JPH0882205A - Valve timing adjuster for internal combustion engine - Google Patents

Abstract

PURPOSE: To realize the valve timing adjuster of a compact internal combustion engine excellent in its vehicle mounting capability. CONSTITUTION: A controlling member 9 is axially moved, so that a cam shaft side member including a cam shaft 1 and a cam shaft sleeve 4 may be rotated relative to a crankshaft side member including a timing pulley 5, a sprocket sleeve 7 and a flange member. At one end of the crankshaft side member, the outer side face 7g of the inner cylindrical part 7b of the sprocket sleeve 7 is supported by the inner side face 4b of the cam shaft sleeve 4. At the other end, the inner wall face 8c of the cylindrical part 8b of a flange member 8 is supported by the outer wall face 1c of the cam shaft 1. Since the length c of the supported part at one part of the crankshaft side member overlaps the stroke range b of the controlling member 9, the device can be made compact while the distance a between the supported parts is increased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve timing adjusting device for changing the opening / closing timing of intake / exhaust valves of an internal combustion engine in accordance with operating conditions.

[0002]

2. Description of the Related Art As a valve timing adjusting device for an internal combustion engine, a cylindrical gear type control member composed of an arc gear and a piston having a helical spline on at least one of inner and outer circumferences is driven by hydraulic pressure or spring force. By doing so, the crank shaft side member and the cam shaft side member are relatively rotated. At this time, the crankshaft side member and the camshaft side member usually rotate integrally, and when the control member is moved in the axial direction, the relative rotation angle of both members can be changed so that the crankshaft side member can rotate. The member is supported by the camshaft side member.

[0003]

At this time, if the inclination of the crankshaft side member with respect to the camshaft side member is large, problems such as abnormal wear of the timing belt transmitting rotational torque from the crankshaft and increased vibration of the engine will occur. Occurs. Therefore, by supporting the crankshaft side member on the camshaft side member by one end and the other end of the crankshaft side member, the axial distance between the supported portions of the crankshaft side member is possible. It is effective to make it as large as possible so that the inclination of the crankshaft side member becomes small.

For example, in the example shown in FIG. 5, the camshaft side member is the camshaft 101 and the camshaft 101.
The crankshaft side member is composed of a timing pulley 105, a sprocket sleeve 107 assembled to the timing pulley 105, and a flange member 108. At one end of the crankshaft side member, one end 107b of the sprocket sleeve 107 is connected to the camshaft sleeve 1.
It is supported by the outer peripheral surface 104b at one end of 04.
At the other end of the crankshaft side member, the inner surface 108c of the cylindrical portion 108b of the flange member 108 is supported by the outer peripheral surface 101c of the camshaft 101. As a result, the distance a between the supported portions between one end and the other end of the crankshaft side member is increased.

However, when the stroke range b required for the control member 109 and the lengths c and d of the supported portions at one end and the other end of the crankshaft side member are arranged in the axial direction as described above. However, there is a problem that the device becomes large in size by the lengths c and d of the supported portion. It is an object of the present invention to provide a valve timing adjusting device for an internal combustion engine, which has a small distance between the supported parts of the crankshaft side member and is improved in vehicle mountability.

[0006]

In order to solve the above problems, a valve timing adjusting device according to claim 1 of the present invention is a cam for driving at least one of an intake valve and an exhaust valve of an internal combustion engine. A camshaft-side member that is fixed to the camshaft and that rotates integrally with the camshaft, a camshaft-side member that rotates in synchronization with the crankshaft of the internal combustion engine, and the cam At least one of the teeth provided on the inner and outer circumferences that meshes with the shaft-side member and the crankshaft-side member is a helical tooth, and the crankshaft-side member and the cam are moved by moving in the axial direction. A control member for relatively rotating the shaft-side member,
In the valve timing adjusting apparatus for an internal combustion engine, the crankshaft side member is supported by the camshaft side member at supported portions provided at one end and the other end, and the crankshaft side member is supported by the camshaft side member. At least one of the portions is arranged so as to overlap the stroke range of the control member in the axial direction of the cam shaft.

