JP2002181162A - Meshing noise reducing gear - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gear capable of reducing the meshing noise generated in meshing with each other. SOLUTION: A drawer of an image forming device has a rear frame 3. A driving gear G1 is fitted to a spindle 8 press fitted to a fixing tool 7 engaged with a mounting hole 6b of the rear frame 3, a C-clip 10 is mounted on an end part of the spindle 8, and the driving gear G1 is rotatably supported on the spindle 8. A shaft BHa with a driven gear G4 is rotatably supported on an oil retaining bearing 9 fitted to a mounting hole 6c of the rear frame 3. The driving gear G1 and the driven gear G4 are provided with back lashes. The driven gear G4 is formed by integrally molding a main driven gear G4a made of a hard resin and meshed with the driving gear G1 to receive the torque, and a sub-driven gear G4b made of a soft resin and overlapped to the main driven gear G4a in a state that it is slightly shifted to an upstream side in the rotating direction with the approximately same shape.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a meshing sound reduction gear that reduces meshing noise generated when meshing with each other. Such a meshing sound reduction gear is suitably used for an image forming apparatus that requires reduction of gearing noise.

[0002]

2. Description of the Related Art Conventionally, gears are often used to transmit rotational force in a paper transport system, a fixing device drive system, and the like of an image forming apparatus. In such a gear, gear noise (gear of gear engagement) is generated at the time of gear engagement.

As a technique for reducing the meshing noise of the gear, the following technique (J01) is conventionally known. (J01) Technology described in Japanese Patent Application Laid-Open No. 7-52494. In this publication, in a drive system having a pair of gears of a recording apparatus, the teeth of the drive gear are arranged on the same axis as the teeth of the driven gear and the driven gear. A technique is described in which the toothed surface of a driven gear is pressed between toothed surfaces of a drive gear and a toothed surface of a driven gear, and the driven gear and the gear for backlash adjustment are prevented from swinging. However, according to this technique, when the drive gear and the driven gear are made of a hard material such as metal or hard plastic, the shock generated when the gears mesh with each other cannot be absorbed. Therefore, it is necessary to reduce the gear meshing noise, particularly the impact noise generated by the sudden gear meshing during driving.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and has an object of the following (O01). (O01) To provide a meshing sound reduction gear capable of reducing a meshing sound generated when gears mesh with each other.

[0005]

Means for Solving the Problems Next, the present invention which has solved the above-mentioned problems will be described. Elements of the present invention include elements of the embodiments to facilitate correspondence with the elements of the embodiments described later. Are added as if they were enclosed in parentheses. The reason why the present invention is described in correspondence with the reference numerals of the embodiments described below is to facilitate understanding of the present invention and not to limit the scope of the present invention to the embodiments.

(1st invention) In order to solve the aforementioned problem,
The meshing sound reducing gear according to the first invention has the following configuration requirements (A0
1) and (A02) are provided. (A01) a meshing sound reduction gear (G2) having a rotational force transmission gear (G2a) made of a high-rigidity material and an impact mitigation gear (G2b) made of an elastic material superposed and coupled in the axial direction; (A02) When the meshing sound reduction gear (G2) meshes with another gear (G1), the shock absorbing gear (G2b) is connected to the other gear (G1) before the rotational force transmission gear (G2a). The meshing sound reduction gear (G2) configured to mesh.

(Operation of the First Invention)
The meshing sound reducing gear (G2) of the present invention is such that when the meshing sound reducing gear (G2) meshes with another gear (G1), the shock absorbing gear (G2b) made of an elastic material has a high rigidity torque transmitting gear. Other gears (G1) before (G2a)
Therefore, the impact noise at the start of the engagement is reduced. For this reason, the meshing sound generated when the meshing sound reduction gear (G2) meshes with the other gear (G1) is the meshing sound generated when the rotational force transmitting gear (G2a) meshes directly with the other gear (G1). It is reduced in comparison.

(Second Invention) A meshing sound reducing gear according to a second invention is characterized by having the following configuration requirement (A03). (A03) the rotational force transmitting gear (G2a) having substantially the same shape as the rotational force transmitting gear (G2a) and being coupled to the rotational force transmitting gear (G2a) in a state of being slightly shifted in the rotational direction with respect to the rotational force transmitting gear (G2a) Shock mitigation gear (G2b).

