阅读说明：本技术 气门正时变更装置 (Valve timing changing device ) 是由 村坂力 于 2019-07-09 设计创作，主要内容包括：一种气门正时变更装置(2),具备：叶片转子(4)；壳体(6),其收纳叶片转子；弹簧(8),其一端部(8b)与壳体抵接并且另一端部(8c)与叶片转子抵接,并相对于壳体沿着叶片转子的周向对叶片转子施力；第一突出部(32),其在壳体上从叶片转子的轴向上的第一方向侧的端面(6a)突出,并与弹簧的一端部抵接而被弹簧施力；以及防脱部(34),其比弹簧的一端部靠向第一方向侧设置,并以限制弹簧的一端部向第一方向移动的方式从第一突出部延伸,第一突出部及防脱部与壳体一起被一体成型。(A valve timing changing device (2) is provided with: a vane rotor (4); a housing (6) that houses the vane rotor; a spring (8) having one end (8b) in contact with the housing and the other end (8c) in contact with the vane rotor, and biasing the vane rotor in the circumferential direction of the vane rotor with respect to the housing; a first protrusion (32) that protrudes from an end surface (6a) on the first direction side in the axial direction of the vane rotor on the housing, and that abuts against one end of the spring and is biased by the spring; and a retaining portion (34) that is provided closer to the first direction side than the one end portion of the spring and extends from the first protruding portion so as to restrict movement of the one end portion of the spring in the first direction, the first protruding portion and the retaining portion being integrally molded with the housing.)

1. A valve timing changing device for changing a valve timing of a reciprocating engine, comprising:

a vane rotor;

a casing that houses the vane rotor;

a spring having one end portion abutting against the housing and the other end portion abutting against the vane rotor, and urging the vane rotor against the housing in a circumferential direction of the vane rotor;

a first projecting portion that projects from an end surface on a first direction side in an axial direction of the vane rotor on the housing, and is urged by the spring in contact with the one end portion of the spring; and

a retaining portion that is provided closer to the first direction side than the one end portion of the spring and extends from the first protruding portion so as to restrict movement of the one end portion of the spring in the first direction,

the first protrusion and the retaining portion are integrally formed with the housing.

2. The valve timing changing apparatus according to claim 1, further comprising:

a power transmission member disposed on the opposite side of the spring with the blade rotor interposed therebetween, for transmitting power; and

a fastening member inserted through a fastening hole penetrating the housing in the axial direction and fastening the power transmission member and the housing,

the retaining portion is disposed within a range in which the fastening hole exists in the axial view.

3. The valve timing changing apparatus according to claim 1 or 2,

the housing includes an outer peripheral side protruding portion extending in the circumferential direction on an outer peripheral side of the spring so as to protrude from the end surface in the first direction,

the first protruding portion is configured to connect the outer peripheral side protruding portion and the retaining portion.

4. The valve timing changing apparatus according to claim 3,

the outer peripheral side protruding portion is integrally molded with the first protruding portion, the retaining portion, and the housing.

5. The valve timing changing apparatus according to any one of claims 1 to 4,

b > a is satisfied if a maximum value of a distance between a side surface of the first protruding portion and an outer peripheral surface of the housing is set to a, and a size of the first protruding portion in the circumferential direction is set to B.

6. The valve timing changing apparatus according to any one of claims 1 to 5,

in the axial view, if the width of the coming-off preventing portion overlapping the spring in the thickness direction of the spring is set to C and the thickness of the spring is set to D,

c ≧ D/2 is satisfied.

Technical Field

The present disclosure relates to a valve timing changing apparatus.

Background

Conventionally, in order to efficiently perform intake or exhaust in a reciprocating engine, a valve timing changing device that changes a valve timing (opening/closing timing of an intake valve or an exhaust valve) of the reciprocating engine is used in some cases.

Patent document 1 discloses a valve timing changing device including: a vane rotor; a casing that houses the vane rotor; and a spring that urges the vane rotor in a circumferential direction of the vane rotor with respect to the housing.

