Process of forming a gasket directly on workpiece, using a mold clamped to the workpiece

• US 5,686,032 A
• Filed: 11/15/1994
• Issued: 11/11/1997
• Est. Priority Date: 11/17/1993
• Status: Expired due to Term

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Miwa, Hiroyuki, Mizobe, Tatsuya, Sumiyoshi, Masayuki
• Primary Examiner(s): ORTIZ, ANGELA Y
• Application Number:
  US08/340,414
• Time in Patent Office: 1,092 Days
• Field of Search: 264/250, 264/255, 264/259, 264/266, 264/102, 264/40.1, 264/40.3, 264/267
• US Class Current: 264/40.3
• CPC Class Codes: B29C 2045/14459 injecting seal elements
• CPC Class Codes: B29C 2945/76006 Pressure
• CPC Class Codes: B29C 2945/76076 duration
• CPC Class Codes: B29C 2945/76307 hydraulic fluids
• CPC Class Codes: B29C 2945/76381 Injection
• CPC Class Codes: B29C 2945/76498 Pressure
• CPC Class Codes: B29C 2945/76591 volume
• CPC Class Codes: B29C 2945/76765 Moulding material
• CPC Class Codes: B29C 2945/76785 hydraulic fluids
• CPC Class Codes: B29C 2945/76859 Injection
• CPC Class Codes: B29C 45/14336 Coating a portion of the article, e.g. the edge of the article B29C45/14573 and B29C45/14598 take precedence
• CPC Class Codes: B29C 45/2608 Mould seals
• CPC Class Codes: B29C 45/34 having venting means
• CPC Class Codes: B29C 45/768 Detecting defective moulding conditions B29C45/84 takes precedence
• CPC Class Codes: B29C 45/77 of velocity or pressure of moulding material
• CPC Class Codes: B29K 2083/005 LSR, i.e. liquid silicone rubbers, or derivatives thereof
• CPC Class Codes: F16J 15/108 Special methods for making a non-metallic packing

Abstract

A process and an apparatus for forming a gasket directly on a workpiece having a joining surface which has an annular gasket-fixing groove, wherein a mold having a gasket-forming groove which cooperates with the gasket-fixing groove to define a cavity for forming the gasket is clamped to the joining surface of the workpiece, and a material is injected into the cavity through an injection passage which is formed through the mold and which communicates with the gasket-forming groove. The material is cured into the gasket, and the mold is removed from the workpiece. The mold may have two elastic sealing members disposed on inner and outer sides of the gasket-forming groove, respectively, so as to extend along the gasket-forming groove, and provide pressure-tight sealing of the cavity when the body is placed on the workpiece such that the sealing members are held in elastic pressure-tight contact with the joining surface.

Claims

1. A process of forming a gasket directly on a workpiece having a joining surface which has an annular gasket-fixing groove, comprising the steps of:

preparing a mold having a gasket-forming groove which cooperates with said gasket-fixing groove to define a cavity for forming said gasket, said mold further having a fluid passage;

clamping said mold to said joining surface of said workpiece;

injecting a material for the gasket into said cavity through an injection passage which is formed through said mold and which communicates with said gasket-forming groove;

curing said material injected in said cavity;

removing said mold from said workpiece;

attaching inner and outer elastic tubes to a body of said mold such that said inner and outer elastic tubes communicate with said fluid passage and are disposed on inner and outer sides of said gasket-forming groove, respectively, so as to extend peripherally along said gasket-forming groove, said step of clamping said mold comprising clamping said body of said mold to said joining surface of said workpiece such that said inner and outer elastic tubes are held in elastic pressure-tight contact with said joining surface of said workpiece;

connecting a pressurized-fluid supply device to said fluid passage of said body, for supplying said elastic tubes with a pressurized fluid;

detecting a pressure of said pressurized fluid in said elastic tubes;

detecting an injection pressure of said material; and

controlling at least one of said pressurized-fluid supply device and a material feeding device for injecting said material into said cavity through said injection passage, such that the detected pressure of said pressurized fluid and the detected injection pressure of said material increase, during an operation of said material feeding device, so as to maintain a predetermined relationship therebetween without leakage of said material from said cavity.

2. A process according to claim 1, further comprising the steps of:

detecting an amount of injection of said material into said cavity through said injection passage; and

determining whether the detected injection pressure of said material and the detected amount of injection of said material into said cavity satisfy a predetermined relationship, and providing an indication of abnormality associated with the injection of said material if said predetermined relationship is not satisfied.

3. A process according to claim 1, further comprising the steps of:

measuring an injection time of said material which has passed after an operation of injection of said material into said cavity through said injection passage is started; and

determining whether the detected injection pressure of said material and the measured injection time satisfy a predetermined relationship, and providing an indication of abnormality associated with the injection of said material if said predetermined relationship is not satisfied.

4. A process according to claim 1, further comprising the steps of:

detecting an amount of injection of said material into said cavity through said injection passage;

measuring an injection time of said material which has passed after an operation of injection of said material into said cavity is started; and

determining whether the detected amount of injection of said material and the measured injection time satisfy a predetermined relationship, and providing an indication of abnormality associated with the injection of said material if said predetermined relationship is not satisfied.