JPH08109961A - Scissors gear - Google Patents

Abstract

PURPOSE: To improve the assembly performance and reliability by reducing each abrasion of a torsion ring an d an engagement pin. CONSTITUTION: A scissors gear 10 is equipped with a torsion ring 13, main gear 11 having an engagement pin 11d, and a subgear 12 having an engagement pin 12b. The subgear 12 is installed in a rotatable manner through a torsion ring 13 on the same axis line to the revolution axis of the main gear 11. The torsion ring 13 generates a torsional force for twisting the subgear 12 in the circumferential direction. The recessed parts 11e and 12e into which the head parts of an engagement pin 12b can be intruded are formed on the main gear 11 and the subgear 12. The subgear 12 has a stopper pin 16 in the vicinity of the engagement pin 12b in the installed state on one side surface of the main gear 11. The stopper pin 16 makes contact with the engagement pin 12b before the state where the main gear 12 and the subgear 12 are meshed with the opponent gear, and separates from the engagement pin 12b in the state after the main gear 11 and the subgear 12 are meshed with the opponent gear.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scissors gear which prevents rattling noise caused by backlash which is a clearance between tooth surfaces between a mating mating gear and a main gear.

[0002]

2. Description of the Related Art Conventionally, a sub gear is provided on the same axis as a rotation axis of a main gear meshing with a mating gear, and is provided on one side surface of the main gear so as to be rotatable relative to the main gear and meshing with the mating gear. It is known that a torsion ring is housed between the sub gear and the main gear. The main gear is provided with a first locking pin that locks one end of the torsion ring, and the sub gear is provided with a second locking pin that locks the other end of the torsion ring. One end of the torsion ring is locked to the first locking pin and the other end is locked to the second locking pin, and a torsional force for twisting the sub gear in the circumferential direction with respect to the main gear is generated. Therefore, the elastic force of the torsion ring causes the sub gear to sandwich the teeth of the mating gear together with the teeth of the main gear to eliminate backlash and prevent rattling noise. In the conventional scissors gear configured as described above, the sub gear is twisted so that the torsion ring is widened in advance at the time of assembling, the teeth of the main gear and the teeth of the sub gear are aligned, and then fixed with bolts before being assembled to the device.

[0003]

However, in the above-mentioned conventional scissors gear, since the sub gear and the main gear are fixed with bolts in a twisted state before mounting, the number of parts is increased, and parts management is complicated. . In addition, it is necessary to remove the bolt after assembly, so there was a risk of forgetting to remove it during work. On the other hand, as shown in FIG. 7, the heights of the first locking pin 1d and the second locking pin that lock the torsion ring 3 are set to be lower than the clearance between the main gear 1 and the sub gear 2, and the head ring is assembled to the head. Chamfering is applied to improve the attachability. Therefore, there is a problem that the rattling of the torsion ring 3 reduces the areas of the first and second locking pins that receive the torsional force of the torsion ring 3. This reduction in area promotes wear of the locking portion of the torsion ring 3 and the respective locking pins, thus shortening the service life.

A first object of the present invention is to provide a scissors gear for preventing the wear of the torsion ring and each locking pin by preventing the reduction of the area of each locking pin receiving the torsional force of the torsion ring. Especially. A second object of the present invention is to provide a scissors gear which can reduce the number of parts and improve assemblability and reliability by fixing the sub gear in a twisted state without using bolts. It is in.

[0005]

A configuration of the present invention for achieving the above object will be described with reference to FIG. 1 corresponding to an embodiment. The present invention includes a main gear 11 having a first locking pin 11d that locks one end of the torsion ring 13 and a second locking pin 12b that locks the other end of the torsion ring 13.
And a sub gear 12 having a sub gear 12 which is provided on the same axis as the rotation axis of the main gear 11 and is provided on one side surface of the main gear 11 so as to be rotatable relative to the main gear 11 via a torsion ring 13. The torsion ring 13 has the first and second locking pins 11d, 12
This is an improvement of the scissors gear configured to generate a twisting force for twisting the sub gear 12 in the circumferential direction with respect to the main gear 11 by b. Its characteristic structure is shown in FIGS.
As shown in, the first and second main gear 11 and the sub gear 12 corresponding to the first and second locking pins 11d and 12b are
The recesses 11e and 12e into which the heads of the locking pins 11d and 12b can enter are provided.

