WO2019033795A1

WO2019033795A1 - Method for reducing inside-housing length tolerance of back housing of wristband

Info

Publication number: WO2019033795A1
Application number: PCT/CN2018/085274
Authority: WO
Inventors: 翁速峰
Original assignee: 广东乐源数字技术有限公司
Priority date: 2017-08-17
Filing date: 2018-05-02
Publication date: 2019-02-21
Also published as: CN107379569A

Abstract

A method for reducing inside-housing length tolerance of a back housing of a wristband. The wristband comprises a plastic back housing and a decorative edge component (1) for mounting a watch band. The method comprises: SS1, forming a plastic back housing by injection molding, wherein a left end portion and a right end portion of an upper side surface and a lower side surface of the plastic back housing are each provided with a vertical insertion hole (3), and the depth of the vertical insertion hole (3) is 2-4 mm; SS2, using an aluminum alloy decorative edge component (1) as the decorative edge component (1), providing two fitting columns (4) on the aluminum alloy decorative edge component (1) by means of CNC programming, wherein the two fitting columns (4) are located on the same side of the aluminum alloy decorative edge component (1), the two fitting columns (4) are formed in a one-pass process by means of CNC programming, eliminating the need to change a fixture, and the relative positional dimensional tolerance between the two fitting columns (4) is ±0.02 mm; and SS3, fitting the fitting columns (4) of the aluminum alloy decorative edge component (1) into the vertical insertion holes (3) of the plastic back housing, wherein the fitting column (4) and the vertical insertion hole (3) form an interference fit.

Description

Method for reducing length tolerance in rear shell of hand ring

Technical field

The invention relates to a method for processing a back shell of a wristband, in particular to a method for reducing the tolerance of the length of the shell of the bracelet.

Background technique

The smart sports bracelet is now more and more trusted by users, and has even become a must-have for everyday life. In order to increase the body feeling worn by the user, the plastic bracelet is the material of most bracelets in the market. The back shell of the bracelet is typically manufactured using an injection molding process.

The size of the bracelet is very small, and the battery, motherboard, screen and various sensors need to be set inside, so it is necessary to arrange and cooperate with each component to increase the stability of the bracelet. However, since the plastic back shell is limited by the injection molding process during injection molding, there is a large tolerance in the hollow shell for placing various types of parts in the back shell, and the tolerance range is generally ±0.04 mm (as shown in the drawing) 1)), in this way, when installing various types of parts, there are some too tight, and some are too loose, which may cause the subsequent bracelet to loose or crack when used.

In order to enable the detachable assembly of the bracelet with the strap, a decorative edge 1 is respectively arranged on the side of the rear shell of the bracelet, and perforations for mounting the strap are respectively arranged at the two ends of the decorative edge. (As shown in Figure 2), the groove is milled in the middle of the decorative edge and glued in the groove. Bone position 2 (shown in FIG. 3) is disposed on both sides of the back shell of the bracelet, and the bone position 2 is fitted with the groove on the decorative side of the aluminum alloy, under the action of the structure and the glue, The decorative edge 1 and the plastic case back shell are bonded to fix the decorative edge (as shown in Figure 4).

The above information disclosed in this Background section is only for enhancement of understanding of the background of the present disclosure, and thus it may include information that does not constitute the prior art known to those of ordinary skill in the art.

technical problem

Although the above method satisfies the assembly requirements, it does not solve the dimensional tolerance problem of the rear case produced by the injection molding process (the tolerance of the arrow length in Fig. 1 still exists).

Technical solution

In order to solve the above problems, the present invention adopts an external correction method to provide a method for reducing the length tolerance in the rear shell of the wristband. This method does not require adding additional materials, and only needs to be made on the existing components. The structural changes can achieve the effect of reducing the length tolerance in the rear shell and can be placed for subsequent loosening.