In the valve timing changing device described in patent document 1, a pin is press-fitted into and fixed to one end surface of a housing in the axial direction of a vane rotor, and the housing is biased from a spring via the pin. Further, a coming-off prevention portion for preventing the spring from coming off is provided on the tip end side of the pin.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2005-325758

Disclosure of Invention

Technical problem to be solved

In the valve timing changing apparatus described in patent document 1, the housing and the pin provided with the retaining portion are formed as separate members, and therefore the number of parts of the valve timing changing apparatus increases, and the structure of the valve timing changing apparatus becomes complicated, which leads to an increase in cost.

In view of the above circumstances, an object of at least one embodiment of the present invention is to provide a valve timing changing device capable of suppressing the spring from falling out with a small number of parts.

(II) technical scheme

(1) A valve timing changing device according to at least one embodiment of the present invention is a valve timing changing device for changing a valve timing of a reciprocating engine, including:

a vane rotor;

a casing that houses the vane rotor;

a spring having one end abutting against the housing and the other end abutting against the vane rotor, and urging the vane rotor relative to the housing in a circumferential direction of the vane rotor;

a first projecting portion that projects from an end surface on a first direction side in an axial direction of the vane rotor on the housing, and is abutted against one end portion of the spring and biased by the spring; and

a retaining portion provided closer to the first direction side than the one end portion of the spring and extending from the first protrusion portion so as to restrict movement of the one end portion of the spring in the first direction,

the first protrusion and the retaining portion are integrally formed with the housing.

(2) In some embodiments, the valve timing changing apparatus described in (1) above may further include:

a power transmission member disposed on the opposite side of the spring with the blade rotor interposed therebetween, for transmitting power; and

a first fastening member inserted through a first fastening hole axially penetrating the power transmission member and a second fastening hole axially penetrating the housing to fasten the power transmission member and the housing,

the anti-falling part is arranged in the range where the second fastening hole exists in the axial view.

(3) In some embodiments, in the valve timing changing apparatus described in the above (1) or (2),

the housing includes an outer peripheral side protruding portion extending in a circumferential direction on an outer peripheral side of the spring so as to protrude from an end surface in a first direction,

the first protruding portion is configured to connect the outer peripheral side protruding portion and the retaining portion.

(4) In some embodiments, in the valve timing changing apparatus described in the above (3),

the outer peripheral side protrusion is integrally formed with the first protrusion, the retaining portion, and the housing.

(5) In some embodiments, in the valve timing changing apparatus described in any one of (1) to (4) above,

b > a is satisfied if a maximum value of a distance between a side surface of the first protruding portion and an outer peripheral surface of the housing is set to a, and a size of the first protruding portion in the circumferential direction is set to B.

(6) In some embodiments, in the valve timing changing apparatus described in any one of (1) to (5) above,

in the axial view, if the width of the coming-off preventing portion overlapping the spring in the thickness direction of the spring is set to C, and the thickness of the spring is set to D,

c ≧ D/2 is satisfied.

(III) advantageous effects

According to at least one embodiment of the present invention, there is provided a valve timing changing device capable of suppressing the spring from falling off with a small number of parts.

Drawings

Fig. 1 is a schematic perspective view of a valve timing changing apparatus 2 according to an embodiment of the present invention.

Fig. 2 is an exploded perspective view of the valve timing changing apparatus 2 shown in fig. 1.

Fig. 3 is a front view of the valve timing changing apparatus 2 shown in fig. 1.

Fig. 4 is a cross-sectional view of the valve timing changing apparatus 2 shown in fig. 1 taken along the line a-a.

Fig. 5 is a partially enlarged view of the valve timing changing apparatus 2 shown in fig. 3.

Fig. 6 is a partially enlarged view of the valve timing changing apparatus 2 shown in fig. 3.

Detailed Description

Some embodiments of the invention are described below with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the constituent members described as the embodiments or shown in the drawings do not limit the scope of the present invention, and are merely illustrative examples.

