JPH10141393A - Output rotating speed control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control an output member to finite speed regardless of rotational fluctuation of an input member. SOLUTION: This device is provided with an input member with an eccentric rotor 2a, an output member connected in a relatively rotatable state to the input member and internally provided with a plurality of bores 4b arranged equally in a radial direction and oil chambers 3a connected with the bores 4b, a cylindrical piston 7 fillingly mounted in a linearly movable state in the bore 4b and provided with a flange 7a formed at the inner end, and a shoe 6 of nearly polygonal pillar shape fitted to the eccentric rotor 2a and formed in such a way that the outer plane 6a orthogonal to the center of each bore is extended in an axial direction. An annular land 6b brought into sliding contact with the flange face 7a of the piston 7 so as to periodically communicate each bore 4b, filled with operating oil, with the oil chamber 3a by its relative phase is protrusively provided on the outer plane of the shoe 6, and a control spring for energizing the piston 7 in a centripetal direction so as to impede the outflow of high pressure oil filled in the bore 4b as long as the output member 3 does not exceed the specified rotating speed is disposed in the bore 4b. The output member can thereby be controlled to the specified rotating speed regardless of the increase of rotating speed of the input member.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission suitable for driving auxiliary equipment for a vehicle, and more particularly, to a mechanically coupled transmission between an input member and an output member. The present invention relates to an output rotation speed control device in which an output member is limited to a predetermined rotation speed even when the rotation speed rises to a predetermined rotation speed or more.

[0002]

2. Description of the Related Art Generally, in a vehicle, a rotational speed of a drive source (engine) which varies in a wide range is transmitted to an auxiliary machine such as an alternator at a predetermined speed, that is, a finite speed, in order to prevent deterioration of fuel efficiency and output. Required. To cope with this, for example, a CVT (controlling the output rotation speed by steplessly changing the pulley ratio of the input pulley) system between the drive source and the auxiliary devices functionally solves this problem. Although it is possible to meet the demand, it is hardly practical for practical use in view of the size and cost of the apparatus.

[0003]

SUMMARY OF THE INVENTION The present invention focuses on such a problem. In particular, a fixed cylinder is provided between an input member directly connected to a drive source and an output member interlockingly connected to accessories. An object of the present invention is to provide an output rotation speed control device having an extremely simple structure and excellent transmission efficiency by incorporating a radial piston pump mechanism of the type.

[0004]

According to a first aspect of the present invention, there is provided an output rotational speed control apparatus comprising: an input member having an eccentric rotor; and a plurality of input members having an eccentric rotor and rotatably coupled to the input member and equally arranged in a radial direction. An output member having a bore therein and an oil chamber connected thereto, a cylindrical piston fitted directly into the bore to form a flange at an inner end thereof, fitted to the eccentric rotor, and each bore center And a substantially polygonal column-shaped shoe having an outer plane perpendicular to the axis extending in the axial direction. The outer face of the shoe is in sliding contact with the flange surface of the piston, and is filled with hydraulic oil by its relative phase. An annular land that can periodically communicate with each bore and the oil chamber is protruded, and the piston is urged in the centrifugal direction in the bore so that the output member does not exceed a predetermined rotation speed. Prevents spill of high-pressure oil sealed in bore Control spring which is characterized in that it is arranged.

In this output rotation speed control device, a hollow portion (oil chamber) formed in the output member in cooperation with a polygonal columnar shoe.
Is configured to selectively communicate with the bore by the relative phase between the flange surface of the spring biased piston and the annular land, and both the oil chamber and the bore are filled with hydraulic oil. Therefore, when the input member directly connected to the engine is activated, each piston starts to move linearly due to the revolving motion of the shoe whose rotation is substantially restricted, but the volume is reduced as the piston moves. The oil in the bore, which tends to be compressed, is quickly compressed without escape by the sealing action of the annular land, so that the transmission torque produced by the shoe and the piston whose individual movement is sealed by the high-pressure oil is reduced by the output member. The input / output member is locked when the rotational load of the accessories connected with the input member is balanced, and the output member is rotated in synchronization with the input member.

