JPH01224557A - Continuously variable transmission - Google Patents

Abstract

PURPOSE:To vary the pulley ratio according to the number of revolution independently of the load variation by forming the whole inside of a drive pulley on the drive side into a power piston chamber and transmitting the driving torque to the slide guide of a flyweight and a slide pulley by using a member in common. CONSTITUTION:When the centrifugal force of a flyweight 11 overwhelms the springy force of a governor spring 9, exceeding a certain number of revolution, the flyweight 11 shifts along a sliding guide part 6b, and a servovalve 7 shifts leftward along a power piston part 4a. Then, the communication between a control hole 70 and an engine oil feeding hole 40 is cut off, and at the same time, a drain hole 41 allows a power piston chamber 5g and a cut part 51 to communicates and the pressure acting onto a slide pulley 4 lowers, and the slide pulley 4 receives a leftward pressing force by a belt tension and shifts to the position where the drain hole 41 is closed again. Therefore, the pulley diameter on a trailing shaft side is continuously varied to a prescribed speed change ratio, and an auxiliary engine is driven at a decelerated number of revolution, for the high speed revolution on the engine side.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a continuously variable transmission, and particularly to a V-belt type continuously variable transmission incorporating a hydraulic servo mechanism.

[Conventional technology]

In automobiles, the driving force of the engine is used to drive auxiliary equipment such as fans and air conditioner compressors. In this case, from the standpoint of efficiency, the auxiliary equipment side is set to a higher predetermined rotation speed when the engine is idling, and even if the engine rotation speed increases, it is maintained at the predetermined rotation speed set during idling without proportionally increasing the engine speed. It is desirable that the speed change be controlled in such a manner that the two gears are tilted. This demand has become stronger as engines have become faster in recent years, from the viewpoint that it is more appropriate to reduce the speed of auxiliary equipment than to speed them up, as a noise countermeasure.

As a means for controlling the rotational speed of the driving shaft and the driven shaft, there is a continuously variable transmission that continuously changes the working diameter of the belt pulley.
A system has been proposed in which a hydraulic servo mechanism is used to control the position of a movable conical wheel forming one side of a pulley.

In this prior art, a fixed cylinder is provided in the axial direction of the movable conical wheel, and the piston rod of this fixed cylinder is brought into contact with the shaft end of the movable conical wheel. A duct is formed at the rod side end, and this duct is opened and closed by a sleeve via the flyweight-spring-arm of the drive shaft or the rod.

[Problem to be solved by the invention]

However, in this structure, the pulley ratio is changed so that the driving side load remains constant as the driven side load changes (
(The pulley ratio changes depending on the load on the driven side), so there was a problem that it could not be applied to drive control of auxiliary equipment, which needs to maintain a constant pulley ratio even when the load fluctuates, apart from gear shifting of motorized bicycles. .

Furthermore, in this transmission, the flyweight and piston are placed behind both fixed and movable pulleys, and the slider that controls the discharge of hydraulic pressure from a duct in the piston is connected by an arm that bypasses both pulleys. In addition, in order to make the piston counteract the strong spring force of the driven pulley, a large, dedicated fixed cylinder, pump, etc. are used externally. Therefore.

There are problems in that the mechanism becomes larger in both the axial and radial directions and the weight increases, and in this respect as well, it is unsuitable for use in continuously variable transmissions for automobiles.

The present invention was devised to solve the above-mentioned problems, and its purpose is that when the rotational speed of the drive shaft exceeds a certain level, the pulley ratio only changes according to the rotational speed regardless of load fluctuations. A servo-controlled V-belt type continuously variable transmission that can change speed and fix the driven side rotation speed at a constant level, and also achieves the above-mentioned speed change characteristics with a compact, lightweight mechanism and good controllability, and is easy to assemble. The goal is to provide equipment.

