JP7437471B1 - Mechanism for attaching the rotating knob to the rotating shaft - Google Patents

Abstract

An object of the present invention is to provide a mechanism for attaching a rotating knob to a rotating shaft, in which a recessed portion of the rotating shaft and a convex portion of the rotating knob are fitted to prevent the knob from coming off, which deteriorates with repeated attachment and detachment. SOLUTION: A through hole 24 perpendicularly intersecting the central axis is bored in a rotation shaft 21, and a locking recess 25 is formed in one opening. The inner cylindrical portion 14 of the rotation knob 11 has axial slits formed on both sides of the region facing the locking recess 25 when fitted onto the rotation shaft 21, so that a cantilever-shaped elastic locking portion 15 is formed. A locking protrusion 17 that fits into the locking recess 25 is provided in the opposing region, and a long hole 18 is formed in the outer cylindrical portion 12 of the rotary knob 11 at a position opposite to the through hole 24. put. A stable locking function is obtained by the locking relationship in which the locking protrusion 17 is fitted into the locking recess 25, and by inserting the pin rod 55 from the elongated hole 18 through the through hole 24, the locking protrusion in the locking recess 25 is secured. 17, release the locking relationship, and pull out the rotation knob 11 from the rotation shaft 21. [Selection diagram] Figure 3

Description

The present invention relates to a mechanism for detachably attaching a rotating knob to a rotating shaft of an electronic component protruding from a housing, front panel, etc. of a telecommunications equipment.

Various configurations have been used to attach rotating knobs for operation on the rotating shaft of electronic components such as volume resistors and rotary encoders. A notch called a D-cut is formed in the shaft so that the shaft cross section is D-shaped, and the hole formed on the rotation knob side is fitted into the D-cut section on the rotation shaft side. , a method is often adopted in which the torque acting on the rotating knob is reliably transmitted to the rotating shaft.

In that case, in order to prevent the rotation knob from coming off, the fitting conditions are controlled by the fit tolerance, and the D-cut section of the rotation shaft is press-fitted into the hole on the rotation knob side that is made of a resin material by injection molding. In most cases, the locking function is achieved only by the frictional force caused by pressure welding, but a more reliable locking function can be obtained by creating a locking relationship between the protrusion and the recess on the close contact surface between the rotating shaft and the rotating knob. In many cases, this is the case.

For example, in the following Patent Document 1, as shown in FIG. 10, in the fitting structure of the rotation knob 101 and the rotation shaft 102, the rotation shaft 102 has a D cut and a groove 103 at a predetermined position in the axial direction. On the other hand, a protrusion 105 is provided on the inner peripheral surface of the insertion hole 104 of the rotation shaft 102 in the rotation knob 101 at a predetermined position corresponding to the groove 103, so that the rotation knob 101 can be connected to the rotation shaft. 102 is disclosed, the groove portion 103 and the convex portion 105 are configured to fit together.

Furthermore, Patent Document 2 listed below discloses a structure for attaching a rotating knob to a rotating shaft as shown in FIG. 11 as a prior art that is an object of improvement in the invention of the same document.
In this structure, a resin adapter ("spacer" in the above document) 203 is interposed between the rotation shaft 201 and the rotation knob 202, and the adapter 203 is inserted around the D-cut portion 204 of the rotation shaft 201. It is fitted externally into the rotary knob 202 and internally fitted into the hole 205 of the rotation knob 202.

A recess 206 is formed on the outer peripheral surface of the rotating shaft 201 at a predetermined position in the axial direction other than the D-cut portion 204, and a claw 207 formed on the outer fitting portion of the adapter 203 is connected to the recess 206. They are fitted, and a locking relationship in the fitted state constitutes a mechanism for preventing the adapter 203 from coming off from the rotation shaft 201.
Furthermore, regarding the relationship between the rotating knob 202 and the adapter 203, a protrusion 208 is formed on the fitting surface on the adapter 203 side, while a groove 209 is formed on the fitting surface on the rotating knob 202 side. The locking relationship in their fitted state constitutes a function to prevent the rotation knob 202 from coming off from the adapter 203.

