A VVT phaser structure

Abstract

The present invention provides a VVT phaser structure, comprising a housing, a planetary carrier (7) and a power output mechanism, wherein the housing is a hollow cavity structure, and the power output mechanism comprises a planetary gear (3), a pin shaft (5), a pin sleeve (6) and an output wheel (9), wherein a first pin hole (91) is arranged on the output wheel (9), one end of the pin shaft (5) forms a fixed connection structure with the planetary gear (3), and the other end forms a clearance fit structure with the pin sleeve (6), and a clearance fit structure is formed between the pin sleeve (6) and the first pin hole (91); when the rotation speed of the planetary carrier (7) is different from that of the housing, the planetary gear (3) performs planetary motion around the planetary carrier (7), and its rotation is transmitted to the output wheel (9) through the pin shaft (5). The present invention can not only reduce the axial size of the phaser, but also convert the sliding friction in the power transmission process into rolling friction, thereby improving the kinetic energy transmission efficiency of the phaser.

Description

Technical Field

[0001] The present invention relates to the field of VVT phaser structure design, and more particularly to a VVT phaser structure driven by an electric motor. Background Art

[0002] Traditional VVT phasers adjust the phase angle of the camshaft relative to the crankshaft through oil pressure. Although they have been maturely applied to engines, in actual operation, these traditional VVT phasers have a slow response speed, poor phase stability, and are greatly affected by oil temperature.

[0003] Existing electric VVT phasers use an electric motor as the power source and adopt a cross-slider output structure. Although they have advantages such as small geometric dimensions, however, the working form of this cross-slider output structure is sliding friction. Therefore, a large amount of heat is generated during the operation of the VVT phaser, which not only reduces the kinetic energy transfer efficiency of the phaser, but also poses high technological requirements for the contact surfaces of the cross-slider, thereby correspondingly increasing the overall cost of the VVT phaser. Summary of the Invention

[0004] The technical problem to be solved by the present invention is: in view of the problems existing in the prior art, to provide a VVT phaser structure that improves the kinetic energy transfer efficiency of the phaser.

[0005] The technical problem to be solved by the present invention is achieved by the following technical solutions: a VVT phaser structure includes a housing, a planet carrier, and a power output mechanism. The housing is a hollow cavity structure. The power output mechanism includes a planetary gear, a pin shaft, a pin sleeve, and an output wheel. A first pin hole is provided on the output wheel. One end of the pin shaft is fixedly connected to the planetary gear, and the other end of the pin shaft forms a clearance fit structure with the pin sleeve. A clearance fit structure is formed between the pin sleeve and the first pin hole. When the rotational speeds of the planet carrier and the housing are different, the planetary gear makes a planetary motion around the planet carrier, and its rotation is transmitted to the output wheel through the pin shaft.

[0006] Preferably, the pin sleeve is a cylindrical structure, and the first pin hole is a cylindrical hole. When the planetary gear makes a planetary motion around the planet carrier, the pin sleeve remains tangent to the first pin hole.

[0007] Preferably, the difference between the diameter of the first pin hole and the diameter of the pin sleeve is equal to twice the distance between the axis of the housing and the axis of the planet carrier.

[0008] Preferably, a plurality of first pin holes are provided on the output wheel and are evenly distributed around the output wheel.

[0009] Preferably, a second pin hole is provided on the planetary gear, and an interference fit structure is formed between one end of the pin shaft and the second pin hole.

[0010] Preferably, a plurality of second pin holes are provided on the planetary gear, and the second pin holes are evenly distributed around the planetary gear.

[0011] Preferably, the housing comprises a cover plate, a gear ring and a sprocket, wherein the gear ring is located between the cover plate and the sprocket, and the cover plate, the gear ring and the sprocket are fixedly connected to form a hollow cavity structure, forming an axial assembly space between the cover plate and the sprocket.

[0012] Preferably, it also includes positioning pins, and the cover plate, gear ring, and sprocket are assembled and positioned by the positioning pins.

[0013] Preferably, the ring gear is an internal gear, the planetary gear is an external gear, and an internal meshing transmission structure is formed between the ring gear and the planetary gear.