[Means to solve the problem]

In order to achieve this object, the present invention configures the entire interior of a slide pulley as one of the driving pulleys into a power piston chamber, arranges a flyweight and a servo valve in the power piston chamber, and arranges a flyweight and a servo valve in the power piston chamber. A single member is used to transmit drive torque to the dynamic guide and slide pulley.

In other words, the present invention is characterized by: a rigid pulley fixed to a drive shaft and having a guide surface formed inside; a guide holder having a lid at the rear end of a shaft that rotates integrally with the drive shaft; and the guide. The guide holder is equipped with a power piston part that movably fits into the shaft part of the holder, and a pulley part that comes into sliding contact with the guide surface of the rigid pulley and the lid part, and is always biased toward the rigid pulley by a spring. a slide pulley that forms a variable capacity power piston chamber between the slide pulley, a servo valve that is always biased toward the rigid pulley by a governor spring and controls the introduction and extraction of engine oil into the power piston chamber, and The power piston part has a flyweight that is interposed at the end of the servo valve and moves the servo valve in the axial direction according to the rotational speed of the drive shaft, and a sliding guide part of the flyweight and a torque transmission part for the slide pulley. The present invention further includes a guide member that is press-fixed to the inner surface of the lid portion of the guide holder by a spring member.

〔Example〕

Embodiments of the present invention will be described below with reference to the accompanying drawings.

Figures 1 to 4 show an embodiment of the continuously variable transmission according to the present invention. Each shows a state of balance.

1 is a drive shaft (crankshaft) 1 Although not shown in the figure, a driven shaft is arranged parallel to this drive shaft 1 and is connected to the input part of auxiliary equipment such as a fan and compressor.This driven shaft has a fixed pulley and a , a slide pulley is provided that is pressed toward the fixed pulley by a driven side spring.

3 is a rigid pulley fixed to the drive filter via a key, 4 is a slide pulley that is paired with the rigid pulley 3, and a V-belt 34 is connected between both pulleys 3.4 and the pulley on the driven shaft side. It is stretched to a specified tension.

5 is a guide holder whose tip is connected to the rigid pulley 3
It has a shaft portion 5a that is in close contact with the shaft portion 5a, and a lid portion 5C is integrally provided in the radial direction from the base C of the shaft portion 5a. The shaft portion 5a has a hollow shape, and a bolt 16 is inserted into the rear end of the shaft portion 5a, and is screwed into a screw hole formed from the end surface of the drive shaft 1 so that a driving torque acts in the screwing direction. As a result, the guide holder 5 is tightened in the axial direction and rotated together with the drive shaft 1. A rear cylinder 16a is fixed to the head of the bolt 16.

The axial direction (rigid pulley direction) is on the outer diameter side of the lid part 5c.
A first sliding guide 5d is formed which extends to an appropriate length, and holes are formed at regular intervals, for example, at intervals dividing the circumference into six equal parts, as shown in FIG. 5f
is drilled.

Note that, of course, the shaft portion 5a may be formed integrally with the bolt 16.

In the embodiment, the slide pulley 4 is a power paston portion 4a.
and a pulley portion 4b. Power paston part 4
a is slidably fitted onto the shaft portion 5a of the guide holder 5, and has an outwardly expanding portion 4a' that can be fitted to the stepped portion of the rigid pulley 3 at its end. Moreover, the pulley part 4b has an inner cylinder part 43 that is in sliding contact with the guide surface 3a provided inside the rigid pulley 3, and an outer cylinder part 44 that is in circumscribed contact with the sliding guide 5d of the guide holder 5. The distal end of 43 is bent at a right angle, and overlaps with the outwardly expanding portion 4a' with the seal ring 22 interposed therebetween. A variable capacity power piston chamber 5g is formed between the power piston portion 4a, the pulley portion 4b, and the guide holder lid portion 50.

Further, on the inner surface of the tapered portion of the pulley portion 4b, protrusions 4e for transmitting load are provided at regular intervals on the circumference. The protruding piece 4e is fixed to rotate at least integrally with the pulley part 4b, and as shown in FIG. A through hole 400 is formed at 4h.

