JP7803908B2 - Switch device and shaft support structure - Google Patents

Description

The present invention relates to a switch device and a shaft support structure.

Patent document 1 discloses a steering wheel equipped with paddle shift switches.

JP 2011-063260 A

Some paddle shift switches of this type have a case fixed to the steering wheel and an operating knob rotatably supported by the case. The operating knob has a support tube (connecting part) that is fitted onto and connected to the shaft. The case has a pair of wall parts arranged opposite each other with a gap between them, each with a support hole that supports one end and the other longitudinal end of the shaft.

The operation knob and shaft are connected using the following procedure: (a) The operation knob is assembled to the main case, and the support tube (connector) is positioned coaxially with the support hole provided in the wall of the main case. (b) The shaft is inserted into the case through the support hole in one wall and passes through the support tube, and then inserted into the support hole in the other wall. This allows the operation knob to be rotatably supported by the shaft supported by the case.

If the shaft moves in the insertion direction and falls out of the support hole, it will interfere with the operation of the control knob. For example, it is conceivable to restrict the movement of the shaft by using a pair of support arms provided inside the case.
In this case, movement of the shaft can be restricted as follows: (a) A pair of support arms are arranged in a position in the case where they hold the shaft from both sides, and the shaft is inserted between the pair of support arms in the process of moving the shaft from one support hole to the other support hole.

Here, the shaft is inserted between the pair of support arms while elastically displacing the pair of support arms in directions away from each other, so the pair of support arms need to be able to elastically displace in directions away from each other while withstanding the stress caused by the insertion of the shaft.
When the base ends of the support arms in the longitudinal direction are supported by the case, in order to allow the support arms to elastically deform while withstanding the stress caused by the insertion of the shaft, it is necessary to do the following: (a) Set the position in the pair of support arms where the shaft is inserted at a position on the tip side of the support arms in the longitudinal direction, as far away from the base ends as possible.
This increases the length of the support arm, resulting in an increase in the size of the case that accommodates the support arm.

Therefore, there is a demand for a mechanism that can restrict longitudinal movement of the shaft while avoiding an increase in the size of the case.
In addition to such requirements, another objective of the present invention is to achieve actions and effects derived from the various configurations disclosed in the "Forms for Implementing the Invention" described below, which actions and effects cannot be obtained with conventional technologies.

The present invention provides
Case and
a shaft supported by the case;
an operation knob rotatably supported by the shaft,
The case is
a first wall portion and a second wall portion spaced apart in a longitudinal direction of the shaft;
a first support hole provided in the first wall portion and supporting one end side of the shaft in the longitudinal direction;
a second support hole provided in the second wall portion and supporting the other end of the shaft in the longitudinal direction;
support arms disposed on one side and the other side of the shaft as viewed from a central axis direction along the longitudinal direction of the shaft,
The support arm is
an engaging portion provided in a direction intersecting the central axis when viewed from a radial direction of the central axis and having a length capable of engaging with an outer periphery of the shaft;
The connector is provided in a direction along the central axis and has a connection portion that connects the engagement portion and the case.

This invention makes it possible to restrict longitudinal movement of the shaft while avoiding an increase in the size of the case.

FIG. 2 is a diagram illustrating a switch device. FIG. 2 is a diagram illustrating a switch device. 10A and 10B are diagrams illustrating parts of the case that support the shaft. FIG. FIG. FIG. 10A and 10B are diagrams illustrating displacement of the support arm during the process of assembling the shaft to the case. 10A and 10B are diagrams illustrating displacement of the support arm during the process of assembling the shaft to the case. 10A and 10B are diagrams illustrating a support arm according to a modified example. 10A and 10B are diagrams illustrating a shaft according to a modified example.

Embodiments of the present invention will be described below using as an example a switch device 1 attached to the steering wheel of a vehicle. This switch device 1 has an operating knob 3 that is operated by the driver when performing an upshift or downshift. The switch device 1 is a switch device for a so-called paddle shift switch.

1 and 2 are diagrams illustrating the switch device 1. Fig. 1(A) is a perspective view of the switch device 1. Fig. 1(B) is an exploded perspective view of the switch device 1. Fig. 2 is a view of the case 2 of the switch device 1 as seen from the assembly direction of the operation knob 3. Fig. 2 corresponds to a view of the switch device 1 attached to a steering wheel (not shown) as seen from the front side of the vehicle.
3A and 3B are diagrams illustrating the portions of the case 2 that support the shaft 4. Fig. 3A shows an enlarged view of the portions of the case 2 that support the shaft 4. Fig. 3B shows the shaft 4 supported by the portions that support the shaft 4 shown in Fig. 2A.
4 is an enlarged view of a main part of the switch device, which schematically shows the support hole 24 as viewed from the direction AA in FIG.
5 and 6 are cross-sectional views of the switch device 1. Fig. 5A schematically shows a cross section of the switch device 1 taken along plane A in Fig. 1. Fig. 5B schematically shows a cross section taken along line A-A in Fig. 5A. Fig. 6 schematically shows a state in which the shaft 4 is omitted from Fig. 5A.

