Out-of-balance control for washing machine
AssigneeU.S. Controls Corporation
InventorsRichard G. Smith, Kenyon A. Hapke, Spencer C. Schantz
Life of this patent
Estimating the term…
Abstract
An acceleration sensitive switch for use in detecting an out-of-balance condition on a residential washing machine, or the like, uses a pendulum activated switch wherein the pendulum is biased against an energy absorbing stop by a predetermined threshold force corresponding to the desired switching acceleration. The geometry of the spring and pendulum are such that the restoring force decreases as the pendulum moves to activate the switch providing positive switching action and permitting simple calibration of the unit.
Claims12
An out-of-balance control for detecting lateral housing motion comprising:
- a weight mounted for movement in a lateral direction between a rest position and an activation position to move independently of the housing in response to lateral housing motion;
- an electrical switch positioned at the activation position so as to be actuated when the weight has moved to the activation position;
- a stop located at the rest position to contact the weight when the weight has moved to the rest position;
- and
- a spring attached to the weight for biasing the weight toward the stop with a threshold force that decreases as the weight moves away from the stop so that in the absence of other lateral forces, a non-zero predetermined acceleration of the housing in the lateral direction is required to cause the weight to move to the activation position to activate the switch.
An out-of-balance control for detecting lateral motion of a housing comprising:
- a weight mounted for movement in a lateral direction with respect to the housing between a rest position and an activation position;
- an electrical switch positioned at the activation position so as to be actuated when the weight has moved to the activation position;
- a stop located at the rest position to contact the weight when the weight has moved to the rest position;
- and
- a spring attached to the weight for biasing the weight against the stop with a threshold force so that in the absence of other lateral forces, a non-zero predetermined acceleration of the device in the lateral direction is required to cause the weight to move to the activation position to activate the switch;
- wherein the weight is mounted on a pivoting arm to move in the lateral direction about a fulcrum point on the housing, and wherein the spring is attached in tension between a first mounting point near the weight and a second mounting point on the housing between the weight and the fulcrum point to draw the arm toward the fulcrum point.
A method of calibrating an out-of-balance control for detecting lateral housing motion, the control including a weight mounted for movement in a lateral direction with respect to the housing between a rest position and an activation position, an electrical switch positioned at the activation position so as to be actuated when the weight has moved to the activation position, a stop located at the rest position to contact the weight when the weight has moved to the rest position, a spring attached between the weight and a spring mounting point fixed with respect to the housing for biasing the weight toward the stop in the absence of other lateral forces the spring providing a force of biasing of the weight toward the stop that decreases as the weight moves away from the stop, the method comprising the steps of:
- a) displacing the weight by a predetermined distance from the stop position in the absence of other lateral forces;
- and
- b) adjusting the spring biasing to a predetermined biasing force.
Dependencies are inferred from the claim text.