For example, expressions indicating relative or absolute arrangements such as "in a certain direction", "along a certain direction", "parallel", "orthogonal", "central", "concentric", or "coaxial" do not only indicate an arrangement in a strict sense, but also indicate a state in which the elements are relatively displaced by an angle or distance to the extent that the same function can be obtained, or a tolerance is provided.

For example, expressions such as "identical", "equal", and "homogeneous" indicating that objects are in an equal state do not only indicate states that are strictly equal but also indicate states that are different in tolerance or degree of obtaining the same function.

For example, the expression indicating the shape such as a square shape or a cylindrical shape does not only indicate the shape such as a square shape or a cylindrical shape in a strict geometrical sense, but also indicates a shape including a concave and convex portion, a chamfered portion, and the like within a range in which the same effect can be obtained.

On the other hand, the expression "present", "having", "provided", "including", or "having" one constituent element is not an exclusive expression that excludes the presence of other constituent elements.

Fig. 1 is a schematic perspective view of a valve timing changing apparatus 2 according to an embodiment of the present invention. Fig. 2 is an exploded perspective view of the valve timing changing apparatus 2 shown in fig. 1. Fig. 3 is a front view of the valve timing changing apparatus 2 shown in fig. 1. Fig. 4 is a cross-sectional view of the valve timing changing apparatus 2 shown in fig. 1 taken along the line a-a.

The valve timing changing device 2 is a variable valve mechanism of a phase change type that changes the valve timing of a reciprocating engine (not shown) (the opening/closing timing of an intake valve or an exhaust valve of the reciprocating engine) by advancing or retarding the phase angle of a camshaft relative to a crankshaft (not shown). The valve timing changing device 2 is configured to: is coupled to a camshaft 20 (see fig. 4) that drives the intake valve or the exhaust valve, and rotates coaxially with the camshaft 20. The valve timing changing device 2 may be used for a two-wheeled vehicle, an automobile, or the like.

For example, as shown in fig. 2, the valve timing changing apparatus 2 includes: the vane rotor 4, the housing 6, the spring 8, the sprocket 10 (power transmission member), and a plurality of screws 12(12A to 12D).

Hereinafter, the axial direction of the vane rotor 4 is simply referred to as "axial direction", the radial direction of the vane rotor 4 is simply referred to as "radial direction", and the circumferential direction of the vane rotor 4 is simply referred to as "circumferential direction". Further, a first direction from the vane rotor 4 toward the housing 6 in the axial direction (a direction from the sprocket 10 toward the vane rotor 4 and the housing 6) is referred to as "forward direction" or simply as "forward", and a second direction from the housing 6 toward the vane rotor 4 in the axial direction (a direction from the housing 6 toward the vane rotor 4 and the sprocket 10) is referred to as "backward direction" or simply as "backward".

For example, as shown in fig. 2, the vane rotor 4 includes a vane rotor body 16 and a tubular member 18. The vane rotor body 16 includes a cylindrical portion 16a and a plurality of vane portions 16b provided at intervals in the circumferential direction on the outer circumferential side of the cylindrical portion 16 a. As shown in fig. 4, the vane rotor body 16 is configured to: the camshaft 20 that drives the intake valve or the exhaust valve is coupled to the camshaft via a bolt not shown, and rotates coaxially with the camshaft 20.

For example, as shown in fig. 2, the tubular member 18 includes a tubular portion 22 and an annular plate portion 24, and the plate portion 24 is disposed at the rear end of the tubular portion 22 along a plane intersecting the axial direction so as to face the front surface 17 of the tubular portion 16a of the vane rotor body 16. The cylindrical member 18 is positioned on the front surface 17 of the cylindrical portion 16a by a pin 19, and rotates integrally with the vane rotor body 16 and a camshaft 20 (see fig. 4). A groove 26 is formed in the cylindrical portion 22 in the axial direction, and the groove 26 penetrates the cylindrical portion 22 in the radial direction.