2, the main parts of the operating knob 3 to be attached to the case 2 are shown by phantom lines. In this Fig. 2, to make the position of the peripheral wall 22 of the case 2 easier to understand, the end face of the peripheral wall 22 on the front side of the page is shown with hatching. Furthermore, in Fig. 2 and Figs. 3A and 3B, to make the position of the opening 227 provided in the case 2 easier to understand, the opening 227 is shown with cross hatching.
In the following description, the positional relationship of each component will be described based on the vertical direction (vertical direction in FIG. 2 ) when the switch device 1 is attached to a steering wheel (not shown), as needed. For example, when the term "upper side" is used, it means the upper side in the vertical direction in FIG. 2 .

As shown in FIG. 1 , the switch device 1 has a resin case 2 , a shaft 4 supported by the case 2 , and an operating knob 3 rotatably supported by the shaft 4 .
2, the case 2 has a bottom wall portion 21 and a peripheral wall portion 22 that completely surrounds the outer periphery of the bottom wall portion 21. The case 2 has a cylindrical shape with a bottom that is open on the front side of the paper.
The case 2 has a generally rectangular shape when viewed from the front. The surface of the case 2 facing the back of the drawing is a mounting surface for a steering wheel (not shown).

The peripheral wall portion 22 is formed in a cylindrical shape from side wall portions 221 and 222 that are parallel to each other and side wall portions 223 and 224 that connect the ends of the side wall portions 221 and 222 to each other.
Support holes 23, 24 for the shaft 4 are provided at one end (side wall 223 side) of the side wall portions 221, 222 in the longitudinal direction (left-right direction in the figure). The support holes 23, 24 penetrate the side wall portions 221, 222 in the thickness direction (up-down direction in FIG. 2A).
3A, the support holes 23, 24 are provided to support one and the other longitudinal ends of the shaft 4. Therefore, the support holes 23, 24 are provided in the side wall portions 221, 222 in regions that intersect with the axis X (the central axis of the shaft 4) that extends along the longitudinal direction of the shaft 4.
5, the support holes 23, 24 are formed with an inner diameter slightly larger than the outer diameter D4 of the shaft 4. The support holes 23, 24 are provided concentrically with the axis X as the reference.

When viewed from the direction of the axis X, the basic shape of the support holes 23, 24 is a circle (see FIG. 4) having an inner diameter that matches the outer diameter of the base portion 40 of the shaft 4 (see FIG. 5A).
As shown in Fig. 4, protrusions 241 are provided on the inner periphery of the support hole 24. When viewed from the direction of the axis X, the protrusions 241 are arch-shaped with their linear side surfaces 241a positioned on the axis X side. The side surfaces 241a of the protrusions 241 are positioned closer to the axis X than the tangent line L of the circular support hole 24 and are parallel to the tangent line L. In this embodiment, the protrusions 241 are provided at 120° intervals in the circumferential direction around the axis X.

In this embodiment, preferably, when the shaft 4 is inserted into the support hole 24, the shaft 4 passes through the support hole 24 while pushing the protrusions 241 outward in the radial direction. As a result, the protrusions 241 are in pressure contact with the outer periphery of the shaft 4 at the support hole 24. In other words, the shaft 4 is supported in a press-fit state in the support hole 24 having the protrusions 241.
This makes it possible to more reliably restrict movement of the shaft 4 in the longitudinal direction (the direction of the axis X).
It is sufficient that the protrusion 241 is provided in at least one of the support holes 23 and 24. The total number of protrusions 241 in the support hole 24 can also be changed arbitrarily.

5, the shaft 4 has a cylindrical base 40. For example, the base 40 is a rod-shaped member made of metal or a rod-shaped member made of resin with a plated surface. For example, the shaft 4 is preferably harder than the resin case 2.
The base 40 has a recess 41 formed in the approximate center in the longitudinal direction. The recess 41 is formed with a width W41 in the direction of the axis X. The recess 41 is formed in the base 40 over the entire circumference in the circumferential direction around the axis X (see FIG. 5B). The region of the base 40 where the recess 41 is formed has a smaller outer diameter than the other regions.
In this embodiment, when one end 4a and the other end 4b of the shaft 4 are supported by the support holes 23 and 24 of the case 2, the recess 41 is positioned at a position that intersects with a straight line (center line C) that passes through the center of the width direction (left-right direction in Figure 4) of the case 2.

