JPH03186615A - Hydraulically pressing type clutch - Google Patents

Abstract

PURPOSE:To prevent a clutch from being caught during low temperature operation, by providing such an arrangement that a shape memory alloy compression spring is compressed by a bias compression spring during low temperature operation, and accordingly a stopper is drawn toward a piston so as to open a communication hole, resulting in an increase in the stroke of the piston. CONSTITUTION:A valve device is composed of a valve element 50, a bias compression spring 52 and a shape memory alloy compression spring 53. The valve element 50 is adapted to slide toward a crank-shaft 6 and its forward end 50a blocks a communication hole 15c in order to limit the stroke of a piston 16. The bias compression spring 52 urges the valve element 50 toward the piston 16. During high temperature operation, the shape memory alloy compression spring 53 retrieves its memory shape so that the valve element 50 blocks the communication hole 15c to hydraulically lock a cylinder chamber 15b in order to decrease the stroke of the piston 16. During low temperature operation, the bias compression spring 52 compresses the shape memory alloy compression spring 53 so as to move the valve element 50 toward the piston, and accordingly, the communication hole 15c is opened to increase the stroke of the piston 16.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a hydraulic pressure bonding type clutch, and in particular, a compression type clutch made of a shape memory alloy is used to operate a valve body as a stopper that limits the stroke of a piston for pressing a pressure plate. By using a spring, the stroke of the piston is reduced when the temperature is high, allowing the clutch to be engaged and disconnected quickly, and the stroke of the piston is increased when the temperature is low, thereby preventing the clutch from dragging due to increased oil viscosity. This invention relates to a hydraulic crimp i-clutch that is designed to make the clutch more compact and reduce the number of parts by providing a simple valve device inside the Moston with a simple structure for operating the valve body.

BACKGROUND OF THE INVENTION Conventionally, in a transformer solution in which a manual transmission or a single manual transmission is automatically shifted by an actuator employing a hydraulic cylinder, dry or ? A mechanical clutch such as W'A is required, and in particular, a hydraulic compression type clutch is used to improve the durability of the crank 9 and to quickly connect and disconnect the clutch.

However, in conventional hydraulic compression clutches, the gap between the clutch cover and the clutch disc was always constant, so the stroke of the piston for pressure plate N pressure was constant, and as a result, the oil viscosity increased at low temperatures. Because the amount becomes so large, the clutch becomes difficult to disengage, resulting in what is known as a crack.

The clutch drag caused the clutch to drag, and the torque caused by this clutch drag increased, causing problems such as difficulty in engaging the gear, or difficulty in getting out of the gear even after it was engaged.

In order to solve this problem, it is conceivable to increase the stroke of the piston, but this causes the problem that the clutch engages and disengages slowly at high temperatures, making it impossible to perform speed change operations. Furthermore, it is difficult to install a complicated and large device inside the clutch in order to eliminate such problems because it increases the number of parts and the space inside the clutch is extremely narrow. This results in the inconvenience of making the length longer and impairing vehicle mountability.

Purpose The present invention has been made to eliminate the drawbacks of the prior art described above, and its objects are: - A main body fixed to the crankshaft of an engine; A hydraulic device comprising a cylinder having a cylinder chamber in which a ring-shaped piston is slidably housed and a communication hole for communicating an oil passage with the cylinder chamber, and a hydraulic pump for supplying oil to the cylinder. A hydraulic compression clutch equipped with a valve body that slides in the direction of the crankshaft and whose tip blocks the communication hole to limit the stroke of the piston, and a bias compression spring that biases the valve body toward the piston. The piston is equipped with a valve device consisting of a compression spring made of a shape memory alloy that presses the valve body toward the communication hole and is memorized to expand due to temperature changes. When the alloy compression spring returns to its memory state, the valve body closes the communication hole and hydraulically locks the cylinder chamber, reducing the piston stroke. At low temperatures, the bias compression spring activates the shape memory alloy compression spring. By configuring the stopper to be compressed and pulled toward the piston, opening the communication hole and increasing the stroke of the piston, the clutch is prevented from dragging at low temperatures, and this also prevents gear shifting at low temperatures. and to allow gear removal to be carried out easily. Another object is to enable the clutch to be quickly connected and disconnected at high temperatures with the above configuration. Another objective is to reduce the number of parts by equipping the inside of the piston with a valve device that limits the stroke of the piston and consists of only three parts. To improve the on-vehicle compatibility of a clutch by preventing the clutch from dragging.