Another characteristic configuration of the present invention is a sub gear 1
2 is provided on one side surface of the main gear 11 and has a stopper pin 16 in the vicinity of the first locking pin 11d. As shown in FIG. 6, the stopper pin 16 includes the main gear 11 and the sub gear 12 as the mating gear 14 The first state before meshing with
It is configured such that the main gear 11 and the sub gear 12 are separated from the first locking pin 11d in a state in which the main gear 11 and the sub gear 12 mesh with the mating gear 14 as shown in FIG. The sub gear 12 is the main gear 11
It is preferable that a pin hole 12c is provided in the vicinity of the first locking pin 11d while being provided on one side surface, and the stopper pin 16 is press-fitted into the pin hole 12c.

[0007]

Operation As shown in FIGS. 3 and 4, the torsion ring 1
When both ends of 3 are locked to the locking pins 11d and 11b and the sub gear 12 is fitted into the main gear 11, the locking pins 11d and 11b
The heads of 11b enter into the recesses 11e and 12e, respectively. Also, with both ends of the torsion ring 13 locked, the sub gear 12 is twisted in the direction shown by the solid line arrow in FIG. 1 to open the torsion ring 13, and the stopper pin 16 has crossed over the locking pin 11d as shown in FIG. At this time, the sub gear 12 is fitted into the main gear 11. When the sub gear 12 is released after fitting, the stopper pin 16 contacts the locking pin 11d by the torsional force of the torsion ring 13 as shown in FIG.
When the main gear 11 and the sub gear 12 are meshed with the mating gear 14 in this state, as shown in FIG.
Moves away from the locking pin 11d.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described in detail with reference to the drawings. As shown in FIGS. 1 to 6, the scissors gear 10 in this embodiment has a main gear 11, a sub gear 12, and a torsion ring 13. As shown in FIG. 1, the main gear 11 has a fitting hole 11 at the center for fitting into a shaft (not shown).
a is provided, and the stepped portion 11b into which the sub gear 12 is fitted is provided around the fitting hole 11a. A mounting portion 11c to which the torsion ring 13 is mounted is provided on the side surface of the main gear 11 on the stepped portion side, and the mounting portion 11c has a cylindrical first locking pin 11 to which one end of the torsion ring 13 is locked.
d is provided.

The sub gear 12 is a stepped portion 1 of the main gear 11.
The torsion ring 13 has a hole 12a to be fitted in the 1b.
Has a cylindrical second locking pin 12b that locks to the other end. The hole 12a of the sub gear 12 is provided in the stepped portion 11b of the main gear 11 on the same axis as the rotation axis of the main gear 11 so that it can rotate relative to the main gear 11.

The torsion ring 13 is mounted on the mounting portion 11c of the main gear 11 so as to be sandwiched between the main gear 11 and the sub gear 12 (FIGS. 3 and 4). The torsion ring 13 is formed in a state in which a part of the ring is cut out, and semicircular locking portions 13a, 13a are provided on both end surfaces of the cutout portion. As shown in FIG. Part 13a,
13a is locked to the first and second locking pins 11d and 12b. When the torsion ring 13 is locked and the sub gear 12 is twisted with respect to the main gear 11 in the direction shown by the solid line arrow in FIG. 1, the second locking pin 12 is shown as shown by the solid line arrow in FIG.
b opens the torsion ring 13. When meshed with the mating gear 14 as shown in FIG. 5 in this state, the torsional force of the torsion ring 13 urges the sub gear 12 in the circumferential direction with respect to the main gear 11, and the teeth of the sub gear 12 are the teeth of the mating gear 14. With the teeth of the main gear 11. As a result, the scissors gear 10 can eliminate backlash and prevent rattling noise.

