JPH0139932Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a bearing structure that applies a braking load to a rotating shaft, and is used in the field of air conditioning equipment such as automobile registers.

[Conventional technology]

Conventional braking means for the rotation shaft of the register include, for example, the rotation control of the barrel as shown in FIGS. 5a to 5e.
When fitting and supporting the shaft in the bearing hole of a bezel made of plastic such as ABS, a step 21' with a thickness d ₁ is formed at the base of the barrel shaft, and the step allows the opposing barrel outer wall surface and barrel inner wall surface to be connected to each other. _A gap 〓d ₁ is maintained in between, _and a shim (thickness adjustment The rotation of the barrel 2 with respect to the bezel 1 is braked by the frictional force generated by the pressing force of the inner wall surface of the bezel and the outer wall surface of the barrel against the shim.

[Problem that the invention attempts to solve]

The braking force generation effect by the shim 3 is used because it attempts to deform the side wall of the barrel 2 and the side wall of the bezel ₁ in the directions of arrows F1 and _F2 , as shown in Figure 5e. In the meantime, the initial setting load decreases. When a felt plate as shown in Figure b is used as a shim, the felt itself is compressively deformed and its initial plate thickness decreases, and as the thickness decreases with each operation, the braking load decreases.

Also, if the bezel or barrel is made of plastic, it will deform due to the effects of heat and time. For example, according to a practical heat resistance test assuming heating and parking under the scorching sun in midsummer, if both the bezel and barrel are made of ABS resin, the load after the heat resistance test is less than 25% of the initial load. It declined to .

In the end, with these conventional shaft brakes, if the shim is made of felt, the shim becomes thinner, and if the shim does not deform and become thinner, as shown in Figure e, the space between the bezel side wall and the barrel side wall will expand and deform. , it is unavoidable that the default load will deteriorate over time with use, and it is also difficult to improve the accuracy of load management because the factors in the set load are the width of the bezel, the width of the barrel, and the thickness of the shim. Ta.

[Means and actions for solving problems]

The present invention eliminates or improves the above-mentioned defect of the initial load (set load) that deteriorates over time due to the use of the initial load (set load), which could not be avoided due to the structure of the conventional device. 4 A plurality of large diameter portions 41 and an inwardly curved portion 4 between the large diameter portions as shown in 4 in FIG.
2, a slit S for expansion deformation is cut in one of the large diameter parts of the tubular spring 4, and a rotation prevention piece is placed on the spring 4, and the large diameter part is fitted into the inner periphery of the bearing hole 11. At the same time, by preventing the spring 4 from rotating relative to the bearing hole 11 with the rotation prevention piece and pressing the barrel shaft 21 at the small diameter contact point P, the rotation of the barrel shaft 21 is prevented only by the elastic properties of the spring 4. The deficiencies of conventional devices have been eliminated or improved by providing a structure that controls friction.

In other words, in the configuration of the present invention, no matter what kind of stress is generated by the spring, neither expansion deformation of the bearing hole 11 of the bezel nor compressive deformation of the diameter of the barrel shaft 21 occurs, so that the load (stress) acting surface as in the conventional device is not affected. There is no reduction in braking force due to load deformation of the bezel side wall and barrel side wall, and since the only load factor is the spring, load management becomes accurate and easy.

In addition, since the spring has a rotation prevention piece, when fitting the spring into the bearing part, the rotation prevention piece is locked to the bearing hole side to prevent the spring from rotating or coming out. By holding it temporarily, it was easy to insert and fit the barrel shaft. Furthermore, due to the presence of the slits S, the spring has an elastic action as a whole added to the elastic action of each curved portion 42, so that a synergistic braking force can be suitably applied, and dimensional errors in the tubular diameter of the spring can be suitably absorbed. Ta.

〔Example〕

(Example 1) As shown in Figures 2 and 3, width 3 mm thickness 0.3
mm spring steel plate with a radius of curvature of the curved part 42 of 2.8 mm,
The diameter of the virtual circle formed by the three small diameter contact points P having an angular interval of 120° is 4.5 mm, the diameter of the virtual circle formed by the outer periphery of each large diameter portion 41 is 7.5 mm, and 1 of the large diameter portion A slit S for expansion and deformation with a width of 2 mm is formed in each piece,
An arm 43 with a thickness of 0.1 mm and a width of 2 mm is provided which protrudes outward at a right angle from the other large diameter part side end, and a locking piece 4 parallel to the spring large diameter part is provided at the tip of the arm.
3' was formed to constitute the spring 4.

The spring 4 is attached to the bezel 1 as shown in FIG.
The locking piece 4 of the arm loosely fits into the bearing hole 11 of the arm.
3' was inserted into the locking hole 11' drilled from the inner wall of the bezel. Next, the shaft is bent inward by the notch around the shaft, and then the shaft 21 of the barrel is inserted into the spring 4, and the diameter α of the virtual inscribed circle of the spring 4 is expanded and deformed to β. The shaft support structure is in the same state.