The technical solution of the present invention is as follows:

A method of reducing the length tolerance in a rear casing of a bracelet, the bracelet comprising a plastic back shell and a decorative edge for mounting the strap, the method comprising the steps of:

SS1, injection molding the back shell of the material member, the left and right ends of the upper and lower sides of the rear shell of the plastic member are respectively provided with straight sockets, the depth of the straight socket is 2-4 mm;

SS2, the decorative edge is an aluminum alloy decorative edge, and the CNC program processes two matching columns on the decorative edge of the aluminum alloy; the two matching columns are located on the same side of the decorative side of the aluminum alloy; Processing two matching columns, do not replace the clamp; the relative position dimensional tolerance between the two matching columns is ± 0.02 mm;

SS3, the mating column of the decorative edge of the aluminum alloy is matched with the straight socket of the rear shell of the plastic component, and the matching post and the straight jack have an interference fit.

Further, in the step SS1, the depth of the straight jack is 3 mm.

In the step 2, the relative position dimensional tolerance between the two mating columns is ±0.01 mm.

Further, in the step SS3, the one-side interference of the interference fit is 0.025 mm.

Further, in the step SS1, the upper and lower sides of the plastic case rear case are provided with a plurality of bone positions; in the step SS2, after the two matching columns are processed by the CNC, the two fits are performed A plurality of bone bit grooves are machined between the columns, the positions of the bone bit grooves corresponding to the bone positions.

Beneficial effect

The method does not require the addition of additional materials, and only requires modification of the process and structure on the existing components, so that the effect of reducing the length tolerance in the rear casing can be achieved, and the subsequent looseness can be placed.

DRAWINGS

The above and other objects, features and advantages of the present invention will become more apparent from the embodiments of the invention.

Figure 1 is a schematic illustration of a prior art backshell.

2 is a schematic view of a decorative side of an aluminum alloy of the prior art.

Fig. 3 is a schematic view showing the arrangement of bone sites on the back shell of the prior art.

4 is a schematic view of a prior art aluminum alloy trim and back shell assembly.

Fig. 5 is a straight insertion hole provided on the rear case of the plastic member of the present invention.

Fig. 6 is a mating column provided on the decorative side of the aluminum alloy of the present invention.

Fig. 7 is a view showing a plurality of bone positions provided on the rear case of the plastic member of the present invention.

Fig. 8 is a bone groove provided on the decorative side of the aluminum alloy of the present invention.

Figure 9 is an assembled view of the mating post of the decorative side of the aluminum alloy of the present invention and the straight socket on the rear case.

Figure 10 is an assembled view of the bone bit groove on the decorative side of the aluminum alloy of the present invention and the bone position on the rear case.

Embodiments of the invention

Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be embodied in a variety of forms and should not be construed as being limited to the examples set forth herein; rather, these embodiments are provided to make the invention more comprehensive and complete, and the embodiments of the example embodiments are fully conveyed. To those skilled in the art. The drawings are only schematic representations of the invention and are not necessarily to scale. The same reference numerals in the drawings denote the same or similar parts, and the repeated description thereof will be omitted.

Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are set forth However, one skilled in the art will appreciate that the technical solution of the present invention may be practiced and one or more of the specific details may be omitted, or other methods, components, devices, steps, etc. may be employed. In other instances, well-known structures, methods, apparatus, implementations, or operations are not shown or described in detail to avoid obscuring aspects of the invention.

Due to the limitations of the injection molding process, the tolerance of ±4 mm in the length dimension of the plastic part (back shell) cannot be substantially reduced or eliminated.

As shown in Figures 5, 6 and 9, two straight sockets 3 are provided on the rear shell of the plastic part, and two mating columns 4 are correspondingly arranged on the decorative side of the aluminum alloy.

The depth of the straight jack is 2-4 mm, preferably 3 mm. According to the injection molding process, after the injection molding, the distance dimension of the straight jacks on both sides of the plastic part also has a tolerance of ±4 mm.

