KR20000034652A - Actuator of hydraulic auto-tensioner for vehicle - Google Patents

Abstract

PURPOSE: An actuator of a hydraulic auto-tensioner for a vehicle is provided to suppress excessive vibration of tension pulley when controlling a tensile force of a timing belt on cold starting state, thereby improves a durability. CONSTITUTION: An actuator of a hydraulic auto-tensioner for a vehicle comprises a body(11), a sleeve(14), a plunger(15), a return spring(13) and a pressing member(16). The pressing member(16) has a rod inserting portion(16a), a fixed flange(16b) and a pressing flange(16c). The rod inserting portion(16a) encircles the outer surface of the rod(12) inserted there into. The fixed flange(16b) is fixed to a flange portion(12b) of the rod(12). The pressing flange(16c) is mounted in the sleeve(14) in order to press actuating fluid in a reserve room(14b) when the rod(12) is moving. Therefore, even on cold starting state, excessive vibration of the tension pulley is suppressed according to a smooth transfer of the actuating fluid into a high-pressure room.

Description

Actuators of Automotive Hydraulic Autotensioners

The present invention relates to an actuator of a hydraulic autotensioner for automobiles, and more particularly, to an actuator of a hydraulic autotensioner for automobiles, which is capable of suppressing excessive vibration of the tension pulley by smoothly transporting hydraulic oil to a high pressure chamber even in a cold starting state. It is about.

The belt system of the automotive engine unit is equipped with a belt pulley on each of the above devices to be linked with the rotation of the engine to operate the device such as camshaft, alternator, power steering pump, air compressor and crankshaft, and each pulley is connected to the belt. Doing.

In addition, a tensioner is provided to adjust the tension of the belt, which is typically provided with a hydraulic autotensioner composed of an actuator and a tension pulley, and the accompanying drawings in FIG. 1 schematically illustrate such an autotensioner and a timing belt system. It is a figure shown.

That is, as shown in Figure 1, the camshaft pulley (20,30) and the crankshaft pulley 60 is connected to the timing belt 70, but the idle pulley between the two camshaft pulley (20,30) Position 40 and separate idle pulley 50 between one camshaft pulley 30 and crankshaft pulley 60 so that the timing belt 70 passes idle pulleys 40 and 50. A tension pulley 10b of the auto tensioner 10 is positioned between the other camshaft pulley 20 and the crankshaft pulley 60 so that the timing belt 70 passes through the tension pulley 10b. The actuator 10a is provided below the tension pulley 10b.

On the other hand, the actuator (10a) is made of the same structure as shown in Figure 2, the body of the actuator (10a) and the cylindrical body (11) is filled with the working oil therein; A sleeve 14 formed at the top thereof with a hollow cylindrical shape in which a hole 14a is formed, and inserted into a lower side of the body 11; A hole 15a penetrated up and down is formed in the center, and the outer wall is built into the sleeve 14 so as to be slidable up and down while maintaining a slight gap 14d with the inner wall of the sleeve 14, so that the hydraulic oil The reservoir 14b is stored, and the lower side forms a high-pressure chamber 14c through which hydraulic oil flows in and receives a compressive force, while the lower end has a check ball 15b for opening and closing the hole 15a. A plunger 15 provided with a plunger spring 15d provided at a lower end of the retainer 15c to exert a tensile force; It is embedded in the body 11, the upper end is formed with a flange portion (12b) in close contact with the inner wall of the body 11 so that the working oil can be stored in the body 11, the lower end of the plunger 15 It is placed on the top of the hole (15a) formed in the center portion, a hole (12a) for communicating the hole (15a) and the reserve chamber (14b) is formed, the outer peripheral portion of the flange portion (12b) and the sleeve (14) It consists of a rod 12 is provided with a return spring 13 interposed between the upper end.

Therefore, when the crankshaft 60 is rotated by the driving of the engine, the cam shafts 20 and 30 connected to the crankshaft 60 and the timing belt 70 rotate to control the valve mechanism. When the tension of the timing belt 70 increases, the tension pulley 10b that is pushing the timing belt 70 is pushed by the tensioned timing belt 70 so that the tension of the timing belt 70 is maintained at a constant level. Accordingly, as the return spring 13 is compressed, the rod 12 of the actuator 10a retreats in the retraction direction of the tension pulley 10b, at which time the lower end of the rod 12 is plunger spring 15d. ), The plunger 15 is moved downward while the check ball 16 below the plunger 15 closes the hole 15a of the plunger 15, and the high pressure chamber (below the plunger 15) The hydraulic fluid which was in 14c) passes through the clearance 14d between the sleeve 14 and the plunger 15, and the reserve chamber ( 14b).