A valve timing adjusting device for an internal combustion engine according to a second aspect of the present invention is the valve timing adjusting device according to the first aspect, wherein the crankshaft side member is
A sprocket sleeve having an outer cylinder extending in the axial direction of the cam shaft, an inner cylinder formed at one end of the outer cylinder extending inside the outer cylinder, and a cylindrical portion extending in the axial direction of the cam shaft. A flange member having an annular portion formed at one end of the cylindrical portion and extending outward from the cylindrical portion,
The outer surface of the inner cylinder of the sprocket sleeve is supported by the inner wall surface of the rotation transmitting member at one end of the crankshaft side member.

A valve timing adjusting device for an internal combustion engine according to a third aspect of the present invention is the valve timing adjusting device according to the first or second aspect, wherein the crankshaft side member is in the axial direction of the camshaft. Sprocket sleeve having an outer cylinder extending to the outer cylinder and an inner cylinder formed at one end of the outer cylinder and extending inside the outer cylinder, a cylindrical portion extending in the axial direction of the cam shaft, and one of the cylindrical portions. A flange member having an annular portion formed at an end portion of the cylinder portion and extending outward from the cylindrical portion, and a cylinder of the flange member on the outer side surface of the cam shaft at the other end portion of the crankshaft side member. The inner surface of the part is supported.

A valve timing adjusting device for an internal combustion engine according to a fourth aspect of the present invention is the valve timing adjusting device according to the first or second aspect, wherein the crankshaft side member is in the axial direction of the camshaft. Sprocket sleeve having an outer cylinder extending to the outer cylinder and an inner cylinder formed at one end of the outer cylinder and extending inside the outer cylinder, a cylindrical portion extending in the axial direction of the cam shaft, and one of the cylindrical portions. A flange member having an annular portion that is formed at the end of the cylindrical portion and extends outward from the cylindrical portion, and at the other end of the crankshaft side member, the flange member is provided on the inner wall surface of the rotation transmitting member. The outer surface of the cylindrical portion is supported.

[0010]

According to the valve timing adjusting device for an internal combustion engine of the present invention, the crankshaft side member is supported by the camshaft side member at two locations, one end and the other end of the crankshaft side member. Therefore, the axial distance between the support portions can be increased to reduce the inclination of the crankshaft side member with respect to the camshaft side member, preventing abnormal wear of the timing belt and increasing the vibration of the engine. It has the effect of preventing it.

Since at least one of the supported parts of the crankshaft side member overlaps the stroke range of the control member, it is possible to secure a sufficient span between the supporting parts and downsize the device. can do.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) FIGS. 1 to 3 show a valve timing adjusting device for an internal combustion engine according to a first embodiment of the present invention. In the first embodiment of the present invention, the rotational torque from the crankshaft (not shown) is transmitted to the timing pulley 5 by the timing belt (not shown).

As shown in FIG. 1, a cylindrical camshaft sleeve 4 is fixed to one end of the camshaft 1 by bolts 2 and pins 3 so as to rotate integrally with the camshaft 1. An external tooth helical spline 4 a is formed on a part of the outer peripheral wall of the camshaft sleeve 4. The sprocket sleeve 7, which is a crankshaft side member, includes an outer cylinder having a small diameter portion 7d and a large diameter portion 7e,
An annular flange portion 7c extending radially outward from the anti-small diameter portion side of the large diameter portion 7e, an inner cylinder 7b, and an outer cylinder and an inner cylinder 7b extending radially inward from the anti-large diameter portion side of the small diameter portion 7d. An annular portion 7f that connects the two is integrally formed. Internal tooth helical splines 7a are formed on a part of the inner peripheral wall of the small diameter portion 7d. The internal tooth helical spline 7 a is formed to have a twist angle in the opposite direction to the external tooth helical spline 4 a of the camshaft sleeve 4. The external tooth helical spline 4 and the internal tooth helical spline 7a
Either one of them may have a twist angle of zero, and may be a linear spline parallel to the axial direction.

Flange member 8 which is a crankshaft side member
Is formed of an annular portion 8a extending in the radial direction of the camshaft 1 and a cylindrical portion 8b extending in the axial direction of the camshaft 1 toward the rear end side of the camshaft 1. The annular portion 8a of the flange member 8 and the flange portion 7c of the sprocket sleeve 7 are attached to the timing pulley 5 with bolts 6. The outer surface 7g of the inner cylindrical portion 7b of the sprocket sleeve 7 is supported by the inner surface 4b of the camshaft sleeve 4 at one end of the crankshaft side member, and the timing pulley 5 is provided at the other end of the crankshaft side member. The inner surface 8c of the cylindrical portion 8b of the camshaft flange member 8 is supported by the outer surface 1c of the camshaft 1, so that the timing pulley 5 is supported by the camshaft 1 so as to be relatively rotatable.

