The lid member 55 has a hole 55a into which the cylindrical portion 50b of the valve body 50 is fitted, and is fixed to the piston 16 by two screws 56, respectively, and when the lid member is mounted on the piston 16, the surface 55b thereof is a piston. It is designed to be flush with the side 16 of the 16.

The compression spring 53 made of a shape memory alloy is housed in the hole 50e of the valve body 50, and is stored in such a manner that the valve body 50 is pressed and urged toward the communication hole 15d and expanded by a change in temperature. Thus, the expanded state is manufactured as a storage mode, and the compressed state is manufactured as a secondary permanent deformation mode. That is, when the temperature exceeds a certain value, the shape returns to the memory form, and therefore, the shape memory alloy compression spring 53 tries to expand by generating a very strong extension force, and when the temperature becomes less than the certain value, the secondary permanent deformation occurs. The force to maintain the stretched state is lost so that the working form may be restored.

Shape memory alloys are roughly divided into Ni-Ti alloys and Cu-Zn-Al alloys, but Cu-Zn-Al alloys are cheaper than Ni-Ti alloys, have fast trackability to temperature changes, and have hysteresis. Has the advantage of being small and having a wide transformation temperature range,
The Ni-Ti alloy is said to have a large shape recovery amount, a high durability (thermal cycle) of about two digits, excellent functional properties, and high reliability. In the present invention, any of these alloys can be used for the compression spring 53 made of a shape memory alloy.

When the shape memory alloy compression spring 53 returns to its memory form at high temperature, the valve body 50 slides in the direction of the communication hole 15c to shield the communication hole to reduce the stroke of the piston 16, and when the temperature is low, the bias is applied. The compression memory 52 is configured to compress the shape memory alloy compression spring 53, pull the valve body 50 toward the piston side, open the communication hole 15d, and increase the stroke of the piston 16.

The present invention is configured as described above, and its operation will be described below. First, the basic operation of the hydraulic pressure-bonding type clutch 1 will be described. When the engine rotates, the crankshaft 6, the flex plate 9, the hydraulic device 12
Body 14, cylinder 15, retainer 26 and vane pump 18
The rotor 30 rotates at the same speed, and the increased pressure oil is discharged from the vane pump 18.

In the state shown in FIG. 1, the oil from the vane pump 18 passes through the low-pressure side oil gallery 18h, the oil passage 26c, the oil passage 15f, and the communication hole 15g, and is depressurized by the electromagnetic valve and supplied only to the space 12a. Is filled with low-pressure oil and is not supplied to the oil passage 26a and the oil passage 15c. Therefore, the pressure plater 10 and the piston 16 are pressed rightward in the drawing by the low-pressure oil filled in the space 12a, the clutch disc 11 is released, and the clutch is disengaged.

Therefore, when the clutch is connected, the solenoid valve operates to connect the discharge port 18c of the vane pump 18 and the oil passage 26a, and high-pressure oil flows into the oil passage 26a from the high-pressure oil gallery 18g through the communication hole 26d. Then, the high-pressure oil is supplied from the oil passage 26a to the oil passage 15c. Then, the oil flows into the cylinder chamber 15b through the communication hole 15d, high-pressure hydraulic pressure is generated in the cylinder chamber, and the piston 16 moves leftward in the drawing together with the pressure plate 10 and the clutch disc 11 Is pressed against the friction member 21 of the main body 14, power is transmitted to the clutch disc 11, and the clutch is engaged.

Also, by preventing the oil of the vane pump 18 from being supplied to the oil passage 15c by the operation of the solenoid valve,
The hydraulic pressure in the cylinder chamber 15b is released, and the clutch can be disengaged by pushing the pressure plate 10 and the piston 16 back to the right in the drawing by the low-pressure hydraulic pressure in the space 12a.

Next, a compression spring made of a shape memory alloy which is a main part of the present invention
The operation of the valve device 54 using 53 will be described. Sixth
In the figure, at the time of high temperature, the shape memory alloy compression spring 53
Tries to return to its memory form strongly,
When the valve 50 is pressed, the valve portion 50b of the tip 50a of the valve body comes into contact with the communication hole 15d of the cylinder 15. As a result, the communication hole 15d is shielded by the tip 50a of the valve body 50, the stroke of the piston 16 is limited, the pressure plate 10 approaches the clutch disc 11, and the gap C between the pressure plate 10 and the clutch disc 11 is reduced. It becomes smaller, and it becomes possible to promptly connect and disconnect the clutch.

