JPH04134106A - Valve on-off timing controller - Google Patents

Abstract

PURPOSE:To eliminate a shortage of lubricating oil for sliding surfaces between a timing pulley and a camshaft by forming a groove, for holding the lubricating oil with the camshaft, at the timing pulley side of these sliding surfaces between the timing pulley and the camshaft. CONSTITUTION:When the valve on-off timing of an engine is quickened, oil is fed to an oil passage 9 and piston means 3 is shifted to the right against a spring means 6, therebyrotating a camshaft 7 unified with a damper case 2 to be engaged with each helical spline for noth inner and outer circumferences of the piston means 3 relatively to a timing pulley 1, thus the valve on-off timing is quickened. In a suchlike valve on-off timing controller, plural pieces of circular grooves 13 for holding lubricating oil are formed at the side of the timing pulley 1 lying between the camshaft 7 and the timing pulley 1. With this constitution, lubricating oil is feedable to both sliding surfaces between the timing pulley 1 and the camshaft 7 from the lubricating oil holding groove 13 at all times, thus a shortage of lubricating oil on the said sliding surface is eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a valve timing control device, and is used, for example, in general valve operating devices of internal combustion engines.

(Prior Art) As a prior art related to the present invention, there is, for example, the one described in Japanese Patent Application No. 1-61820 filed by the present applicant.

FIG. 2 shows a sectional view of a conventional valve timing control device 100.

Camshaft 120 is rotatably supported by engine body 110. An oil passage 130 is provided inside the camshaft 120. Camshaft 120 (
(left side in the figure) A timing pulley 160 is fitted on the outer periphery, and the outer periphery of the timing pulley 160 is fitted with the groove 16.
It has 0a. Further, a damper case 150 is disposed at the left end of the camshaft 120 in the figure via a knock pin 140 so as to cover the timing boot 60. The damper case 150 and the timing boot 60 are engaged through respective labyrinth grooves 150a and 160b, thereby forming a viscous damper means having a viscous fluid therein.

A cover 180 is disposed on the left side of the damper case 150 so as to cover the viscous damper means, and the outer peripheral portion of the cover 180 engages with a part of the timing boot 60.

Further, the viscous fluid sealed in the viscous damper means is transferred to an oil seal 190 disposed between the cover 180 and the damper case 150, and an oil seal 190 disposed between the cover 180 and the timing boot 1.
An O-ring 200 disposed between the damper case 150 and the timing pulley 160 prevents the oil from flowing out.

Inner circumference of damper case 150 and timing boot January 6
A piston means 220 having a cylindrical groove 220a is disposed between the outer periphery of the camshaft contact portion 160c and the outer circumferential portion of the camshaft contact portion 160c. A spring 230 is provided to do this.

A helical spline 150b is formed on the inner circumference of the damper case 150, and a helical spline 220b is formed on the outer circumference of the piston means 220 so as to mesh with the helical spline 150b. Further, a helical spline 220c is formed on the inner circumference of the piston means 220, and a helical spline 160d is formed on the inner circumference of the cam shirt 1 to the contact portion 160c of the timing pulley 160 so as to mesh with the helical spline 220c.

A hydraulic chamber 240 is formed by the inner circumference of the damper case 150, the top of the piston means 220, and the inner circumference of the camshaft contact portion 160C of the timing pulley 160. This hydraulic chamber 240 communicates with the oil passage 130 within the cam shirt l-120.

From the left side of the damper case 150, the link 250
The bolt 260 is screwed into the cam shirt +120 to prevent the damper case 150 and the like from coming off the camshaft 120.

In the above configuration, when the engine starts and the crankshaft (not shown) rotates, the rotation is transmitted to the timing pulley 160. During normal running, rotations 1 to 1 are controlled by the timing pulley 160, the helical spline 160d of the timing boot 60, the helical spline 220c220b of the piston means 220, and the damper case 1.
50 helical spline 150b, damper case 1
50, knock pin 140, and cam shirt +120.

If it is desired to advance the valve opening/closing timing of the engine (not shown) from this normal running state, oil is supplied to the oil passage 130 to expand the volume of the hydraulic chamber 240. That is, the piston means 220 overcomes the urging force of the spring means 230 to the left in the drawing and moves to the right in the drawing. Then, the helical splines 220b on the inner and outer peripheries of the piston means 220
, 220c and the helical spline 150b of the damper case 150 and the timing pulley 160, respectively.
Due to the helical spline 160d, the camshaft 120, which is integrated with the damper case 150, rotates relative to the timing pulley 160, thereby advancing the valve opening/closing timing of the engine (not shown).

Further, if it is desired to return the valve opening/closing timing of the engine (not shown) from this state, the supply of oil to the oil passage 130 is stopped and the volume of the hydraulic chamber 240 is reduced. That is, the piston means 220 moves to the left in the drawing due to the urging force of the spring means 230 to the left in the drawing. Then, the helical splines 220 on the inner and outer peripheries of the screws 1 to 220
b, a damper case 150 that engages with 220c, respectively;
Helical spline 150b and timing boot January 6th
The camshaft 120 integrated with the damper case 150 rotates relative to the timing pulley 160 by the zero helical spline 160d, thereby returning the valve opening/closing timing of the engine (not shown).