Structure: In short, the present invention has a main body fixed to the 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 housed. In a hydraulic crimp-type clutch equipped with a hydraulic device consisting of a cylinder having a communication hole that communicates with a cylinder chamber and a hydraulic pump that supplies oil to the cylinder, the clutch slides in the direction of the crankshaft so that its tip is connected to the communication hole. a valve body that shields and limits the stroke of the piston; a bias compression spring that presses and biases the valve body toward the piston; and a bias compression spring that presses and biases the valve body toward the communication hole due to a change in temperature. A pulp device consisting of a compression spring made of a shape memory alloy which is memorized to be expanded is provided inside the piston, and when the temperature is high, the compression spring made of the shape memory alloy returns to its memorized state, thereby causing the valve body to close. The stroke of the piston is reduced by blocking the communication hole and hydraulically locking the cylinder chamber, and when the temperature is low, the bias compression spring compresses the shape memory alloy compression spring and the stopper moves toward the piston. The piston is characterized in that the piston is drawn in to open the communication hole and increase the stroke of the piston.

The present invention will be explained below based on embodiments shown in the drawings. 1st
In the figure, a hydraulic pressure bonding type clutch 1 according to the present invention includes a main body 14 fixed to a crankshaft 6 of an engine (not shown) and a ring-shaped piston 16 fixed to the main body for pressing a pressure plate 10 inside. A hydraulic cylinder 15 that has a cylinder chamber 15b that is slidably housed and has a communication hole 15d that communicates an oil passage 15c with the cylinder chamber, and a vane pump 18 that is an example of a hydraulic pump that supplies oil to the cylinder. The device 12 includes a valve body 5o and a bias compression spring 52.
A valve device 54 consisting of a compression spring 53 made of a shape memory alloy is provided inside the piston 16.

First, to explain the basic configuration of the hydraulic pressure bonding type clutch 1, an engine (not shown) is installed in the clutch housing 5.
A crankshaft 6 is slidably fitted and protrudes into the clutch housing 5, and a flex plate 9 is attached to one end of the crankshaft 6 by a bolt 8.
is fixed to the flex plate 9, and a hydraulic device 12 for press-fitting the pressure plate 10 to the clutch disk 11 is fixed to the flex plate 9 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, which is an example of a hydraulic pump.

The main body 14 is formed into a circular shape so as to be rotatable together with the flex plate 9, and is fixed to the flex plate 9 with bolts 13. An input shaft 20 is rotatably attached to the center of the main body 14 via a bearing 19, and the input shaft 20 is rotatably mounted to the center of the main body 14, and is rotatable with the flex plate 9. A friction member 21 is fixed to the opposing surface 14a on the disk II side.

The cylinder 15 is formed into a circular shape so as to be rotatable together with the main body 14, is fixed to the main body 14 by a bolt 22, and has a cylinder chamber 15b inside and an oil passage 15c communicating with the cylinder chamber 15b.
is formed. Cylinder chamber 15b and oil passage 15
c is connected to the oil passage 1 through the communication hole 15d.
5C is an oil passage of a retainer 26 which is rotatably supported by the sleeve 18a of the vane pump 18 via a bearing 23 and rotatably fitted into the boss portion 18b of the vane pump 18 via a plurality of seal members 24 and 25. 26a, and the retainer 26 connects the seal member 2 to the cylinder 15.
It is fixed via 7.

The oil passage 26a of the retainer 26 is connected to a solenoid valve housing portion 18f fixed to the boss portion 18b of the vane pump 18.
It communicates with an oil gear lary 18d connected to the oil discharge port 18c of the vane pump 18 via a solenoid valve (not shown) housed in the vane pump, and the oil discharged from the vane pump is controlled by the solenoid valve to the boss portion. The oil is supplied under high pressure from a high-pressure side oil gear lary 18g formed in the retainer 26 through a communication hole 26d formed in the retainer 26. Note that the end of the oil passage 15c is sealed by a steel ball 15e.