At low temperature, as shown in FIG. 7, the shape memory alloy compression spring 53 loses the force to return to its memory form, so that the restoring force of the bias compression spring 52 is superior, The compression spring 53 restores the shape memory alloy compression spring 53 from the expanded state to the compressed state, that is, the secondary permanent deformation processing state, and the tip 50a of the valve body 50 opens the communication hole 15d. As a result, the stroke of the piston 16 increases and the gap C between the pressure plate 10 and the clutch disc 11 increases, which prevents the clutch from dragging even if the oil viscosity increases at low temperatures. , The clutch is completely disengaged, and the gears are put in and taken out lightly, and the load on the actuator or the like using air can be reduced.

Further, in the present invention, since the valve device 54 is composed of only three parts, the number of parts can be reduced, and any of these parts can be mounted without protruding from the piston 16, so that the hydraulic pressure bonding type Since it is not necessary to increase the total length of the clutch 1 at all and the clutch 1 can be made compact, the vehicle mountability is good.

Advantageous Effects of Invention The present invention has the main body fixed to the crankshaft of the engine as described above, and the cylinder chamber fixed to the main body in which the ring-shaped piston for pressing the pressure plate is slidably accommodated, and In a hydraulic pressure-bonding type clutch provided with a hydraulic device including a cylinder having a communication hole for communicating an oil passage with the cylinder chamber and a hydraulic pump for supplying oil to the cylinder, the hydraulic pressure-bonding clutch is housed in the piston and relatively in the piston. A valve element that slides in the axial direction of the crankshaft to limit the stroke of the piston, a bias compression spring that biases the valve element toward the piston, and a bias element that presses the valve element toward the communication hole. A valve device consisting of a compression spring made of a shape memory alloy that is remembered to expand due to changes in temperature is provided inside the piston, and the shape is maintained at high temperatures. When the memory alloy compression spring returns to its memory mode, the valve body slides in the direction of the communication hole to reduce the stroke of the piston.When the temperature is low, the biasing compression spring compresses the shape memory alloy compression spring. Since the body is drawn to the piston side and the communication hole is opened to increase the stroke of the piston, there is an effect that it is possible to prevent the dragging of the clutch at low temperature, and as a result, gear shifting and The effect that the gear can be easily removed can be obtained.
Further, the above configuration has an effect that the clutch can be quickly connected and disconnected at a high temperature. Furthermore, since the valve device consisting of only three parts that limits the stroke of the piston is provided inside the piston, while reducing the number of parts, the clutch drags at low temperatures without increasing the total length of the clutch at all. There is an effect that it can be prevented and the vehicle mountability of the clutch can be improved.

[Brief description of drawings]

The drawings relate to an embodiment of the present invention. FIG. 1 is a vertical sectional view of a hydraulic pressure-bonding type clutch, FIG. 2 is a vertical sectional view of a vane pump, and FIG. 3 is a front view of a piston equipped with a valve device.
FIG. 7 is a partially broken transverse sectional view of a piston showing a valve device, FIG. 5 is an exploded perspective view of the valve device, FIG. 6 is a longitudinal sectional view of an essential part showing an operating state of the valve device at a high temperature, and FIG. FIG. 6 is a longitudinal sectional view of an essential part showing the operating state of the valve device at the time. 1 is a hydraulic pressure type clutch, 6 is a crankshaft, 10 is a pressure plate, 12 is a hydraulic device, 15 is a cylinder, 15
b is a cylinder chamber, 15c is an oil passage, 15d is a communication hole, 16 is a piston, 18 is a vane pump as an example of a hydraulic pump, 50
Is a valve body, 50a is a tip, 52 is a bias compression spring, 53 is a shape memory alloy compression spring, and 54 is a valve device.

Claims (1)

(57) [Claims] 1. A main body fixed to a crankshaft of an engine, and a cylinder chamber fixed to the main body, in which a ring-shaped piston for pressing a pressure plate is slidably accommodated, and an oil passage is provided in the cylinder. A hydraulic pressure-bonding type clutch including a hydraulic device including a cylinder having a communication hole for communicating with a chamber and a hydraulic pump for supplying oil to the cylinder, wherein the clutch is housed in the piston and relatively slides in the piston. A valve element that limits the stroke of the piston, a bias compression spring that presses and biases the valve element toward the piston, and a valve element that presses and biases the valve element toward the communication hole and expands due to a change in temperature. A valve device consisting of a compression spring made of a shape memory alloy that has been memorized as described above is provided inside the piston, and at the time of high temperature, the compression memory made of the shape memory alloy is used. By returning to the memory form, the valve body slides in the direction of the communication hole to reduce the stroke of the piston, and at the time of low temperature, the compression spring made of the shape memory alloy is compressed by the compression spring for bias. A hydraulic pressure-bonding clutch, wherein the valve body is drawn toward the piston to increase the stroke of the piston.