JPS5882231A - Fixing method for coil spring and shaft - Google Patents

Abstract

PURPOSE:To fix a coil spring very easily, by fitting a ring part onto the outside of the fixing end of the coil spring and crushing this ring part to fix the coil spring. CONSTITUTION:In case that a shaft 1 and a coil spring 2 are fixed in a fixing end 2c of the coil spring, a ring member 13 is fitted to the outside of the fixing end 2c after the shaft 1 is inserted to the fixing end 2c of the coil spring 2. The state after fixing is shown with the oblique view in figure, and a recessed part is formed on the ring member 13 but the cylindrical part is formed flat as the single substance of the ring member.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of fixing a coil spring and a shaft, and particularly to a method of fixing a coil spring and a shaft suitable for use in a focal plane shutter mechanism of a camera.

By fixing one end of a coil spring to a shaft or other fixed end and leaving the other end open, the energy stored in this coil spring can be used as a rotating force! There are various devices used to apply stress such as I-tension.

- As an example, a part of a seven-dimensional single-brane shutter mechanism in a camera is shown in FIG. Such a mechanism is the shutter curtain 6.
A string 5 attached to the end of this shirt curtain 6. and a drive section 7. The drive section 7 has a shaft 1 attached to the outer cylinder section 4.
is inserted, the shaft 1 is fixed, the outer cylinder part 4 is rotatable, and t
Ta. A coil spring 2 is interposed between the shaft 1 and M of the outer cylinder part 4, and one end of this coil spring 2 is fixed to the shaft 1 by a fixing part 3, and the other end of the coil spring 2 is fixed to the shaft 1 by a fixing part 3. It is fixed with a fixing part 8 provided on the inner wall. On the other hand, the tip of the string 5 is fixed to a predetermined position on the outer periphery of the outer cylindrical portion 4 and is wound around the outer periphery. 1. For example, although not shown, in conjunction with a winding lever, the shirt flap 6 is moved in the first direction of force indicated by arrow A'.
When the string 5 is moved to the position shown in the figure, the string 5 is gradually untied from the outer cylinder part 4 and the outer cylinder part 4 also follows the rotation, so that a predetermined rotational energy is stored in the fill spring 2. Thereafter, when the shutter curtain 6 is returned in the direction of the arrow by a predetermined shutter means, the desired shutter operation is performed.

By the way, as an example of the prior art method for fixing the shaft 1 and the coil spring 2 in the focal plane shutter mechanism, the means shown in FIG. 2 a or b is used. FIG. 2 shows a side sectional view of such a fixing part.

Note that parts corresponding to the same parts as in FIG. 1 are given the same numbers. First, the method shown in Fig.
This is a method in which the inner diameter of the fixed end 2 & is formed to be approximately equal to the outer diameter of the shaft 1, the shaft 1 is inserted into the coil spring 2, and then fixed to the fixed end 2a with a fixing material 9 such as adhesive or solder. . Next, FIG. 2 shows a support boss 10 having a thread groove formed on its outer periphery to be screwed into the inner diameter of the fixed end 2b of the coil spring 2, and a screw on the inner periphery to be screwed into the outer diameter of the fixed end 2'b. Tightening with the groove formed is done through a so-called helical spring end support device in which the ring 11 is screwed onto the fixed end 213 in advance, and the rear shaft 1 is inserted and fixed into the insertion hole provided in the support boss 10. This is a method of fixing it.

However, under such conventional methods.

There are the following drawbacks. That is, in the former method,
If adhesive is used, the fixing part cannot withstand the operational impact when using spring stress, and the fixing strength cannot be ensured.If adhesive is used, the fixing part cannot withstand the operational shock when using spring stress, and if the method uses soldering, the process of applying curling solder and applying 7 lacs , heat melting process, etc., and require a long process.In addition, soldering is necessary to prevent corrosion of the coil spring and shaft of the fixing part due to the 7 lux residue for activating the metal surface required for the part. It also requires steps such as neutralization cleaning, drying, and anti-corrosion treatment as post-processing, which requires many man-hours for each operation, and furthermore, it has the disadvantage that it requires equipment that is difficult to manage, which greatly worsens the production cost.

On the other hand, in the latter method, the support boss 10 and the ring 11 are used for tightening.