(Operation of the Second Invention)
In the meshing sound reducing gear (G2) of the present invention, the rotational force transmitting gear (G2a) and the shock absorbing gear (G2b) are formed to have substantially the same shape, and the rotational force transmitting gear (G2a) has the shock absorbing gear (G2a). G2b) can be easily manufactured by joining them in a state shifted slightly in the rotation direction. When the meshing sound reduction gear (G2) of the second invention is used as a drive gear, the rotational force transmitting gear (G2
By using the shock absorbing gear (G2b) slightly shifted forward in the rotation direction with respect to a), it is possible to reduce the noise of meshing with the driven gear. In the case where the meshing sound reducing gear (G2) of the second invention is used as a driven gear, the rotational force transmitting gear (G2
By using the shock absorbing gear (G2b) slightly shifted rearward in the rotation direction with respect to a), it is possible to reduce the noise of meshing with the drive gear.

(Third invention) In order to solve the above problems,
The meshing sound reduction gear of the third invention has the following configuration requirements (A0
4). (A04) The shock absorbing gear (G1b) having a shape that is positively shifted with respect to the torque transmitting gear (G2a).

(Operation of the third invention)
In the meshing sound reducing gear of the present invention, the meshing sound reducing gear (G2) rotates in a predetermined rotation direction or a reverse rotation direction.
Is engaged with another gear (G1), the torque transmitting gear (G
2a), the shock absorbing gear (G2b) made of an elastic material meshes with the other gear (G1), and then the high-rigidity torque transmitting gear (G2a) and the other gear (G1) are engaged. Mesh with each other. Therefore, the meshing sound reducing gear (G2) of the third invention can reduce the meshing sound similarly to the meshing sound reducing gear (G2) of the first invention. In addition, the shock absorbing gear (G2
The meshing sound reduction gear (G2) having b) can reduce the meshing sound regardless of whether the gear is used as a drive gear or a driven gear.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (Embodiment 1) An engagement noise reducing gear according to Embodiment 1 of the present invention is characterized in that the gear according to the present invention has the following configuration requirement (A05). And (A05) One shock absorbing gear (G
2b) and a pair of the rotational force transmitting gears (G2a) coupled to both side surfaces thereof.
2).

(Operation of the First Embodiment) In the meshing sound reducing gear of the first embodiment of the present invention having the above-described structure, the shock absorbing gear (G) sandwiched between the torque transmitting gears (G2a).
After the gear 2b) meshes with the other gear (G1), the highly rigid torque transmitting gear (G2a) meshes with the other gear (G1). Therefore, the meshing sound generated when the meshing sound reduction gear (G2) meshes with another gear (G1) can be reduced.

EXAMPLES Next, specific examples (examples) of the embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to the following examples. (Embodiment 1) FIG. 1 is an explanatory view of a drive gear and a driven gear, FIG. 1A is a front view of the drive gear and a driven gear, and FIG.
FIG. 1B is a view of the driving gear and the driven gear of FIG. 1A viewed from an arrow IB. FIG. 2 is an enlarged view of a main part of the driving gear and the driven gear of FIG. 1B. In FIG. 1, a pair of shaft support portions 1, 1 (only one is shown) that are arranged apart from each other rotatably support a drive roller shaft 4 and a driven roller shaft 5 via bearings 2, 3. . A drive roller (not shown) for transporting the paper is fixed to the drive roller shaft 4, and a driven roller (not shown) for transporting the paper is fixed to the driven roller shaft 5. These drive rollers rotate while contacting each other, and have a function of transporting the image recording paper transported to the contact portion to the downstream side.

A drive gear G1 is press-fitted and fixed to the drive roller shaft 4 to which the drive roller (not shown) is fixed. A driven gear G2 is press-fitted and fixed to the driven roller shaft 5. The drive gear G1 is configured to mesh with a torque transmission gear (not shown) to transmit torque, and to rotate the drive gear G1 to a driven gear G2 meshed with the drive gear G1. The driven gear G2 includes a main driven gear G2a (rotational force transmission gear) and a sub driven gear G2b.
(Impact mitigation gear). The main driven gear G2a is formed of a high rigidity hard resin such as POM (polyoxymethylene), and the sub driven gear G2b is formed of a low rigidity soft resin such as polyurethane. The driven gear G2b has substantially the same shape as the main drive gear G2a, is slightly shifted toward the upstream side in the rotational direction, and is integrally formed. The following method can be adopted as a method of integrally configuring the sub driven gear G2b and the main drive gear G2a. (1) A method in which a gear having a higher melting point is formed first, and the gear having a lower melting point is integrally formed with the gear having a higher melting point in a state where the gear is arranged in a cavity for manufacturing a gear having a lower melting point.