For example, as shown in fig. 2, a plurality of screws 12 fasten the sprocket 10 and the housing 6. In the illustrated exemplary embodiment, the plurality of screws 12 includes four screws 12(12A to 12D). A plurality of through holes 36(36A to 36D) that penetrate in the axial direction are formed in the sprocket 10 at intervals in the circumferential direction, and a plurality of fastening holes 38(38A to 38D) that penetrate in the axial direction are formed in the front cover portion 30 of the housing 6 at intervals in the circumferential direction. An internal thread is formed on the inner peripheral surface of each of the plurality of fastening holes 38. Each screw 12 is screwed into the corresponding through hole 36 and fastening hole 38, thereby fastening the sprocket 10 to the housing 6. That is, the screw 12A as the fastening member is screwed into the through-hole 36A and the fastening hole 38A, the screw 12B is screwed into the through-hole 36B and the fastening hole 38B, the screw 12C is screwed into the through-hole 36C and the fastening hole 38C, and the screw 12D is screwed into the through-hole 36D and the fastening hole 38D.

For example, as shown in fig. 1 and 4, the housing 6 includes a cylindrical portion 28 and an annular front cover portion 30, the cylindrical portion 28 houses the vane rotor 4 and circumferentially surrounds the vane rotor 4, and the front cover portion 30 is disposed along a plane orthogonal to the axial direction so as to cover the front sides of the plurality of vane portions 16b (see fig. 2).

In the housing 6, a front end surface 6a in the axial direction (a front end surface of the front cover portion 30) is provided with a first protruding portion 32 protruding in the forward direction from the end surface 6 a. A stopper portion 34 extending radially inward from the first projecting portion 32 is formed at the front end of the first projecting portion 32.

The first projecting portion 32 and the retaining portion 34 are integrally formed together with the housing 6 from the same material by die-casting. In other words, the cylindrical portion 28, the front cover portion 30, the first projecting portion 32, and the retaining portion 34 are integrally molded as one unbroken inseparable member.

For example, as shown in fig. 1, the spring 8 is attached to the casing 6 so as to urge the vane rotor 4 in the circumferential direction. In the illustrated exemplary embodiment, the spring 8 includes a coil portion 8a (spring portion) formed of a coil spring (coil spring) and having a coil shape. One end portion 8b of the spring 8 extends from the coil portion 8a in a direction intersecting the circumferential direction, and is caught and held in the groove 26 of the vane rotor 4. In the illustrated embodiment, the one end portion 8b of the spring 8 is bent from the inner peripheral portion of the coil portion 8a, extends radially inward in the groove 26, and abuts against one wall surface 26a of the pair of wall surfaces forming the groove 26. The wall surface 26a of the vane rotor 4 receives a biasing force from the one end 8b of the spring 8 toward one side in the circumferential direction (clockwise in an axial view from the front side). That is, the vane rotor 4 is biased to one side in the circumferential direction by the spring 8.

The other end portion 8c of the spring 8 extends from the coil portion 8a in a direction intersecting the circumferential direction, and is held by being caught on the side surface 32a of the first projecting portion 32. In this way, the first projection 32 functions as a spring hook for engaging the spring 8. In the illustrated embodiment, the other end portion 8c of the spring 8 is bent from the outer peripheral side portion of the coil portion 8a, extends in the radial direction toward the radially outer side, and abuts against the side surface 32a of the first protruding portion 32. The side surface 32a of the first projecting portion 32 receives a biasing force from the other end portion 8c of the spring 8 toward the other side in the circumferential direction (counterclockwise direction in an axial view from the front side). That is, the first protrusion 32 is urged to the other side in the circumferential direction by the spring 8.

In the valve timing changing device 2, the vane rotor 4 is relatively rotated in the direction of the biasing force of the spring 8 or in the direction opposite to the biasing force with respect to the housing 6 by the hydraulic pressure as the drive source, and the relative phase of the vane rotor 4 with respect to the housing 6 is changed. As a result, the valve timing of the reciprocating engine is changed by advancing or retarding the phase angle of the camshaft relative to the crankshaft, not shown.

