JPH01145461A - Continuously variable transmission - Google Patents

Abstract

PURPOSE:To obtain a driven side speed in a fixed value by building a flywheel and its associated hydraulic servo mechanism in the inside of a drive side pulley further integrally forming a slide pulley of the drive side pulley with a power piston. CONSTITUTION:When an engine rotates, a slide pulley 4 synchronously rotates with a drive shaft 1, and a flyweight 11 generates thrust by centrifugal force, pressing a pressing piece 7a in the axial direction. Exceeding a certain fixed speed, when the centrifugal force of the flyweight 11 overcomes tension of a governor spring 9, a servo valve 7 curves along an inner cylinder part 4a of the slide pulley 4 moving in the direction of a rigid pulley 3. Thus allowing engine oil in a power piston chamber 5g to flow out causing a pressure, acting on the slide pulley 4, to decrease, the slide pulley 4 follows up to the servo valve 7, moving to a position where a drain hole 41 is closed by the internal peripheral surface in the end part of the servo valve. In this way, a pulley diameter in a driven shaft side can be continuously changed to the predetermined speed change ratio.

Description

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

[Conventional technology and its problems]

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 rotational speed when the engine is idling, and the speed of the auxiliary equipment is controlled so that the rotational speed of the auxiliary equipment does not change significantly even if the engine rotational speed changes greatly. It is hoped that 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.

In general, as a means of controlling the rotation speed of the drive shaft and driven shaft, ■
There is a continuously variable transmission that continuously changes the working diameter of a belt pulley. For example, Japanese Patent Laid-Open No. 60-26845 discloses a movable conical wheel that uses a hydraulic servo mechanism to form one side of a pulley. It has been proposed to control the position of the

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.

In this structure, the shaft of the movable conical wheel is arranged in series with the external piston rod, and the force that attempts to change the boolean ratio due to changes in the driven side load opposes the hydraulic pressure applied directly to the piston rod. Therefore, the pulley ratio is changed so that the drive side load remains constant according to changes in the driven side load (the pulley ratio changes according to the driven side load), and therefore, apart from the speed change of a motorized bicycle, the load There is a problem in that it cannot be applied to drive control of auxiliary equipment that requires maintaining a constant pulley ratio even when there are fluctuations.

Moreover, in this transmission, the flyweight and piston are arranged behind both fixed and movable pulleys, and the slider that controls the discharge of hydraulic pressure from the duct bored in the piston is connected by an arm that bypasses both pulleys. In order to counteract the strong spring force of the driven pulley of the piston, a large, dedicated external fixed cylinder, pump, etc. are required, which causes problems such as the mechanism becomes larger, heavier, and more expensive. The above-mentioned speed change characteristics between the main shaft of the engine and the auxiliary equipment have been achieved with a compact, lightweight mechanism and good controllability.

[Means for solving problems]

The present invention was developed through research in order to solve the above-mentioned problems, and its purpose is to maintain the pulley ratio so that when the rotational speed of the drive shaft exceeds a certain level, the rotational speed remains constant regardless of load fluctuations. It is an object of the present invention to provide a servo-controlled V-belt type continuously variable transmission device that can change the rotation speed only in response to the rotational speed and fix the rotation speed of the driven side at a constant value, and can also achieve a smaller and lighter mechanism. .

In order to achieve this object, the present invention incorporates a flywheel for controlling the position of the slide pulley and a hydraulic servo mechanism linked thereto inside the drive pulley. It is integrated with the power piston, making almost the entire interior a power piston chamber.
The flyweight and servo valve are placed inside the power piston chamber.

That is, the present invention includes a rigid pulley fixed to a drive shaft, a guide holder having a shaft portion that rotates integrally with the drive shaft, and a flange portion extending in the radial direction, and a guide holder having an outer peripheral side that slides on the flange portion and an inner peripheral side that slides on the rigid pulley. The slide pulley is provided with a centrifugal force canceling cover for forming a variable capacity equal pressure chamber behind the guide holder, and the slide pulley is integrally provided with a power piston that slides in contact with the shaft portion, and the flange portion is in contact with the slide pulley. The power piston is connected to the inner surface of the flange section so that it can be translated in translation via a motion transmission mechanism, and is constantly biased toward the rigid pulley by a spring interposed between the receiving member provided on the flange section and the power piston. A servo valve is fitted onto the power piston of the slide pulley to control the introduction and extraction of engine oil into the power piston chamber, and the servo valve is interposed between the stoppers. It is always biased toward the rigid pulley by the governor spring, and a flyweight is interposed between the end of the servo valve and the receiving member to move the servo valve in the axial direction according to the rotation speed of the drive shaft. It is structured as follows.

