JPH05240972A - Attaching structure for operation knob - Google Patents

Abstract

PURPOSE:To prevent the slip-out of a knob while facilitating the removal of the knob. CONSTITUTION:In the attachment structure of the knob 31 operating an encoder 1, a pawl-shape projection 33 is provided to the outer periphery of the fitting part 32 of the knob 31 with the operation shaft 2 of the encoder 1. The projection 33 comes into contact with the through-hole in which the fitting part 32 is inserted of the panel 25 to which the encoder 1 is fixed by a screw 30 in the vicinity of the peripheral edge of said hole to prevent the detachment of the knob 31 from the encoder 1. The hinge part 28 integrated with the panel 25 and the groove part 29 continuing to the through-hole are provided in the vicinity of the peripheral edge of the through-hole of the panel 25. The hinge part 28 is provided at the position coinciding with the position of the projection 33 when the operation shaft 2 returns to a central position in such a state that the knob 31 is attached to the encoder 1. The groove part 29 is provided at the position coinciding with the position of the projection 33 when the operation shaft 2 of the encoder 1 is fully revolved in a counterclockwise direction to stop.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a knob mounting structure for operating an automatic reset type variable resistor. Here, the automatic reset type variable resistor is a variable resistor in which a rotating operation shaft is always biased by a spring so as to return to a central position, and is used as an encoder in a VTR or a tape deck, for example. It has been done. Incidentally, the encoder used for the VTR has two rotary operation shafts arranged coaxially, and the outer operation shaft returns to the central position. When the operation shaft is rotated rightward or leftward from this central position, the fast-forwarding or rewinding speed of the video tape is changed according to the angle of this rotation. The inner operation shaft is for adjusting the frame feed speed.

[0002]

2. Description of the Related Art Conventionally, as a mounting structure of a knob for operating an encoder used in a VTR, one shown in FIG. 3 is known. FIG. 3 shows a state in which the knob for operating the encoder is removed. In FIG. 3, reference numeral 1 denotes an encoder, which has two rotary operation shafts arranged coaxially. Reference numeral 2 is an outer operation shaft, and 3 is an inner operation shaft. Reference numeral 4 denotes an outer knob, which has a tubular fitting portion 5 that fits into the outer operation shaft 2. Reference numeral 6 denotes an inner knob, which has a tubular fitting portion 7 that is fitted to the inner operation shaft 3. Reference numerals 8 and 9 are protrusions provided on the fitting portions 5 and 7, respectively, and are fitted into the grooves (not shown) of the operation shafts 2 and 3, so that the knob 4, the operation shaft 2, and the knobs are provided. It is intended to prevent the sliding of the operation shaft 6 and the operation shaft 3 in the rotating direction. Reference numeral 10 denotes a recess provided on the front surface of the knob 6 for inserting a finger and rotating the knob.

In the above mounting structure, the operating shaft 3 and the fitting portion 7
And the inner diameters d and c of the fitting portions 5 and 7 with respect to the outer diameters e and f of the operating shafts 2 and 3 so that the fitting of the operating shaft 2 and the fitting portion 5 becomes tight. It is determined that the tight fitting of these prevents the knobs 4 and 6 from coming off.

However, in the embodiment described with reference to FIG. 3, the operating shafts 2, 3 in a high temperature environment or a low temperature environment are used.
Due to the difference in expansion amount or contraction amount between the fitting portions 5 and 7, the above-mentioned fitted state is loosened, and the knobs 4 and 6 are easily removed. In order to prevent this disengagement, it is necessary to fit more tightly at normal operating temperatures. If the fitting is sufficiently tight as described above, the workability of mounting the knobs 4 and 6 is deteriorated, and the encoder 1 is not tightened due to excessive tightening of the operation shafts 2 and 3.
Adversely affect the inside of the. Further, if the knobs 4 and 6 are tightly fitted together as described above, a considerable pulling force is required when the knobs 4 and 6 are replaced for service. At the time of this replacement, depending on the case, the cover of the VTR is opened and the encoder 1 is detached, so that the encoder 1 is easier to pull than the knobs 4 and 6.
The knobs 4 and 6 may be removed from the encoder by pulling. For this reason, work efficiency becomes poor.

As described above, the knob 4, depending on the temperature change,
As shown in FIG.
The operation knob mounting structure shown in is also known. In FIG. 4, 1 is an encoder, 4 is an outer knob, and 6 is an inner knob, which are the same as those denoted by the same reference numerals in FIG. FIG. 4 shows a state in which the knobs 4 and 6 are removed from the encoder 1. Reference numeral 11 is a metallic ring fitted to the outer periphery of the fitting portion 7. Reference numeral 12 is a metallic hook, which is fitted around the fitting portion 5. 1
3 is a split groove provided in the fitting portion 7, and 14 is a split groove provided in the fitting portion 5. Reference numeral 15 is a stopper of the snap ring 12 formed of a protrusion provided on the outer peripheral surface of the fitting portion 5. Reference numeral 16 denotes a groove provided on the operation shaft 2, which is fitted to a protrusion provided on the inner peripheral surface of the fitting portion 5 (not shown) to allow the operation shaft 2 and the knob 4 to slide in the rotating direction. Is to prevent.