[0014] Preferably, the number of external teeth on the planetary gear is less than the number of internal teeth on the ring gear.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: by setting a pin shaft and a planetary gear fixedly connected, and setting a pin sleeve and a pin shaft to form a clearance fit structure, and a clearance fit structure is also formed between the pin sleeve and the first pin hole on the output wheel, when the rotation speed of the planetary carrier and the housing is different, the planetary gear moves around the planetary carrier, and its rotation can be transmitted to the output wheel through the pin shaft. The use of such a pin shaft and pin sleeve matching structure for power transmission is not only conducive to reducing the axial size of the phaser, but also can convert the sliding friction in the power transmission process into rolling friction, reducing the friction loss of the phaser, thereby improving the kinetic energy transmission efficiency of the phaser. Brief Description of the Figures

[0016] Figure 1 This is an exploded schematic diagram of the structure of a VVT phaser of the present invention.

[0017] Figure 2 This is a cross-sectional view of a VVT phaser structure of the present invention.

[0018] Figure 3 For Figure 2 AA view in .

[0019] Figure 4 For Figure 3 A partial enlarged view of point B in the middle.

[0020] Figure 5 For Figure 1 or Figure 2 Exploded schematic diagram of the shell structure in .

[0021] Figure 6 is Figure 5 a cross-sectional view of the shown housing.

[0022] Figure 7 is Figure 1 or Figure 2 a schematic exploded view of the structure of the power output mechanism in

[0023] Part marking names in the figure: 1 - cover plate, 2 - ring gear, 3 - planetary gear, 4 - first bearing, 5 - pin shaft, 6 - pin sleeve, 7 - planet carrier, 8 - second bearing, 9 - output wheel, 10 - sprocket, 11 - positioning pin, 12 - screw, 13 - connecting bolt, 14 - housing axis, 15 - camshaft, 16 - planet carrier axis, 17 - motor shaft, 18 - motor, 21 - internal teeth, 31 - external teeth, 32 - second pin hole, 91 - first pin hole. Detailed implementation manners

[0024] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0025] As Figure 1 , Figure 2 shown in the VVT phaser structure mainly includes a housing, a planet carrier 7, a camshaft 15 and a power output mechanism. The housing preferably adopts a hollow cavity structure as shown in Figure 5 , Figure 6 and specifically includes a cover plate 1, a ring gear 2 and a sprocket 10. The ring gear 2 is located between the cover plate 1 and the sprocket 10, and the cover plate 1, the ring gear 2 and the sprocket 10 are fixedly connected to form a hollow cavity structure, forming an axial assembly space between the cover plate 1 and the sprocket 10. Usually, the cover plate 1, the ring gear 2 and the sprocket 10 are detachably fixedly connected by a plurality of screws 12. For the convenience of the assembly operation of the housing, corresponding assembly pin holes can also be provided on the cover plate 1, the ring gear 2 and the sprocket 10 in advance, and then the cover plate 1, the ring gear 2 and the sprocket 10 are assembled and positioned by the positioning pin 11.

[0026] The specific structure of the power output mechanism is as shown in Figure 2 , Figure 7As shown, it specifically includes a planetary gear 3, a pin shaft 5, a pin sleeve 6, and an output wheel 9. The planetary gear 3 is located in the hollow cavity of the housing, and the output wheel 9 is located in the hollow cavity of the housing and is fixedly connected to the camshaft 15 through a connecting bolt 13. A first pin hole 91 is provided on the output wheel 9. One end of the pin shaft 5 is fixedly connected to the planetary gear 3, while the other end of the pin shaft 5 has a clearance fit with the pin sleeve 6, and the pin sleeve 6 has a clearance fit with the first pin hole 91, as Figure 3 , Figure 4 shown. Usually, a second pin hole 32 is provided on the planetary gear 3, and an interference fit is formed between one end of the pin shaft 5 and the second pin hole 32.

[0027] As Figure 2 shown, an eccentric structure is formed between the housing and the planet carrier 7, that is, an eccentricity d is formed between the housing axis 14 of the housing and the planet carrier axis 16 of the planet carrier 7. The planetary gear 3 and the planet carrier 7 are movably connected through a first bearing 4 to rotate relative to each other. At the same time, the planet carrier 7 and the output wheel 9 are movably connected through a second bearing 8 to rotate relative to each other. The planet carrier 7 supports the planetary gear 3 in the radial eccentric direction, and the planet carrier 7 is driven by a motor 18 through a motor shaft 17. The sprocket 10 of the housing rotates synchronously with the crankshaft through a chain. When the rotation speeds of the planet carrier 7 and the housing are different, the planetary gear 3 will perform a planetary motion around the planet carrier 7, and its self-rotation is transmitted to the output wheel 9 through the pin shaft 5, causing the output wheel 9 to rotate around the housing axis 14.