A control member 9 for relatively rotating the timing pulley 5 and the camshaft 1 is provided between the camshaft sleeve 4 and the sprocket sleeve 7.
By alternately assembling the two arc-shaped gears 10 and the two arc-shaped gears 14 to the piston portion 13 of the control member 9 shown in FIG. 2, one cylindrical gear is apparently formed. The upper ends of the arc gears 10, 14 have arc grooves 10e,
An annular groove is formed by 14e, and the retainer ring 12 is housed in this annular groove. The arc gears 10, 14 pass through the retainer ring 12 and the through hole 10
The pistons 13 are alternately assembled by the pins 11 inserted in d and 14d. The pin 11 is press-fitted and fixed to the piston portion 13, and a slight clearance is provided between the pin 11 and the arc gears 10 and 14 in the axial direction and the rotational direction in order to absorb an error during assembly. Internal tooth helical splines 10a and 14a are formed on the inner peripheral walls of the arc gears 10 and 14, respectively, and external tooth helical splines 10b and 14b are formed on the outer peripheral walls.

Two spring holders 14c are formed on both sides of the through hole 14d of the arc gear 14 in the rotational direction, and a spring 15 is housed in the spring holder 14c below the retainer ring 12. The axial movement of the arc gear 14 is possible within the compression range of the spring 15. Due to the elastic force of the spring 15 whose one end is supported by the retainer ring 12, the arc gear 14 is pressed toward the piston 13.

The internal tooth helical splines 10a, 14a of the arc gears 10, 14 are fitted to the external tooth helical splines 4a of the camshaft sleeve 4, and the external tooth helical splines 10b, 14b are attached to the internal tooth helical splines 7a of the sprocket sleeve 7. Mate with. At this time, the arc gear 1
4 is fitted in the arc gear 10 by a slight distance shift in the axial direction and the radial direction of the camshaft 1 by the amount of absorbing the backlash. That is, the arc gear 10 and the arc gear 14
Are subjected to the elastic force of the spring 15 in mutually opposite directions with respect to the axial direction of the camshaft 1. Due to this elastic force, a torque for rotating the camshaft 1 relative to the timing pulley 5 in the retard direction by the arc gear 10 and a torque for rotating the camshaft 1 in the advance direction with respect to the timing pulley 5 by the arc gear 14 is applied. give. Therefore, each of the arcuate gears 10, 14 positively moves the camshaft 1,
Negative fluctuating torque can be absorbed, and rattle noise between backlashes is suppressed.

Due to the engagement between the splines, the rotation of the timing pulley 5 is transmitted to the camshaft 1 via the sprocket sleeve 7, the control member 9 and the camshaft sleeve 4.

Between the camshaft sleeve 4 and the sprocket sleeve 7, a piston ring 18 fitted in a groove 13b of the piston 13 and a sliding portion 13a of the piston 13 are provided.
An advance-side hydraulic chamber 19 and a retard-side hydraulic chamber 20 which are partitioned by and are formed. The advance side hydraulic chamber 19 and the retard side hydraulic chamber 20 are liquid-sealed by the O-ring 24 of the bolt 23 and the O-ring 25 of the flange member 8 and are substantially liquid-sealed by the cylindrical portion 8b of the flange member 8. The oil seal 26 prevents the hydraulic oil leaking from the cylindrical portion 8b from leaking to the outside of the device.

By switching control of the control valve 17 by the control signal of the control device 16, the flow of the control oil to the oil passage leading to the advance side hydraulic chamber 19 and the retard side hydraulic chamber 20 is controlled. Specifically, the oil passage 4c formed in the camshaft sleeve 4 communicating with the advance side hydraulic chamber 19, the oil passage 2a formed in the bolt 2, and the oil passage 1 formed in the camshaft 1.
By connecting or disconnecting a with the oil pump 21 and the drain 22, the hydraulic pressure in the advance-side hydraulic chamber 19 is controlled. Further, the oil passage 4d formed in the camshaft sleeve 4 communicating with the retard side hydraulic chamber 20 and the oil passage 1b formed in the camshaft are connected to or cut off from the oil pump 21 and the drain 22, so that the retard side hydraulic pressure is increased. The hydraulic pressure in the chamber 20 is controlled. The control member 9 is moved or stopped in the axial direction depending on the balance between the hydraulic pressures of the advance side hydraulic chamber 19 and the retard side hydraulic chamber 20.