For example, as shown in fig. 4, the retaining portion 34 is provided further toward the front side than the other end portion 8c of the spring 8, and extends from the first projecting portion 32 toward the radially inner side so as to restrict the movement of the other end portion 8c of the spring 8 in the forward direction. The coming-off preventing portion 34 prevents the spring 8 from coming off and coming off the housing 6 to the front side in the axial direction by restricting the other end portion 8c of the spring 8 from moving in the forward direction. In the illustrated exemplary embodiment, the retaining portion 34 is formed in a plate shape so as to protrude from the first protruding portion 32 toward the spring 8 side along a plane orthogonal to the axial direction. As shown in fig. 3, the retaining portion 34 overlaps at least a part of the spring 8 in the axial view. In addition, the retaining portion 34 is disposed within a range in which the fastening hole 38A exists in the axial view.

For example, as shown in fig. 4, the sprocket 10 is disposed on the opposite side of the spring 8 with the vane rotor 4 interposed therebetween, that is, on the rear side of the vane rotor 4. A tooth row 10a is formed on the outer peripheral surface of the sprocket 10. A roller chain, not shown, is wound around the tooth row 10a, and is used for transmitting power from a crankshaft of a reciprocating engine, not shown, and the power from the crankshaft is transmitted to the sprocket 10 via the tooth row 10 a. The relative phase of the vane rotor 4 with respect to the phase of the sprocket 10 (the phase of the housing 6) can be fixed by a lock mechanism (e.g., a lock pin) not shown.

For example, as shown in fig. 1 and 2, the housing 6 includes at least one outer peripheral side protruding portion 40 that extends in the circumferential direction on the outer peripheral side of the spring 8 so as to protrude in the forward direction from the end surface 6a of the housing 6. In the illustrated exemplary embodiment, the housing 6 includes a plurality of outer peripheral side protruding portions 40(40A to 40C) arranged at intervals in the circumferential direction. Each of the outer peripheral side protruding portions 40(40A to 40C) is formed in an arc shape in an axial view, and the thickness of the outer peripheral side protruding portion 40(40A to 40C) in the radial direction is constant at each position in the circumferential direction. The first protruding portion 32 is formed to connect the outer peripheral side protruding portion 40A of the plurality of outer peripheral side protruding portions 40(40A to 40C) and the retaining portion 34.

The outer peripheral side protruding portions 40(40A to 40C) are integrally molded from the same material as the first protruding portion 32, the retaining portion 34, and the housing 6. In other words, the outer peripheral side protruding portion 40(40A to 40C), the cylindrical portion 28, the front cover portion 30, the first protruding portion 32, and the retaining portion 34 are integrally molded as one unbroken inseparable member. The front end face 34a of the retaining portion 34, the front end face (top face) 32b of the first projecting portion 32, and the front end face (top face) 40A of the outer peripheral projecting portion 40A are formed on the same plane.

Fig. 5 is a partially enlarged view of the valve timing changing apparatus 2 shown in fig. 3.

In the illustrated exemplary embodiment, if the maximum value of the distance between the side surface 32a of the first projecting portion 32 and the outer peripheral surface 6B of the housing 6 (the outer peripheral surface of the cylindrical portion 28) is set to a, and the size of the first projecting portion 32 in the circumferential direction is set to B, the first projecting portion 32 is formed so as to satisfy B > a.

Fig. 6 is a partially enlarged view of the valve timing changing apparatus 2 shown in fig. 3.

In the illustrated exemplary embodiment, if the width of the retaining portion 34 and the spring 8 overlapping in the thickness direction of the spring 8 is set to C and the thickness of the spring 8 is set to D in the axial view, the retaining portion 34 is formed so as to satisfy C ≧ D/2.

Next, the operational effects achieved by the valve timing changing apparatus 2 will be described.

In the valve timing changing apparatus 2 described above, since the first projecting portion 32 and the retaining portion 34 are integrally molded with the housing 6, it is possible to suppress the spring 8 from coming off with a smaller number of parts and reduce the cost of the valve timing changing apparatus 2, compared to a valve timing changing apparatus in which the housing and the pin provided with the retaining portion are formed as separate members (for example, see patent document 1).