In addition, when the tension of the timing belt 70 decreases, the return spring 13 is stretched as the tension of the belt acting on the tension pulley 10b is alleviated, and the return spring 13 is extended. Thus, the rod 12 moves in the direction of pushing the timing belt 70 of the tension pulley 10b, whereby the plunger 15 under the rod 12 moves upward while extending the plunger spring 15d. Then, the check ball 15b opens the hole 15a of the plunger 15, so that the hydraulic oil in the reservoir chamber 14b is lower than the hole 15a of the plunger 15 and the lower end of the rod 12. Since the high pressure chamber 14c flows through the hole 12a, the hydraulic fluid absorbs vibrations when the rod 12 and the tension pulley 10b coupled thereto move.

By the way, when the vehicle stops with the tension belt increased, the rod retreats gradually, and the hydraulic fluid moves to the reserve chamber most of the time. At the start, the rod is momentarily advanced so that the high pressure chamber is filled with the hydraulic oil. In this case, due to the high viscosity of the working oil is delayed the filling time of the working oil into the high-pressure chamber, excessive vibration and noise occurs in the tension pulley for several seconds, resulting in a problem of lowering durability.

The present invention has been made to solve the problems described above, the hydraulic hydraulic tensioner for the automobile to improve the durability by suppressing excessive vibration and noise of the tension pulley by smoothly moving the hydraulic fluid to the high-pressure chamber during cold start The purpose is to provide an actuator.

Actuator of the hydraulic hydraulic tensioner for automobiles according to the present invention for achieving the above object, the sleeve is mounted in the body filled with the hydraulic fluid, the plunger is embedded in the sleeve so that the outer wall maintains a gap with the inner wall of the sleeve, Silver forms a reservoir chamber for storing the hydraulic oil, the lower side forms a high-pressure chamber through which the hydraulic oil is introduced to receive a compressive force, a hole penetrated up and down in the center of the plunger, the plunger is formed at the lower end of the plunger A check ball which opens and closes the hole when moving up and down is provided with a plunger spring for exerting a compressive or stretching force, and is provided with a rod for moving the plunger by interlocking with the tension pulley according to the tension of the timing belt. The upper end of the rod is formed with a flange portion, the lower end is in communication with the hole of the plunger In the actuator of the hydraulic auto-tensioner for automobiles which wool is formed, and a rod insertion portion that the rod is inserted surrounding the outer circumferential surface of the rod; A fixed flange fixed to the flange of the rod; Compression member made of a compression flange embedded in the sleeve is provided so as to apply a compressive force to the working oil in the reservoir chamber when the rod is moved.

1 is a view showing an autotensioner and a belt system;

2 is a cross-sectional view showing an actuator of a conventional hydraulic autotensioner,

3 is a cross-sectional view showing an actuator of the hydraulic autotensioner according to the present invention;

Figure 4 is a perspective view of the compression member of the actuator according to the present invention.

Explanation of symbols on the main parts of the drawings

11: body 12: rod

12a, 14a, 15a: Hole 12b: Flange

13: return spring 14: sleeve

14b: reserve chamber 14c: high pressure chamber

14d: gap 15: plunger

15b: Check Ball 15c: Retainer

15d: Plunger Spring 16: Compression Member

16a: rod insert 16b: fixed flange

16c: compression flange

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Figure 3 is a cross-sectional view showing the actuator of the hydraulic autotensioner according to the present invention, Figure 4 is a perspective view showing the compression member of the actuator according to the present invention, the same reference numerals are given to the same parts as in the prior art, Figure It demonstrates in parallel with 1.