The invention of Patent Document 2 below relates to an improvement to the basic structure, and by using a separate metal plate-like member for interposition, the rotation knob 202 can be repeatedly attached and detached from the rotation shaft 201. This is a proposal to maintain a strong retaining force without causing the member to be scraped.

Utility Model Publication No. 5-79615 Japanese Patent Application Publication No. 2006-343794 (Figure 5, Figure 6)

In order to prevent the rotary knob from falling off the rotation shaft, relying only on the pressure friction force based on press-fitting lacks stability and there is always a possibility that the rotary knob will fall off, as described in Patent Documents 1 and 2. It goes without saying that it is desirable to provide a highly reliable locking function with a suitable locking means.
However, when an electronic device breaks down, it is often necessary to remove the built-in electronic circuit board, but the rotation axes of the volume, rotary encoder, etc. need to be protruded outside through the hole in the casing. Since a knob is attached, the rotating knob will have to be removed from the rotating shaft in any case.

In that case, the rotation knob must be strongly pulled in the axial direction to forcibly release the locking relationship with the rotation shaft, but the locking relationship is due to the uneven fitting of the mating surface between the shaft and the cylinder. For example, in the configurations shown in FIGS. 10 and 11, the convex portions 105 and claws 207 made of resin material are often strongly rubbed and scraped off by the corners of the grooves 103 and concave portions 206. When it is reattached, the retaining function is often lost or has deteriorated to the point where it is no longer fully effective.
As mentioned above, the invention of Patent Document 2 itself is originally a measure against such problems, but it has a structure in which a metal plate-like member is separately interposed on the outer circumferential side of the claw 207 of the adapter 203. However, there is a problem that the number of parts increases and the time and effort required to attach the rotary knob 202 increases.

Therefore, in view of the problems of the prior art described above, the present invention can always establish a stable locking relationship between the rotating shaft and the rotating knob, and the rotating knob can be removed very easily using a pin. It is an object of the present invention to provide a mechanism for attaching a rotating knob to a rotating shaft, which can be operated without deteriorating the locking relationship.

In the present invention, a D-cut section of a certain length is formed in the axial direction from the tip of the rotating shaft, and the rotating knob is made of resin and has a basic shape of a cap with a bottom. An inner cylindrical part is formed upright on the top plate part inside the outer cylindrical part, and the inner cylindrical part of the rotary knob is fitted into the D-cut section of the rotary shaft. In the attachment mechanism to the rotation shaft, the rotation shaft is provided with a through hole that is substantially perpendicular to the central axis and passes through the same central axis at a position rearward from the D-cut section, and a through hole that is substantially perpendicular to the central axis and passes through the same central axis. A locking recess is formed on one opening side of the through hole that is outside the range of the central angle formed by the D-cut forming portion, and the locking recess includes the opening and continues for a predetermined length toward the axially distal end side. The rotation knob is provided with an axial direction along both sides in the circumferential direction of a region of the inner cylinder part facing the locking recess of the rotation shaft in an attached state in which the inner cylinder part is tightly fitted onto the rotation shaft. A cantilever-like portion is formed by forming a slit in the hem, and an elastic locking portion is formed in the area of the cantilever-like portion with a locking protrusion that fits inside the locking recess of the rotation shaft. and a width equal to or larger than the hole diameter of the through hole at a position of the outer cylindrical portion facing the opening of the through hole, which is the side opposite to the side where the locking recess is formed in the rotation shaft in the attached state. The present invention relates to a mechanism for attaching a rotating knob to a rotating shaft, characterized in that a long hole extending toward a side opposite to the top plate portion is bored therein.