In this way, the valve opening/closing timing can be continuously controlled by the amount of oil supplied to the hydraulic chamber 240.

The camshaft 120 also receives varying torque from a spring that engages with a valve (not shown) during engine operation.

This fluctuating torque is transmitted to the helical splines 150b, 220b, 220c, 16 via the damper case 150.
0d, and each helical spline 150b, 2
The pack lashes 20b, 220e, and 160d generate a striking sound, and the negative component of this fluctuating torque tends to move the piston means 220 to the right in the figure. Then, the labyrinth groove 150a formed in the damper case 150 that is integrated with the cam shirt l-120 and the labyrinth groove 160b formed in the timing pulley 160 rotate relative to each other, so that the viscous fluid (for example, (silicone oil) acts on a large shearing force and can absorb fluctuating torque.

(Problem to be Solved by the Invention) By the way, in the above-mentioned prior art, when it is desired to advance the timing of opening and closing the valves of the engine, when hydraulic pressure is supplied to the hydraulic chamber 24 through the oil passage 130, the piston means returns. It moves to the right in the figure against the spring, thereby rotating relative to the camshaft or timing pulley via the helical spline, making it possible to advance the opening and closing timing of the engine's valves. However, at this time, if sufficient lubricating oil is not supplied to the sliding surface 160C between the timing pulley and the camshaft, frictional heat is generated, which may cause various problems. Also, if you try to increase the conversion angle of the timing pulley and increase the stroke of the axial moving part of the piston, you will need to increase the width of the timing pulley accordingly. There was a problem that the surface area became larger and lubrication deteriorated.

Therefore, in the present invention, in order to improve the lubrication of the sliding surface between the timing pulley and the camshaft, a groove for holding lubricating oil is formed on the timing pulley side of the sliding surface. The technical measures taken to solve the above-mentioned technical problems are to retain lubricating oil between the timing pulley and the camshaft on the timing pulley side of the sliding part between the timing pulley and the camshaft provided in the valve timing control device. This is due to the formation of grooves.

(Function) A groove for holding the lubricating oil between the timing pulley and the camshaft is formed on the timing pulley side of the sliding part between the timing pulley and the camshaft, so the lubricating oil is held in this holding groove. . As a result, various problems caused by lack of lubricating oil can be resolved.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings. FIG. 1 is a sectional view of the valve timing control device of the present invention.

In Fig. 1, 1 is a timing pulley, 2 is a damper case, 3 is a piston means, 4 is a knock pin, 5 is a fixing bolt, 6 is a return spring, 7 is a camshaft,
8 is a labyrinth groove, 9 is an oil passage, 11 is a hydraulic chamber,
Reference numeral 12 denotes a sealing member, which constitutes a valve timing control device having a structure similar to a conventional valve timing control device. The overall structure and operation of the valve timing control device are the same as those of the conventional valve timing control device described above, so a detailed explanation thereof will be omitted here.

In Figure 1, the damper case 2 has a dowel pin 4 and a bolt 5.
The timing pulley 1 is fitted onto the camshaft 7 so as to be slidable on the camshaft 7. Piston means 3 are fitted between the timing pulley 1 and the damper case 2 via helical splines, respectively, and the valve opening/closing timing is controlled by these. A plurality of circumferential grooves 13 for holding lubricating oil are formed on the timing pulley side between the camshaft and the timing pulley.

In the valve timing control device having the above configuration, when hydraulic pressure is supplied to the hydraulic chamber 11 through the oil passage 9 in order to advance the timing of opening and closing the valves of the engine, the piston means is moved to the right in the figure by this hydraulic pressure. At this time, the oil in the hydraulic chamber 11 enters the gap between the timing pulley 1 and the camshaft 7, and this oil collects in the lubricating oil retaining groove 13 formed in the timing pulley. For this reason, lubricating oil is always supplied to the sliding surface between the timing pulley and camshaft from the lubricating oil holding groove, so there is no chance of the sliding surface between the timing pulley and camshaft running out of lubricant. .

〔Effect of the invention〕

According to the present invention, oil that has entered the gap between the timing pulley and the camshaft from the hydraulic chamber 11 accumulates in the lubricating oil retaining groove formed in the timing pulley, so that the oil enters the gap between the timing pulley and the camshaft. Lubricating oil is always supplied from the lubricating oil retaining groove, which prevents the sliding surface of the timing pulley and camshaft from running out of lubricating oil.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a valve timing control device according to an embodiment of the present invention, and FIG. 2 is a sectional view of a conventional valve timing control device. Explanation of the main parts of the diagram 1 - Timing pulley 2 Damper case 3 - Screw 1 fixing means 4 Dowel pin 5 - Fixing pin L -
6 Return splinter 7-Camshaft 8-Labyrinth groove 9-Oil passage 11 Hydraulic chamber 12
- Seal member 13 Lubricating oil retaining groove 20
Vacant patent applicant Aisin Seiki Co., Ltd., Figure 1

Claims (1)

[Claims] A valve timing control device characterized in that a groove for retaining lubricating oil with the camshaft is formed on the timing pulley side of the sliding part between the timing pulley and the camshaft provided in the valve timing control device. .