The assembly process increases the number of parts, requires precision machining such as forming thread grooves on the parts themselves, and is further screwed onto the coil spring in advance.

The production process for fixing this assembly to the shaft is complex and requires multiple steps, resulting in high costs and the product itself is large, making it difficult to adapt to precision small parts. There is.

In view of these drawbacks, it is an object of the present invention to provide a simple and highly reliable fixing method for fixing a coil spring and a shaft, thereby eliminating the drawbacks of the conventional methods. Still another object of the present invention is to provide a method for fixing a coil spring and a shaft, which makes it easy to mechanize and automate the assembly of such precision parts.

In order to achieve the above object, the present invention fixes a fill spring and a shaft inserted into the coil spring by fitting a ring member on the outside of the fixed end of the coil spring and crushing the ring member. It is characterized by being fixed by applying plastic deformation to the ring member. The present invention will be explained in detail below using specific examples.

FIG. 3 shows an embodiment according to the present invention, and in FIG. 0, which shows a side sectional view when a coil spring and a shaft are fixed, 1 is a shaft, and 2 is a coil spring.

2& is the fixed end of the coil spring 2 and its inner diameter is the coil spring 2.
It has a smaller diameter and is formed so that it can fit into the outer diameter of the shaft 1. Therefore, the shaft 1 and the coil spring 2 are connected to the fixed end 2 of the coil spring.
6, first insert the shaft 1 into the fill spring 2 and the fixed end 2o, and then insert the hinge member 1 according to the present invention.
3 is fitted onto the fixed end 2o.

In addition, FIG. 3 illustrates the state after identification, and the ring member 13
The ring member is formed into four parts, but before it is fixed, that is, the ring member itself is formed into a cylindrical shape with a flat cylindrical part.

Then, the ring member in the externally fitted state is crushed and fixed from the outside using, for example, a predetermined press device. FIG. 4 shows a perspective view clearly showing the crushing portion 12 of FIG. 3. In addition, although the example shows the case where the crushed portions 12 are provided intermittently, such crushed portions may be continuous.

Moreover, it is not limited by quantity, shape, etc. Although the shaft 1 can of course be implemented with a flat outer shape, holes or notches are formed on the outer periphery of the fixed portion of the shaft 1 as shown in FIG.

It is also desirable to form grooves and other recesses 1&. In this case compared to the flat case.

It is possible to significantly improve the fixing strength.

The ring member 13 is usually made of a metallic plastic material, but it can also be made of another material 1, such as a thermoplastic synthetic resin, and fixed by being plastically deformed by heating. Note that in the embodiment, the focal plane shutter mechanism of the camera was explained.

The fixing method according to the present invention can be similarly applied to other similar mechanisms. Therefore, unlike the fixing method under the conventional method, various complicated steps or devices are not required. It is extremely simple and easy to implement, resulting in a significant reduction in overall costs from parts to assembly. Moreover, since it is crushed, sufficient fixing strength is ensured and a highly reliable product can be obtained.Furthermore, since the fixing method is simple and complicated work processes are not required, it is extremely easy to mechanize and automate the process. .

Furthermore, it is possible to reduce the cost F.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram showing a part of a focal plane shutter mechanism in a camera, and FIGS. 2(a) and 2) are side sectional views of a fixing part showing a conventional method of fixing a coil spring and a shaft. FIG. 3 is a side sectional view of a fixing portion showing a method of fixing a fill spring and a shaft according to the present invention, and FIG. 4 is a perspective view of FIG. 3. 1&...Concave portion 20...Fixed end of coil spring 12...Crushed portion 13...Ring member Fig. 1 2nd factor (0)

Claims (4)

[Claims] (1) When fixing a coil spring and a shaft inserted into the coil spring, a ring member is fitted outside the fixed end of the coil spring. Method 0 for fixing a fill spring and a shaft, characterized by fixing the ring member by crushing it (2) A method for fixing a coil spring and a shaft according to claim 1, wherein the fixing portion of the shaft is formed with a hole, a notch, or a recessed portion such as a window. (3) A method for fixing a coil spring and a shaft according to claim 1, wherein the ring member is formed of a plastic material◇ (4) A method for fixing a coil spring and a shaft according to claim 1, wherein the ring member is made of synthetic resin or other thermoplastic material and is fixed by heating means. . .