〔Example〕

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

Figures 1 and 2 show a first embodiment of the continuously variable transmission according to the present invention, and Figure 1 shows the balance state at idling.
FIG. 2 shows the balance states during high-speed operation.

1 is a drive shaft (crankshaft), 2 is a driven shaft arranged parallel to the drive shaft, and is connected to an input part of an auxiliary machine (not shown) such as a fan or a compressor. This driven shaft 2 is provided with a fixed pulley 2a and a movable pulley 2b that is pressed toward the fixed pulley 2a by a driven side spring 2c.

3 is a rigid pulley fixed to the drive shaft 1 via a key, and 4 is a slide pulley that forms a pair with the rigid pulley 3. Between these two pulleys 3.4 and the driven shaft side pulleys 2a and 2b, The V-belt 34 is stretched with a predetermined tension.

5 is a guide holder, and in this embodiment, a solid shaft portion 5 is used.
b is integrally formed, and a bolt portion 5a is integrally formed on the shaft portion 5b via a stepped portion, and a screw hole 10 is formed in the axial direction from the end surface of the drive shaft 1.

It is screwed so that the driving torque acts in the screwing direction. A radially extending flange portion 5C is integrally provided at the rear end of the shaft portion 5b, and the flange portion 5C
A rear cylinder 5f is provided to protrude in the axial direction.

A sliding guide 5d that extends to an appropriate length in the axial direction (rigid pulley direction) is formed on the outer diameter side of the flange portion 5c, and a sliding guide 5d that is located inside the sliding guide 5d constitutes one side of the motion transmission mechanism. Further, a receiving member 8 whose inner diameter side is a movement locus forming surface is fixed between the protruding piece 5e and the shaft portion 5b by any means such as press-fitting, gluing, screwing, etc. .

The shaft portion 5b does not necessarily have to be solid, but may be made hollow at the same time as in the third embodiment described later, and may be fixed using bolts so that it rotates integrally with the drive shaft.

The slide pulley 4 is integrally equipped with a power piston. In this embodiment, the power piston has an inner cylinder portion 4a that is slidably fitted onto the shaft portion 5b of the guide holder 5.
The power piston part 4b has an outer peripheral side that comes into sliding contact with a guide surface 3a provided inside the rigid pulley 3. A pulley part 4c is connected to the end of the power piston part 4b in a tapered shape and forms a groove with the rigid pulley 3. The terminal end of the pulley part 4c is connected to the sliding guide 5d of the guide holder 5. An outer cylinder part 4d is formed, and these inner cylinder part 4a, power piston part 4b,
A variable capacity power piston chamber 5g is formed between the pulley portion 4G, the outer cylinder portion 4d, and the flange portion 50. The inner surface of the power piston portion 4b and the flange portion 5c
The power piston spring 2 is inserted between the receiving member 8 fixed to the
0 is interposed, and normally urges the slide pulley 4 in the direction of the rigid pulley.

Further, on the inside of the pulley portion 4c, a protrusion 4e is provided on one side of the motion transmission mechanism, that is, a protrusion 4e that engages with the protrusion 5e of the flange portion 5c to transmit the rotational torque of the guide holder 5 to the slide pulley 4. ing. In this embodiment, one of the protruding pieces 4e and 5e forms a bifurcated groove, and the other one slides in the axial direction along this groove.

An engine oil supply hole 40 penetrating through the wall thickness is formed at an intermediate portion in the longitudinal direction of the inner cylinder portion 4a, and an engine oil supply hole 40 is formed at a position offset to the end wall by the inside of the rigid pulley 3 and the power piston portion 4b. A drain hole 41 is formed that can communicate with the drain chamber 5h. Further, an engine oil supply passage 12 and a discharge passage 13 are bored in the shaft part 5b of the guide holder 5, and a slide pulley 4 is provided on the outer periphery of the shaft part corresponding to the tips of the supply passage 12 and the discharge passage 13. An annular groove 50 for providing electrical continuity between the supply passage 12 and the engine oil supply hole 4o even when the slide pulley 4 is moved to any position;
A notch 51 is formed to conduct electricity.

Reference numeral 6 denotes a centrifugal force canceling cover arranged behind the guide holder 5. The centrifugal force canceling cover 6 has a fitting part 6a on the outer periphery that is fluid-tightly fitted with the outer cylinder part 4d of the slide pulley 4 and rotates together with the outer cylindrical part 4d, and a boss 6b is formed on the inner periphery. The oil seal 21 attached to the shaft rear cylinder 5
It is designed to be in close contact with f. The inside of the centrifugal force canceling cover 6 is connected to the discharge passage 13 through a through hole 130 formed in the shaft portion 5b.