In this state, the connecting portions 34, 34 on the operation knob 3 side are fitted onto one end 4a and the other end 4b of the shaft 4. The connecting portions 34, 34 are provided on the surface of the cover portion 31 facing the bottom wall portion 21 (the lower surface in FIG. 5 ). The connecting portions 34, 34 are provided parallel to each other and spaced apart in the width direction of the cover portion 31 (the direction of the axis X).
The connecting portions 34 are provided with insertion holes 341 that penetrate the connecting portions 34 in the thickness direction. The shaft 4 penetrates the insertion holes 341 in the direction of the axis X. The insertion holes 341 are formed with an inner diameter slightly larger than the outer diameter D4 of the shaft 4. Therefore, the connecting portions 34 are loosely fitted into the shaft 4. The operating knob 3 is supported by the shaft 4 in a state where it is allowed to rotate about the axis X.

1 and 2, the operation knob 3 has a cover portion 31, an operation portion 32, and a connection portion 33. The cover portion 31 is formed to have a size and shape that allows it to cover the opening of the peripheral wall portion 22 on the case 2 side.
The operating unit 32 is connected to the cover unit 31 via a connecting portion 33. As shown in Fig. 2, the connecting portion 33 extends along the center line C in a direction away from the axis X (to the left in the drawing). The connecting portion 33 connects the cover unit 31 and the surface of the operating unit 32 facing the cover unit 31 (the surface on the far side of the drawing).
When viewed from the opening direction of the peripheral wall 22 (the front side of the drawing), the operation unit 32 is positioned such that its area on the axis X side overlaps with the side wall 224 on the case 2 side. The operation unit 32 has a width W32 in the direction of the center line C that extends beyond the side wall 224 to the outside of the case 2. Furthermore, the operation unit 32 extends to one side (upper side in the drawing) and the other side (lower side in the drawing) as viewed from the center line C. The surface of the operation unit 32 on the front side of the drawing is the operation surface operated by the user.

As shown in FIG. 1, the cover 31 has connecting portions 34, 34 on the side wall 223 side (right side in the figure). The operating knob 3 is cantilevered by the shaft 4 on the connecting portions 34, 34 side, and is rotatable in the circumferential direction around the axis X. Therefore, when the user applies an operating force to the operating portion 32, the operating portion 32 side of the operating knob 3 is displaced toward the case 2 (the far side of the paper in FIG. 2).

2, inside the peripheral wall 22, a rib 225 is provided on the inside of the side wall 223. The rib 225 is provided along the inner periphery of the side wall 223 in the range from one side wall 221 to the other side wall 222 in the direction of the axis X. The rib 225 is located closer to the bottom wall 21 than the peripheral wall 22 (see FIG. 5B).
A rib 226 is also provided on the inside of the peripheral wall 22 on the side of the side wall 224 (left side in the drawing) as viewed from the axis X. The rib 226 is provided along the axis X in a range from one side wall 221 to the other side wall 222 in the direction of the axis X. The rib 226 is located closer to the bottom wall 21 than the peripheral wall 22 (see FIG. 5B ). The rib 225 and the rib 226 are provided in a symmetrical positional relationship with respect to the axis X.

As shown in Figure 2, the area between rib 225 and rib 226 in case 2 forms opening 227. In the area where opening 227 is provided, support portion 211 is provided closer to side wall portion 222 (upper side in the figure) than center line C. Center line C is a straight line that passes through the center of case 2 in the width direction (up-down direction in the figure) and is perpendicular to axis X of shaft 4.

In a top view, the support portion 211 is a band-shaped portion extending in a direction along the center line C. The support portion 211 is provided across the rib 225 and the rib 226, and is provided to ensure strength around the opening 227 in the case 2.
As shown in FIG. 6, the support portion 211 has a height h211 that extends to the vicinity of the axis X and is located closer to the operation knob 3 (upper side in FIG. 6) than the bottom wall portion 21 on the case 2 side.

2, a recess 211b recessed toward the bottom wall 21 is provided on the upper surface 211a of the support portion 211. The recess 211b is a recess having an arc-shaped cross section that follows the outer shape of the shaft 4.
In top view, the recess 211b is provided in a region intersecting with the axis X. The recess 211b extends along the axis X and is provided over the entire width of the support portion 211 (the vertical direction in FIG. 2 ).

A pair of support arms 25A, 25B are provided on the side surface of the support portion 211 on the side wall portion 221 side (the lower side in the figure). The support arms 25A, 25B are provided in a symmetrical positional relationship with respect to the axis X. The support arms 25A, 25B are columnar members with a rectangular cross section, and are formed integrally with the resin case 2 (support portion 211) (see FIG. 6).
The support arms 25A and 25B are formed to have the same basic shape, and the shape of the support arm 25B will be described below as a representative example.

