Scissors Gear and Sub-Gear

Abstract

To provide scissor gear that enables weight reduction of the main gear and, consequently, the scissor gear itself. [Solution] The scissors gear comprises a main gear rotatable around an axis and having a bearing portion that protrudes in the axial direction, a sub-gear rotatable relative to the main gear, and a biasing member having both ends, one end of which biases the main gear to one side in the rotational direction and the other end of which biases the sub-gear to the other side in the rotational direction, wherein the sub-gear has a holding portion that holds a plurality of gear teeth provided at predetermined intervals on its outer circumference, and a fitting portion that is arranged in the same axial direction as the main gear and is arranged inside the holding portion without contacting the holding portion, and is fitted and fixed to the bearing portion, and the biasing member is arranged in the space formed between the fitting portion and the holding portion, one end of which is fixed to the fitting portion and the other end is fixed to the holding portion.

Description

Technical Field

[0001] The present disclosure relates to a scissors gear and a sub-gear.

Background Art

[0002] Conventionally, a scissors gear has been known in which a substantially annular biasing member (e.g., a spring) is installed in the space between the main gear and the sub-gear, one end of which is fixed to a stopper pin (hereinafter simply referred to as a pin) of the main gear, and the other end of which is fixed to a pin of the sub-gear (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a conventional scissors gear, if the main gear is thinned or hollowed out, the strength of the gear itself decreases, making it difficult to hold the pin. Also, in the case of hollowing out, the number of locations for providing holes for connecting the pins decreases, making it difficult to provide connection points for the pins. Therefore, it has been difficult to reduce the weight of the main gear and thus the weight of the scissors gear in a conventional scissors gear.

[0005] An object of one aspect of the present disclosure is to provide a scissors gear and a sub-gear capable of reducing the weight of the main gear and thus the weight of the scissors gear.

Means for Solving the Problems

[0006] A scissors gear according to one aspect of the present disclosure comprises a main gear rotatable about an axis and having a bearing portion projecting in the axial direction, a sub-gear rotatable relative to the main gear, and a biasing member having both ends, one end of which biases the main gear to one side in the rotational direction and the other end of which biases the sub-gear to the other side in the rotational direction, wherein the sub-gear has a holding portion that holds a plurality of gear teeth provided at predetermined intervals on its outer circumference, and a fitting portion that is arranged in the same axial direction as the main gear and is arranged inside the holding portion without contacting the holding portion, and is fitted and fixed to the bearing portion, and the biasing member is arranged in the space formed between the fitting portion and the holding portion, one end of which is fixed to the fitting portion and the other end is fixed to the holding portion.

[0007] A subgear relating to one aspect of this disclosure is a subgear used in a scissor gear relating to the above aspect of this disclosure. [Effects of the Invention]

[0008] According to this disclosure, it is possible to reduce the weight of the main gear and, consequently, the scissor gear. [Brief explanation of the drawing]

[0009] [Figure 1] Exploded perspective view of a scissor gear according to an embodiment of the present disclosure. [Figure 2] Front view of a subgear according to an embodiment of the present disclosure [Figure 3] Axial cross-sectional view of a scissor gear according to an embodiment of the present disclosure [Modes for carrying out the invention]

[0010] The embodiments of this disclosure will be described below with reference to the drawings. Common components in each drawing are denoted by the same reference numerals.

[0011] The configuration of the scissors gear 100 according to this embodiment will be explained with reference to Figures 1 to 3. Figure 1 is an exploded perspective view of the scissors gear 100. Figure 2 is a front view of the subgear 2 with the spring 3 housed inside. Figure 3 is an axial cross-sectional view of the scissors gear 100. The straight line A shown in Figures 1 and 3 is the axial center line of the scissors gear 100. In the following explanation, "axis" refers to the straight line A.

[0012] The Scissors Gear 100 can be used, for example, mounted on a vehicle as a power transmission mechanism for an engine or transmission.