Further, an oil passage 15f is formed in the cylinder 15 at a circumferential position different from that of the oil passage 15C, and the oil passage is connected to a space 12a in the hydraulic device 12 through a communication hole 15.
g, and communicates with an oil passage 26c formed at a different position in the circumferential direction from the oil passage 26a, and the oil passage 26c is connected to the oil passage 26c via another electromagnetic valve (not shown). The oil discharged from the vane pump 18 is controlled by the electromagnetic valve and communicated with the oil gear lary 18d, and the oil flows from the low-pressure side oil gear lary 18h formed in the boss portion 18b through the communication hole 26e formed in the retainer 26 to the space in a low pressure state. 12a to obtain hydraulic pressure for cutting the flanch.

Further, 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 into a ring shape, and has a pressure plate 10 fixed to its side surface 16a on the side of the craft disk 11, and is slidable horizontally into the cylinder chamber 15b via a seal member I7. It is configured to press the pressure play (10) against the clutch disc 11 by moving to the left in the figure.

Note that the countershaft 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 with bolts 28, and
e is divided into three parts and connected by bolts 29, and a rotor 30 is rotatably housed inside the sleeve 18a through a bush 31. Also rotor 30
is housed within a ring 32, and the inner surface 32 of the ring
A has a plurality of radial grooves 30a formed in the rotor 30.
A vane 33 is slidably housed in the vane 33, and the vane 33 slides in contact with the centrifugal force caused by the rotation, so that the oil can be compressed while maintaining airtightness. Furthermore, cutouts 30b for power transmission are formed at two locations on the inner circumferential surface of the rotor 30, and the ends 26b of the retainer 26 engage with the cutouts, so that power is transmitted from the retainer to the rotor 30. ing.

The center of the ring 32 and the rotation center of the rotor 30 are eccentric by a predetermined amount of eccentricity, and this amount of eccentricity is variable. That is, on the side of the main body 18a of the vane pump 18, there is a compression spring 3 for pressure setting that presses and biases the ring pressing pin 47.
4 is housed in a cover 36 fixed to the main body with bolts 35, and the compression spring 34 is compressed by the ring 32, thereby reducing eccentricity. Further, a stopper 37 is fixed to the inner peripheral surface 32a of the ring 32,
The vertical position of the ring 32 is set by the stopper.

Next, the shape memory alloy compression spring 5 which forms the main part of the present invention
To explain the configuration of the valve device 54 using 2,
As shown in FIG. 3, the pulp device is mounted at three locations at equal intervals in the circumferential direction of the piston 16, and is completely housed in a recess 16c formed in a side surface 16b of the piston 16 on the transmission side. side 1
6b, and as shown in FIG. 5, it consists of a valve body 50, a compression spring 52 for bias, and a compression spring 53 made of a shape memory alloy.

The valve body 50 is configured to slide in the direction of the crankshaft 6 so that its tip 50a blocks the communication hole 15c and limits the stroke of the piston 16. The valve body 50 is hollow and has a cylindrical portion 50b and Flange portion 5 formed at one end
0c, a valve part 50d formed at the tip 50a, and a hole 50e for accommodating the shape memory alloy compression spring 53, and the diameter of the valve part 50d is formed larger than the diameter of the communication hole 15d. When is pressed against the communication hole 15d, the communication hole is blocked by the tip 50a.

The bias compression spring 52 is configured to press and bias the valve body 50 toward the piston 16, and is a normal metal spring that is not a shape memory alloy.
b, one end 52a abuts the flange 50c of the valve body 50, and the other end 52b abuts the lid member 55, which is formed into a substantially diamond shape with the same shape as the recess 16c, and is inserted into the recess 16c. is housed in. And the spring constant is
The compression force is weaker than the return force of the shape memory alloy compression spring 53 to the memorized state (stretched state), and when the shape memory alloy compression spring 53 returns to the secondary permanently deformed state (compressed state), the shape is The value is set so that the memory alloy compression spring can be compressed.

The lid member 55 has a hole 5 into which the cylindrical portion 50b of the valve body 50 fits.
5a, each of which is fixed to the piston 16 by two screws 56, and when the lid member is attached to the piston 16, its surface 55b is flush with the side surface 16b of the piston 16.