The teeth of the main driven gear G2a are chamfered on the side of the sub driven gear G2b, and the teeth of the sub driven gear G2b are chamfered.
A clearance groove G2c is formed between the teeth. Due to the clearance groove G2c, the teeth of the sub driven gear G2b
When pressed by one tooth, it can spread in the tooth width direction and can be easily deformed. In the first embodiment, the tooth thickness of the driven gear G2 and the driving gear G1
Are formed to have substantially the same thickness. The material of the sub driven gear G2b is about 1/10 of the standard POM.
Polyurethane having a Young's modulus of 3 is preferred.

(Operation of the First Embodiment) In the first embodiment of the meshing sound reducing gear according to the present invention having the above-described configuration, when a rotational force is transmitted from a rotational force transmission gear (not shown) to the drive gear G1, the drive gear G1 is driven. The tooth flank on the downstream side in the rotational direction of the tooth presses the tooth flank on the upstream side in the rotational direction of the tooth of the sub driven gear G2b. At this time, the sub driven gear G2b pressed by the teeth of the drive gear G1
The teeth spread slightly in the width direction of the teeth, and are elastically deformed so as to bend in the rotation direction, thereby absorbing impact energy to reduce impact. Next, when the rotation-direction upstream tooth surface of the teeth of the sub driven gear G2b pressed against the rotation direction downstream tooth surface of the drive gear G1 is aligned with the rotation direction upstream tooth surface of the teeth of the main driven gear G2a, The tooth surface of the drive gear G1 on the downstream side in the rotation direction collides with the tooth surface of the main driven gear G2a on the upstream side in the rotation direction. At this time, the driving gear G1 presses the sub driven gear G2b while the main driven gear G2
a, the impact at the time of collision between the drive gear G1 and the main driven gear G2a at the time of contact is small, and the impact sound is also small. The main driven gear G2a is pressed by the driving gear G1 rotating in the direction of arrow A in FIG.

In the first embodiment, the sub driven gear G2b only needs to reduce the impact and does not need to have the function of transmitting the rotational force. Therefore, the sub driven gear G2b does not require much gear accuracy. Easy to manufacture. Also,
The clearance groove G2c of the driven gear G2 accommodates a portion of the sub driven gear G2b which is pressed by the driving gear G1 and is elastically deformed and swells in the width direction. Therefore, the engagement between the drive gear G1 and the main driven gear G2a can be smoothly performed.

(Embodiment 2) FIG. 3 is an explanatory view of Embodiment 2 of the meshing sound reduction gear of the present invention, and FIG.
FIG. 3B is a view corresponding to FIG. 3A, and FIG. 3B is a view seen from the direction IIIB in FIG. 3A. In the description of the second embodiment, components corresponding to the components of the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted. Example 2
Is different from the first embodiment in the following points, but is configured similarly to the first embodiment in other points. In FIG. 3, the two main driven gears G2a have substantially the same shape and the tooth positions are aligned so that they can mesh simultaneously, and the sub driven gear G2b has substantially the same shape as the main driven gear G2a.
As in the case of the first embodiment, they are integrally formed in a state of being slightly shifted toward the upstream side in the rotation direction and superimposed. The corners of the teeth of the main driven gear G2a are chamfered to form clearance grooves G2c with the sub driven gear G2b. Thus, when the drive gear G1 and the driven gear G2 mesh with each other, the teeth of the drive gear G1 hit the teeth of the sub driven gear G2b and then simultaneously contact the teeth of the two main driven gears G2a. Therefore, after the impact energy is absorbed by the sub driven gear G2b, the teeth of the drive gear G1 abut against the teeth of the two main driven gears G2a. At this time, the driving gear G1 is a sub driven gear G2.
Since it collides with the two main driven gears G2a while pressing b, the impact at the time of collision between the drive gear G1 and the main driven gear G2a is reduced. Therefore, the impact sound (meshing sound) is reduced.