In the present invention, by fitting the inner cylindrical portion of the rotating knob onto the D-cut section of the rotating shaft, the locking protrusion of the elastic locking portion fits internally into the locking recess on the rotating shaft side. However, in this fitted state, even if a pulling force is applied in the axial direction of the rotating knob, the locking relationship between the locking protrusion and the locking recess cannot be released, and the rotating knob cannot be pulled out from the rotating shaft. Can not.
On the other hand, when a pin rod with a diameter smaller than that hole is inserted into the through hole of the rotation shaft from the elongated hole of the outer cylinder of the rotation knob, the elastic locking part fitted inside the locking recess of the rotation shaft will close. It hits the area where the locking protrusion is formed, but when pressed further with the pin rod, the elastic locking part easily bends outward because it is configured as a cantilever, and the locking protrusion locks the rotation shaft. The locking relationship is released by coming out of the fitted state in the recess.
Therefore, if you pull the rotation knob slightly in the pulling direction in this state, the rotation knob will move easily, and the locking protrusion of the rotation knob will be removed from the area of the locking recess of the rotation shaft and positioned on the outer circumferential surface. However, in this state, even if the pin rod is pulled out, the locking protrusion does not return to the locking recess of the rotating shaft, but comes into contact with the outer circumferential surface and becomes slidable in the axial direction. In that case, the long hole in the outer cylinder is formed as a long hole instead of a circular hole so that the pin rod does not come into contact with the initial slight pullout of the rotating knob and impede its movement. .
Thereafter, the rotating knob can be pulled out from the rotating shaft with a slight pulling force.
During this series of operations, the locking protrusion of the rotation knob is pushed in the direction perpendicular to the cantilevered elastic locking part at the tip of the elastic locking part, and is pushed out of the locking recess of the rotation shaft. Even if the rotary knob is repeatedly attached and detached many times, the locking mechanism will not deteriorate.

In the present invention, the "region of the inner cylindrical portion facing the locking recess" refers to the area where the inner cylindrical portion has a cylindrical portion and a partial extension from the end surface of the cylindrical portion, and the extended portion is This includes a case where the area corresponds to the above area and a case where the area is located on the inner circumferential surface of the inner cylinder part.
Therefore, in the elastic locking portion of the rotation knob, the inner cylindrical portion has a cylindrical portion and a partial extension from an end surface of the cylindrical portion, and the extended portion is the rotation axis of the inner cylindrical portion. The locking protrusion may be formed in the same area, and the locking protrusion may be formed in the same area.

Further, in the present invention, the elastic locking portion of the rotation knob is located closer to the top plate than at a position facing the through hole in a region where the locking protrusion faces the locking recess of the rotation shaft. It is preferable that it be formed only in the side area.
The locking relationship between the locking recess on the rotation shaft side and the locking protrusion of the elastic locking part on the rotation knob side is such that the surface of the locking protrusion on the top plate side is caught by the surface on the tip side of the locking recess. The locking protrusion does not need to fill the entire locking recess and fit into the locking recess, but rather should be formed only in the area closer to the top plate than the position facing the through hole. However, if the other areas are made into parts where the plate thickness of the beam portion of the elastic locking portion is extended, it will be easier to press the pin rod when releasing the lock.

Further, in the present invention, the top plate portion of the rotary knob has a projected position when the locking protrusion of the elastic locking portion on the top plate portion is projected in the axial direction. It is desirable that a planar hole is bored.
The resin rotating knob is manufactured by injection molding, but the locking protrusion of the elastic locking part cannot be molded without undercutting, and the hole in the top plate is unavoidably formed as a hole for the nest. be done.
If the slits formed on both sides of the elastic locking part are not formed all the way to the top plate, this hole in the top plate is used as the rotation axis when the rotation knob is attached to and removed from the rotation axis. It serves as a ventilation hole between the inside of the inner cylinder and the outside, and serves to prevent any hindrance to attachment/detachment operations.

Further, in the present invention, it is preferable that a corner of the opening of the rotation shaft in the through hole on the opposite side from the side where the locking recess is formed is chamfered.
This is because the tip of the pin rod can be guided more easily when the pin rod is inserted into the through hole of the rotation shaft through the elongated hole of the outer cylindrical portion of the rotation knob.

The mechanism for attaching the rotary knob to the rotary shaft of the present invention can achieve a stable retaining function, and also allows the rotary knob to be attached to and removed from the rotary shaft without degrading the locking mechanism for retaining the rotary knob. , can be performed reasonably with extremely simple operations.
Note that the pin rod used when removing the rotating knob can be replaced with a stretched wire such as a gem clip, and there is no need to prepare a special item.