The shape memory alloy compression spring 53 is stored in the hole 50e of the valve body 50, and is memorized so that it presses the valve body 50 toward the communication hole 15d and expands due to temperature changes. The stretched state is the memory form, and the compressed state is the secondary permanent deformation form. In other words, when the temperature exceeds a certain value, the shape memory alloy compression spring 53 returns to its memorized state and tries to expand by generating a very strong tensile force, and when the temperature falls below a certain value, it undergoes secondary permanent deformation. The force that maintains the extended state is lost so that it may return to the processed configuration.

Shape memory alloys are broadly classified into Ni-Ti alloys and CuZn-A1 alloys, but Cu-Zn-A1 alloys are Ni-
It is cheaper than Ti alloy, has the advantage of being able to quickly follow temperature changes, has low hysteresis, and has a wide transformation temperature range.N1-Ti alloy has a large shape recovery amount and is durable (thermal cycle). It is said to have a double-digit value, excellent functional properties, and high reliability. In the present invention, any of these alloys can be used for the shape memory alloy compression spring 53.

When the temperature is high, the shape memory alloy compression spring 53 returns to its memorized state, and the valve body 5o blocks the communication hole 15c and hydraulically locks the cylinder chamber 15b, thereby reducing the stroke of the piston 16, and when the temperature is low, the bias The shape memory alloy compression spring 53 is compressed by the compression spring 52, and the valve body 50 is pulled toward the piston side, thereby opening the communication hole 15c and bottoming out so as to increase the stroke of the piston 16.

Function The present invention has a tank bottom as described above, and its function will be explained below. First, the basic operation of the hydraulic pressure bonding type clutch l will be explained. When the engine rotates, the crankshaft 6, flex plate 9, hydraulic system 12
The main body 14, cylinder 15, retainer 26, and rotor 30 of the vane pump 18 rotate at the same speed, and pressurized oil is discharged from the vane pump 18.

In the state shown in FIG. 1, oil from the vane pump 18 passes through the low-pressure side oil gear gallery 18h, the oil passage 26c, the oil passage 15f, and the communication hole 15g, and is reduced in pressure by the solenoid 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 plate 1 is filled with low-pressure oil filled in the space 12a.
0 and the piston 16 are pushed rightward in the figure, the clutch disc 11 is released, and the clutch is disengaged.

Therefore, when the clutch is connected, the solenoid valve is actuated to communicate the discharge port 18c of the vane pump 18 and the oil passage 26a, and connect the high pressure side oil gear lary 18g to the communication hole 2.
High pressure oil flows into the oil passage 26a through 6d,
The high pressure oil is transferred from the oil passage 26a to the oil passage 1.
Supply to 5C. Then, oil flows into the cylinder chamber 15b through the communication hole 15b, high pressure oil pressure is generated in the cylinder chamber, and the piston 16 is moved against the pressure plate 10.
, the clutch disc 11 is pressed against the friction member 21 of the main body 14, and the clutch disc 1
1 and the clutch is connected.

In addition, by preventing the oil from the vane pump 18 from being supplied to the oil passage 15c by operating the solenoid valve, the hydraulic pressure in the cylinder chamber 15b disappears, and the pressure plate 10 and the piston 16 are moved by the low pressure hydraulic pressure in the space 12a. The clutch can be released by pushing it back toward the center right.Next, the operation of the pulp device 54 using the compression spring 52 made of shape memory alloy, which is the main part of the present invention, will be explained. In FIG. 6, when the temperature is high, the shape memory alloy compression spring 53 tries to strongly return to its memorized state, so it presses the valve body 50, and the valve portion 50d at the tip 50a of the valve body is forced into the cylinder 15. It abuts on the communication hole 15d. As a result, the communication hole 15d is blocked by the tip 50a of the valve body 50, the cylinder chamber 15b is hydraulically locked, and the piston 1
6 is restricted, the pressure plate 10 approaches the clutch disc 11, and the pressure plate 1
The gap C between 0 and the clutch disk 11 becomes smaller, and the clutch can be quickly connected and disconnected.

Furthermore, when the temperature is low, as shown in FIG. 7, the force that tends to return the shape memory alloy compression spring 53 to its memorized state disappears, so the restoring force of the bias compression spring 52 prevails, and the bias The compression spring 53 returns the shape memory alloy compression spring 53 from the expanded state to the compressed state, that is, to the secondary permanent deformation state, and the tip 50a of the valve body 50 is inserted into the communication hole 1.
5d is released, the hydraulic lock of the cylinder chamber 15b is released. As a result, the stroke of the piston 16 increases, the gap C between the pressure plate 10 and the clutch disc 11 increases, and as a result,
Even when the viscosity of the oil increases at low temperatures, clutch drag can be prevented, the clutch is completely disengaged, gears can be engaged and removed easily, and the load on actuators that use air is reduced. can do.