Compared with the advance side hydraulic chamber 19, the retard side hydraulic chamber 2
When the hydraulic pressure of 0 is increased, the control member 9 moves in the arrow P direction shown in FIG. At this time, due to the twisting action of the helical spline, a force in the rotational direction acts on the internal tooth helical spline 7a of the sprocket sleeve 7 and a rotational direction acts on the external tooth helical spline 4a of the camshaft sleeve 4 as shown in FIG. A reverse (positive torque) force acts. Therefore, the timing pulley 5 and the camshaft 1 relatively rotate in a direction in which the rotation phase of the camshaft 1 lags behind the rotation phase of the timing pulley 5 (retard angle direction).

On the other hand, when the hydraulic pressure in the advance side hydraulic chamber 19 is made higher than that in the retard side hydraulic chamber 20, the control member 9 moves in the direction of arrow Q shown in FIG. At this time, as shown in FIG. 3, a force opposite to the rotational direction acts on the internal tooth helical spline 7a of the sprocket sleeve 7, and the rotational direction (negative torque) acts on the external tooth helical spline 4a of the camshaft sleeve 4. Force of. Therefore, the timing pulley 5 and the camshaft 1 relatively rotate in a direction (advancing direction) in which the rotational phase of the camshaft 1 advances with respect to the rotational phase of the timing pulley 5.

According to the first embodiment of the present invention, the outer surface 7g of the inner cylindrical portion 7b of the sprocket sleeve 7 is supported by the inner surface 4b of the camshaft sleeve 4 at one end of the crankshaft side member, By supporting the inner surface 8c of the cylindrical portion 8b of the flange portion 8 on the outer peripheral surface 1c of the camshaft 1 at the other end of the side member, the distance a between the supported portions of the crankshaft side member increases and The inclination of the timing pulley 5 with respect to the gap between the portion and the supported portion can be reduced to prevent abnormal wear of the timing belt and increase in engine vibration.

Further, with respect to the axial direction of the camshaft 1,
Since the length c of the supported portion at one end of the crankshaft side member overlaps with the stroke range b of the control member 9, while securing a sufficient distance a between the supported portions. The device can be downsized. Further, at one end of the crankshaft side member, the crankshaft side member is supported by the inner side surface 4b of the camshaft sleeve 4, so that the entire arcuate gears 10 and 14 of the control member 9 within the stroke range. It is possible to form the helical spline 4b on the outer surface of the camshaft 4 over the entire length, and it is possible to ensure stable operation of the control member 9.

(Second Embodiment) A second embodiment of the present invention is shown in FIG.
Shown in The second embodiment is an example in which torque is transmitted from the crankshaft by a chain. The flange member 208 is formed of an annular portion 208a extending in the radial direction of the camshaft 1 and a cylindrical portion 208b extending in the axial direction of the camshaft 1 toward the sprocket sleeve 7 side.

The rotational torque from the crankshaft is changed by the chain (not shown) by the chain sprocket 205.
Is transmitted to The chain sprocket 205 includes the annular portion 208a of the flange 208 and the sprocket sleeve 7
The flange portion 7c is assembled by the bolt 6. Similar to the first embodiment, the outer surface 7g of the inner cylinder 7b of the sprocket sleeve 7 has a cylindrical camshaft sleeve 4.
It is supported by the inner side surface 4b at one end. On the other hand, the other end of the camshaft sleeve 204 has a wide inner diameter, and the cylindrical portion 208b is slidably fitted between the inner side surface 204a of the other end and the outer wall surface 1c of the camshaft 1. Has been done. As a result, the inner surface 208c of the cylindrical portion 208b of the flange member 208 is supported by the outer surface 1c of the camshaft 1, or the outer surface 208d of the cylindrical portion 208b is supported by the inner surface 204a of the other end of the camshaft sleeve 4. Supported by.

