JPS6243512B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a non-circular case back for a non-circular timepiece and a method for manufacturing the same.

The purpose of the present invention is to improve workability, reproducibility, and reliability by simplifying the structure of a non-circular case back.Other purposes are to improve workability, reproducibility, and reliability of the case back with a non-circular shape. The goal is to improve degradability. Another objective is to make the entire non-circular timepiece thinner and smaller by making the non-circular case back thinner. Another object of the present invention is to provide a method for manufacturing a back cover having a non-circular shape having the above-mentioned object at low cost, easily, and as an integral unit.

Conventionally, non-circular case backs used for this kind of non-circular watches, such as circular case backs, can be easily cut using a suitable tool such as a cutting tool in addition to a cutting machine such as a lathe. Therefore, various structures have been devised so far. For example, in order to attach a pin to a groove provided in a non-circular body, a leaf spring is fixed directly to the back cover, and a pin is further fixed to this leaf spring, or a so-called dowel is attached. For this reason, one example is one in which a core with a dowel with a dowel is integrally fixed to a non-circular case back.

As an example, a non-circular back cover with pin holes will be explained with reference to FIG.

In FIG. 1, 1 is a stepped glass, 2 is a non-circular back cover, and 3 is a glass gasket, which is compressed and held between the lower surface of the stepped glass 1 and the upper surface of the back cover 2. 4 is a non-circular body provided with a groove 4a. 5 is a leaf spring fixed to the back cover 2, and a pin 6 is fixed to the leaf spring 5. This leaf spring 5
The gasket 3 is pressed by fitting and engaging a pin 6 fixed to the groove 4a of the body 4. In this way, with the pin-biting structure shown in FIG. 1, since the leaf spring 5 and pin 6 are directly fixed to the back cover, a storage space 2a for storing the pin 6 is inevitably required. The dimensions and shape of the case back become larger, and the thickness in particular becomes larger, resulting in the overall thickness of the watch. Furthermore, it was necessary to add parts such as leaf springs and pins to the back cover that were separate from the back cover, which was very inconvenient in terms of workability and cost. Furthermore, in order to increase the bonding strength between the case back and the case, the engagement between the pin and the case may be provided at two or more places instead of just one, and these multiple engagements must be released each time the mechanical body is repaired or the battery is replaced. It was very troublesome. Also, because the gap between the camera back and the body is large, moisture such as sweat gets into this gap and stays there all the time, which not only poses problems in terms of functionality such as waterproofness and corrosion resistance. This gap was noticeable in terms of appearance and lacked a sense of beauty.

The present invention has been made in view of the above-mentioned drawbacks, and has a simple structure, improved workability, reproducibility and reliability, easy assembly and disassembly with the body, and a non-circular shape. The purpose of this invention is to provide an inexpensive non-circular back cover and a method for manufacturing the same, with the aim of making the entire watch thinner and smaller.

The gist of the present invention to achieve the above object is as described in the claims above.

Next, a preferred embodiment of the present invention will be described in detail with reference to the drawings from FIG. 2 onwards.

In FIG. 2, reference numeral 10 denotes a non-circular body, and a non-circular flat glass 12 is fixed to the upper part of the body through a glass gasket 11 by known means such as press-fitting or bonding. Reference numeral 13 denotes a non-circular back cover according to the present invention, which has a rectangular shape shown in FIG. 5 as an example of a non-circular shape. It consists of a rising part 15 which is integrally formed by pressing etc. on the entire outer edge vertically, except for the corner parts 15a of the rising part 15 (4 places in the case of a rectangular shape as shown in Fig. 5). The part is almost 3
There are provided biting portions 15b (in the case of FIG. 5, there are four substantially straight rising portions) that are inclined inward at an inclination angle α of about 7 degrees. If this biting part 15b is fitted into the engagement groove part 16 provided at the lower part of the body 10 in a snap fit manner,
The non-circular body and back cover can be joined together very easily. Reference numeral 17 denotes a back cover gasket, which is provided between the case 10 and the case back 13, and is pressed in the vertical direction by fitting the bite part 15b of the case back into the engagement groove 16 of the case, thereby achieving a waterproof function. It is. Reference numeral 18 denotes a slot for opening the case, which is provided in the case 10 and is used when separating the back cover from the case.

In this way, with the non-circular shaped back cover of the present invention, a snap structure similar to that of a circular back cover can be obtained, and it is an integral structure that does not require additional parts such as leaf springs and pins as in the conventional case. Furthermore, since no storage space is required for leaf springs, pins, etc., the back cover itself can be easily made thinner and smaller, and as a result, the entire watch can be made thinner and smaller. In addition, it can be easily disassembled from the case by using the pry-opening groove provided on the case to pry open one place, and even when reassembling, the case back can be attached to its base in the same way as the circular case back snap. All you have to do is press the surface part, and it is much easier to assemble and disassemble than conventional structures such as those with pin bites. Further, with the back cover structure according to the present invention, it is possible to use a plate material with a thickness of about 0.3 mm, making it possible to make the camera thinner and more compact, and further improve the stickability.

In addition, in this embodiment, the rising portion 1 in the cross section
Although the bite portion 15b in No. 5 is shown as being inclined as a whole, it is of course possible to form the bite portion by making only the upper end portion of the rising portion 15 be inclined.

Next, a method for manufacturing a non-circular back cover according to the present invention will be explained with reference to FIG. 3 and subsequent figures.