Further, in the present invention, since the valve device 54 consists of only three parts, the number of parts can be reduced, and since any of the parts can be mounted without protruding from the piston 16, a hydraulic pressure bonding type Since there is no need to increase the overall length of the clutch 1 and the clutch 1 can be made compact, it is easy to mount on a vehicle.

Effects As described above, the present invention has a main body fixed to the 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 housed. In a hydraulic pressure clutch equipped with a hydraulic device consisting of a cylinder having a communication hole that communicates a passage with the cylinder chamber and a hydraulic pump that supplies oil to the cylinder, the clutch slides in the direction of the crankshaft and has a communication hole at its tip. A bias compression spring that presses and biases the valve body toward the piston, and a bias compression spring that presses and biases the valve body toward the communication hole so that it expands due to temperature changes. A valve device consisting of a compression spring made of a shape memory alloy, which has been memorized, is provided inside the piston, and when the temperature is high, the compression spring made of a shape memory alloy returns to its memorized state, and the valve body blocks the communication hole. By hydraulically locking the cylinder chamber, the piston stroke is reduced, and at low temperatures, the bias compression spring compresses the shape memory alloy compression spring, pulls the stopper toward the piston, opens the communication hole, and increases the piston stroke. This configuration has the effect of preventing the clutch from dragging at low temperatures, and as a result, it is possible to easily engage and disengage gears at low temperatures. Further, the groove bottom has the effect of quickly engaging and disengaging the clutch at high temperatures. Furthermore, a valve device consisting of only three parts that limits the stroke of the piston is installed inside the piston, reducing the number of parts and reducing clutch drag at low temperatures without increasing the overall length of the clutch. This has the effect of preventing this problem and improving the on-vehicle compatibility of the clutch.

[Brief explanation of drawings]

The drawings relate to embodiments of the present invention, and FIG. 1 is a longitudinal cross-sectional view of a hydraulic compression clutch, FIG. 2 is a longitudinal cross-sectional view of a vane pump, FIG. 3 is a front view of a piston equipped with a valve device, and FIG.
The figure is a partially broken cross-sectional view of the piston showing the valve device, FIG. 5 is an exploded perspective view of the valve device, FIG. 6 is a vertical cross-sectional view of the main part showing the operating state of the valve device at high temperatures, and FIG. 7 is a low temperature FIG. 3 is a vertical cross-sectional view of a main part showing an operating state of the valve device at a time. ■ is a hydraulic pressure clutch, 6 is a crankshaft, 10 is
is a pressure plate, 12 is a hydraulic system, 15 is a cylinder, 15b is a cylinder chamber, 15c is an oil passage, 15d
16 is a communicating hole, 16 is a piston, 18 is a vane pump which is 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, 5
4 is a valve device.

Claims (1)

[Claims] It has a main body fixed to the crankshaft of the engine, a cylinder chamber fixed to the main body and in which a ring-shaped piston for pressing a pressure plate is slidably housed, and an oil passage communicating with the cylinder chamber. In a hydraulic pressure bonding type clutch equipped with a hydraulic device consisting of a cylinder having a hole and a hydraulic pump that supplies oil to the cylinder, the clutch slides in the direction of the crankshaft so that its tip blocks the communication hole and controls the stroke of the piston. a bias compression spring that presses and biases the valve body toward the piston; and a bias compression spring that presses and biases the valve body toward the communication hole and has a memory that expands due to temperature changes. A valve device comprising a compression spring made of a shape memory alloy is provided inside the piston, and when the temperature is high, the compression spring made of the shape memory alloy returns to its memorized state, so that the valve body shields the communication hole. The stroke of the piston is reduced by hydraulically locking the cylinder chamber, and when the temperature is low, the bias compression spring compresses the shape memory alloy compression spring, and the stopper is drawn toward the piston to close the communication hole. 1. A hydraulic pressure bonding type clutch, characterized in that the clutch is configured such that the stroke of the piston is increased when the piston is opened.