The characteristic first construction of this embodiment is that the main gear 11 corresponding to the first and second locking pins 11d and 12b.
And the first and second locking pins 11d, 12 on the sub gear 12
Recesses 11e and 12e into which the respective heads of b can enter are provided. In this embodiment, as shown in FIG. 1, the main gear 11 and the sub gear 12 are provided with elongated recesses 11e and 12e, respectively, which are elongated in the circumferential direction. As shown in FIG. 3 and FIG. 4, the recesses 11e and 12e have depths into which the heads of the locking pins 11d and 12b can enter and the sub gear 12 is fitted into the main gear 11, as shown in FIGS. Each locking pin 11d,
At least the chamfered portion of the head of 12b can actually enter.

The operation of the scissors gear 10 thus constructed will be described. With the sub gear 12 fitted in the main gear 11, the heads of the respective locking pins 11d and 12b enter into the respective recesses 11e and 12e, so that the locking portion 13a of the torsion ring 13 during operation is the locking ring 13a of the torsion ring 13. Regardless of rattling, they are locked to the body portions of the locking pins 11d and 12b, respectively.

The second characteristic feature of this embodiment is that the first configuration is such that the sub gear 12 is provided on one side of the main gear 11.
The stopper pin 1 is attached to the sub gear 12 near the locking pin 11d.
There is a pin hole 12c into which 6 is press fitted. The position where the pin hole 12c is provided is, as shown in FIG. 5, a stopper that is press-fit with a larger shift amount B as shown in FIG. 6 than the shift amount A when the main gear 11 and the sub gear 12 are meshed with the mating gear 14. This is the position where the pin 16 contacts the locking pin 11d. Therefore, the press-fitted stopper pin 1
When the main gear 11 and the sub gear 12 are in mesh with the mating gear 14, 6 is moved in the direction of the solid line arrow in FIG. 6 and separated from the locking pin 11d.

In the scissors gear 10 thus constructed, the torsion ring 13 is locked, the sub gear 12 is fitted into the main gear 11, and twisted in the direction shown by the solid line arrow in FIG. 1 to open the torsion ring 13. Sub gear 12
The stopper pin 16 is press-fitted after the amount of deviation of the main gear 11 from the main gear 11 reaches a predetermined amount, that is, when the pin hole 12c exceeds the first locking pin 11d. The torsion ring 13 biases the sub gear 12 through the second locking pin 12b so as to twist the sub gear 12 against the main gear 11 in the direction opposite to the solid arrow in FIG.
abut on d. As a result, the scissors gear 10 becomes a counterpart gear 1 of the main gear 11 and the sub gear 12 as shown in FIG.
4 will be locked to each other with a shift amount B larger than the shift amount A in the state of being meshed with 4. When the scissors gear 10 is assembled to the mating gear 14, the shift amount is reduced and the stopper pin 16 is separated from the first locking pin 11d as shown in FIG.

In the second embodiment, the sub gear 1
Although the pin hole 12c into which the stopper pin 16 is press-fitted is provided in 2, the stopper pin 16 may be provided in the sub gear 12 in advance. In this case, the stopper pin 16 may be press-fitted into the pin hole 12c or may be integrally machined. In the scissors gear 10 in which the stopper pin 16 is provided in the sub gear 12 in advance, the torsion ring 13 is locked so that the head of the stopper pin 16 does not contact the head of the first locking pin 11d with respect to the main gear 11. It is inserted up to and twisted in the direction shown by the solid arrow in FIG. 1 to open the torsion ring 13. Main gear 1 of sub gear 12
After the amount of deviation with respect to 1 reaches a predetermined amount, that is, when the stopper pin 16 exceeds the first locking pin 11d, the sub gear 12 is fitted into the main gear 11. Torsion ring 1
The third pin biases the sub gear 12 against the main gear 11 via the second locking pin 12b so that the stopper pin 16 contacts the first locking pin 11d. As a result, as shown in FIG. 6, the scissors gear 10 has a shift amount A in a state in which it is meshed with the mating gear 14 of the main gear 11 and the sub gear 12.
They will be locked together with a larger shift amount B. Further, in the above embodiment, the mounting portion for mounting the torsion ring is provided on the main gear, but it may be provided on the sub gear side.