(Embodiment 3) FIG. 4 is an explanatory view of Embodiment 3 of the meshing sound reduction gear of the present invention, and FIG.
FIG. 4B is a diagram corresponding to FIG. 4A, and FIG. 4B is a diagram viewed from the IVB direction in FIG. 4A. In the description of the third embodiment, the same reference numerals are given to the components corresponding to the components of the first embodiment, and the detailed description is omitted. Example 3
Is different from the second embodiment in the following points, but is configured similarly to the second embodiment in other points. In the second embodiment, the sub driven gear G2b is interposed between the two main driven gears G2a. However, in the third embodiment,
The sub driven gear G2b is superposed on both sides of the main driven gear G2a.

In FIG. 4, in the third embodiment, the two sub driven gears G2b have substantially the same shape as the main driven gear G2a, and their teeth are aligned on the upstream side in the rotational direction so that they can be meshed simultaneously. It is formed integrally by shifting and overlapping. Both corners of the teeth of the main driven gear G2a are chamfered to form a clearance groove G2c between the main driven gear G2a and the sub driven gear G2b. The third embodiment is also similar to the second embodiment.
In the same manner as described above, the meshing noise between the driven gear G2 and the drive gear G1 can be reduced.

(Embodiment 4) FIG. 5 is an explanatory view of Embodiment 4 of the meshing sound reduction gear of the present invention, and FIG.
FIG. 5B is a view corresponding to A, and FIG. 5B is a view seen from the direction of the arrow VB in FIG. FIG. 6 is an enlarged view of a main part of FIG. 5B. In the description of the fourth embodiment, the first embodiment will be described.
The same reference numerals are given to constituent elements corresponding to the above-mentioned constituent elements, and detailed description thereof will be omitted. The fourth embodiment differs from the second embodiment in the following points, but has the same configuration as the second embodiment in other points. In the second embodiment,
In the fourth embodiment, a sub driven gear G2b having substantially the same shape is sandwiched between two main driven gears G2a while being displaced toward the upstream side in the rotational direction, and is superposed and integrally formed. Then, two main driven gears G
The sub driven gear G2b, which is positively displaced with respect to the main driven gear G2a, is interposed between the main driven gear G2a and is integrally formed. The two main driven gears G2a are:
The teeth have substantially the same shape and the positions of the teeth are aligned so that they can be engaged simultaneously. The sub driven gear G2b is connected to the main driven gear G
2a, the main driven gear G
As compared with 2a, the tip circle (outer diameter) and the root circle are each larger, and the tooth thickness on the tip side is also thicker. The sub driven gear G2b is integrally formed in a state where the center of the tooth profile of the main driven gear G2a is substantially coincident with the center of the tooth profile of the main driven gear G2a and is superimposed.

(Operation of Embodiment 4) The drive gear G1 is indicated by an arrow A
When rotated in the direction, the tooth surface of the drive gear G1 on the downstream side in the rotational direction presses the tooth surface of the sub driven gear G2b having elasticity on the upstream side in the rotational direction. Further, the tooth surface of the drive gear G1 on the downstream side in the rotational direction contacts the tooth surface of the main driven gear G2a on the upstream side in the rotational direction, and is pressed, so that the main driven gear G2 is pressed.
2a is rotated in the direction of arrow B. On the other hand, even if the drive gear G1 rotates in the direction opposite to the direction of the arrow A, the downstream tooth surface in the rotation direction of the teeth of the drive gear G1 presses the upstream tooth surface in the rotation direction of the teeth of the sub driven gear G2b. Further, the downstream tooth surface in the rotational direction of the teeth of the drive gear G1 abuts on the upstream tooth surface in the rotational direction of the teeth of the main driven gear G2a and is pressed to rotate the main driven gear G2a in the direction opposite to the arrow B direction. Therefore, even if the drive gear G1 rotates in a predetermined rotation direction or a reverse rotation direction, the drive gear G1 is not rotated by the main driven gear G
The meshing sound generated when meshing with 2a can be reduced.