[0013] As shown in Figures 1 and 3, the scissors gear 100 includes a main gear 1 that is rotatable around an axis, a sub-gear 2 that is rotatable relative to the main gear 1, and a spring 3 that biases the main gear 1 in one direction of rotation and the sub-gear 2 in the other direction of rotation.

[0014] As shown in Figure 1, the main gear 1 is an annular member having a circular opening (which may also be called a through hole; no reference numeral is used) in its central portion. As shown in Figure 1, the main gear 1 holds a plurality of gear teeth 11 on its outer circumferential surface. The gear teeth 11 are arranged at predetermined intervals in the circumferential direction.

[0015] Furthermore, as shown in Figure 1, a hollow cylindrical bearing portion 12 protruding in the axial direction is provided in the central part of the main gear 1. The circular opening described above is formed in the inner circumference of the bearing portion 12. For example, a gear shaft of an engine block (not shown) is inserted into this bearing portion 12.

[0016] As shown in Figure 1, the subgear 2 has an annular retaining portion 21 and a hollow cylindrical fitting portion 22.

[0017] As shown in Figure 1, the holding portion 21 holds a plurality of gear teeth 23 on its outer circumferential surface. The gear teeth 23 are arranged at predetermined intervals in the circumferential direction.

[0018] As shown in FIG. 1, the fitting portion 22 is arranged in the same axial direction as the main gear 1. Also, as shown in FIGS. 1 and 2, the fitting portion 22 is arranged inside the holding portion 21 without contacting the holding portion 21. Further, the holding portion 21 and the fitting portion 22 are arranged with their respective axial centers aligned.

[0019] The inner diameter of the fitting portion 22 is slightly larger than the outer diameter of the bearing portion 12 of the main gear 1. Then, as shown in FIG. 3, the fitting portion 22 is fitted and fixed to the bearing portion 12 of the main gear 1, for example, by shrink fitting.

[0020] As shown in FIGS. 1 and 2, an accommodating portion 24, which is an annular space, is formed between the holding portion 21 and the fitting portion 22. As shown in FIG. 2, the spring 3 is accommodated in this accommodating portion 24. Details thereof will be described later.

[0021] As shown in FIG. 1, the spring 3 is a biasing member having a shape of the letter "C" (which may be referred to as a substantially annular shape) and has end portions 31, 32 (an example of both end portions). Note that the shapes of the end portions 31 and 32 are not limited to the illustrations in FIGS. 1 and 2. Also, the shapes of the end portions 31 and 32 may be different from each other as shown in FIGS. 1 and 2, or may be the same.

[0022] As shown in FIG. 2, the spring 3 is arranged in the accommodating portion 24 of the sub-gear 2. As shown in FIG. 2, the end portion 32 is fixed by contacting the outer peripheral surface of the fitting portion 22, and the end portion 31 is fixed by contacting the inner peripheral surface of the holding portion 21. In this way, the holding portion 21 and the fitting portion 22 are connected via the spring 3. Thereby, it becomes possible for the end portion 32 to bias the main gear 1 in one rotational direction and for the end portion 31 to bias the sub-gear 2 in the other rotational direction.

[0023] As a method of fixing the end part 31 to the holding part 21 and fixing the end part 32 to the fitting part 22, for example, welding can be mentioned, but it is not limited thereto. For example, a known pin (a stopper pin that has been conventionally provided on a main gear or a sub gear) can be provided on each of the inner peripheral surface of the holding part 21 and the outer peripheral surface of the fitting part 22, and the end parts 31 and 32 can be connected to those pins. In this case, a known spring (a spring having both ends for pin connection) can also be applied. Or, for example, the holding part 21, the fitting part 22, and the spring 3 in the state shown in FIG. 2 may be integrally molded.

[0024] As shown in FIG. 3, the sub gear 2 housing the spring 3 is assembled to the main gear 1 by fitting the fitting part 22 into the bearing part 12 of the main gear 1. In FIG. 3, the illustration of the spring 3 is omitted.