In the operation knob mounting structure described with reference to FIG. 4, since the ring 11 and the ring 12 are metallic, the expansion amount or the contraction amount with respect to the temperature change is larger than that of the fitting portions 5 and 7 formed of synthetic resin. It is possible to prevent the knobs 4 and 6 from easily coming off due to a temperature change. However, the number of parts and the work process increase, which causes a cost increase. Further, the problem that it is difficult to remove the knobs 4 and 6 has not been solved.

As a means for preventing the knobs from coming off easily, the one shown in FIG. 5 is also known (actual opening 03-
57696). In FIG. 5, reference numeral 17 denotes an operation panel, and a rotary volume control 18 is fixed to the panel 17. Reference numeral 19 denotes an operation knob, which has a fitting portion 21 that fits with the rotary shaft 20 of the volume 18, and a protrusion 23 having a claw-shaped engaging portion 22 formed at its tip. 24 is an arc hole provided in the panel 17,
The engaging portion 22 of the protrusion 23 is inserted. In such an operating knob mounting structure, the engaging portion 22 is caught on the inner surface of the panel 17, and the knob 19 is prevented from coming off. However, the problem that it is difficult to remove the knob 19 has not been solved yet.

[0008]

As described above, the conventional operation knob mounting structure has a drawback that it is difficult to remove the knob. The present invention eliminates the above-mentioned drawbacks, and an object of the present invention is to provide an operating knob mounting structure that prevents the knob from coming off and facilitates removal of the knob.

[0009]

SUMMARY OF THE INVENTION To achieve the above object, the present invention provides a knob mounting structure for operating an automatic reset type variable resistor, wherein the automatic reset type variable resistor in the knob is connected to the automatic reset type variable resistor. By providing a protrusion on the outer periphery of the fitting portion and bringing the protrusion into contact with the vicinity of the peripheral edge of the through hole into which the fitting portion is inserted in the panel having a fixed relationship with the automatic reset type variable resistor, the knob is provided. So as not to come off from the automatic reset type variable resistor, and in the vicinity of the peripheral edge of the through hole of the panel, a hinge portion and a groove portion which are integral with the panel and which are capable of passing the protrusion are partially different from each other. The operating knob mounting structure is characterized in that it is provided at a position.

[0010]

In the operation knob mounting structure configured as described above, when the knob is mounted, the knob is adjusted so that the protrusion is aligned with the position of the hinge portion and the fitting portion is fitted to the automatic reset type variable resistor. Push in. As a result, the hinge portion is pushed and bent by the protrusion, and the protrusion gets over the hinge portion and fits inside the panel. Therefore, the knob is less likely to come off the automatic reset type variable resistor. Further, when removing the knob, the protrusion is aligned with the position of the groove and the knob is pulled out. In this case, since the protrusion does not come into contact with the panel, the knob can be easily removed.

[0011]

Embodiments of the present invention will be described below with reference to FIGS. 1A shows a state where the knob is attached to the encoder, and FIG. 1B shows a state where the knob is being attached to the encoder. 2 (a) is a front view of the panel when the encoder is attached, and FIG.
2B shows the front surface of the panel when the encoder is not attached, and FIG. 2C shows the front surface of the outer knob. In FIGS. 1 and 2, the same members are designated by the same reference numerals, and the same members as those shown in FIGS. 3 and 4 are designated by the same reference numerals.

In FIG. 1, reference numeral 25 denotes a panel made of synthetic resin, in which a boss 26 and a hinge portion 28 are integrally formed, a through hole 27 (shown in FIG. 2B), and a through hole. A continuous groove portion 29 (shown in FIGS. 2A and 2B) is bored. The encoder 1 is attached to the boss 26 with a screw 30, and the operation shaft 2 outside the encoder is loosely fitted in the through hole 27. Reference numeral 31 denotes an outer knob, which is integrally formed with a cylindrical fitting portion 32 that fits with the operation shaft 2 of the encoder 1, and has a claw-shaped projection 33 integrally formed on the outer periphery of the fitting portion 32. It is projected. 34
Is a ridge protruding from the inner peripheral surface of the fitting portion 32, and is fitted into a groove (not shown) provided on the outer peripheral surface of the operating shaft 2 so that the operating shaft 2 and the knob 31 It is intended to prevent slipping in the direction of rotation with.

The hinge portion 28 has a position of the protrusion 33 when the knob 31 is attached to the encoder 1 as described later and the encoder is not operated (the operation shaft 2 is returned to the central position). It is provided at a position corresponding to. Further, the groove portion 29 is provided at a position corresponding to the position of the protrusion 33 when the operation shaft 2 of the encoder 1 is fully rotated counterclockwise with the knob 31 attached to the encoder 1 and is stationary. Has been.

