JPH0247300Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial application field> The present invention is a one-sided clutch having keyways formed at both ends for attaching parts such as gears, cams, or pulleys of devices such as fax machines and copying machines. Regarding the shaft for use.

<Prior Art> A conventional one-way clutch shaft of this type will be described with reference to FIGS. 7 to 9.

In these figures, reference numeral 1 denotes a shaft for one clutch, and in the center portion of the shaft 1 for one clutch, there is an arcuate outer circumferential surface 2 that is wide in the axial direction.

A one-way clutch 3 is attached to this arcuate outer circumferential surface 2 (see FIGS. 8 and 9).

At both ends in the axial direction sandwiching the arcuate outer circumferential surface 2, there are two flat keyways 4a to 4d along the axial direction.
The key grooves 4a are formed symmetrically, respectively.
4d, parts such as gears, cams, or pulleys of the device are fitted or engaged and fixed.

On the other hand, as an example of manufacturing the clutch shaft 1,
For example, a drawn round bar material is used, and one keyway 4a to 4d is formed at each end of the material by milling.

<Problems to be solved by the invention> However, the conventional example having such a configuration has the following problems.

In the one-way clutch shaft 1 described above, the keyways 4a, 4d and the keyway 4 at both ends are
If the flat parts b and 4c are required to be formed on the same plane and parallel to each other, each of the key grooves 4a to 4d is formed one by one by milling, etc. The machining itself was troublesome, and it was also difficult to control the machining precision, such as the parallelism and inclination between the key grooves.

As a means to solve the above-mentioned problem, the applicant considered forming a keyway continuously over the entire length of the shaft for one clutch. However, it was found that there were the following problems, and it would be difficult to put it into practical use as it was.

This point will be explained with reference to FIG.

In the figure, 3b indicates a roller, and when the clutch shaft 1a is not installed, the roller 3b is pressed against the outer ring 3a of the clutch and the retainer 3d by a spring member 3c, as indicated by a solid line in the figure. It moves from the position to the position shown by the broken line and is held at that position by the spring force of the spring member 3c and the protrusion 3e formed at the inner diameter end of the pocket 3f of the retainer 3d, and the roller 3b moves radially inward. Falling off is prevented.

Here, the reference numeral 7 indicates a virtual inscribed circle (dotted chain line) of the roller 3b when the roller 3b is located at the broken line position.
It shows.

When the shaft 1a is installed in this state, the roller 3
b moves against the biasing force of the spring member 3c to the position shown by the solid line in the figure, and performs a normal one-way clutch action at that position.

However, when the keyway 5 is formed over the entire length of the shaft 1a in the axial direction, the keyway 5
The upper roller 3b moves to the position shown by the broken line in the figure, and while the shaft 1a is rotating (idling) in the L direction in the figure, each roller 3b repeats reciprocating movement between the solid line position and the broken line position. .

Therefore, when the rotational direction of the shaft 1a switches to the R direction in the figure (when attempting to lock),
When the roller 3b happens to be moving from the solid line position to the broken line position, the roller 3b becomes locked near the edge portion 6 on the keyway 5.

Immediately after the roller 3b is locked near the edge portion 6, the locked roller 3b is moved to the outer ring 3.
Push the cam surface of a slightly outward elastically. Then, the lock of the roller 3b between the edge portion 6 and the cam surface is momentarily released. Therefore, the arcuate outer circumferential surface 1b following the edge portion 6 that the roller 3b was in contact with
The roller 3b turns around to the inner end portion of the roller 3b, and due to this turning and the elastic return of the cam surface inward, the roller 3b is slightly displaced from the broken line position to the solid line position. As the shaft 1a continues to rotate, the roller 3b is locked between the arcuate outer peripheral surface 1b and the cam surface. Locking by the arcuate outer circumferential surface 1b is different from locking by the edge portion 6, and is performed stably. Considering the roller 3b as the main body, this means that the roller 3b passes over the edge portion 6 and reaches the arcuate outer circumferential surface 1b, moves relatively slightly on the arcuate outer circumferential surface 1b, and then is completely locked. be. That is, the roller 3b is temporarily unlocked between the time when the edge portion 6 starts locking and the arcuate outer circumferential surface 1b completes stable locking. To release this lock, the cam surface is
Since the load applied to the arcuate outer circumferential surface 1b of the shaft 1a is reduced through the transfer, the above-mentioned transfer occurs rapidly. As a result, torque fluctuations may occur during the locking of the roller 3b, or the shaft 1 may
A problem arises in that the time and angle required from the start of reversal of a to locking also increase.

