Fabrication of seismic springs from sheets

• US 4,400,861 A
• Filed: 11/27/1981
• Issued: 08/30/1983
• Est. Priority Date: 11/27/1981
• Status: Expired due to Fees

• Current Assignee: OYO Geospace Corporation
• Original Assignee: OYO Instruments Inc.
• Inventors: Parker, Carl E.
• Primary Examiner(s): Husar, Francis S.
• Assistant Examiner(s): Jones, David B.
• Application Number:
  US06/325,138
• Time in Patent Office: 641 Days
• Field of Search: 29/527.2, 29/527.4, 29/173, 29/602, 29/602 A, 148/131, 148/132, 267/158, 267/161, 267/163
• US Class Current: 148/518
• CPC Class Codes: B21D 28/06 Making more than one part out of the same blank; Scrapless working
• CPC Class Codes: B21D 53/886 leaf springs
• CPC Class Codes: G01V 1/181 Geophones
• CPC Class Codes: Y10T 29/4908 Acoustic transducer
• CPC Class Codes: Y10T 29/49609 Spring making
• CPC Class Codes: Y10T 29/49799 Providing transitory integral holding or handling portion

Abstract

In accordance with the method of this invention, at least one sheet containing the spider springs is positioned in a novel preform fixture having internal parts constructed to simultaneously permanently preform each spring after the fixture is heat treated. The novel fixture for carrying out the preforming process of the invention on an etched sheet comprises a base plate having a number of columns extending vertically upwardly from the flat surface. The number of columns is equal to the number of springs on the sheet, and their disposition on the base corresponds to the disposition of the inner rings on the sheet. The outside diameter of a column is substantially equal to the outside diameter of an inner ring. An intermediate plate is provided defining a number of transverse bores equal to the number of columns. The diameter of each bore is substantially equal to the inside diameter of each outer ring so that the center of each column is also the center of each bore when the bottom surface of the intermediate plate is disposed on top of the base plate. A compression plate is disposed over the intermediate plate.

Claims

1. A method of preforming at least one sheet containing a plurality of seismometer spider springs, while the springs remain connected to the body of the sheet by tie tabs, comprising:

positioning the sheet in a preform fixture having internal parts constructed to simultaneously displace each inner ring of each spring relative to its outer ring by a predetermined distance; and

heat treating the fixture with the sheet therein, thereby causing the simultaneous preforming of the spider springs whereby each inner ring is permanently displaced from its outer ring.

2. The method of claim 1 and, while the preformed springs are still on the sheet, measuring the preform of the springs.

3. The method of claim 1 and, while the preformed springs are still on the sheet, plating the sheet with a conductive material.

4. The method of claim 1 wherein said tie tabs are diametrically opposed thereby facilitating the shearing of the springs from the sheet.

5. The method of claim 1 and etching into the sheet indexing and aligning holes before the sheet is loaded into the preform fixture.

6. A method of fabricating seismometer spider springs, comprising:

cutting out from a sheet of conductive metal a plurality of spider springs, each spring having an inner ring, an outer ring, and a plurality of arms interconnecting the inner and outer rings, and each outer ring remaining connected to the body of the sheet by tie tabs, and said sheet having a plurality of aligning and indexing holes;

positioning the sheet in a fixture having internal parts constructed to simultaneously displace each inner ring of each spring relative to its outer ring by a fixed predetermined distance; and

heat treating the fixture with the sheet therein, thereby causing the simultaneous preforming of the spider springs.