[0025] Also, although illustration is omitted, the scissors gear 100 in the state shown in FIG. 3 is attached to, for example, the gear shaft of an engine block. Specifically, a gear shaft with a bush is inserted into the bearing part 12 from the main gear 1 side, a flange is attached to the sub gear 2 side so as to cover the gear shaft and each gear, and bolts are inserted into the bolt holes of the gear shaft from the flange side. Also, since the operation of the scissors gear 100 is the same as that of a conventional scissors gear, the description here is omitted.

[0026] As described above, the scissors gear 100 of this embodiment is a scissors gear comprising a main gear 1 that is rotatable around an axis and has a bearing portion 12 that protrudes in the axial direction, a sub-gear 2 that is rotatable relative to the main gear 1, and a spring 3 as an example of a biasing member having ends 31 and 32, the end 32 of which biases the main gear 1 to one side in the rotational direction, and the end 31 of which biases the sub-gear 2 to the other side in the rotational direction, wherein the sub-gear 2 has a holding portion 21 that holds a plurality of gear teeth 23 provided at predetermined intervals on its outer circumference, and a fitting portion 22 that is arranged in the same axial direction as the main gear 1 and is arranged inside the holding portion 21 without contacting the holding portion 21, and is fitted and fixed to the bearing portion 12, and the spring 3 is arranged in a housing portion 24 which is a space formed between the fitting portion 22 and the holding portion, and of the ends 31 and 32 of the spring 3, the end 32 is fixed to the fitting portion 22 and the end 31 is fixed to the holding portion 21.

[0027] Therefore, in the scissors gear 100 of this embodiment, since there is no need to provide a pin in the main gear 1, the main gear 1 can be made thinner or lighter, thereby achieving a reduction in the weight of the main gear 1. Furthermore, by using this main gear 1, a reduction in the weight of the scissors gear can be achieved.

[0028] Furthermore, in the scissors gear 100 of this embodiment, a configuration without pins on the main gear 1 and sub-gear 2 can be selected (for example, welding or integral molding as described above), in which case the number of parts and manufacturing man-hours in the scissors gear 100 can be reduced.

[0029] Furthermore, in the scissors gear 100 of this embodiment, the weight reduction of the scissors gear due to the weight reduction of the main gear 1 reduces the collision energy between the gear teeth when the teeth strike noise is generated, thereby reducing the volume of the teeth strike noise.

[0030] This disclosure is not limited to the above-described embodiments, and various modifications are possible without departing from its spirit. [Industrial applicability]

[0031] The scissors gear of this disclosure is useful for gears used as a power transmission mechanism. [Explanation of symbols]

[0032] 1 Main Gear 2 Sub-gear 3 springs 11 gear teeth 12 Bearing section 21 Holding part 22 Fitting part 23 gear teeth 24 Storage Unit 31, 32 End 100 Scissors Gear

Claims

1. A main gear having a bearing portion that protrudes in the axial direction and is rotatable around the axis, A sub-gear that is rotatable relative to the main gear, A scissors gear comprising a biasing member having both ends, wherein one end of the biasing member biases the main gear in one direction of rotation, and the other end biases the sub-gear in the other direction of rotation, The aforementioned sub-gear is A holding portion that holds a plurality of gear teeth provided at predetermined intervals on the outer surface, It has a fitting portion which is arranged in the same axial direction as the main gear, and which is positioned inside the holding portion without contacting the holding portion, and which is fitted into and fixed to the bearing portion, The biasing member is positioned in the space formed between the fitting portion and the holding portion. Of the two ends, one end is fixed to the fitting portion, and the other end is fixed to the holding portion. Scissors Gear.

2. The aforementioned end is welded to the outer circumferential surface of the fitting portion, The other end is welded to the inner circumferential surface of the holding portion. The scissors gear according to claim 1.

3. The aforementioned end is connected to a pin provided on the outer circumferential surface of the fitting portion, The other end is connected to a pin provided on the inner circumferential surface of the retaining portion. The scissors gear according to claim 1.

4. A sub-gear used in the scissors gear described in claim 1.

Images