The structure of the other parts is the same as that of the first embodiment. According to the second embodiment of the present invention, the length c of the supported portion at one end of the crankshaft side member with respect to the axial direction of the camshaft 1 overlaps the stroke range of the control member 9, and Since a part of the length d of the supported portion at the other end also overlaps the stroke range b of the control member 9, a sufficient distance between the supported portions is obtained as in the first embodiment. The device can be downsized while ensuring a.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a valve timing adjusting device for an internal combustion engine according to a first embodiment of the present invention.

FIG. 2A is a plan view showing a control member of the first embodiment of the present invention, and FIG. 2B is a cross-sectional view taken along the line B-O-B of FIG.
(C) is the COC sectional view taken on the line.

FIG. 3 is an explanatory diagram showing the operation of the valve timing adjusting device for an internal combustion engine according to the first embodiment of the present invention.

FIG. 4 is a vertical sectional view showing a valve timing adjusting device for an internal combustion engine according to a second embodiment of the present invention.

FIG. 5 is a vertical cross-sectional view showing an example of a conventional valve timing adjustment device for an internal combustion engine.

[Explanation of symbols]

 1 camshaft (camshaft) 4 camshaft sleeve (rotation transmitting member) 4a external tooth helical spline 5 timing pulley (crankshaft side member) 7 sprocket sleeve (crankshaft side member) 7a internal tooth helical spline 7b internal cylinder 7g external surface 8 Flange member (crank shaft side member) 8b Cylindrical part 9 Controlling member 10, 14 Arc gear 10a, 14a Internal tooth helical spline 10b, 14b External tooth helical spline 11 Pin 12 Retainer ring 13 Piston part 14c Spring holder 15 Spring 19 Hydraulic chamber 20 Hydraulic chamber 21 Oil pump 22 Drain 204 Camshaft sleeve 205 Chain sprocket 208 Flange member

Claims (4)

[Claims] 1. A camshaft for driving at least one of an intake valve and an exhaust valve of an internal combustion engine,
A cam shaft side member that is fixed to the cam shaft and includes a rotation transmission member that rotates integrally with the cam shaft; a crank shaft side member that rotates in synchronization with a crank shaft of an internal combustion engine; and a cam shaft side member Between the crankshaft side member and the crankshaft side member, at least one of the teeth provided on the inner and outer circumferences is a bevel tooth, and the crankshaft side member and the camshaft side member are moved by moving in the axial direction. A valve timing adjusting device for an internal combustion engine, comprising: a control member for relatively rotating the crankshaft side member and the crankshaft side member in the supported portion provided at one end and the other end. An internal combustion engine, characterized in that it is supported by a camshaft side member, and at least one of the supported portions is arranged to overlap the stroke range of the control member in the axial direction of the camshaft. Valve timing adjustment device. 2. The sprocket sleeve, wherein the crankshaft-side member has an outer cylinder extending in the axial direction of the camshaft and an inner cylinder formed at one end of the outer cylinder and extending inside the outer cylinder. A flange member having a cylindrical portion extending in the axial direction of the cam shaft and an annular portion formed at one end of the cylindrical portion and extending outward from the cylindrical portion; The outer surface of the inner cylinder of the sprocket sleeve is supported on the inner wall surface of the rotation transmission member at one end.
A valve timing adjustment device for an internal combustion engine as described above. 3. The crankshaft-side member includes a sprocket sleeve having an outer cylinder extending in the axial direction of the camshaft, and an inner cylinder formed at one end of the outer cylinder and extending inside the outer cylinder. A flange member having a cylindrical portion extending in the axial direction of the cam shaft and an annular portion formed at one end of the cylindrical portion and extending outward from the cylindrical portion; 3. The valve timing adjusting device for an internal combustion engine according to claim 1, wherein an inner surface of the cylindrical portion of the flange member is supported on an outer surface of the cam shaft at the other end. 4. The sprocket sleeve, wherein the crankshaft-side member includes an outer cylinder extending in the axial direction of the camshaft, and an inner cylinder formed at one end of the outer cylinder and extending inside the outer cylinder. A flange member having a cylindrical portion extending in the axial direction of the cam shaft and an annular portion formed at one end of the cylindrical portion and extending outward from the cylindrical portion; 3. The valve timing adjusting device for an internal combustion engine according to claim 1, wherein the outer surface of the cylindrical portion of the flange member is supported on the inner wall surface of the rotation transmitting member at the other end.