Reference numeral 7 denotes a cylindrical servo valve that is slidably fitted onto the inner cylindrical portion 4a of the slide pulley 4, and has at least one control hole 70 bored through it in the thickness direction. In this servo valve 7, a stopper ring 7b is fixed to the outer periphery near one end, and an arm-shaped or flange-shaped push piece 7a is provided at the other end.
Since a governor spring 9 is interposed between b and the receiving member 8, the servo valve 7 is always urged in the direction of the rigid pulley 3.

In the balanced state, communication between the control hole 70 and the engine oil supply hole 4o of the inner cylinder portion 4a is cut off, and at this time, communication between the drain hole 41 and the power piston chamber 5g is cut off by the servo valve end. They are located in such a positional relationship.

Reference numeral 11 denotes a flyweight that applies thrust to the servo valve 7 according to the rotation speed of the drive shaft 1 to move it in the axial direction (anti-rigid pulley direction), and is made up of a plurality of balls (for example, 6 balls). , is interposed between the push piece 7a of the servo valve 7 and the receiving member 8.

In this embodiment, the engine oil supply path 12 is
The tip of the guide holder 5 communicates with a stationary passage assembly 14 disposed on the shaft portion 5b, and is connected to an engine oil supply system via a supply pipe 15. Further, the engine oil discharge passage 13 is bored in the bolt portion 5a, and the drive shaft 1
It is led from there to an oil pan, etc. (not shown).

FIG. 3 shows a second embodiment of the present invention. In this embodiment, engine oil is supplied from the drive shaft 1, and the engine oil is supplied from the drive shaft 1.
I'm trying to change it back to . That is, the engine oil supply path 12 is bored at the center of the shaft portion 5b and the bolt portion 5a, and the tip is closed by a blind plug 16, and at a position in front of this, a side path 17 is provided to connect the outer diameter of the drive shaft 1. guided by. Further, the engine oil discharge path 13 is connected to the side path 1.
The supply passage 12 is bored parallel to the supply passage 12 at a position displaced in the circumferential direction so as not to be connected to the supply passage 7, and is led to an oil pan or the like. The sliding surfaces on both sides of the side passage 17 are sealed by seal rings 18 and 19.

In this embodiment, the upper half is shown with the engine stopped or in an idling state, and the lower half is shown with a gear change state.The other configurations are the same as those in FIGS. 1 and 2, so they are indicated by the same reference numerals. stop.

FIG. 4 shows a third embodiment of the present invention, with the upper half showing the engine stopped or idling, and the lower half showing the gear changing state. In this embodiment, the guide holder 5
The shaft portion 5b is configured as a hollow shaft, and the mounting fitted into this is tightened and fixed to the drive shaft 1 by a bolt 5a', so that rotational torque is transmitted. A rear cylinder 5f is fitted onto the head of the bolt 5a'.

Further, in this embodiment, the power piston portion 4b and a portion on the outer diameter side thereof are made into two parts, and are integrated by a power piston spring 20 with an O-ring 22 interposed therebetween. It goes without saying that instead of this, the same configuration as in the first embodiment can be adopted.

Furthermore, in this embodiment, the receiving member 8 is a common part with the protruding piece 5e that constitutes the motion transmission mechanism. That is, the receiving member 8 is attached to the flange 8 as shown in FIG. 4a.
The flange 8a is fixed to the flange 5c of the guide holder 5 by screws or the like.

The flange 8a is formed with projecting pieces 5e cut and raised in a direction perpendicular to the flange 8a at required intervals. I am addicted to being allowed. On the other hand, the tip of the bowl-shaped portion 8b is positioned in contact with the second receiving member 80.

The second receiving member 80 has a cylindrical shape as shown in FIGS. 4 and 4a, and has one longitudinal end surface abutted against and supported by the inner surface of the flange portion of the guide holder 5, and the other end. An outward flange 80a is formed on the cylindrical portion, and inward flanges 80b are cut and raised at regular intervals in the circumferential direction, and the power piston spring 20 is supported by the outward flange 80a. The governor spring 9 is supported by the flange 80b. Therefore, in this embodiment, the push piece 7a is configured as a plurality of arms branched in the circumferential direction, and each month of the cylindrical portion passes through each arm orthogonally. Note that, of course, the second receiving member 80 may be formed integrally with the receiving member 8.