Further, compared to a valve timing changing apparatus in which the housing and the pin provided with the retaining portion are formed as separate members, the step of fitting the pin provided with the retaining portion to the housing by press-fitting or the like is not required, and the number of assembly steps of the valve timing changing apparatus can be reduced, so that the cost of the valve timing changing apparatus 2 can be reduced in this respect as well.

As shown in fig. 3, the retaining portion 34 is disposed in a range where the fastening hole 38A exists in the axial view. Therefore, the retaining portion 34 can be easily integrally molded with the first protruding portion 32 and the housing by a simple mold structure without requiring an undercut process.

As shown in fig. 1, the first projecting portion 32 is configured to: the outer peripheral side protruding portion 40A extending in the circumferential direction on the outer peripheral side of the spring 8 is connected to the retaining portion 34. Therefore, the outer peripheral side protruding portion 40A can suppress the spring 8 from interfering with surrounding members, and the rigidity of the outer peripheral side protruding portion 40A can effectively suppress the first protruding portion 32 from being deformed by the biasing force from the spring 8.

As shown in fig. 1, the outer peripheral side protruding portions 40(40A to 40C) are integrally molded together with the first protruding portion 32, the retaining portion 34, and the housing 6. Therefore, the spring 8 can be suppressed from interfering with surrounding components by the outer peripheral side protruding portion 40A with a small number of components, and deformation of the first protruding portion 32 due to the biasing force from the spring 8 can be effectively suppressed by the rigidity of the outer peripheral side protruding portion 40A.

Further, as shown in fig. 5, since the dimension B of the first projecting portion 32 in the circumferential direction is larger than the maximum value a of the distance between the side surface 32a of the first projecting portion 32 and the outer peripheral surface 6B of the housing 6, deformation of the first projecting portion 32 due to the urging force from the spring 8 in the circumferential direction can be effectively suppressed, as compared with when the dimension B is equal to or smaller than the maximum value a (for example, when the cross-sectional shape orthogonal to the axial direction of the first projecting portion 32 is circular).

Further, as shown in fig. 6, since the width C of the retaining portion 34 overlapping the spring 8 and the thickness D of the spring 8 satisfy C ≧ D/2 in the axial view, the spring 8 can be effectively prevented from being axially removed from the retaining portion 34.

The present invention is not limited to the above embodiments, and includes embodiments obtained by applying a modification to the above embodiments, and embodiments obtained by appropriately combining these embodiments.

For example, although the hydraulic pressure is exemplified as the drive source of the vane rotor 4 in the above embodiment, the drive source of the vane rotor 4 is not limited to the hydraulic pressure, and may be a motor or the like.

In the above embodiment, the coil spring is exemplified as the spring 8, but the spring is not limited to the coil spring, and may be another spring such as a torsion coil spring. When a coil spring is used as the spring 8, the coil spring may be a contact-type coil spring or a non-contact-type coil spring.

In the above embodiment, the vane rotor 4 side is coupled to the camshaft 20 and the housing 6 side is coupled to the crankshaft, but the vane rotor side may be coupled to the crankshaft and the housing 6 side may be coupled to the camshaft. That is, in the above-described embodiment, the configuration in which the rotational force of the crankshaft, not shown, transmitted to the sprocket 10 is transmitted from the vane rotor 4 to the camshaft 20 to rotate the camshaft 20 is exemplified, but in another embodiment, the rotational force of the crankshaft, not shown, transmitted to the vane rotor may be transmitted to the camshaft via the sprocket or another power transmission member to rotate the camshaft.

Description of the reference numerals

2-valve timing changing means; 4-a vane rotor; 6-a shell; 6 a-end face; 6 b-outer peripheral surface; 8-a spring; 8 b-an end portion; 8 c-the other end; 10-sprocket (power transmission part); 12A-screws (fastening means); 32-a first projection; 32 a-side; 34-a retaining part; 38A-fastening holes; 40A-outer peripheral side projection.