# US 4,391,107 A · Spiral gyrator for washing machines

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- Number: US 4,391,107 A
- Document ID: US4391107A
- Status: Granted
- Kind: A
- Application number: 06/265,936
- Filed: 1981-05-21
- Granted: 1983-07-05
- Earliest claimed: 1981-05-21
- Inventors: George M. Gibson
- Web page: https://patentgrep.com/patent/US4391107A

## CPC

- D06F 13/02: wherein the agitator has an oscillatory rotary motion only
- D06F 17/10: Impellers
- D06F: LAUNDERING, DRYING, IRONING, PRESSING OR FOLDING TEXTILE ARTICLES

## Abstract

A spiral gyrator to be driven unidirectionally at a rate within the normal range for drying by spinning has a spiral strip about a base and upwardly on a central, upright post. The direction of the spiral is reversed for a turn near the top of the post. The first part of the spiral strip farthest from the center on the base has a plurality of spaced slots through it for creating radial jets of washing fluid to move wash rapidly in a pulsating manner. The rotative driving apparatus for the gyrator is simplified, and the reverse turn of the spiral strip near the top of the post prevents wash from being forced over the top of the post while the rotation of the gyrator is reversed and the tub of the washing machine is accelerating to a spinning rate.

## Claims

### Claim 1

A washing machine comprising:
a tub having a bottom and a substantially vertical wall for enclosing a space to contain wash,
a gyrator having a base and a driving post, said base subtending a substantial portion of said bottom, said base having an outer circumferential portion and an inner upper portion shaped substantially as a frustum of a cone, the base of the cone being parallel with said bottom and said outer portion extending outwardly therefrom, said driving post extending coaxially upwardly from the truncated end of said inner portion of said base,
a driving surface comprising a spiral ridge having one end positioned substantially circumferentially on the upper surface of said outer circumferential portion and extending from said one end gradually inwardly and upwardly in one circumferential direction on the surface of said inner portion of said base to said truncated end thereof and continuing in said one circumferential direction like an expanded helical screw thread upwardly about said driving post to an upper intermediate region of said post where said ridge gradually reverses in circumferential direction to form at least one helical turn of opposite direction near the upper end of said driving post, the ends of said driving surface having gradual and smooth contours, and
unidirectional driving means connected to said driving post to rotate said gyrator about said axis thereof.

### Claim 2 (depends on 1)

A washing machine as claimed in claim 1 wherein said ridge on said upper surface of said peripherial portion of said base has a plurality of spaced slots as channels thereacross to provide radial jets of washing fluid as said gyrator is rotated unidirectionally.