[0028] In the present invention, a clearance fit structure is formed between the pin sleeve 6 and the pin shaft 5, and a clearance fit structure is also formed between the pin sleeve 6 and the first pin hole 91 on the output wheel 9, so that the pin sleeve 6 can move within the space defined by the pin shaft 5 and the first pin hole 91. Using this pin shaft 5 and pin sleeve 6 matching structure for power transmission can not only reduce the axial dimension of the phaser, but also change the sliding friction during power transmission into rolling friction, thereby reducing the friction loss of the phaser and improving the kinetic energy transmission efficiency of the phaser. To further reduce the axial dimension of the phaser, the ring gear 2 is an internal gear, the planetary gear 3 is an external gear, and an internal meshing transmission structure is formed between the ring gear 2 and the planetary gear 3. Among them, the number of external teeth 31 on the planetary gear 3 is less than the number of internal teeth 21 on the ring gear 2.

[0029] To ensure the reliability of kinetic energy transfer of the phaser and further improve the kinetic energy transfer efficiency of the phaser, a plurality of first pin holes 91 may be provided on the output wheel 9 and are evenly distributed around the output wheel 9. Correspondingly, a plurality of second pin holes 32 are also provided on the planetary gear 3 and are evenly distributed around the planetary gear 3, so that a plurality of pin shafts 5 and matching pin sleeves 6 can be provided. In addition, the pin sleeve 6 is preferably of a cylindrical structure, and the first pin hole 91 is preferably a cylindrical hole. When the planetary gear 3 makes a planetary motion around the planet carrier 7, the pin sleeve 6 remains tangent to the first pin hole 91, as shown in Figure 3 , Figure 4 shown. Further, the difference between the diameter D2 of the first pin hole 91 and the diameter D1 of the pin sleeve 6 is equal to twice the distance d between the axis 14 of the housing and the axis 16 of the planet carrier, that is, D2 - D1 = 2d.

[0030] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. It should be noted that any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A VVT phaser structure, comprising a housing, a planet carrier (7) and a power output mechanism, wherein the housing is a hollow cavity structure, and the power output mechanism comprises a planetary gear (3) and an output wheel (9), characterized in that: It also includes a pin shaft (5) and a pin sleeve (6); a first pin hole (91) is provided on the output wheel (9); one end of the pin shaft (5) forms a fixed connection structure with the planetary gear (3); the other end of the pin shaft (5) forms a clearance fit structure with the pin sleeve (6); a clearance fit structure is formed between the pin sleeve (6) and the first pin hole (91); when the rotation speed of the planetary carrier (7) is different from that of the housing, the planetary gear (3) performs planetary motion around the planetary carrier (7), and its rotation is transmitted to the output wheel (9) through the pin shaft (5); The pin sleeve (6) is a cylindrical structure, and the first pin hole (91) is a cylindrical hole; when the planetary gear (3) performs planetary motion around the planetary carrier (7), the pin sleeve (6) remains tangent to the first pin hole (91); The difference between the diameter of the first pin hole (91) and the diameter of the pin sleeve (6) is equal to twice the distance between the housing axis (14) of the housing and the planetary carrier axis (16) of the planetary carrier (7); A plurality of first pin holes (91) are provided on the output wheel (9), and are evenly distributed around the output wheel (9).

2. A VVT phaser structure according to claim 1, characterized in that: A second pin hole (32) is provided on the planetary gear (3), and an interference fit structure is formed between one end of the pin shaft (5) and the second pin hole (32).

3. A VVT phaser structure according to claim 2, characterized in that: A plurality of second pin holes (32) are provided on the planetary gear (3), and are evenly distributed around the planetary gear (3).

4. A VVT phaser structure according to claim 1, characterized in that: The housing comprises a cover plate (1), a gear ring (2) and a sprocket (10); the gear ring (2) is located between the cover plate (1) and the sprocket (10); the cover plate (1), the gear ring (2) and the sprocket (10) are fixedly connected to form a hollow cavity structure, and an axial assembly space is formed between the cover plate (1) and the sprocket (10).

5. A VVT phaser structure according to claim 4, characterized in that: It also includes a positioning pin (11), and the cover plate (1), the gear ring (2), and the sprocket (10) are assembled and positioned by the positioning pin (11).

6. A VVT phaser structure according to claim 4, characterized in that: The ring gear (2) is an internal gear, the planetary gear (3) is an external gear, and an internal meshing transmission structure is formed between the ring gear (2) and the planetary gear (3).

7. A VVT phaser structure according to claim 6, characterized in that: The number of external teeth (31) on the planetary gear (3) is less than the number of internal teeth (21) on the ring gear (2).

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