Strain relief collar for accessories associated with mobile device and method of making

The present invention discloses a strain relief collar for use with an accessory associated with a mobile device and its method of making. The first step is the making of an outer molded body having an engagement portion with a cutout. The second step is inserting a cord into the outer molded body. The third step is the forming of an inner molded body having a hooking portion extending outward from the periphery thereof and beyond the cutout for engaging with an accessory. The present invention also discloses another strain relief collar for use with another accessory associated with a mobile device and its method of making. The first step is connecting the cord to an electrical component associated with the accessory. The second step is the forming of an inner molded body. The third step is the forming of an outer molded body.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a strain relief collar for use with accessories associated with a mobile device and its method of manufacture, in particular to a strain relief collar which has a smooth outer periphery, prevents excessive bending of a cord and inhibits the cord from being pulled off a connection.

2. Description of the Related Art

Referring toFIG. 1, an accessory associated with a mobile device comprises a microphone1having two earphones2and a wire3for cooperation with a plug4connected. Such an accessory suffers a problem, namely, the wire3attached to a circuit board (not shown) of the microphone1can be easily detached if the wire3is accidentally pulled with respect to the microphone1. Another problem is that an excessive bending stress normally occurs between the microphone1and the wire3when the wire3is overly twisted. As a result, the wire3also gets detached from the circuit board, causing a broken circuit.

Referring toFIG. 2, the microphone1further includes a strain relief collar5which is adapted to prevent excessive bending of the wires3. Nevertheless, such a strain relief collar5will not effectively prevent wires3from being pulled off the circuit board accidentally-in that the strain relief collar5is made of soft material and the wires3are only gripped by the strain relief collar5. Furthermore, since the strain relief collar5has a plurality of recessed portions, dirt can easily accumulate in the recessed portions.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide a strain relief collar for accessories associated with a mobile device which overcomes the disadvantages of the prior arts.

It is another object of the present invention to provide a strain relief collar and methods for making the same.

It is also another object of the present invention is to provide a strain relief collar which cooperates with a wire having a connection with a circuit board of an accessory for preventing easy detachment of the wire from the circuit board if the wire is accidentally pulled with respect to the circuit board, and methods for making the same.

It is yet another object of the present invention is to provide a strain relief collar which prevents an excessive bending occurred between the wire and the accessory and methods for making the same.

It is a further object of the present invention is to provide a strain relief collar with a smooth outer surface so as to prevent accumulation of dirt and methods for making the same.

Thus, the present invention provides a method for making a strain relief collar, in which the method comprises making of an outer molded body as the first step; inserting a cord into the outer molded body as the second step; forming of an inner molded body as the third step.

The present invention also discloses another method of making, in which the first step is connecting the cord to an electrical component associated with the accessory; the second step is the forming of an inner molded body and the third step is the forming of an outer molded body.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 3is a flowchart showing steps for making a strain relief collar for an accessory90in accordance with a first embodiment of the present invention. In this exemplary embodiment, the accessory90is a microphone for a mobile device.

The first step in the practice of this invention is the making of an outer molded body10. The outer molded body10is injection molded from thermoplastic elastomer (TPE) and has a hardness of 70 A.

Referring toFIGS. 4 and 5, the outer molded body10is of horn-shaped, with an end which progressively becomes wider at an opposite end and defines an extended portion13at a narrower end. The outer molded body10also includes a recessed engagement portion11formed at a wider end thereof and on the peripheral wall thereof, there is formed a cutout12. Furthermore, the extended portion13has a smooth outer periphery for preventing the formation of dirt therein. In addition, the extended portion13includes a bore14in communication with the engagement portion11.

The second step in the practice of this invention is inserting a cord20into the bore14until the cord20exposes outside the engagement portion11, as seen inFIG. 6.

The third step in the practice of this invention is the forming of an inner molded body30, in which the inner molded body30is injection molded from thermoplastic elastomer (TPE) and has a hardness of 100 A which is harder than the outer molded body but softer than the accessory90.

Referring toFIGS. 7 through 9, the inner molded body30is injection molded in the engagement portion11such that the cord20and the outer molded body10are connected by the inner molded body30. Furthermore, the inner molded body30defines a supporting portion34attached with the engagement portion11. The supporting portion34can prevent excessive bending of the cord20which can result a broken circuit. Additionally, the portion of the cord20exposed outside the outer molded body10is partially circumscribed by the inner molded body30and partially left exposed.

As also seen fromFIGS. 7 through 9, a hooking portion31, an engaging slot32and two locking slots33are formed by the inner molded body30for engagement with the accessory90. The hooking portion31extends outward from the periphery thereof and beyond the cutout12. The engaging slot32and the locking slots33extend inward from the inner molded body30, but with the former extending in an opposite direction to the latter. Additionally, the engaging slot32is disposed adjacent to the hooking portion31.

The finished product of the strain relief collar is best shown inFIG. 9and is readily engagable with the accessory90, which is the microphone (as seen inFIG. 10). The accessory90is fixed to the inner molded body30by engaging with the hooking portion31, the engaging slot32and the locking slots33.

FIG. 11is a flowchart showing steps for making a strain relief collar for an accessory91associated with a mobile device in accordance with a second embodiment of the present invention. In this exemplary embodiment, the accessory91for a mobile device is a connector plug.

Referring toFIG. 12, at the first step in the practice of this invention, the cord20is connected to an electrical component (not numbered), i.e. a terminal platform.

At the second step in the practice of this invention, an inner molded body40is injection molded from thermoplastic elastomer (TPE) and which has a hardness of 100 A, which has less hardness than the electrical component.

Referring toFIGS. 13 and 14, the cord20and the electrical component are partially surrounded by the inner molded body40such that the cord20and the electrical component are firmly engaged with each other by the inner molded body40. The inner molded body40also includes an engaging slot41and a plurality of arcuate locking slots43extending transversely therethrough. Furthermore, the inner molded body40defines a supporting portion44circumscribing the outer periphery of the cord20for preventing excessive bending of the cord20which can result a broken circuit.

At the third step in the practice of this invention, an outer molded body50which has a hardness of 70 A is injection molded from thermoplastic elastomer (TPE). Referring toFIGS. 15 and 16, the inner molded body40is completely surrounded by the outer molded body50. The cord20and the electrical component are partially enclosed by the outer molded body50. The outer molded body50includes a terminating edge54engaged with the electrical component for secure attachment to the inner molded body40, an engaging column51disposed in the engaging slot41and a plurality of locking members53disposed in the corresponding locking slots43. Accordingly, the outer molded body50is firmly connected to the inner molded body40.

As also seen inFIG. 15, the outer molded body50includes an extended portion55extending axially corresponding to the supporting portion44. The extended portion55has a smooth outer periphery for preventing the formation of dirt therein and an orifice56which allows the portion of the cord20disposed therein to be supported and thereby prevent excessive bending of the cord20.

Referring toFIG. 17, the extended portion55includes an indentation57formed around the inner periphery thereof. The indentation57extends from an end thereof until it reaches the orifice56.

Thus, in view of the embodiments illustrated herein, one advantage is the provision of the inner molded body30,40and the outer molded body10,50which are formed of the same material. As such, the inner molded body30,40and the outer molded body10,50can be tightly engaged with each other.

Another advantage is that the provision of the inner molded body30,40for inhibiting the cord20from being easily pulled off the accessory90,91.

Yet another advantage of the invention is the provision of the extended portion13,55for preventing dirt from being easily accumulated thereto.

While the specific embodiments have been illustrated and described, numerous modifications come to mind without significantly departing from the spirit of invention and the scope of invention is only limited by the scope of accompanying claims.