Although the present embodiment shows a non-circular back cover having a rectangular shape, the present invention is not limited to this, and it goes without saying that the back cover may have a non-circular shape such as a square, a pentagon, or a rhombus.

First, a large number of stainless steel plates or combs with a thickness of about 0.3 mm to 0.7 mm are continuously pressed at high speed into blanks 19 for non-circular case backs as shown in Fig. 3 from a strip material. Leave the material blank.

Next, the press-cut blanks 19 are automatically or manually fed one by one into a very general drawing die consisting of an upper die and a lower die, and the blanks 19 are fed one by one into an extremely common drawing die consisting of an upper die and a lower die, so that the blanks 19 are shaped like an alpha-abbet "U" in cross section as shown in Fig. 4. Draw it into a letter shape. By this drawing forming, a continuous rising portion 15 is formed on the entire outer edge. In this drawn state, the base surface 1 of the rising portion 15
4. Variation in height, especially corner part 15a
The height of the rising portion 15 is increased, so in order to keep this height constant from the base surface, the end surface 15 of the rising portion 15 is
The length of the end face of a is adjusted using a cutting tool or a rotating grindstone to the point shown by the dashed line in FIG. 4, and a process is performed to make the end face uniform so that the height from the base surface is constant. (In Fig. 4, the height up to the dashed line indicating the length is exaggerated.) Next, in order to remove chips etc. generated by the above flattening process, a cleaning solution such as bright oil or triclean is applied. After some post-processing, the part of the rising part 15 excluding the corner part 15a is formed into a part 1 which is inclined inward at an inclination angle α of approximately 3 degrees to 7 degrees.
5b is performed to obtain a non-circular (rectangular) back cover of the present invention as shown in FIG. The product obtained in this way is further subjected to some post-processing, such as degreasing and drying treatment,
The entire process of the invention can be completed.

Preferably, after the press-forming of the biting portion 15b, water is poured into the barrel in order to remove burrs from the end surface 15c of the rising portion 15 caused by the press-forming or the flattening treatment due to the length of the rising portion. Then, hundreds or thousands of case backs are inserted, and if necessary, pebbles or sand are added, and the barrel is rotated at a low speed of several tens of revolutions per minute to remove burrs. After this, I remove the camera back from the barrel and dry it with hot air. By performing such deburring, the engagement groove 1 of the shell 10 shown in FIG.
6 and the biting part 15b of the rising part 15 of this back cover 13
When snap-fitting, the end of the biting part 15b has no burrs, so it can be fitted smoothly.

As described above, according to the method of the present invention, a non-circular camera back can be manufactured extremely easily using only press molding, and there is no need for plate springs, pins, etc., which are separate components from the conventional camera back components. This makes the structure simple and inexpensive, and by flattening and deburring the end face of the rising portion, it is possible to obtain a non-circular back cover with further improved reproducibility and reliability.

In addition, although the base surface of the back cover is shown as flat in this example, by using a thin plate material and making the rising part a gentle curved surface at the same time, a non-circular shaped back surface with better biteability can be created. You could also easily get the lid.

As explained in detail above, according to the present invention, when the watch body has a non-circular shape, it is possible to easily process and manufacture a back cover with a non-circular shape corresponding to the watch body, which is inexpensive, and has a mechanical structure. Because it is easy to separate and attach the case and back cover during repairs or battery replacement, it is possible to improve after-sales service, and since it is made of one piece, reliability and reproducibility are improved. Can be done. Furthermore, compared to conventional watches, the entire watch can be made extremely thin and compact, and the external design and functionality of a non-circular watch can be comprehensively improved. It is extremely effective and versatile.

[Brief explanation of the drawing]

Fig. 1 is a partial vertical cross-sectional view of a conventional non-circular case back with a pin bit installed in a watch;
FIG. 2 is a partial vertical cross-sectional view of the non-circular back cover of the present invention using the snap-fit method, and FIGS. 3, 4, and 5 show the non-circular shape of the present invention shown in FIG. FIG. 3 is a plan view of the blank, and FIG. 4 is a state in which the blank shown in FIG. 3 is drawn with a press to form a rising part. Longitudinal cross-sectional view of
FIG. 5 is a perspective view of the rising portion further press-molded to provide a bite portion. FIG. 6 is a sectional view taken along the line -- in FIG. 13... Back cover, 14... Base, 15... Rising part, 15a... Corner part, 15b... Biting part,
15c... end face, 19... blank.

Claims (1)

[Scope of Claims] 1. An external press punching step for obtaining a blank for the back cover from a metal plate material, a drawing step for forming a rising portion on the entire outer edge of the blank, and a drawing step for forming a rising portion on the entire outer edge of the blank, the rising portion of the step being inclined inward except for corner portions. A method for manufacturing a non-circular watch back cover, which includes a press molding process to form a biting part. 2. An external press punching process for obtaining a back cover blank from a metal plate material, a drawing process for forming a rising part on the entire outer edge of the blank, a flattening process for the end face of the rising part, and a process for flattening the rising part of the above process except for corner parts. A method for manufacturing a non-circular watch back cover, which includes a press molding process that forms an inwardly inclined part. 3. An external press punching process to obtain a back cover blank from a metal plate material, a drawing process to form a rising part on the entire outer edge of the blank, a flattening process for the end face of the rising part, and a process of flattening the rising part to the inside except for corner parts. a press molding process of forming an inclined biting part;
A method for manufacturing a non-circular watch back cover, comprising the step of deburring the end face of the rising portion in the above step.