[0016]

As described above, according to the present invention, since the main gear and the sub gear corresponding to the respective locking pins are provided with the recesses into which the respective heads of the locking pins can enter, the locking is achieved. The heads of the pins respectively enter the recesses, and the locking portions are respectively locked to the body portions of the locking pins. As a result, the area of each locking pin that receives the torsional force of the torsion ring does not decrease, and wear of the locking pin can be reduced. A stopper pin or a pin hole into which the stopper pin can be press-fitted is provided in the sub gear, and the stopper pin or the press-fitted stopper pin abuts the locking pin with a displacement amount larger than the displacement amount when the main gear and the sub gear mesh with the mating gear. Since they come into contact with each other and separate from the locking pin in the state of meshing with the mating gear, it is possible to improve the assembling property and reliability by eliminating the need for a component for locking the main gear and the sub gear.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a scissors gear according to an embodiment of the present invention.

FIG. 2 is a front view in which a torsion ring is attached to the main gear.

FIG. 3 is a sectional view taken along the line CC of FIG. 2 after the gear is assembled.

FIG. 4 is a sectional view taken along line DD of FIG. 2 after the gear is assembled.

5 is an enlarged view of a portion E of FIG. 2 showing a state in which the scissors gear meshes with a mating gear.

FIG. 6 is an enlarged view of an E portion of FIG. 2 showing a state before engagement of the scissors gear.

FIG. 7 is a diagram corresponding to FIG. 3 showing a conventional example.

[Explanation of symbols]

 11 Main Gear 11d First Locking Pins 11e, 12e Recess 12 Sub Gear 12b Second Locking Pin 12c Pin Hole 13 Torsion Ring 14 Mating Gear 16 Stopper Pin

Claims (3)

[Claims] 1. A main gear (11) having a first locking pin (11d) with which one end of the torsion ring (13) is locked, and a second locking pin with which the other end of the torsion ring (13) is locked. (12
b) having a sub gear (12), the sub gear (12) is provided on the same axis as the rotation axis of the main gear (11), and the main gear (11) is provided on one side surface of the main gear (11).
The torsion ring (13) is rotatable relative to
And the torsion ring (13) is connected to the main gear (1) by the first and second locking pins (11d, 12b).
In a scissors gear configured to generate a torsional force for twisting the sub gear (12) in the circumferential direction with respect to 1), the sub gear (12d corresponding to the first and second locking pins (11d, 12b) ) And the first and second main gear (11)
Recesses where the heads of the locking pins (11d, 12b) can enter
(12e, 11e) is arranged, the scissors gear. 2. A main gear (11) having a first locking pin (11d) with which one end of a torsion ring (13) is locked, and the main gear (11) provided on the same axis as the rotation axis of the main gear (11). 11) has a sub gear (12) provided on one side surface of the torsion ring (13) so as to be rotatable relative to the main gear (11), and the sub gear (12) is provided. The ring (13) generates a twisting force that twists the sub gear (12) in the circumferential direction with respect to the main gear (11) and meshes the main gear (11) and the sub gear (12) with a mating gear (14). In the scissors gear configured as described above, the sub gear (12) has a stopper pin (16) in the vicinity of the first locking pin (11d) while being provided on one side surface of the main gear (11), The stopper pin (16) has the main gear (11) and the sub gear (12) as the mating gear (14). Before contacting the first locking pin (11d) and after engaging the main gear (11) and the sub gear (12) with the mating gear (14), the first locking pin (11d) ) Scissors gear characterized in that it is configured to separate from. 3. A stopper pin (16) provided with a pin hole (12c) near the first locking pin (11d) with the sub gear (12) provided on one side surface of the main gear (11). The scissors gear according to claim 2, wherein is pressed into the pin hole (12c).