FIG. 2 is an axial sectional view of a main part according to an embodiment of the present invention (a state in which a rotating knob is attached to a rotating shaft). FIG. 3 is an axial sectional view of essential parts showing a first step in removing the rotation knob from the rotation shaft in the embodiment. FIG. 7 is an axial cross-sectional view of essential parts showing a second step when removing the rotation knob from the rotation shaft in the embodiment. FIG. 7 is an axial sectional view of essential parts showing a third step when removing the rotation knob from the rotation shaft in the embodiment. It is an axial sectional view of the principal part showing the fourth floor when removing a rotation knob from a rotation shaft in an embodiment. They are a front view (partial sectional view) (A), a top view (B), a left side view (C), and a right side view (D) of the rotation shaft. Axial sectional view (A), left side view (B), bottom view (C), top view (D), and XX sectional view shown in the axial sectional view (A) of the rotary knob according to Example A (E) and YY cross-sectional view (F). Axial sectional view (A), left side view (B), bottom view (C), top view (D), and XX cross-sectional view shown in the axial sectional view (A) of the rotary knob according to Example b (E) and YY cross-sectional view (F). Axial cross-sectional view (A) of the rotary knob according to Example A and an axial cross-section of the rotary knob according to Example B, in which the slit constituting the elastic locking part is not formed over the entire length of the inner cylinder part It is figure (B). FIG. 2 is an axial sectional view of a main part of a mechanism for attaching a rotating knob to a rotating shaft according to the prior art (Patent Document 1). FIG. 2 is an axial sectional view of a main part of a mechanism for attaching a rotating knob to a rotating shaft according to the prior art (Patent Document 2).

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a mechanism for attaching a rotating knob to a rotating shaft according to the present invention will be described in detail with reference to the drawings.
First, FIG. 1 shows a state in which the rotating knob 11 is attached to the rotating shaft 21. As shown in FIG.
The rotating shaft 21 in this case relates to the volume 22 which is an electronic component, and the volume 22 itself is fixed by tightening its bearing part to the sub-panel 51 with a nut 52, and the rotating shaft 21 is connected to the volume 22. The mounting portion of the moving knob 11 projects forward through a hole 54 formed in the front panel 53.

The details of this rotation shaft 21 are shown in FIG. 6, and a certain section is cut out from the tip to form a D-cut section 23 that has a flat surface parallel to the central axis. At a further rear position, a through hole 24 is bored in a direction substantially perpendicular to the central axis and passing through the same central axis.
Further, in this embodiment, the direction in which the through hole 24 is formed is perpendicular to the flat surface of the D-cut section 23, and the two openings are located at the rear position and the circumference of the D-cut section 23. Although the opening is located on the opposite side in the direction, a locking recess 25 is formed in the opening at the latter position, which includes the opening and continues for a predetermined length toward the distal end in the axial direction.

The planar shape of the locking recess 25 in this embodiment is an elongated hole with arcuate ends at both ends in consideration of ease of machining, but the shape is not limited to this.
In addition, the corners other than the D-cut portion at the tip of the rotating shaft 21 are chamfered so that insertion into the rotating knob 11 side is smooth, and the side where the locking recess 25 is formed is chamfered. The corner of the opening of the through hole 24 on the opposite side is also chamfered to facilitate insertion of a pin rod, which will be described later.

On the other hand, details of embodiment a of the rotary knob 11 are shown in FIG. 7, and it has a basic shape like a bottomed cap like a normal rotary knob, but the outer cylindrical part 12 and the top plate part are formed by injection molding. 13 and an inner cylinder part 14 are integrally constructed of a resin product.
Here, the inner cylinder part 14 is formed upright on the top plate part 13 inside the outer cylinder part 12, and is adapted to closely fit into the D-cut section 23 of the rotation shaft 21.

A cantilever-shaped elastic locking portion 15 is formed in this inner cylinder portion 14.
That is, as shown in FIG. 1, in the installed state in which the inner cylindrical portion 14 is tightly fitted onto the D-cut section 23 of the rotation shaft 21, the inner cylinder portion 14 is inserted along both sides in the circumferential direction of the area facing the locking recess 25 on the rotation shaft 21 side. As shown in FIG. 7(E), slits 16a and 16b are formed in the axial direction, thereby forming a cantilever beam in a part of the inner cylinder part 14 with the top plate part 13 as a fixed end. However, the elastic locking portion 15 is formed with a locking protrusion 17 that fits inside the locking recess 25 on the rotating shaft 21 side in the opposing region of the cantilever.