As shown in Fig. 6, the support arm 25B has an engagement portion 251 and a connection portion 252. When viewed from the radial direction of the axis X, the connection portion 252 is provided so as to be oriented along the axis X. One end of the connection portion 252 is connected to the support portion 211. The connection portion 252 is located within an opening 227 provided in the bottom wall portion 21. The connection portion 252 is provided so as not to protrude outward (downward in the figure) from the case 2, utilizing the thickness W21 of the bottom wall portion 21 of the case 2.
Therefore, when viewed from the radial direction of the axis X, the connection portion 252 is provided in a positional relationship where it overlaps with the bottom wall portion 21 of the case 2.

The other end of the connection portion 252 is connected to one end of the engagement portion 251 (the lower end in the figure). As shown in Figure 6, the engagement portion 251 is provided at a position that intersects with the center line C of the width direction of the case 2, and is oriented perpendicular to the axis X. Here, the term "perpendicular to the axis X" in this specification also includes cases where the engagement portion 251 is slightly tilted with respect to the axis X.

6, the engaging portion 251 is substantially perpendicular to the connecting portion 252. The other end (tip 25a) of the engaging portion 251 is located closer to the cover portion 31 than the axis X. The engaging portion 251 is formed with a length L251 that crosses the axis X from the bottom wall portion 21 side to the cover portion 31 side.
The support arm 25B is bent at a connection portion J between the engaging portion 251 and the connecting portion 252. When viewed in the radial direction of the axis X, the support arm 25B has, for example, a substantially L-shape.
In the support arm 25B, an engagement portion 251 is supported by a support portion 211 on the case 2 side via a connection portion 252. The support arm 25B is cantilevered by the support portion 211. The tip 25a of the support arm 25B, on which the engagement portion 251 is provided, is elastically displaceable in the direction of the axis X (the left-right direction in FIG. 6 ) and in the direction perpendicular to the rotation axis X (the left-right direction in FIG. 5B ).

Figures 7 and 8 are diagrams illustrating the displacement of the support arms 25A, 25B during the process of assembling the shaft 4 to the case 2. The operation knob 3 and shaft 4 are connected in the following manner: (a) The operation knob 3 is assembled to the case 2, and the connecting portions 34, 34 are positioned inside the case 2 coaxially with the support holes 23, 24 provided in the side walls 221, 222 (see Figure 6). (b) The shaft 4 is inserted into the case 2 through the support hole 23 in one side wall 221 and passes through the insertion holes 341, 341, and then inserted into the support hole 24 in the other side wall 222 (see Figure 5(A)). As a result, the operation knob 3 is rotatably supported by the shaft 4 supported by the case 2.

Here, if a protrusion is provided on the inner circumference of support hole 23, into which shaft 4 is inserted first, of support holes 23 and 24, the shaft 4 will be pressed into support hole 23 while being pushed into case 2, making it difficult to insert shaft 4.
In this embodiment, of the support holes 23, 24 of the case 2, the support hole 24 into which the shaft 4 is inserted last is provided with a protrusion 241 on the inner periphery. Therefore, the shaft 4 is press-fitted into the support hole 24 at the end of the insertion of the shaft 4 into the case 2. This effectively prevents the insertability of the shaft 4 from becoming poor.
Therefore, when the shaft 4 is inserted into the support hole 24 before the support hole 23 , a protrusion is provided on the inner periphery of the support hole 23 .

As described above, Fig. 2 shows the switch device 1 attached to the steering wheel (not shown) as seen from the front of the vehicle. In this state, the shaft 4 is oriented vertically. Therefore, gravity acts on the shaft 4 in a direction that moves the shaft 4 downward in Fig. 2.
When the vehicle is traveling, vibrations caused by the traveling act on the switch device 1. These vibrations act in the longitudinal direction (the vertical direction in FIG. 2 ) of the shaft 4. Therefore, if one end and the other end of the shaft 4 are supported only by the support holes 23, 24 of the side wall portions 221, 222, there is a possibility that the shaft 4 will move in a direction that causes it to fall out of the support holes 23, 24.
Furthermore, if the support force of the shaft 4 by the protrusion 241 of the support hole 24, i.e., the support by press-fitting, decreases due to deterioration over time or changes in the thermal environment surrounding the switch device 1, there is a possibility that the shaft 4 will move in a direction that causes it to fall out of the support holes 23, 24.

In this embodiment, a pair of support arms 25A, 25B provided inside the case 2 is used to restrict movement of the shaft 4 in the direction of the axis X.
The function of the pair of support arms 25A, 25B in the process of assembling the shaft 4 to the case 2 will now be described.

(A1) Assemble the operating knob 3 into the case 2, and position the connecting portions 34, 34 coaxially with the support holes 23, 24 provided in the side wall portions 221, 222 within the case 2. Then, insert the other end 4b of the shaft 4 into the support hole 23 in one of the side wall portions 221 (see Figure 7 (A)).