When the barrel is fitted to the bezel, as shown in FIG. 3, the diameter α of the virtual inscribed circle of the sprig 4 is expanded to the diameter β by the insertion of the barrel shaft 21, and the sprig 4 assumes the state shown in the virtual diagram. Ta. The spring 4 undergoes elastic deformation between the inner peripheral surface of the bezel bearing hole 11 and the outer peripheral surface of the barrel shaft 21, and the elastic stress that attempts to recover the deformation of the spring generates friction pressure that brakes the rotation of the barrel shaft 21. . When the barrel 2 is adjusted and rotated in the state shown in FIG. 1, the spring 4 presses and brakes the surface of the barrel shaft 21 at each contact point P while being prevented from rotating by the action of the locking piece 43' at the tip of the arm 43.

Because the rotation of the spring 4 is suppressed, the deformation of the barrel shaft is not at a fixed position, but the entire outer circumference receives smooth frictional force due to the line contact formed at point P, and the shim of the conventional device is not affected by the feeling of rubbing due to surface friction. In addition, felt shims have a slipping feeling and there is no moderation to determine the exact position, and wave washers have a feeling that scrapes the resin surface with metal, but in this example product, the wire was always tightened by a spring to tighten the line contact. I got the feeling.

Even in the same heat resistance test as before, bezel bearing hole 1
1. There is no deformation of the inner peripheral surface and the outer peripheral surface of the bezel shaft 21,
In addition, the physical properties of the spring 4 are not affected in any way, and the operating load drop of this example product is improved to less than a fraction of that of the conventional product, and extremely high load stability is achieved due to the spring characteristics. Ta.

(Example 2) In the embodiment shown in FIG. 4, instead of the arm 43 of the embodiment of Example 1, a protruding piece-shaped rotary member is used, which extends in the radial direction by half the width of one large-diameter piece of the expansion slit S. The same procedure as Example 1 was carried out except that the movement prevention piece 44 was used.

As shown in the figure, the rotation prevention piece can be easily formed by making a circumferential cut in the center of the width of one of the large-diameter pieces divided by the slit S and making only half the width stand up in the radial direction. Yes, if the spring 4 is fitted into the bearing hole 11 with the anti-rotation piece fitted into the groove (not shown) cut in the circumferential direction from the inner periphery of the bearing hole 11, the spring 4 will be removed as in Example 1. 4 can prevent rotation and can be temporarily held in the bearing hole.
The same effect as in Example 1 was achieved.

Above, both Examples 1 and 2 have been described in which the present invention is applied to a barrel shaft, but it is obvious to those skilled in the art that the present invention can also be applied to, for example, the blade part of a resistor and achieve the same effect. Will.

[Effect of idea]

Since the only load factors that brake the rotating shaft are the shaft diameter and spring, load management is much easier compared to the conventional management of bezel width, barrel width, and shim thickness (diameter control is easier than controlling width). (easier to manage).

Since neither the inner circumferential surface of the bezel bearing hole nor the outer circumferential surface of the barrel shaft is subjected to load deformation, the change in operating load over time can be significantly improved by selecting only the spring.

Since braking is performed only by the elastic deformation of the spring, the error range with respect to ideal dimensions is larger than in the conventional device, which uses elastic deformation braking using three members: the bezel side wall, the barrel side wall, and the shim, making manufacturing and management easier.

Since the spring is equipped with a rotation prevention piece, when installing the spring, the spring can be temporarily held in the bearing hole by locking the rotation prevention piece to the bearing hole side, so the braking device Assembling has become easier. Further, since the spring is fixed to the bearing hole side even when the braking device is in operation, the braking force is applied by the sliding friction force only at the small diameter contact point P of the spring, and a smooth and stable braking force can be applied.

In addition, because the spring has a slit for expansion deformation, it is easy to install, and a synergistic effect is obtained between the elasticity of each curved part and the elasticity derived from the overall shape, and the spring manufacturing process The elastic braking force was able to be exerted to absorb the dimensional error.

[Brief explanation of drawings]

FIG. 1 is a schematic sectional view of the present invention, FIG. 2 is a perspective view of a spring used in the present invention, FIG. 3 is an explanatory diagram of the action of the spring, and FIG. 4 is an explanatory diagram of the action of the deformable spring. The figures in FIG. 5 relate to a conventional example, where a shows a schematic cross-section, b shows a shim made of felt, c shows a shim made of a wave spring, and d shows the state in which the shim is attached to the barrel shaft. ,
e indicates the action of the shaft portion. 1...bezel, 11...bearing hole, 2...barrel, 21...barrel shaft, 3...shim, 4...spring, 43...spring arm.

Claims (1)

[Scope of utility model registration request] A plurality of large diameter portions 41 and an inwardly curved portion 42 between the large diameter portions
An expansion deformation slit S is cut in one of the large diameter parts 41 of the spring 4 having
1 is fitted into the inner periphery of the bearing hole 11 and the rotation prevention pieces 43 and 44 prevent the spring 4 from rotating relative to the bearing hole 11. The shaft 21 having a slightly larger diameter β than the tangent circle α is inserted into the spring 4, and the spring 4
A rotary shaft braking device that derives elastic deformation.