Furthermore, although not shown, a roller 3b located on the arcuate outer circumferential surface 1b near the edge portion 6
During the above-described operation, the roller 3b suddenly moves over the edge portion 6 from the arc-shaped outer circumferential surface 1b and is displaced onto the keyway 5, and suddenly shifts to a free state.

The present invention was devised in view of these circumstances, and on the one hand, it is possible to improve the machining accuracy of the keyway of the clutch shaft and reduce the number of machining steps. It is an object of the present invention to provide a shaft for a clutch which is almost equivalent to the case where a shaft is used.

<Means for solving the problems> In order to achieve the above purpose, the present invention has the following configuration.

That is, the one-way clutch shaft according to the present invention includes an outer ring having a cam surface on the inner surface, a retainer integrally engaged with the inner side of the outer ring, and an appropriate number of retainers formed in the circumferential direction of the retainer. It consists of a roller housed in a pocket, and a spring member attached to the retainer that urges the roller toward the cam surface of the outer ring and one end surface of the pocket, and the spring member causes the roller to move toward the cam surface of the outer ring and one end surface of the pocket. A shaft used for a clutch that is prevented from falling radially inward from a retainer, and has a flat keyway continuous over its entire axial length at at least one point on its arcuate outer circumferential surface. The boundary between the keyway and the arcuate outer circumferential surface is chamfered.

<Effect> The effects of the configuration of the present invention are as follows.

Because the keyway formed on the shaft spans the entire axial length, the parallelism of both ends of the keyway,
Improves machining accuracy such as inclination.

Since the boundary between the keyway and the arcuate outer circumferential surface of the shaft is chamfered, even if a locking action occurs when the roller of one clutch is located on this chamfer, the locking action will not occur on the chamfer. The rollers lock without any problem.

Moreover, even if a relative displacement occurs between the shaft and one clutch during locking due to elastic deformation of the outer ring of one clutch, the roller on the keyway side of the chamfer will move from the chamfer to the arcuate outer peripheral surface of the shaft. While it moves smoothly, the roller on the arcuate outer circumferential surface side of the chamfer also moves smoothly from the arcuate outer circumferential surface onto the chamfer, instead of suddenly running over the edge of the keyway as in the conventional case. It disappears.

<Example> Hereinafter, an example of the present invention will be described in detail based on the drawings.

An embodiment of the present invention is shown in FIGS. 1 to 6.

In the illustrated shaft 10 for one clutch, two flat keyways 11 and 12 are continuously formed over the entire length in the axial direction, and the keyways 11 and 12 are opposed to each other in parallel in the radial direction.

This one-way clutch shaft 10 is manufactured simultaneously with the formation of keyways 11 and 12 that are continuous to both ends in the axial direction, for example, by pultrusion molding. Therefore, the machining accuracy of the parallelism, inclination, etc. of both ends of the keyways 11 and 12 is improved.

The boundary between the key grooves 11, 12 and the arcuate outer circumferential surface 14 is chamfered. This chamfered portion is indicated by the reference numeral 13.

FIG. 3 is a longitudinal cross-sectional view of a shaft for one clutch attached to one clutch.

In the figure, reference numeral 20 denotes a one-side clutch that is fitted onto the one-side clutch shaft 10, and this one-side clutch 20 has cam surfaces 21a to 2 at six locations on the circumference.
A cylindrical outer ring 22 with 1f spaced apart from each other, six rollers 23a to 23f arranged at certain positions of the cam surfaces 21a to 21f, and rotating rollers 23a to 23f arranged at approximately equal intervals in the circumferential direction. A retainer 25 having six pockets 24 for movably holding the retainer 25, and a roller 23 attached to the pockets 24 of the retainer 25.
A spring member 26 that presses and biases a to 23f toward the gentle slope of the cam surfaces 21a to 21f is provided.

On the other hand, when the clutch shaft 10 is not installed, the spring member 26 presses the rollers 23a to 23f against one end surface of the pocket 24 of the retainer 25, and the pressing force of the spring member 26 and the pocket 24 of the retainer 25 are The rollers 23a to 23f are prevented from falling off from the retainer 25 in the radial direction by the protrusions 27 formed in the retainer 25.

Note that the rollers 23a to 23f indicated by solid lines in the figure
shows the state when the shaft 10 is installed, and rollers 23a to 23f shown with broken lines are attached to the shaft 10.
This shows the state when it is not installed. Reference numeral 30 is a virtual inscribed circle (dotted chain line) inscribed in the rollers 23a to 23f at the broken line position.

Regarding the chamfered portions 13 of the keyways 11 and 12, the third
This will be explained with reference to the figures and FIG.