(A2) Within the case 2, a pair of support arms 25A, 25B are disposed opposite each other with the axis X therebetween. The engagement portions 251, 251 of the support arms 25A, 25B are disposed at a distance Da that is narrower than the outer diameter D4 of the shaft 4 (see FIG. 8A). Therefore, when the shaft 4 is further inserted into the case 2 from the state shown in FIG. 7A, the other end 4b of the shaft 4 is inserted between the pair of support arms 25A, 25B (see FIG. 7B).
At this time, since the support arms 25A, 25B are cantilevered by the support portion 211 on the case 2 side, the engaging portions 251, 251 of the support arms 25A, 25B are pushed by the shaft 4 and displaced in a direction away from the axis X. Note that the engaging portions 251, 251 located on both sides of the shaft 4 are displaced more on the side of the tips 25a, 25a than on the side of the connecting portions 252, 252 (see FIG. 8B).

As the shaft 4 continues to be inserted, the shaft 4 moves along the recess 211b of the support portion 211 toward the side wall portion 222, with the engaging portions 251, 251 of the support arms 25A, 25B contacting the outer periphery of the shaft 4 (see Figure 7C). At this time, the engaging portions 251, 251 located on both sides of the shaft 4 are displaced more on the side of the tips 25a, 25a than on the side of the connection portions 252, 252 (see Figure 8C).

As the shaft 4 continues to be inserted, the other end 4b of the shaft 4 passes through the insertion hole 341 of the connecting portion 34 and is then inserted into the support hole 24 of the side wall portion 222 (see FIG. 7D). As described above, the protrusion 241 is provided on the inner periphery of the support hole 24, so the area of the shaft 4 located within the support hole 24 is press-fit into the support hole 24.
Furthermore, when one end 4a and the other end 4b of the shaft 4 are inserted into the support holes 23 and 24 and reach the position where the recess 41 intersects with the center line C, the engaging portions 251 of the support arms 25A and 25B engage with the recess 41 due to a restoring force (see Figures 7(D) and 8(D)).
This restricts the movement of the shaft 4 in the direction of the axis X.

In this way, the support arms 25A and 25B are cantilevered by the support portion 211 of the case 2, allowing the longitudinal tip 25a, where the engagement portion 251 is located, to elastically displace in the radial direction of the shaft 4. Increasing the length of the connection portion 252 increases the overall length of the support arms 25A and 25B, thereby alleviating material stress associated with displacement and allowing for a larger displacement amount on the engagement portion 251 side. This allows the length L251 (see FIG. 6) of the engagement portion 251 to be set to the length required for engagement with the recess 41, while adjusting the length of the connection portion 252 to ensure the amount of displacement required for inserting the shaft 4 between the support arms 25A and 25B. Positioning the connection portion 252 using the opening 227 on the case 2 prevents the case 2 from becoming thick (thickness along the center line C in FIG. 6) and allows the support arms 25A and 25B to restrict movement of the shaft 4 along the axis X.

Here, in order to ensure an engagement allowance between the support arms 25A, 25B and the recess 41 of the shaft 4, it is necessary to displace the support arms 25A, 25B significantly when inserting the shaft 4 between the support arms 25A, 25B. However, the greater the amount of displacement, the greater the stress acting on the support arms 25A, 25B, which may result in the support arms 25A, 25B being unable to ensure the engagement allowance due to excessive stress. As described above, by increasing the overall length of the support arms 25A, 25B, the material stress acting on the support arms 25A, 25B can be alleviated, reducing the possibility of excessive stress.
Furthermore, a protrusion 241 is provided on the inner periphery of the support hole 24 into which the shaft 4 is finally inserted, and the shaft 4 is press-fitted into the support hole 24 at the end of the insertion of the shaft 4 into the case 2. This effectively prevents the insertability of the shaft 4 from becoming poor, and also restricts movement of the shaft 4 in the support hole 24 on the case 2 side.

9 is a diagram illustrating support arms 25A' and 25B' according to a modified example, in which only the support arm 25B' is shown for the sake of convenience.
In the above embodiment, the support arms 25A and 25B are bent at the connection portion J between the engaging portion 251 and the connecting portion 252 (see FIG. 6).
As shown in FIG. 9, the connecting portion J between the engaging portion 251 and the connecting portion 252 may be formed as supporting arms 25A' and 25B' that are curved in an arc shape.
This configuration also prevents the thickness of the case 2 from increasing, and allows the engaging portion 251 to restrict movement of the shaft 4 in the axial direction.
Furthermore, it is expected that the bearing strength of the support arms 25A' and 25B' will be improved when a shaft (not shown) is inserted between the support arms 25A' and 25B' from the left side in the figure.
The shape of the connection part J shown in Fig. 9 can be changed arbitrarily as long as it relieves the stress applied to the support arms 25A', 25B' when the shaft 4 is inserted between the support arms 25A', 25B'. The shape is not limited to the shape shown in Fig. 9 as long as it relieves the stress applied to the support arms 25A', 25B'.