As shown, the actuator according to the present invention has a sleeve 14 mounted in the body 11 filled with hydraulic oil, and its outer wall is slidable up and down while maintaining a minute gap 14d with the inner wall of the sleeve 14. The plunger 15 is embedded in the sleeve 14 so that the upper side forms a reservoir chamber 14b for storing hydraulic oil, and the lower side forms a high pressure chamber 14c for receiving hydraulic oil to receive a compressive force. A hole 15a penetrated up and down is formed in the center of the plunger 15, and when the plunger 15 moves to the reservoir chamber 14b side or the high pressure chamber 14c side at the lower end of the plunger 15, The check ball 15b for opening and closing the hole 15a is provided with a plunger spring 15d for exerting a compressive or stretching force, and interlocks with the tension pulley 10b according to the tension of the timing belt 70. The rod 12 for moving the plunger 15 to Is provided, the upper end of the rod 12, the flange portion 12b is formed, the lower end of the hydraulic hydraulic tensioner for automobile is formed with a hole (14a) in communication with the hole (15a) of the plunger 15 In the actuator, the reserve chamber when the rod 12 moves the tension pulley 10b in a direction such that the tension of the timing belt 70 is maintained at a constant level as the tension of the timing belt 70 decreases. It is characterized in that the rod 12 is provided with a compression member 16 for compressing the working oil in the 14b to be introduced into the high pressure chamber 14c.

Here, the compression member 16 is a cylindrical rod inserting portion 16a which the rod 12 is inserted to surround the outer circumferential surface of the rod, and a disc-shaped fixing flange fixed to the flange portion 12b of the rod 12. 16b and a disc-shaped compression flange 16c having a diameter smaller than the inner diameter of the sleeve 14 to apply a compressive force to the hydraulic oil in the reservoir chamber 14b when the rod 12 moves.

Referring to the operation of the actuator of the hydraulic autotensioner for automobiles according to the present invention made as described above are as follows.

When the tension of the timing belt 70 increases, as in the prior art, the return spring 13 is compressed by the flange portion 12b of the rod 12 and the rod 12 is the high pressure chamber 14c of the sleeve 14. At this time, the lower end of the rod 12 moves the plunger 15 downward while compressing the plunger spring 15d, so that the check ball 16 below the plunger 15 is plunger 15. ) Is closed, and the hydraulic fluid in the high pressure chamber 14c flows into the reservoir chamber 14b through the gap 14d between the sleeve 14 and the plunger 15.

On the other hand, when the tension of the timing belt 70 decreases, as the return spring 13 extends, the rod 12 moves toward the reservoir chamber 14b, thereby extending the plunger spring 15d. The plunger 15 under the rod 12 moves upward, and the check ball 15b opens the hole 15a of the plunger 15, so that the hydraulic oil in the reservoir chamber 14b is plunged ( 15 is introduced into the high pressure chamber 14c via the hole 15a of the lower part of the rod 12 and the lower hole 12a of the rod 12. At this time, the compression flange 16c of the compression member 16 is in the reservoir chamber 14b. Pressure is applied to the hydraulic fluid, and thus the hydraulic oil is smoothly introduced by the increase in velocity flowing into the high pressure chamber 14c through the hole 12a of the rod 12 and the hole 15a of the plunger 15. Bar, in particular, even though the viscosity of the hydraulic fluid during cold start is high, the hydraulic fluid is quickly filled into the high-pressure chamber as described above, rod 12 and the tension pulley (10b) The vibration is reduced when moving.

As described above, the actuator of the hydraulic autotensioner for automobiles according to the present invention has an effect of suppressing excessive vibration of the tension pulley by smoothly transferring the hydraulic oil to the high pressure chamber even in the cold starting state.

Claims (1)

The sleeve 14 is mounted in the body 11 filled with the hydraulic oil, and is embedded in the sleeve 14 so that the upper portion of the sleeve 14 forms a reservoir chamber 14b in which the hydraulic oil is stored and the lower portion is the hydraulic oil. Is formed to form a high pressure chamber (14c) to receive a compressive force, the center of the plunger 15 is formed with a hole 15a penetrating up and down, the plunger 15 at the lower end of the plunger 15 ) Is provided with a plunger spring (15d) for exerting a compressive or stretching force is provided with a check ball (15b) that opens and closes the hole (15a), the tension pulley (10b) according to the tension of the timing belt (70) ) Is provided with a rod 12 for swinging the plunger 15 by interlocking with each other. A flange portion 12b is formed at an upper end of the rod 12 and a hole of the plunger 15 at the lower end thereof. Hydraulic auto tensioner for automobile in which the hole 14a which communicates with 15a is formed. In the actuator of A rod inserting portion 16a inserted into the rod 12 to surround an outer circumferential surface of the rod 12; A fixed flange 16b fixed to the flange portion 12b of the rod 12; Hydraulic auto-tensioner for automobile, characterized in that the compression member (16) made of a compression flange (16c) embedded in the sleeve 14 to apply a compressive force to the hydraulic oil in the reservoir chamber (14b) when the rod 12 is moved. Actuator.