An engine oil supply hole 40 is formed through the thickness of the power piston portion 4a, and a drain hole 41 is formed at a position displaced from this in the axial direction.

Further, a bolt 16 that fits into the shaft portion 5a of the guide holder 5 is provided with an engine oil supply path 12.
For example, a long groove 50 is formed in an annular shape on a detailed outer circumference corresponding to the groove 50 to allow the supply passage 12 and the engine oil supply hole 40 to communicate with each other even when the slide pulley 4 moves to any position.

Further, an oil discharge path 13 is formed on the outer periphery of the bolt 16, and a plurality of diagonal holes 131 passing through the boss portion of the rigid pulley 3 form a transformable drain chamber 5h formed between the slide pulley 4 and the rigid pulley 3. is familiar with The shaft portion 5a has the long groove 5 on the distal end side of the long groove 50.
A notch 51 (which may also be a thin shaft part) is formed in a relationship separated from 0, and this notch 51 allows the discharge path 13 and the drain hole 41 to communicate with each other even when the slide pulley 4 moves to any position. It has become.

Reference numeral 6 denotes a guide member, which is formed by pressing a metal disc, for example. As shown in FIGS. 2 and 3, the guide member 6 includes a flange portion 6a having an outer diameter that can be fitted into the base of the sliding guide 5d of the guide holder 5, and a sliding portion 6a that bulges out into a bowl shape from the flange portion 6a. A guide portion 6b is provided.

A plurality of claws 60 extending in the axial direction are bent at regular intervals on the flange portion 6a, and these claws 60 are attached to the lid portion 5.
It is engaged with a hole 5f formed at c, thereby receiving torque transmission.

Further, claw-shaped torque transmitting portions 61 are bent and formed at equal intervals at positions displaced from the claws 60. The torque transmitting parts 61 extend in the opposite direction to the claws 6o, and are respectively fitted into the through holes 400 of the protruding pieces 4e so as to allow only relative movement in the axial direction. A bearing element is provided in the torque transmitting portion 61 or the through hole 400 as required.

A spring member 10 is interposed between the guide member 6 and the pulley portion 4b of the slide pulley 4, and the pressing force of the spring member 10 suppresses and fixes the guide member 6 to the inner surface 5h of the lid portion. Although a leaf spring is used as the spring member 10 in the embodiments shown in FIGS. 1 and 2, a torsion spring may be used instead as shown in FIG. 4.

A cylindrical servo valve 7 is slidably fitted onto the power piston portion 4a, and a stopper ring 7a is fixed to the outer periphery near one end, and an arm-shaped external wave portion 7a is attached to the other end. It is provided. At least one control hole 7 is provided in the intermediate portion of the servo valve 7 through the wall thickness.
0 is provided. The control hole 70 is connected to the oil supply hole 4 of the power piston portion 4a in a balanced state.
The drain hole 41 is provided in such a positional relationship that communication with the power piston chamber 5g is cut off by the end of the servo valve at this time.

Reference numeral 8 denotes a centrifugal force canceling cover disposed behind the guide holder 5. This centrifugal force canceling cover 8 is provided.

It has a fitting part 8a on the outer diameter side that rotates integrally with the outer cylinder part 44 of the slide pulley 4 in oil-tight contact, and a boss 8b on the inner diameter side.
is formed, and is brought into close contact with the rear cylinder 16a by an oil seal 21 attached thereto. The inside of this centrifugal force canceling cover 8 has a notch 5 as shown in Fig. 1a.
1 is connected to the discharge passage 13 through a through hole 130 bored in the shaft portion 5a.

Reference numeral 11 denotes a flyweight for moving the servo valve 7 in the axial direction (in the direction opposite to the rigid pulley) according to the rotation speed of the drive shaft 1, and is composed of a plurality of balls, and the fly weight 11 Movement only in the radial direction is permitted by the holding claw provided at 7b.