Further, in this embodiment, the engine oil drain passage 13 is formed on the outer periphery of the bolt 5a', and the drain chamber 5 is formed by a plurality of diagonal holes 131 penetrating the boss portion of the rigid pulley 3.
It communicates with h.

Since the other parts have the same structure as the second embodiment, the same reference numerals are used and detailed explanations are omitted.

The sliding portions of the protrusions 4e and 5e constituting the motion transmission mechanism may be simply plane-to-plane contact.

If the sliding resistance is large, the responsiveness of the slide pulley 4 may deteriorate when the engine speed increases and decreases. Fifth
Figures (a) and (b) and Figures 6 (a) and (b) show this countermeasure. A ball 500 is placed therein, and this ball 500 is held by a holder 502. Figures 5(b) and 6(b) show rollers 5 instead of balls.
03 was used. Ball 500 and roller 503
The number and size of the contacts are appropriately selected depending on the contact surface pressure, etc. If these structures are adopted, the relative sliding resistance between the slide pulley 4 and the guide holder 5 is reduced due to rolling contact, and the slide pulley 4 is smoothly moved in the axial direction.

In addition, in the drawing, 1. Although it corresponds to the second embodiment,
Of course, this also applies to the third embodiment.

[Effects of Examples-]

Next, take as an example what is shown in Figures 1 and 2.

Explain the operation and effects.

When the engine is stopped, the spring force of the governor spring 9 presses the servo valve 7 to the right end (backward limit), so the flyweight 11 is at the zero lift position, that is, the state where it is sandwiched between the receiving member 8 and the pushing piece 7a. It will be destroyed. At the same time, the power piston portion 4b of the slide pulley 4 is pushed to the right by the power piston spring 20, so that the slide pulley 4 is held at the backward limit. At this time, engine oil supply hole 4
0 communicates with the control hole 70, and the drain hole 41 is closed at the end of the servo valve, so the engine oil supply passage 12
The power piston chamber 5g is filled with engine oil via the annular groove 50, the supply hole 40, and the control hole 70, and the engine oil in the power piston chamber 5g does not flow out.

Since the power piston chamber 5g is formed to have a large volume inside the slide pulley 4 and the inside of the flange portion 5c of the guide holder 5, the pressure receiving area is large. Therefore, the power of the power piston chamber 5g is large, and the resultant force of the oil pressure P of the power piston chamber 5g and the spring force SP1 of the power piston spring 2o increases accordingly, even if the spring force of the power screw 1 spring 20 is reduced. Against the strong spring force SP2 of the driven side spring 2c, p+s'p□〉s
A relationship of p2 can be established. In this state,
Since the slide pulley 4 is at the backward limit, the centrifugal force canceling cover 6 approaches the flange portion 5c of the guide holder 5, and its internal volume is kept small.

When the engine rotates from the above state, the slide pulley 4 rotates in synchronization with the drive shaft 1 via the drive shaft 1 → bolt part 5 → shaft part 5b → flange part 5c → protrusion 4e, and the flyweight 11 is rotated by centrifugal force. A thrust is generated to press the push piece 7a in the axial direction. After a certain number of revolutions is exceeded, the fly weight becomes 11.
When the centrifugal force of overcomes the spring force of governor spring 9,
The servo valve 7 moves to the left (in the direction opposite to the rigid pulley) along the inner cylindrical portion 4a of the slide pulley 4. By this movement of the servo valve 7, the control hole 70 and the engine oil supply hole 40 are cut off, and at the same time, the drain hole 41 communicates the power piston chamber 5g with the notch 51, so that the engine oil in the power piston chamber 5g is drained from the power piston. The water flows out into the drain chamber 5h outside the portion 4b and into the centrifugal force canceling cover 6.

As a result, the pressure acting on the slide pulley 4 decreases, and since the spring force SP of the power piston spring 2o and the spring force SP2 of the driven side spring have a relationship of sp, < sp2, the slide pulley 4 is moved by the belt tension. In response to the leftward pressing force, the slide pulley 4 follows the servo valve 7 and moves to a position where the drain hole 41 of the inner cylinder portion 4a is closed again on the inner circumferential surface of the end of the servo valve. As a result, the diameter of the pulley on the driven shaft side is continuously changed to a predetermined speed ratio (for example, 1:0.5), 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, a portion of the engine oil flowing out from the drain hole 41 flows into the centrifugal force canceling cover 6 through the conduction hole 130. As a result, the centrifugal force canceling cover 6 is pressed toward the side opposite to the guide holder due to the internal pressure, so the slide boot IJ 4 does not move toward the closing side (rightward) due to the centrifugal force. In this shift state, as shown in Fig. 2, since the engine oil has stopped flowing into the power piston chamber 5g, the oil pressure in the power piston chamber 5g is in a locked state, and this locked oil pressure and the spring of the power piston spring 2o The slide pulley 4 is held in a fixed position by the balance between the resultant force of the force SP□ and the spring force SP2 of the driven side spring 2c. At this time, as described above, since the volume of the power piston chamber 5g is large, a stable control force can be obtained. In the third embodiment, the receiving member 8 not only functions as a sliding guide for the flyweight 11 but also serves as a torque transmitting means between the slide pulley 4 and the guide holder 5. This makes it possible to reduce the radial dimensions.