The notch depth of the keyways 11 and 12 is set appropriately. In this embodiment, the number of rollers is six, so it is necessary to always use three or more rollers to perform the clutch action. Therefore, the groove width of the flat part of the keyways 11 and 12 is 60 degrees or less from the center of the shaft. This notch depth is set so that the groove width is .

Next, intersection points A and B between the plane parts of the keyways 11 and 12 and the virtual inscribed circle 30 are determined.

Then, the intersection points C and D between the tangent lines 31 and 32 of the virtual inscribed circle 30 that are in contact with the intersection points A and B and the arcuate outer circumferential surface 14 of the shaft 10 are determined.

That is, the rollers 23a to 23f are aligned with the keyways 11 and 1.
When the rollers 23a to 23f are located on the shaft 10 and move to the arcuate outer circumferential surface 14 of the shaft 10,
The points where the shaft 10 and the shaft 10 come into contact are the above-mentioned intersections A and B.
Therefore, it is most effective to perform the chamfering so that the distance from the center point O of the shaft 10 gradually increases to reach the arcuate outer circumferential surface 14 of the shaft 10, starting from the intersection points A and B.

Therefore, in terms of ease of machining, the chamfered portion 13 may be formed on a plane connecting the above-mentioned intersections A and C and intersections B and D, that is, a plane that includes the tangents 31 and 32. However,
The following are more effective chamfer shapes:

That is, the flat parts of the keyways 11 and 12 and the shaft 1
In order to more smoothly connect the arcuate outer circumferential surface 14 of
and a predetermined point on the arcuate outer peripheral surface 14 of the shaft 10.
A chamfered portion 13 is formed by arcuate surfaces that touch at C' and D'.

Specifically, predetermined points C', D' are connected to keyways 11, 1
Two lines 33, 34 forming a central angle α with a width of 2
and the arc-shaped outer circumferential surface 14 of the shaft 10, and the intersection point A is determined based on the value of the radius R obtained by the following formula.
A center point Q of an outer radius R is set from each of points C' and C', and a chamfered portion 13 is obtained from a partial circular arc surface of a radius R passing from this center point Q to the intersection point A and point C'. Similarly, a partial circular arc surface passing through the intersection B and the point D' is formed.

However, 0<α≦(360°/n), n is the number of rollers 23a to 23f of one clutch 20, _R1 is the radius of one clutch shaft 10, and _R2 is the number of rollers 23a to 23f of one clutch 20.
This is the radius of the virtual inscribed circle 30 of 3a to 23f.
That is, if there are six rollers, the keyways 11 and 12
The central angle α of the width is 60 degrees.

Next, the operation will be explained with reference to FIGS. 3 and 5.

On the one hand, the outer ring 22 of the clutch 20 is fixed, and when the clutch shaft 10 is reversed from rotation in the direction of the arrow L to the direction of the arrow R, the one clutch 20 becomes in a locked state. At this time, as shown in Figure 5,
When the rollers 23c, 23f are located on the key grooves 11, 12, the other rollers 23a, 23b, 2
3d and 23e are respectively located on the arcuate outer peripheral surface 14 of the shaft 10, and these four rollers 23a and 2
3b, 23d, and 23e have a normal locking effect.

Next, when rollers 23a, 23d and rollers 23c, 23f are located in the chamfered portions 13 on the keyways 11, 12 as shown in FIG. It becomes locked while moving between the positions of the rollers, but the chamfered portion 13 does not fit into the keyway 1.
The four rollers 23 a, 23 c, 23
d and 23f are the rollers 23 located on the arcuate outer peripheral surface 14 of the shaft 10 at the transition positions of these rollers.
A locking function can be performed normally together with b and 23e.

That is, in the case of the rollers 23a and 23d, the locking torque suddenly fluctuates when the rollers 23a and 23d go over the edge portions 6 (see FIG. 10) of the keyways 11 and 12, which are not chamfered. This can be prevented beforehand, and the rollers 23c, 23
In the case of f, the arcuate outer peripheral surface 14 of the shaft 10
It is possible to prevent the lock from suddenly moving from the lock to the flat surface of the key grooves 11, 12 and suddenly changing from the locked state to the free state.

FIG. 6 is an explanatory diagram showing the lock operating angle, when the lock torque is 3 kgf-cm.

In the figures, reference numeral a indicates a keyway having an outer peripheral surface of a round bar, reference numeral b indicates a keyway with no chamfered edges, and reference numeral c indicates a keyway with a chamfered edge.

