Method of manufacturing a screw connector

• US 6,001,294 A
• Filed: 08/11/1997
• Issued: 12/14/1999
• Est. Priority Date: 11/24/1992
• Status: Expired due to Term

• Current Assignee: Yazaki Corporation
• Original Assignee: Yazaki Corporation
• Inventors: Yamamoto, Masayuki, Inaba, Shigemitsu
• Primary Examiner(s): Silbaugh, Jan H
• Assistant Examiner(s): Lee, Edmund H.
• Application Number:
  US08/907,998
• Time in Patent Office: 855 Days
• Field of Search: 264/263, 264/275, 264/269, 264/278, 425/125, 425/129.1
• US Class Current: 264/278
• CPC Class Codes: F16B 37/048 Non-releasable devices F16B37/044, F16B37/045 and F16B37/06 take precedence
• CPC Class Codes: Y10S 411/903 Resinous exterior

Abstract

A screw connector is manufactured with an injection metal mold. The screw connector includes a connector main body and a nut embedded in the connector main body. An axis of the nut extends in a forward and backward direction of the connector main body. The screw connector further includes a first opening located on a front side of the nut for receiving by a bolt of a mating connector and a first columnar space located on a rear side of the nut for receiving a distal end portion of the bolt. The method includes three steps. The first step is setting the metal mold in such a state that the nut is held by a front projection portion and a rear projection portion. This front projection portion projects rearwardly and has a small diameter portion and a portion having larger diameter than said small diameter portion. This rear projection portion projects forwardly so as to be in contact with a rear end face of said nut. The second step is injecting a melted resin in said metal mold. The third step is separating a resin molded product from said metal mold.

Claims

1. A method of manufacturing a screw connector which comprises a connector body, a threaded nut embedded in said connector body and having a thread hole with a thread diameter, a front end face, a rear end face and an axis extending in forward and rearward directions of said connector body, a bolt insertion hole provided in front of said front end face of said nut to an exterior of said connector main body, for a bolt of a mating connector to be inserted therethrough to be screwed into the nut, and a tubular cap portion provided behind said nut, for accommodating a distal end portion of said bolt, said method comprising the steps of:

providing a metal mold for injection molding, a front mold and a plurality of rear molds, said front mold having (i) a small diameter portion with a rear end part of equal diameter to said thread diameter of said nut, (ii) an intermediate diameter portion being larger than said thread diameter of said nut, (iii) a large diameter portion and (iv) a step defined by the small diameter portion and the intermediate diameter portion, each rear mold of said plurality of rear molds having an upper end portion;

inserting said small diameter portion into said thread hole of said nut so that said rear end part of said small diameter portion projects from said nut in the rearward direction and said step is brought into contact with a portion of said front end face of said nut to prevent said nut from moving forwardly;

bringing said upper end portion of each rear mold of said plurality of rear molds into contact with a corresponding portion of said rear end face of said nut so that said nut is held by said step of said front mold and said upper end portion of each rear mold of said plurality of rear molds to prevent said nut from moving rearwardly and sidewardly;

injecting a molten body of a resin into the metal mold to form said connector body such that (i) said bolt insertion hole is formed by said intermediate diameter portion of said front mold, (ii) said tubular cap portion is molded from inside by said small diameter portion of said front mold and said plurality of rear molds, said tubular cap portion being closed in a rear direction, and said plurality of rear molds forming a notched portion extending from a part of an outer circumference of a rear end portion of said nut to an exterior of said connector main body, and (iii) said connector body is molded with said nut embedded between said bolt insertion hole and said tubular cap portion; and

separating said metal mold, said front mold and said plurality of rear molds from said connector body.

2. The method of claim 1, wherein said rear molds comprise a triangular member,

and wherein the injecting step includes forming said notched portion by the triangular member so that said notched portion is provided through said tubular cap portion.

3. The method of claim 2, wherein the triangular member has a triangular positioning groove and wherein the holding step includes holding a rear end corner of said nut with said triangular member having said triangle positioning groove.

4. The method of claim 1, wherein the providing step includes

arranging another mold of a pin form in parallel with said front mold and wherein the injecting step includes forming a groove by said another mold such that said groove is formed outside said bolt insertion hole of the connector body.

5. The method of claim 1, wherein

each rear mold of said plurality of rear molds has an arcuate portion disposed on said upper end portion thereof and

wherein the injecting step includes molding an outside of the tubular cap portion by said arcuate portion.

6. The method of claim 1, wherein each rear mold of the plurality of said rear molds has an arcuate step portion disposed on said upper end portion thereof and

wherein the injecting step includes forming a groove about said tubular cap portion by said arcuate step portion.

7. The method of claim 1, wherein said small diameter portion is non-threaded.

8. A method of manufacturing a screw connector which comprises a connector body, a threaded nut embedded in said connector body and having a thread hole with a thread diameter, a front end face, a rear end face and an axis extending in forward and rearward directions of said connector body, a bolt insertion hole provided in front of said front end face of said nut to an exterior of said connector main body, for a bolt of a mating connector to be inserted therethrough to be screwed into the nut, and a tubular cap portion provided behind said nut, for accommodating a distal end portion of said bolt, said method comprising the steps of:

providing a metal mold for injection molding, a front mold, another mold of a pin form and a plurality of rear molds, said front mold having (i) a small diameter portion with a rear end part of equal diameter to said thread diameter of said nut, (ii) an intermediate diameter portion being larger than said thread diameter of said nut, (iii) a large diameter portion and (iv) a step defined by the small diameter portion and the intermediate diameter portion, each rear mold of said plurality of rear molds having an upper end portion;

inserting said small diameter portion into said thread hole of said nut so that said rear end part of said small diameter portion projects from said nut in the rearward direction and said step is brought into contact with a portion of said front end face of said nut to prevent said nut from moving forwardly;

bringing said another mold into contact with a part of an outer circumferential face of said nut to prevent said nut from moving sidewardly;

bringing said upper end portion of each rear mold of said plurality of rear molds into contact with a corresponding portion of said rear end face of said nut so that said nut is held by said step of said front mold and said upper end portion of each rear mold of said plurality of rear molds to prevent said nut from moving rearwardly;

injecting a molten body of a resin into the metal mold to form said connector body such that (i) said bolt insertion hole is formed by said intermediate diameter portion of said front mold, (ii) said tubular cap portion is molded from inside by said small diameter portion of said front mold and said plurality of rear molds, said tubular cap portion being closed in a rear direction, and said plurality of rear molds forming a notched portion extending from a part of an outer circumference of a rear end portion of said nut to an exterior of said connector main body, (iii) an opening extending from said part of said outer circumferential face of said nut to said exterior of said connector body, (iv) said connector body is molded with said nut embedded between said bolt insertion hole and said tubular cap portion; and

separating said metal mold, said front mold and said plurality of rear molds from said connector body.

9. The method of claim 8, wherein each rear mold at said plurality of rear molds comprise a triangular member, and wherein the injecting step includes forming a notched portion by the triangular member so that said notched portion is provided through said tubular cap portion.

10. The method of claim 8, wherein each rear mold of the plurality of rear molds has an arcuate portion disposed on said upper end portion thereof and wherein the injecting step includes molding an outside of the tubular cap portion by said arcuate portion.

11. The method of claim 8, wherein each rear mold of the plurality of said rear molds has an arcuate step portion disposed on said upper end portion thereof and wherein the injecting step includes forming a groove about said tubular cap portion by said arcuate step portion.