Figure 10 is a diagram illustrating a shaft 4' according to a modified example. Figure 10(A) corresponds to a diagram in which the shaft 4 shown in Figure 5(B) is replaced with a shaft 4' according to a modified example. Figure 10(B) is a diagram showing the shaft 4' extracted from Figure 10(A).
In the above-described embodiment, the recess 41 is provided over the entire circumference in the circumferential direction around the axis X. As shown in Fig. 10, recesses 42, 42 may be provided having symmetrical flat surfaces 421, 421 sandwiching the axis X therebetween.
This also makes it possible to restrict the movement of the shaft 4 in the direction of the axis X.
Furthermore, the reduction in thickness of the shaft 4' at the portions where the recesses 42, 42 are provided is smaller than that of the shaft 4 described above, so that the durability of the shaft 4 can be expected to be improved.

As described above, the switch device 1 according to the embodiment has the following configuration.
(1) The switch device 1 includes a case 2 , a shaft 4 supported by the case 2 , and an operating knob 3 rotatably supported by the shaft 4 .
Case 2 is
a side wall portion 221 (first wall portion) and a side wall portion 222 (second wall portion) arranged at an interval in the longitudinal direction of the shaft 4;
a support hole 23 (first support hole) that is provided in the side wall portion 221 and that supports one end 4 a of the shaft 4 in the longitudinal direction;
a support hole 24 (second support hole) that is provided in the side wall portion 222 and supports the other end 4 b side of the shaft 4 in the longitudinal direction;
The support arms 25A and 25B are disposed on one side and the other side of the shaft 4 when viewed from the direction of the axis X (central axis direction) along the longitudinal direction of the shaft 4.
The support arms 25A and 25B are
an engaging portion 251 that is provided in a direction intersecting the axis X when viewed from the radial direction of the axis X and has a length that allows it to engage with the outer periphery of the shaft 4;
The engaging portion 251 is provided in a direction along the axis X, and has a connecting portion 252 that connects the engaging portion 251 and the support portion 111 on the case 2 side.

This configuration allows the overall length of the support arms 25A and 25B to be increased while ensuring sufficient engagement of the engaging portion 251 with the outer periphery of the shaft 4. This prevents the case 2 from becoming too large in the radial direction of the shaft 4 while ensuring sufficient displacement of the tips 25a and 25a of the support arms 25A and 25B. This prevents the case 2 from becoming too large while restricting longitudinal movement of the shaft 4.

(2) In (1) above,
When viewed from the direction of the axis X, the engaging portion 251 of the support arm 25A on one side of the shaft 4 and the engaging portion 251 of the support arm 25B on the other side of the shaft 4 are arranged on both sides of the shaft 4.
The shaft 4 has a recess 41 (groove) on the outer periphery thereof, into which the engaging portions 251, 251 engage.

With this configuration, the engagement portions 251, 251 of the support arms 25A, 25B engage with the recesses 41 of the shaft 4, more reliably restricting movement of the shaft 4 in the longitudinal direction (axis X direction).

(I) In (2) above,
The recess 41 is provided on the shaft 4 over the entire circumference around the axis X in the circumferential direction.

With this configuration, when assembling the shaft 4 to the case 2, the shaft 4 is inserted through the support hole 23 and penetrated through the connecting portions 34, 34, and then the shaft 4 is simply engaged with the support hole 24 having the protrusion 241 on its inner circumference, thereby engaging the engaging portions 251, 251 of the support arms 25A, 25B with the recess 41.
When assembling the shaft 4 to the case 2, there is no need to consider the angular position of the shaft 4 in the circumferential direction about the axis X, so the work of assembling the shaft 4 to the case 2 can be performed more easily.

(II) In the above (2), the recesses 442, 42 (grooves) having flat surfaces 421, 421 are provided on the side surfaces of the shaft 4' on one side and the other side with the axis X therebetween.
With this configuration, it is possible to provide a shaft 4' having higher rigidity and strength than a shaft 4 in which the recesses 41 are provided around the entire circumference in the circumferential direction. This makes it possible to reduce the outer diameter of the shaft 4, thereby preventing the case 2 from becoming larger in the radial direction of the axis X.

(3) In any one of the above (1), (2), (I), and (II),
When viewed from the direction of the axis X, a protrusion 241 is provided on the inner periphery of at least one of the support holes 23 and 24.