Two mating columns are correspondingly arranged on the side of the decorative side 1 of the aluminum alloy. The aluminum alloy is made of 6063 material and has a high hardness. The aluminum alloy is machined with two matching columns by CNC. During processing, since the two matching columns are on the same side of the decorative side 1 of the aluminum alloy, there is no need to change the fixture, thus avoiding the error of the fixture. The two mating columns are changed from CNC to one-time forming, and the relative positional dimension tolerance of the two mating columns 4 after forming is ±0.01 mm.

The matching column 4 and the straight jack 3 have an interference fit, and the single side has an interference of 0.025 mm. When the rear shell of the plastic part is matched with the decorative edge of the aluminum alloy, since the relative position of the matching column on the aluminum alloy is relatively accurate, the strength is stronger than that of the plastic part, so when the matching column and the straight socket are matched, when the inner shell is injection molded When the error is large, the plastic case back shell will be deformed, and the two aluminum alloy decorative sides on both sides of the plastic case back side will correct the relative positions of the two straight jacks. This reduces the tolerances that plastic parts can produce during injection molding.

At the same time, as shown in Figs. 7, 8, and 10, in order to prevent looseness after the fitting, a plurality of bone bit grooves 6 are washed out on the same side of the aluminum alloy decorative side and the mating column, and the bone bit grooves 6 are glued. Correspondingly, a plurality of bone positions are provided on the side of the rear shell corresponding to the bone bit groove 6, and cooperate with the bone bit groove 6. When the back part of the plastic part is matched with the decorative edge of the aluminum alloy, the glue in the bone bit groove will adhere to the bone position on the plastic part to avoid deformation and stress release in the later stage.

The bone groove can correspond to the number of bone sites, for example, five.

The number of bone groove can also be more than the number of bone sites. For example, when the bone position is 5, in addition to setting a bone groove for each bone position, bone can be placed at the corresponding position between each two bone positions. The bit groove, as shown in Figures 7 and 8, provides five bone bit slots when there are five bone sites.

Finally, it should be noted that the above embodiments are merely illustrative of the technical solutions of the present invention, and are not intended to be limiting; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art will understand that The technical solutions described in the foregoing embodiments may be modified, or some or all of the technical features may be equivalently replaced; and the modifications or substitutions do not deviate from the technical solutions of the embodiments of the present invention. range.

Claims

A method of reducing the length tolerance in a rear casing of a bracelet, the bracelet comprising a plastic back shell and a decorative edge for mounting the strap, the method comprising the steps of:

SS1, injection molding the back shell of the material member, the left and right ends of the upper and lower sides of the rear shell of the plastic member are respectively provided with straight sockets, the depth of the straight socket is 2-4 mm;

SS2, the decorative edge is an aluminum alloy decorative edge, and the CNC program processes two matching columns on the decorative edge of the aluminum alloy; the two matching columns are located on the same side of the decorative side of the aluminum alloy; Processing two matching columns, do not replace the clamp; the relative position dimensional tolerance between the two matching columns is ± 0.02 mm;

SS3, the mating column of the decorative edge of the aluminum alloy is matched with the straight socket of the rear shell of the plastic component, and the matching post and the straight jack have an interference fit.
A method of reducing length tolerance in a rear casing of a wristband according to claim 1, wherein in said step SS1, said straight socket has a depth of 3 mm.
The method for reducing the tolerance of the length of the rear casing of the bracelet according to claim 1, wherein in the step SS2, the relative position dimensional tolerance between the two mating columns is ±0.01 mm. .
A method for reducing the tolerance of the length of the rear casing of the bracelet according to claim 1, wherein in the step SS3, the one-side interference of the interference fit is 0.025 mm.
The method for reducing the tolerance of the length of the rear casing of the bracelet according to claim 1, wherein in the step SS1, the upper and lower sides of the rear shell of the plastic member are provided with a plurality of bone positions; In step SS2, after the two matching columns are processed by the CNC, a plurality of bone bit grooves are processed between the two matching columns, and the position of the bone bit grooves corresponds to the bone position.
A method for reducing the tolerance of the length of the rear shell of the bracelet according to claim 5, wherein in the step SS2, the glue is glued in the bone groove corresponding to the bone position.