However, in this embodiment, the locking protrusion 17 of the elastic locking part 15 is not shaped to fit into the entire locking recess 25 on the rotation shaft 21 side, and as shown in FIGS. 1 and 7(A). As shown in FIG. 2, it is formed only in a region closer to the top plate portion 13 than the position facing the through hole 24 on the rotating shaft 21 side in the above-mentioned attached state.

Further, the outer cylindrical portion 12 of the rotation knob 11 has a position opposite to the opening of the through hole 24 on the opposite side of the rotation shaft 21 from the side where the locking recess 25 is formed in the attached state shown in FIG. A long hole 18 is bored in the hole.
This elongated hole 18 has a width slightly wider than the diameter of the through hole 24 of the rotation shaft 21, and has a hole shape that extends slightly from the above-mentioned position toward the opposite side of the top plate portion 13.

Furthermore, the projection position of the locking protrusion 17 of the elastic locking part 15 on the top plate part 13 is projected onto the top plate part 13 of the rotary knob 11 in the axial direction. Hole 19 is drilled.
This is because the rotary knob 11 is manufactured by injection molding, and is a hole for pulling out the nest during an undercut process to form the locking protrusion 17 on the elastic locking portion 15.

Next, a procedure for removing the rotation knob 11 from the rotation shaft 21 will be explained using FIGS. 1 to 5.
First, in the state shown in FIG. 1, that is, the state in which the rotary knob 11 is attached to the rotary shaft 21, the D-cut section 23 of the rotary shaft 21 is in close contact with the inner cylindrical portion 14 of the rotary knob 11. Because it is internally fitted, the rotational torque that is applied when the rotation knob 11 is operated is directly transmitted to the rotation shaft 21. However, when a force in the pulling direction is applied to the rotation knob 11, Since the locking protrusion 17 of the elastic locking portion 15 is caught on the inner wall surface on the distal end side of the locking recess 25 of the rotation shaft 21, it cannot be pulled out.

When pulling out the rotation knob 11, as shown in FIG. 2, a pin rod 55 having a diameter smaller than the diameter of the through hole 24 of the rotation shaft 21 is used.
Insert the pin rod 55 into the through hole 24 of the rotation shaft 21 through the long hole 18 of the outer cylindrical portion 12 of the rotation knob 11 and feed it further, so that its tip passes through the through hole 24 and reaches the locking recess 25 side. However, the locking protrusion 17 of the elastic locking part 15 is fitted into the shaft end side of the locking recess 25, and the tip of the pin rod 55 extends beyond the locking protrusion 17 of the elastic locking part 15. It hits the tip and pushes that part outward.
Then, the elastic locking portion 15, which is a cantilever beam, bends under the load at its tip, but along with the bending, the locking protrusion 17 of the elastic locking portion 15 locks the rotation shaft 21. It moves outward from the recess 25 and the locking relationship is released.

Then, when a pulling force is applied to the rotation knob 11 in the released state of the locking relationship, as shown in FIG. The rotary knob 11 moves in the drawing direction by the axial length of the elongated hole 18 without receiving almost any resistance.
That is, when the tip of the elastic locking portion 15 is pushed outward by the pin rod 55 and the locking protrusion 17 is removed from the locking recess 25 of the rotation shaft 21, the rotation knob 11 is moved in the pulling direction. While the tip of the pin rod 55 and the tip of the elastic locking part 15 are sliding, as shown in FIG. Move to a position facing the
Therefore, the length in the axial direction of the elongated hole 18 of the rotary knob 11 only needs to be a length corresponding to a small moving distance.

When the rotation knob 11 is pulled out to the state shown in FIG. 3, even if the pin rod 55 is removed, the locking protrusion 17 will restore the elastic locking portion 15 as a cantilever, as shown in FIG. It simply comes into contact with the outer peripheral surface of the rotating shaft 21 due to force.
Therefore, as shown in FIG. 5, when the rotation knob 11 is further pulled out, the locking protrusion 17 of the elastic locking part 15 slides on the outer circumferential surface of the rotation shaft 21, and the inner cylinder part 14 moves onto the rotation shaft 21. The rotation knob 11 is finally removed from the rotation shaft 21.
Also, in the withdrawal procedure, since the locking relationship is released, there is no resistance force other than the sliding friction force between the locking protrusion 17 of the elastic locking portion 15 and the outer circumferential surface of the rotation shaft 21. The rotation knob 11 can be removed without any problems.