With this configuration, for example, the shaft 4 is press-fitted into the support hole 24 in which the protrusion 241 is provided, so that movement of the shaft 4 in the longitudinal direction (axis X direction) can be more reliably restricted.
Furthermore, at the end of the insertion of the shaft 4 into the case 2, the shaft 4 is press-fitted into the support hole 24. This effectively prevents the insertability of the shaft 4 from becoming poor, and also restricts the movement of the shaft 4 in the support hole 24 on the case 2 side.

(III) In the above (3),
The basic shape of the support holes 23, 24 as viewed in the direction of the axis X is a circle with an inner diameter that matches the outer diameter of the shaft 4 as viewed in the direction of the axis X.
When viewed from the direction of the axis X, the protrusion 241 has an arch shape with a linear side surface 241 a positioned on the side of the axis X. The side surface 241 a of the protrusion 241 is parallel to the tangent line L of the support holes 23, 24 and is positioned closer to the axis X than the inner peripheries of the support holes 23, 24.
At least three protrusions 241 are provided at equal intervals in the circumferential direction around the axis X.

This configuration allows the shaft 4 to be supported evenly.

(4) In any one of the above (1), (2), (3), (I), (II), and (III),
When viewed from the radial direction of the axis X, the connection portion 252 of the support arms 25A, 25B extends radially outward of the shaft 4 in the longitudinal direction of the shaft 4.
One end of the connection portion 252 in the longitudinal direction is connected to the support portion 211 on the case 2 side.
The other end of the connecting portion 252 in the longitudinal direction is connected to one end of the engaging portion 251 in the longitudinal direction.
When viewed from the radial direction of the axis X, the support arms 25A and 25B are bent at a connection portion J between the connection portion 252 and the engagement portion 251 as a boundary.

With this configuration, the support arms 25A, 25B are cantilevered by the support portion 211 of the case 2, and the longitudinal tip 25a side where the engagement portion 251 is located is elastically displaceable in the radial direction of the shaft 4. By increasing the length of the connection portion 252, the material stress associated with displacement is alleviated, allowing for a larger amount of displacement on the engagement portion 251 side. The amount of displacement of the engagement portion 251 can be ensured while limiting the length of the engagement portion 251 in the radial direction of the shaft 4.

(5) In any one of the above (1), (2), (3), (I), (II), and (III),
When viewed in the radial direction of the axis X, the connection portion 252 of the support arms 25A′, 25B′ extends radially outward of the shaft 4 in the longitudinal direction of the shaft 4.
One end of the connection portion 252 in the longitudinal direction is connected to the support portion 211 on the case 2 side.
The other end of the connecting portion 252 in the longitudinal direction is connected to one end of the engaging portion 251 in the longitudinal direction.
When viewed in the radial direction of the axis X, the support arms 25A' and 25B' are curved at the connection point between the connection portion 252 and the engagement portion 251.

With this configuration, support arms 25A', 25B' are cantilevered by case 2, and the longitudinal tip 25a side where engaging portion 251 is located can be elastically displaced in the radial direction of shaft 4. By increasing the length of connecting portion 252, the amount of displacement on the engaging portion 251 side can be increased. The amount of displacement of engaging portion 251 can be ensured while reducing the length of engaging portion 251 in the radial direction of shaft 4. Furthermore, by making the shape of engaging portion 251 side of support arms 25A', 25B' curved, stress concentration at the boundary between engaging portion 251 and connecting portion 252 due to stress when shaft 4 is inserted between support arms 25A', 25B' can be reduced.
The shape of the engaging portion 251 side of the support arms 25A and 25B can be changed arbitrarily for the purpose of alleviating stress, etc.

(IV) In the above (5),
When viewed from the engaging portion 251, the connecting portion 252 extends in the insertion direction of the shaft 4 (toward the side wall portion 222).

With this configuration, the boundary between the engagement portion 251 and the connection portion 252 is located on the side wall portion 222 side, making it less likely for the engagement portion 251 to collapse due to stress acting on the support arms 25A and 25B when the shaft 4 is inserted between the support arms 25A and 25B.

(6) In any one of the above (1) to (5), (I) to (IV),
The bottom wall 21 of the case 2 is provided with an opening 227 capable of accommodating the connection part 252 .
When viewed from the radial direction of the axis X, the connection portion 252 is provided in a positional relationship where it overlaps with the bottom wall portion 21 .

With this configuration, the connection portion 252 can be provided by utilizing the thickness of the bottom wall portion 21. In order to increase the overall length of the support arms 25A and 25B, there is no need to make the connection portion 252 bulge outward from the case 2. As a result, there is no need to increase the size of the case 2 in the thickness direction when providing the support arms 25A and 25B.