Reference numeral 14 denotes a spring receiver disposed near the enlarged diameter portion ob of the servo valve 7, and as shown in FIG.
a, 14b are connected by a connecting part 14c in the axial direction, and the connecting part 14c is connected with leg parts 14d that branch out so as to straddle the width direction of the enlarged diameter part 7a, and each leg part 14d is connected to a guide holder. 5 is supported on the inner surface 5h of the lid portion. The sliding guide portion 6b of the guide member 6 has a mouth end 62 as shown in FIG.
is positioned at the rising portion 14a of the spring receiver 14.

The rising portion 14a and the outer wave portion 4a of the power piston 4b
A power piston spring 2° is interposed between the inner surfaces, and normally urges the slide pulley 4 toward the rigid pulley. In addition, the stopper ring 7a and the rising portion 14
By interposing the governor spring 9 between b, the servo valve 7 is always urged in the direction of the rigid pulley 3, and during rear idling, the flyweight 11 is connected to the sliding guide part 6b, the rising part 14a, and the connecting part. 14C and the expanded diameter portion 7a.

In this embodiment, the slide pulley 4 is made up of two parts, but the power piston part 4a and the external wave part 4a' may be constructed as a series of integral parts.

Furthermore, the oil supply path 12 does not necessarily have to be led from the drive shaft side, but may be led from the lid side of the guide holder 5.

[Effect of the embodiment]

Next, the operation and effect of this embodiment will be explained.

When the engine is stopped, the servo valve 7 is suppressed to the right end by the spring force of the governor spring 9, so the flyweight 11 is at the zero lift position, that is, sandwiched between the rising portion 14a and the external wave portion 7b as shown in FIG. be left in a depressed state. At the same time, the power piston portion 4a of the slide pulley 4 is pushed to the right by the two-piston spring 20, so that the slide pulley 4 is also held at the backward limit.

At this time, the oil supply hole 40 and the control hole 7o communicate with each other,
Since the drain hole 41 is closed at the end of the servo valve,
The power piston chamber 5g is filled with engine oil via the oil supply passage 12→annular groove 5o→supply hole 41→control hole 70, and the engine oil in the power piston chamber 5g does not flow out. In this state, the inner volume of the centrifugal force canceling cover 8 is kept small because the slide pulley 4 is retracted.

When the engine rotates from the above state, the torque of the drive shaft 1 is transmitted to the shaft portion 5a of the guide holder 5 and the lid portion 5G via the bolt 16. On the other hand, since the guide member 6 is engaged with the lid portion 5c via the claw 6o and is pressed against the lid portion 5C by the spring member 14, the guide member 6 also rotates together with the guide holder 5. Since the guide member 6 is engaged with the protruding piece 4e of the slide pulley 4 through the torque transmission part 61, the slide pulley 4 is connected to the drive shaft 1.
The flyweight 11 rotates synchronously with the external wave section 7 due to centrifugal force.
Press a.

When the rotation speed exceeds a certain level, the centrifugal force of the flyweight 11 overcomes the spring force of the governor spring 9.
The flyweight 11 is a sliding guide portion 6b of the guide member 6.
As a result, the servo valve 7 moves to the left along the power piston portion 4a of the slide pulley 4. By this movement of the servo valve 7, the control hole 7o and the engine oil supply hole 4o are cut off, and at the same time, the drain hole 41, which was blocked by the inner peripheral surface of the end portion, communicates with the power piston chamber 5g and the notch 51, so that the power piston chamber 5g of engine oil leaks outside.

As a result, the pressure acting on the slide pulley 4 decreases, and the slide pulley 4 receives a pushing force to the left due to the belt tension. moves to the position where it is closed again on the inner peripheral surface of the servo valve end. As a result, the pulley diameter on the driven shaft side is continuously changed to a predetermined speed ratio, and the auxiliary equipment is driven at a rotation speed that is reduced compared to the high speed rotation on the engine side.