(Embodiment 5) FIG. 7 is an explanatory view of Embodiment 5 of the meshing sound reduction gear of the present invention, and FIG.
FIG. 7B is a perspective view of the drive gear G1 corresponding to FIG. In the description of the fifth embodiment, the first embodiment will be described.
The same reference numerals are given to constituent elements corresponding to the above-mentioned constituent elements, and detailed description thereof will be omitted. The fifth embodiment differs from the first embodiment in the following points, but has the same configuration as the first embodiment in other points. In FIG. 7, studs 7 and 8 are fixed to the shaft supports 1, 1, respectively. The drive gear G1 and the driven gear G2 have bosses G1a and G2d at their central portions, and shaft holes formed in the bosses G1a and G2d are rotatably supported by the studs 7 and 8, respectively. . In the fifth embodiment, the driving gear G1 and the driven gear G2
The meshing sound when meshing with the meshing can be reduced.

(Modifications) Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, but falls within the scope of the present invention described in the appended claims. Thus, various changes can be made. Modified embodiments of the present invention will be exemplified below. (H01) Instead of using a hard resin such as POM for the main driven gear and a soft resin such as polyurethane for the sub driven gear, use a rigid material such as metal such as SUS for the main driven gear and a soft resin such as polyurethane for the sub driven gear. It is also possible to form each with an elastic material such as. Further, the main driven gear and the sub driven gear can be integrally formed by bonding with an adhesive, connection with a bolt, or the like. (H02) In the present invention, the drive gear and the main driven gear can be combined by changing the material of the material. In this manner, the sound quality of the gear meshing sound may be changed so that the gear meshing sound can be sensuously audibly reduced. (H03) Instead of using the driven gear as a main driven gear as a torque transmitting gear and a sub driven gear as an impact reducing gear, the driving gear may be made up of a torque transmitting gear and an impact reducing gear. is there. (H04) The meshing sound reduction gear of the present invention can be used for a paper conveyance system of an image forming apparatus, a driving system of a fixing device, and the like.
Further, it can also be used for various transport systems or drive systems of information equipment.

[0026]

The above-described meshing sound reduction gear of the present invention has the following features.
The following effects can be obtained. (E01) The meshing noise generated when meshing with each other can be reduced.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a drive gear and a driven gear,
FIG. 1A is a front view of a drive gear and a driven gear, and FIG. 1B is a view seen from the direction of arrow IB in FIG. 1A.

FIG. 2 is an enlarged view of a main part of a driving gear and a driven gear of FIG. 1B.

3 is an explanatory view of a meshing sound reduction gear according to a second embodiment of the present invention. FIG. 3A is a diagram corresponding to FIG. 1A of the first embodiment, and FIG. 3B is a diagram viewed from an arrow IIIB of FIG. 3A. is there.

4 is an explanatory view of Embodiment 3 of the meshing sound reduction gear of the present invention, FIG. 4A is a view corresponding to FIG. 1A of Embodiment 1, and FIG. 4B is a view as seen from an arrow IVB in FIG. 4A. is there.

FIG. 5 is an explanatory view of Embodiment 4 of the meshing sound reducing gear of the present invention, FIG. 5A is a view corresponding to FIG. 1A of Embodiment 1, and FIG. 5B is a view as seen from the direction of arrow VB in FIG. 5A. It is.

FIG. 6 is an enlarged view of a main part of a driving gear and a driven gear of FIG. 5B.

7 is an explanatory view of Embodiment 5 of the meshing sound reduction gear of the present invention, FIG. 7A is a view corresponding to FIG. 1A of Embodiment 1, and FIG. 7B is a perspective view of a drive gear G1.

[Explanation of symbols]

U: image forming apparatus, G1: drive gear, G2a: rotational force transmission gear (main driven gear), G2b: shock absorbing gear (sub driven gear), G2: meshing sound reduction gear (driven gear), BHa: belt drive roll Shaft, 8 ... spindle

Claims (3)

[Claims] 1. An engaging noise reduction gear having the following components (A01) and (A02): (A01) a rotational force transmitting gear made of a highly rigid material; (A02) When the meshing sound reduction gear meshes with another gear, the shock absorbing gear is connected to the other gear prior to the rotational force transmission gear. The meshing sound reduction gear configured to mesh. 2. The method according to claim 1, wherein the following components (A03) are provided.
(A03) The shock absorbing gear having substantially the same shape as the torque transmitting gear and being coupled to the torque transmitting gear in a state of being slightly shifted in the rotational direction with respect to the torque transmitting gear. gear. 3. The method according to claim 1, wherein the following component requirements (A04) are provided.
(A04) The shock absorbing gear having a shape positively shifted with respect to the torque transmitting gear.