When the rotation of the synchronously rotating input / output member exceeds a predetermined rotation speed (upper limit value) based on the fluctuating engine speed, the centrifugal force acting on each piston moves in the centripetal direction by the control spring. The piston floats up against the urging force of the above, and the high-pressure oil flows out through the play space between the piston and the annular land, causing slippage between the input and output members, that is, a rotation difference. As described above, the output member in the state where the locking relationship is released is rapidly reduced in rotation speed due to the rotation load of the auxiliary equipment, and when the rotation speed falls below a predetermined rotation speed (lower limit value), the output member is reduced with a decrease in centrifugal force. Since the piston is bent against the biasing force of the control spring and pressed against the annular land, the pressure of the oil in the bore, which is decreasing in volume at this point, is increased again, and the input / output members return to the locked state. I do. That is, regardless of the rotation fluctuation of the input member, the rotation of the output member interlocked with the accessories is always kept in a predetermined rotation speed region (finite speed).

According to a second aspect of the present invention, in the first aspect of the present invention, a bearing surface is formed in an outer region of the annular land so as to be in sliding contact with a flange surface of the piston. In this device, the bearing surface formed in the outer region of the annular land reduces the contact surface pressure of the annular land with the piston, thereby preventing its premature wear.

According to a third aspect of the present invention, in the second aspect, the flange of the piston extends along the width of the shoe, and the flange periodically communicates the bore with the oil chamber. It is characterized in that possible arc-shaped slots are provided. In this device, since the flange of the piston extends along the width, the inclination of the shoe can be effectively prevented by increasing the contact area in cooperation with the bearing surface.

According to a fourth aspect of the present invention, in the first, second or third aspect, the control spring is a non-linear spring. In this device, the compression reaction force of the spring rises non-linearly as the piston approaches the top dead center. Therefore, the inclination of the shoe can be skillfully suppressed also from such spring characteristics. The device according to claim 5 is characterized in that in the device according to claim 4, the non-linear spring is a conical coil spring.

In this device, the use of the conical coil spring eliminates the fear of frictional contact with the inner peripheral surface of the piston, so that more accurate control can be expected.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2,
Reference numeral 1 denotes a crankshaft of an engine (not shown), to which a cylindrical input member 2 is fixed by a key 11 and bolts 12. An eccentric rotor 2a substantially equivalent to a cam of a radial piston pump is formed integrally with the output member 2 as a cylindrical surface eccentric P with respect to the rotation axis. The main element is covered.

That is, the output member 3, which is rotatably fitted to the input member 2 via the bearings 13, 13, comprises a cylinder body 4 also serving as an end cover and a casing 5 for covering the cylinder body. It is connected in the axial direction by a plurality of bolts 14. The cylinder body 4, which is tightly fitted to the bottomed circular hole 5a of the casing 5 and closes the opening end thereof, is equally arranged in the circumferential direction in the bottomed circular hole 5a and has five arms 4a protruding in the axial direction. Each arm 4a has a bore 4b penetrating in the radial direction.

On the other hand, a shoe 6 is fitted to the eccentric rotor 2a via a bearing 15 so as to be relatively rotatable.
Is formed in a substantially pentagonal column shape in which an outer plane 6a orthogonal to the center of each bore 4b extends in the axial direction.
An annular land 6b is protruded from above. A hollow portion defined by the cylinder body 4 and the casing 5 constituting the output member 3 and the shoe 6 is configured as an oil chamber 3a, and high-viscosity hydraulic oil is supplied to each of the bores 4b and the oil chamber 3a. Is filled.