The present invention can also be specified as a support structure for a shaft 4 supported by a case 2.
(7) Case 2 is
a side wall portion 221 (first wall portion) and a side wall portion 222 (second wall portion) arranged at an interval in the longitudinal direction of the shaft 4;
a support hole 23 (first support hole) that is provided in the side wall portion 221 and that supports one end 4 a of the shaft 4 in the longitudinal direction;
a support hole 24 (second support hole) that is provided in the side wall portion 222 and supports the other end 4 b side of the shaft 4 in the longitudinal direction;
The support arms 25A and 25B are disposed on one side and the other side of the shaft 4 when viewed from the direction of the axis X (central axis direction) along the longitudinal direction of the shaft 4.
The support arms 25A and 25B are
an engaging portion 251 that is provided in a direction intersecting the axis X when viewed from the radial direction of the axis X and has a length that allows it to engage with the outer periphery of the shaft 4;
The engaging portion 251 is provided in a direction along the axis X, and has a connecting portion 252 that connects the engaging portion 251 and the support portion 111 on the case 2 side.

This configuration allows the overall length of the support arms 25A and 25B to be increased while ensuring sufficient engagement of the engaging portion 251 with the outer periphery of the shaft 4. This prevents the case 2 from becoming too large in the radial direction of the shaft 4 while ensuring sufficient displacement of the tips 25a and 25a of the support arms 25A and 25B. This prevents the case 2 from becoming too large while restricting longitudinal movement of the shaft 4.

The above describes embodiments and variations of the present invention, but the present invention is not limited to these and can be modified as appropriate within the scope of the technical concept of the invention.

1: Switch device 2: Case 21: Bottom wall 211: Support portion 211b: Recess 22: Peripheral wall portions 221 to 224: Side wall portion 225: Rib 226: Rib 227: Openings 23, 24: Support hole 231: Protrusions 25A, 25A', 25B, 25B': Support arm 25a: Tip 251: Engagement portion 252: Connection portion 3: Operation knob 4, 4': Shaft 40: Base 41, 41', 42: Recess 421: Flat surface C: Center line J: Connection portion X: Axis (center axis)

Claims (7)

Case and
a shaft supported by the case;
an operation knob rotatably supported by the shaft,
The case is
a first wall portion and a second wall portion spaced apart in a longitudinal direction of the shaft;
a first support hole provided in the first wall portion and supporting one end side of the shaft in the longitudinal direction;
a second support hole provided in the second wall portion and supporting the other end of the shaft in the longitudinal direction;
support arms disposed on one side and the other side of the shaft as viewed from a central axis direction along the longitudinal direction of the shaft,
The support arm is
an engaging portion provided in a direction intersecting the central axis when viewed from the one side in the radial direction of the central axis and having a length capable of engaging with an outer periphery of the shaft;
a connecting portion that is oriented along the central axis and connects the engaging portion and the case; In claim 1,
When viewed from the central axis direction, the engaging portion of the support arm on one side of the shaft and the engaging portion of the support arm on the other side of the shaft are arranged on both sides sandwiching the shaft therebetween,
A switch device, wherein a groove with which the engaging portion engages is provided on the outer periphery of the shaft. In claim 1,
A switch device, wherein a protrusion is provided on an inner periphery of at least one of the first support hole and the second support hole when viewed from the central axis direction. In any one of claims 1 to 3,
When viewed from the one side in the radial direction of the central axis, the connection portion of the support arm extends radially outward of the shaft in a longitudinal direction of the shaft,
One end of the connection portion in the longitudinal direction is connected to the case,
the other end of the connecting portion in the longitudinal direction is connected to the engaging portion,
When viewed from the one side in the radial direction of the central axis, the support arm is bent at a connection point between the connection portion and the engagement portion. In any one of claims 1 to 3,
When viewed from the one side in the radial direction of the central axis, the connection portion of the support arm extends radially outward of the shaft in a longitudinal direction of the shaft,
One end of the connection portion in the longitudinal direction is connected to the case,
the other end of the connecting portion in the longitudinal direction is connected to the engaging portion,
When viewed from the one side in the radial direction of the central axis, the support arm is curved around a connection point between the connection portion and the engagement portion. In any one of claims 1 to 3,
an opening capable of accommodating the connection portion is provided in a bottom wall portion of the case;
When viewed from the side of the case, the connection portion is positioned so as to overlap the bottom wall portion. A support structure for a shaft supported by a case,
The case is
a first wall portion and a second wall portion spaced apart in a longitudinal direction of the shaft;
a first support hole provided in the first wall portion and supporting one end side of the shaft in the longitudinal direction;
a second support hole provided in the second wall portion and supporting the other end of the shaft in the longitudinal direction;
support arms disposed on one side and the other side of the shaft as viewed from a central axis direction along the longitudinal direction of the shaft,
The support arm is
an engaging portion provided in a direction intersecting the central axis when viewed from the one side in the radial direction of the central axis and having a length capable of engaging with an outer periphery of the shaft;
A shaft support structure having a connection portion that is oriented along the central axis and connects the engagement portion and the case.