As can be seen from the figure, the keyway without chamfered edges locks in the range of 1 to 6.5 degrees, and the round bar shaft locks in the range of 1 to 2 degrees. It can be seen that there is quite a large variation in comparison, but it is shown that the keyway with a chamfered edge locks in a range of 1 to 2.5 degrees, which is almost comparable to the case with a round bar shaft.

In addition, in the above embodiment, one clutch 20
Although the rollers 23a to 23f are described as six, it goes without saying that the number of rollers is not particularly limited, and the locations where the keyways 11 and 12 are formed are not limited to those described in the above embodiments. 1
There are various possible locations, such as one location or three locations. moreover,
The shape of the chamfered portion 13 is not limited to the plane or partially arcuate surface as described above, but may be a combination of a plane and an arcuate surface or a polygonal surface, for example.

<Effect of invention> According to the present invention, the following effects are achieved.

Since the keyway is formed continuously over the entire length in the axial direction, the parallelism of the keyway flat part can be more accurate than in the conventional case where keyways are formed individually, and it is also easier to process. It can be made easier.

In addition, the boundary between the keyway and the arcuate outer circumferential surface is chamfered, and even when locking torque is applied on the chamfered part, the locking state can be maintained normally on the chamfered part, so the edges of the keyway are not angular. It is possible to suppress fluctuations in the lock torque and unnecessary increases in the lock operating angle when the rollers are in the locked state, such as in the case of rollers, and it is possible to stabilize the locked state to be almost the same as in the case of a round bar shaft.

[Brief explanation of the drawing]

1 to 6 show an embodiment of the present invention, in which FIG. 1 is a perspective view showing a shaft for one clutch, FIG. 2 is a perspective view of the shaft for one clutch with one clutch installed, and FIG. 3 is a perspective view of the shaft for one clutch. is a vertical cross-sectional view of the shaft for one clutch with the one clutch installed, FIG. 4 is an explanatory diagram for explaining the procedure for chamfering the edge of the keyway of the shaft for one clutch, and FIG. 5 is a diagram showing the position of the roller on the keyway. FIG. 6 is a vertical cross-sectional view showing the locked state when the lock is locked, and FIG. 6 is an explanatory diagram for explaining the lock operating angle. Also, Figures 7 to 9
The figures show a conventional example, and FIG. 7 is a perspective view of a shaft for one clutch, FIG. 8 is a perspective view of a shaft for one clutch with one clutch attached, and FIG. 9 is a shaft for one clutch with one clutch attached. FIG. Furthermore, FIG. 10 is a cross-sectional explanatory view for explaining the operation of a one-way clutch mounted on a one-way clutch shaft in which a non-chamfered keyway is formed over the entire length. 10...One clutch shaft, 11, 12
... Keyway, 13 ... Chamfered portion, 14 ... Arc-shaped outer peripheral surface, 20 ... One clutch, 21a to 21f
...Cam surface, 22...Outer ring, 23a to 23f...
Roller, 24...Pocket, 25...Cage, 2
6... Spring member.

Claims (1)

[Claims for Utility Model Registration] (1) An outer ring having a cam surface on its inner surface, a cage integrally engaged with the inside of the outer ring, and an appropriate number of pockets formed in the circumferential direction of the cage. and a spring member that is attached to the retainer and biases the roller toward the cam surface of the outer ring and one end surface of the pocket, and the retainer of the roller is A shaft used for a clutch which is prevented from falling radially inward from the clutch, and which has a flat keyway continuous over its entire axial length at at least one point on its arcuate outer circumferential surface. A shaft for a one-way clutch, characterized in that the boundary between the keyway and the arcuate outer circumferential surface is chamfered. (2) The chamfer is formed at the intersections A and B of the imaginary inscribed circle of the roller and the keyway when the roller is pressed against the pocket by the spring member, and at the intersections A and B. an intersection C between the tangent of the virtual inscribed circle and the arcuate outer peripheral surface;
A shaft for a one-way clutch as set forth in claim (1) of the utility model registration filed with D. (3) The shape of the chamfer is from the intersection A to the intersection C.
The one-way clutch shaft according to claim (2), further comprising one or more planes whose distance from the shaft center gradually increases from the intersection B to the intersection D. (4) The shape of the chamfer is from the intersection A to the intersection C.
The shaft for a one-way clutch according to claim (2), which is registered as a utility model, further comprising a curved surface whose distance from the shaft center gradually increases from the intersection point B to the intersection point D. (5) The shape of the chamfer is in contact with the flat surface of the keyway at the intersections A and B, and the shape of the chamfer is in contact with the flat surface of the keyway at the intersections C and D.
4. A shaft for a one-way clutch according to claim 4, which comprises a circular arc surface in contact with the circular arc outer circumferential surface.