Each of the bores 4b has a flange 7 at its inner end.
The piston 7 is fitted between the stepped portion formed in its inner hole and the peripheral wall of the bottomed inner hole 5a. The spring is biased in the centripetal direction by the control spring 8 and is constantly pressed against the annular land 6b. As is clear from FIG. 2, the annular land 6b is in sliding contact with the flange 7a surface of the piston 7 based on the revolving motion of the shoe 6, and the bore 4b has a volume decreasing tendency.
And its relative position is determined in relation to the flange 7a (particularly the flange outer diameter) so that the bore 4b, which tends to increase in volume, communicates with the oil chamber 3a.

[0015] Figure 3 is an explanatory view showing a force relationship acts on the piston 7 of the locking state, the press pressing force F ₁ to the shoe 6 piston 7 by the hydraulic force P in the bore 4b, the piston 7 the are pulled apart and separation force F ₂ from the shoe 6 is selected width of approximately equal as annular land 6b,
Further, in a predetermined rotational speed range of the output member 3 in accordance with the regular rotation speed of the auxiliary machines, so that the centrifugal force F ₃ acting on the respective pistons 7 and the compression reaction force of the control spring 8 are balanced, pre-control spring 8, the spring constant is adjusted.

On the outer peripheral surface of a casing 5 constituting the output member 3, pulley portions 5 of different diameters each having a V-shaped groove are formed.
For example, the large-diameter pulley portion 5b is connected to an alternator, and the small-diameter pulley portion 5c is connected to auxiliary equipment (not shown) such as a power steering pump and a compressor via a V-belt. In addition, 16 and 17 are oil seals.

This embodiment is constructed as described above. When the input member 2 is driven in the direction of the arrow together with the crankshaft 1 of the engine, the intervention of the bearing 15 and the control spring 8 are performed.
Due to the abutment with each piston 7 based on the urging force, the shoe 6 whose rotation has been substantially restrained starts revolving, whereby each piston 7 also starts to move linearly. The sealing oil in the bore 4b, which tends to decrease in volume due to the movement, is quickly compressed without any escape by the sealing action of the annular land 6b, so that the shoe 6 and the piston 7 whose individual movements are sealed by the high-pressure oil. The input / output members 2 and 3 are locked when the transmission torque provided by the input / output device 3 is balanced with the rotational load of the auxiliary devices interlocked to the output member 3, and the output member 3 rotates in synchronization with the input member 2. I'm sullen.

Thereafter, when the rotation of the input / output members 2 and 3 that rotate synchronously rises above a predetermined rotation speed (upper limit value) based on the rotational speed of the piston that fluctuates, the piston 7 occupying each locking position is rotated. Since the centrifugal force acting on each of them causes the piston 7 to float against the compression reaction force of each of the opposing control springs 8, the high-pressure oil sealed in the bore 4 creates a play created between the bore 4 and the annular land 6 b. Then, the fluid flows out to the oil chamber (low pressure region) 3a, and slips between the input / output members 2 and 3, that is, a rotation difference occurs with a decrease in transmission torque.

As described above, the rotation speed of the output member 3 in the state where the locking relation is released is rapidly reduced due to the rotation load of the connected accessories, and falls below a predetermined rotation speed (lower limit value). In other words, as the centrifugal force decreases, the surface of the flange 7a of the piston 7 bends against the urging force of the control spring 8 and is pressed against the annular land 6b. The pressure is increased again, and the input / output members 2 and 3 recover the locked state and return to the above-described synchronous rotation. As described above, while the crankshaft 1 of the engine is driven at a high speed, the above operation is continuously repeated, so that the rotation of the output member 3 interlockingly connected to the accessories is always in a predetermined rotation speed range ( (Finite speed).