During this speed change process, some of the oil flows out from the drain hole 41 and passes through the through hole 130 to the centrifugal force canceling cover 8.
As a result, the centrifugal force canceling cover 8 moves to the left as shown in the lower half of FIG. 1, and prevents the slide pulley 4 from moving toward the closing side (to the right) due to centrifugal force.

In this shift state, since the engine oil has stopped flowing into the power piston chamber 5g, the engine oil has stopped flowing into the power piston chamber 5g.
The oil pressure of g is in a locked state, and the resultant force of this locked oil pressure and the spring force of the power piston spring 2o,
The slide pulley 4 is held in a fixed position by the balance with the spring force of the driven side spring 2C.

In the present invention, the guide member 6 is the flyweight 11
It not only functions as a positioning and sliding guide, but also serves as a torque transmission means between the slide pulley 4 and the guide holder 5. Therefore, the number of parts can be reduced and the radial dimension can be reduced. Moreover, since the guide member 6 is pressed against the guide holder 5 by the spring member 10, the axial dimension can be shortened.
In addition, it is easy to assemble, and there is no loosening due to vibration, which is a problem with screw types, and it can be firmly prevented from floating. This allows for stable flyweight guidance and torque transmission at all times. can.

〔Effect of the invention〕

According to the present invention as described above, the auxiliary equipment is rotated at high speed when the engine speed is low, and is driven at a constant rotation speed even when the drive shaft speed is above a certain level, regardless of load fluctuations. In addition, since the pressure receiving area of the power piston can be increased, the control force can be made strong and stable, and the load transmission between the flyweight sliding guide and the slide pulley can also be stabilized. Can be done.

Furthermore, since the sliding guide of the flyweight and the torque transmission between the guide holder and slide pulley are shared by one member, the number of parts is reduced, resulting in a compact and lightweight structure, which reduces costs. Excellent effects can be obtained, such as being able to achieve better results.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing one half of an embodiment of the continuously variable transmission according to the present invention in an idling state and a high-speed balance state;
FIG. 1a is a sectional view showing a part of the guide holder in FIG. 1 with the phase shifted in the circumferential direction, FIG. 2 is an enlarged view of a part of FIG. 1, and FIG. The perspective view and FIG. 4 are partial cross-sectional views showing another embodiment of the present invention. ■...yJA moving axis, 3...rigid pulley, 3a...
...Guide surface, 4...Slide pulley, 4a...Power piston part, 4b...Pulley part, 4e...Protrusion piece, 5...Guide holder, 5a...Shaft part, 5c...・・・
Lid part, 5d...Sliding guide, 5f...Hole, 5g...
・Power piston chamber, 6... Guide member, 6b...
Sliding guide part, 7... Servo valve, 9... Governor spring, 10... Spring member, 11... Fly weight, 20... Power piston spring, 60...
...Claw, 61...Torque transmission unit Patent applicant: Diesel Kiki Co., Ltd.

Claims (1)

[Scope of Claims] A rigid pulley that is fixed to a drive shaft and has a guide surface formed inside; a guide holder that has a lid at the rear end of a shaft that rotates integrally with the drive shaft; and a shaft of the guide holder. A power piston part that is movably fitted into the rigid pulley, and a pulley part that slides on the guide surface of the rigid pulley and the lid part, and is constantly biased toward the rigid pulley by a spring, so that there is no space between the guide holder and the guide holder. A slide pulley that constitutes a variable capacity power piston chamber, and a power piston section of the slide pulley that is fitted onto the outside, is always biased toward the rigid pulley by a governor spring, and controls the introduction and withdrawal of engine oil into the power piston chamber. It has a servo valve, a fly weight that is interposed at the end of the servo valve and moves the servo valve in the axial direction according to the rotational speed of the drive shaft, and a sliding guide part of the fly weight and a torque transmission part for the slide pulley. . A continuously variable transmission comprising a guide member that is pressed and fixed to the inner surface of the lid portion of the guide holder by a spring member.