On the other hand, when attaching the rotary knob 11 to the rotary shaft 21, press the locking protrusion 17 of the elastic locking portion 15 of the rotary knob 11 outward with the tip of the rotary shaft 21. 15, fit the open end of the inner cylindrical portion 14 of the rotary knob 11 onto the tip of the rotary shaft 21, and then press the rotary knob 11 in the axial direction, resulting in the state shown in FIG. As shown (however, the direction of the arrow is in the opposite direction), the D-cut section 23 of the rotation shaft 21 is inserted into the inner cylinder part 14 of the rotation knob 11, and the locking protrusion 17 of the elastic locking part 15 is inserted. The attachment work is completed by resiliently fitting into the locking recess 25 of the rotating shaft 21.

Therefore, according to the mechanism for attaching the rotating knob 11 to the rotating shaft 21 according to this embodiment, the rotating knob 11 can be rotated by a simple procedure without deteriorating the locking means for preventing the rotating knob 11 from coming off. The knob 11 can be attached to and detached from the rotating shaft 21.

By the way, the structure of the inner cylinder part 14 of the rotating knob 11 according to the embodiment a of FIG. 7 may be changed to the structure of the inner cylinder part 41 as in the embodiment b of FIG. 8.
However, in FIG. 8, the same components as the rotating knob 11 in FIG. 7 are given the same reference numerals.
As is clear from FIGS. 8A, 8C, 8E, and 8F, in the inner cylindrical portion 41 of the rotation knob 11 according to this embodiment b, the D-cut section 23 of the rotation shaft 21 The feature is that only the part that is in close contact with the rotating shaft 21 is short in the axial direction, and the part that is in close contact with the other outer peripheral surface of the rotation shaft 21 is the same length as the elastic locking part 15. The slits 42a and 42b on both sides of the elastic locking portion 15 also have the same length as the elastic locking portion 15.

In addition, in each of the rotating knobs of Examples a and b, the slits (16a, 16b) (42a, 42b) on both sides of the elastic locking portion 15 reach the inner surface of the top plate portion 13, but the elastic locking portion If you want to increase the spring constant of the locking protrusion 17 portion as a cantilever of the portion 15 to force the locking protrusion 17 to fit more firmly into the locking recess 25 on the rotation shaft 21 side, use a slit. It is effective to shorten the span of the elastic locking portion 15 by shortening (16a, 16b) (42a, 42b).
That is, the slits (45a, 45b) (46a, 46b) of the rotating knob 11 are formed as shown in FIG. 9(A) in the case of the embodiment a, and as shown in FIG. 9(B) in the case of the embodiment b. By not forming it up to the inner surface of the top plate part 13 and forming it halfway up the inner cylinder parts 14, 41, the spring constant at the locking protrusion 17 portion of the elastic locking parts 47, 48 can be increased.
In this way, the method of shortening the span of the elastic locking part 15 as a cantilever is effective when the Young's modulus of the resin that constitutes the rotary knob 11 is low, or when the thickness of the inner cylindrical parts 14 and 41 is increased. This is the simplest and most effective way to deal with such situations.

In the case where the slits (45a, 45b) (46a, 46b) are not formed up to the inner surface of the top plate part 13 as shown in FIG. 9, the holes 19 formed in the top plate part 13 function effectively.
When the rotating knob 11 is attached to or removed from the rotating shaft 21, the space surrounded by the tip surface of the rotating shaft 21, the inner peripheral surface of the inner cylinder parts 14, 41, and the inner surface of the top plate part 13 is outside. However, if the slits (16a, 16b) (42a, 42b) reach the inner surface of the top plate part 13 as shown in Figures 7 and 8, then those slits (16a, 16b) ) (42a, 42b) is ensured, so there is no problem.