Although the control spring 8 is shown as a cylindrical coil spring in this embodiment, the control spring 8
When a non-linear spring is used, the compression reaction force of the spring rises non-linearly as the piston 7 approaches the top dead center, so that the shoe 6 is most likely to be tilted immediately before shifting to the locked state. Abnormal sliding contact between the piston and the piston 7 can be skillfully prevented, and if a conical coil spring is used as a non-linear spring, concerns about frictional contact with the inner peripheral surface of the piston 7 can be eliminated, so that control accuracy can be improved. It is further advantageous from the point that can be secured.

FIG. 4 shows a different embodiment of the shoe. In the present embodiment, a shoe 60 is provided in the outer region of an annular land 61 similar to that of the previous embodiment. A contact bearing surface 62 is formed. For this reason, the contact surface pressure of the annular land 61 on the surface of the flange 7a is reduced, and the progress of wear can be suppressed well.

FIG. 5 shows a different embodiment of the piston. The piston 70 of this embodiment has a flange 71 extending along the width of the shoe 60, and the flange 71 has the bore 4b. An arc-shaped long hole 72 that can periodically communicate with the oil chamber 3a is provided therethrough. Therefore, the inclination of the shoe 60 can be more effectively prevented by increasing the contact area in cooperation with the bearing surface 62.

[0023]

As described in detail above, the device of the present invention has a radial piston pump mechanism disposed between an input member and an output member, and in particular, adopts a structure in which a piston functions as a control valve. Is changed in two ways, locking and releasing, so that the output member can be maintained in a predetermined rotation speed region (finite speed) regardless of the increase in the rotation speed of the input member. The load on the drive source is reduced, and the enclosed hydraulic oil is not used for circulation as in ordinary pump work, so there is no viscosity reduction or oil leakage due to the increase in oil temperature, and extremely high power transmission Efficiency can be obtained. Further, since the mechanical energy applied to the input member is transmitted to the output member via hydraulic energy (hydraulic pressure), the rotational fluctuation shock applied to the accessories due to the damper effect is subtly reduced.

[Brief description of the drawings]

FIG. 1 is a sectional front view showing an embodiment of the device of the present invention.

FIG. 2 is a sectional side view taken along line II-II of FIG.

FIG. 3 is an explanatory diagram showing a relationship between forces acting on a piston in a locked state.

4A and 4B show different embodiments of the shoe, wherein FIG. 4A is a plan view of a main part, and FIG.

5A and 5B show different embodiments of the piston, wherein FIG. 5A is a sectional front view and FIG. 5B is a plan view.

[Explanation of symbols]

2 is an input member, 2a is an eccentric rotor, 3 is an output member, 3a
Is an oil chamber, 4b is a bore, 6 is a shoe, 6b is an annular land,
7 is a piston, 7a is a flange, 8 is a control spring.

Claims (5)

[Claims] An input member having an eccentric rotor, an output member having a plurality of bores radially equally coupled to the input member and equally arranged in a radial direction, and an oil chamber connected to the bore; A cylindrical piston which is fitted to the bore so as to be able to move directly and has a flange formed at the inner end, and a substantially polygonal column shape fitted with the eccentric rotor and having an outer plane perpendicular to the center of each bore extending in the axial direction. An annular land is provided on the outer surface of the shoe, which is in sliding contact with the flange surface of the piston and can periodically communicate the respective bores filled with hydraulic oil and the oil chamber on the outer surface of the shoe. A control spring is provided to protrude and bias the piston in a centripetal direction in the bore to prevent the high-pressure oil sealed in the bore from flowing out unless the output member exceeds a predetermined number of revolutions. Output circuit characterized by being installed Number control device. 2. The device according to claim 1, wherein a bearing surface is formed in an outer region of said annular land, which is in sliding contact with a flange surface of said piston. 3. A flange of the piston extends along a width of the shoe, and the flange is provided with an arc-shaped long hole through which the bore and the oil chamber can be periodically communicated. 3. The apparatus according to claim 2, wherein 4. The device according to claim 1, wherein the control spring is a non-linear spring. 5. The apparatus according to claim 4, wherein said non-linear spring is a conical coil spring.