In the operation knob mounting structure constructed as described above, when the protrusion 33 is aligned with the position of the hinge portion 28 and the knob 31 is pushed in the direction of the arrow in FIG.
The hinge portion 28 pushed by 3 bends, the projection 33 passes through the hinge portion 28, and the fitting portion 32 is fitted to the operation shaft 2. In this state, the hinge portion 28 returns to the original state as shown in FIG. 1A, and the knob 31 becomes difficult to come off from the encoder 1. Thereafter, the fitting portion 7 of the knob 6 is inserted into the central hole of the knob 31 and fitted to the operation shaft 3, whereby the knobs 6 and 31 are attached to the encoder 1 as shown in FIG. It becomes a state.

To remove the knobs 6 and 31 from the state where the knobs 6 and 31 are attached to the encoder 1 as shown in FIG. 1 (a), the knob 31 is first moved to the positions shown in FIGS. As indicated by α, the rotating operation is performed to the stationary position in the counterclockwise direction. In this state, the position of the protrusion 33 coincides with the position of the groove 29, and therefore the protrusion 31 is pulled by pulling the knob 31.
After passing through the groove 29, the knob 31 is removed. At the same time, the knob 6 is also pushed by the knob 31 and removed.

In the operation knob mounting structure described above, FIG.
Even when the knobs 6 and 31 are attached as shown in (a) and the knob 31 is pulled when the operation shaft 2 and the fitting portion 32 are loosened due to a large temperature change, the protrusions 33
Is caught on the hinge portion 28, so the knob 31 cannot be removed. If the dimension a shown in FIG. 1A is smaller than the dimension b, the knob 6 can be pulled even when the knob 31 is pulled.
Since the knob 6 is not pushed up by the knob 31 and the knob 6 itself is not touched, the knob 6 cannot be easily pulled out. Therefore, there is no excessive tightening on the encoder 1 under normal operating temperature, and there is no need for a separate component such as a ring or a ring.

When the knobs 6 and 31 are removed, the projection 3
3 so that 3 fits into the position of groove 29 of panel 25
By rotating 1 and pulling it, the knobs 6 and 31 can be removed with a small force, which does not require a cost and has good workability. In the above-described embodiment, the projection 33 has a claw shape, but the projection 33 can be implemented without providing a slope forming the claw shape. The groove 29 is provided at a position corresponding to the position of the projection 33 when the operation shaft 2 of the encoder 1 is fully rotated clockwise in a state where the knob 31 is attached to the encoder 1 and is stationary. Can also be implemented.

Incidentally, the main part of the configuration of the above embodiment is as follows. A mounting structure of a knob 31 for operating the encoder 1, wherein a claw-shaped projection 33 is provided on an outer periphery of a fitting portion 32 of the knob 31 with the operation shaft 2 of the encoder 1.
And the protrusion 33 is brought into contact with the vicinity of the peripheral edge of the through hole 27 into which the fitting portion 32 is inserted in the panel 25 to which the encoder 1 is fixed by the screw 30. So that it doesn't come off. In the vicinity of the peripheral edge of the through hole 27 of the panel 25, the hinge portion 28 integral with the panel 25 and the groove portion 2 following the through hole 27, through which the protrusion 33 can pass.
9 is provided. The hinge portion 28 is provided at a position corresponding to the position of the protrusion 33 when the operation shaft 2 is returned to the central position with the knob 31 attached to the encoder 1. Further, the groove portion 29 is provided at a position corresponding to the position of the protrusion 33 when the operation shaft 2 of the encoder 1 is fully rotated counterclockwise with the knob 31 attached to the encoder 1 and is stationary. Has been.

[0019]

Since the present invention is constructed as described above, it is possible to prevent the knob from coming off and to easily remove the knob.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view showing an embodiment of the present invention,
(A) shows a state where the knob is attached, and (b) shows a state where the knob is being attached.

FIG. 2 is a partial front view of the embodiment of the present invention,
(A) shows a panel with an encoder attached, (b) shows a panel with the encoder removed, and (c) shows an outer knob.

FIG. 3 is a vertical cross-sectional side view showing a first conventional example, showing a state in which a knob is removed.

FIG. 4 is a side view showing a second conventional example, showing a state in which a knob is removed.

FIG. 5 is a vertical cross-sectional side view showing a third conventional example, showing a state in which a knob is attached.

[Explanation of symbols]

 1 Encoder 2 Operation Axis 3 Operation Axis 25 Panel 27 Through Hole 28 Hinge Part 29 Groove Part 31 Knob 32 Fitting Part 33 Protrusion

Claims (1)

[Claims] 1. A structure for mounting a knob for operating an automatic reset variable resistor, wherein a protrusion is provided on an outer periphery of a fitting portion of the knob with the automatic reset variable resistor, and the automatic reset variable resistor is provided. In the panel in a fixed relationship with the container, by the protrusion abutting near the periphery of the through hole into which the fitting portion is inserted,
The knob is arranged so as not to come off from the automatic reset type variable resistor, and a hinge part and a groove part which are integral with the panel and which allow the protrusion to pass through are provided in the vicinity of the peripheral edge of the through hole of the panel. Operation knob mounting structure characterized by being provided at different positions.