However, in the case of the rotary knob 11 in which the slits (45a, 45b) (46a, 46b) do not reach the inner surface of the top plate part 13 as shown in FIG. 9, the hole 19 is not formed in the top plate part 13. Otherwise, the rotating shaft 21 cannot be inserted closer to the top plate portion 13 than the section in the inner cylinder portions 14, 41 of the rotating knob 11 where the slits (45a, 45b) (46a, 46b) are formed.
In other words, when the hole 19 of the top plate part 13 is such that the rotation knob 11 has slits (45a, 45b) (46a, 46b) that do not reach the inner surface of the top plate part 13 as shown in FIG. In addition, it is effective in the sense that it enables attachment and detachment to the rotation shaft 21.

The present invention can be applied to a mechanism for detachably attaching a rotating knob to a rotating shaft of an electronic component.

11...Rotating knob, 12...Outer cylinder part, 13...Top plate part, 14...Inner cylinder part, 15...Elastic locking part, 16a, 16b...Slit, 17...Latching protrusion, 18...Long hole, 19... Hole, 21...Rotation axis, 22...Volume, 23...D cut section, 24...Through hole, 25...Locking recess, 41...Inner cylinder part, 42a, 42b...Slit, 45a, 45b...Slit, 46a, 46b ...slit, 47...elastic locking part, 48...elastic locking part, 51...sub panel, 52...nut, 53...front panel, 54...hole, 55...pin rod, 101...rotation knob, 102...rotation shaft , 103...Groove, 104...Insertion hole, 105...Protrusion, 201...Rotation shaft, 202...Rotation knob, 203...Adapter, 204...D cut part, 205...Hole, 206...Recess, 207...Claw, 208 ...convex ridges, 209...grooves.

Claims (5)

The rotation shaft has a D-cut section of a certain length in the axial direction from its tip, while the rotation knob is made of resin and has a basic shape of a cap with a bottom, and the outer cylinder part of the rotation knob is made of resin. An inner cylindrical part is formed to stand up on the top plate part on the inside, and the inner cylindrical part of the rotary knob is fitted into the D-cut section of the rotary shaft. In the mounting mechanism of
The rotation shaft is provided with a through hole that is substantially perpendicular to the central axis and passes through the same central axis at a position rearward of the D-cut section, and has a central angle formed by the D-cut forming portion in the circumferential direction. A locking recess that includes the opening and continues for a predetermined length toward the tip end in the axial direction is formed on one opening side of the through hole that is outside the range,
The rotation knob includes a shaft extending along both sides in the circumferential direction of a region of the inner cylinder portion facing the locking recess of the rotation shaft in an attached state in which the inner cylinder portion is tightly fitted onto the rotation shaft. an elastic locking portion that forms a cantilever-like portion by forming a slit in the direction, and has a locking protrusion that fits inside the locking recess of the rotation shaft in the region of the cantilever-like portion; and a hole having a diameter larger than or equal to the diameter of the through hole, at a position of the outer cylindrical portion facing the opening of the through hole, which is the side opposite to the side where the locking recess is formed on the rotation shaft in the attached state. A mechanism for attaching a rotary knob to a rotary shaft, characterized in that a long hole extending in width to a side opposite to the top plate portion is bored. The elastic locking portion of the rotary knob is such that the inner cylindrical portion has a cylindrical portion and a partial extension portion from an end surface of the cylindrical portion, and the extended portion extends from the end surface of the rotation shaft in the inner cylindrical portion. 2. The mechanism for attaching the rotating knob to the rotating shaft according to claim 1, wherein the locking protrusion is formed in a region that corresponds to a region facing the locking recess. The elastic locking portion of the rotation knob is located only in an area closer to the top plate than a position facing the through hole in a region where the locking protrusion faces the locking recess of the rotation shaft. 3. The mechanism for attaching the rotating knob to the rotating shaft according to claim 1, wherein the mechanism is formed by: The top plate portion of the rotary knob is provided with a hole having a projected planar shape at a projected position when the locking protrusion of the elastic locking portion on the top plate portion is projected in the axial direction. A mechanism for attaching a rotating knob to a rotating shaft according to claim 1 or 2 . The rotating shaft of the rotating knob according to claim 1 or 2, wherein a corner of an opening of the rotating shaft on a side opposite to a side where the locking recess is formed is chamfered. mounting mechanism.

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