〔Effect of the invention〕

According to the present invention described above, the auxiliary equipment is rotated at high speed when the engine speed is low, and is opened and operated at a constant speed even when the drive shaft speed is above a certain level, regardless of load fluctuations. Can be done.

Moreover, since the power piston and slide pulley are integrated and the entire interior is used as the power piston chamber, the pressure receiving area of the power piston can be increased, and therefore the control force can be made strong and stable.

Furthermore, in addition to using engine oil without requiring special hydraulic oil, the power piston is integrated with the slide pulley, and the servo valve and flyweight are placed inside the power piston, making it relatively compact. The structure can be made lightweight and the number of parts can be reduced.
Excellent effects such as overall cost reduction can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a first embodiment of the continuously variable transmission according to the present invention with the engine stopped or in an idling state;
3 is a sectional view showing the second embodiment of the present invention, FIG. 4 is a sectional view showing the third embodiment of the present invention, and FIG. 4a is a sectional view showing the third embodiment. A partially enlarged perspective view of
5(a) and 5(b) are cross-sectional views showing an embodiment of the motion transmitter groove in the present invention, and FIGS. 6(a) and 6(b) are longitudinal sectional views thereof. DESCRIPTION OF SYMBOLS 1... Drive shaft, 3... Rigid pulley, 4... Slide pulley, 4a... Inner cylinder part, 4b... Power piston part, 4d... Outer cylinder part, 4e... Projection Piece 5...
・Guide holder, 5a...Bolt part, 5c...Flange part, 5d...First sliding guide, 5e...Protrusion piece, 5g...Power piston chamber, 6...Centrifugal force Offset cover, 7... Servo valve, 70... Control hole, 9
...Governor spring, 11...Fly weight,
12... Engine oil supply path, 13... Engine oil discharge path, 20... Power piston spring. Patent applicant: Diesel Equipment Co., Ltd.

Claims (1)

[Scope of Claims] (1) A rigid pulley fixed to a drive shaft, a guide holder having a shaft portion that rotates integrally with the drive shaft and a flange portion extending in the radial direction, the outer peripheral side of which is in sliding contact with the flange portion, and the inner periphery of the guide holder. A slide pulley whose side slides in contact with the rigid pulley, and a cover for canceling centrifugal force to form a variable capacity equal pressure chamber behind the guide holder, and the slide pulley is integrally equipped with a power piston that slides in contact with the shaft portion. At the same time, the inner surface of the flange is always urged toward the rigid pulley by a spring interposed between the power piston and the receiving member provided on the flange, which is connected to the flange so as to be able to move in translation via a motion transmission mechanism. A power piston chamber is configured between the slide pulley and the power piston, and a servo valve that controls the introduction and extraction of engine oil into the power piston chamber is fitted onto the power piston of the slide pulley, and the servo valve is connected to the power piston chamber. The governor spring interposed between the stoppers always biases the rigid pulley side, and between the end of the servo valve and the receiving member there is a fly weight that moves the servo valve in the axial direction according to the rotation speed of the drive shaft. A continuously variable transmission characterized in that a continuously variable transmission is provided. (2) The continuously variable transmission according to claim 1, wherein the shaft portion of the guide holder is solid and directly connected to the drive shaft. (3) The continuously variable transmission according to claim 1, wherein the shaft portion of the guide holder is hollow and receives rotational transmission from the drive shaft via a mounting bolt. (4) The continuously variable transmission according to claim 1, wherein the motion transmission mechanism between the guide holder and the slide pulley has a sliding surface in rolling contact. (5) The continuously variable transmission according to claim 1, including one in which the receiving member and the motion transmission mechanism are integrated. (6) The continuously variable transmission according to claim 1, wherein engine oil is introduced and extracted from the drive shaft side. (7) The continuously variable transmission according to claim 1, wherein engine oil is introduced from the guide holder side and extracted from the drive shaft side.