Apparatus for selectively varying keyboard switching force

• US 5,220,318 A
• Filed: 08/20/1990
• Issued: 06/15/1993
• Est. Priority Date: 12/22/1988
• Status: Expired due to Term

• Current Assignee: Ampex Corporation (Delta Information Systems, Inc.)
• Original Assignee: Ampex Corporation (Delta Information Systems, Inc.)
• Inventors: Staley, Darrell S.
• Primary Examiner(s): Yusko, Donald J.
• Assistant Examiner(s): ZIMMERMAN, BRIAN A
• Application Number:
  US07/570,072
• Time in Patent Office: 1,030 Days
• Field of Search: 341/34, 341/32, 84/DIG. 7, 335/126, 335/131, 400/477, 400/479.2, 400/480, 400/481, 400/490, 400/495, 400/495.1, 400/491.2, 178/17 C, 178/101, 200/5 A, 361/187, 361/191, 361/144
• US Class Current: 341/34
• CPC Class Codes: B41J 5/26 Regulating touch, key dip or stroke, or the like
• CPC Class Codes: H01H 2215/05 electromechanical
• CPC Class Codes: H01H 2221/04 magnetic
• CPC Class Codes: H01H 2227/034 Regulation of operating force

Abstract

Apparatus for adjusting the key activating force or "touch" for a keyboard or for one or more function key groups on that keyboard to the needs of any individual operator.

Claims

1. A keyboard array including a plurality of switch assemblies, each switch assembly comprising a switch body, a member supporting the switch body to accommodate movement between first and second spatial positions, and apparatus for controlling the amount of force necessary to cause one of said switch assemblies to move from the first to the second spatial positions, said apparatus comprising:

spring means positioned between the switch body and the supporting member for exerting a first biasing force against the switch body toward said first position;

magnetic permeable means on the switch body;

a multi-turn coil for generating a magnetic field aligned to exert on said magnetic permeable means a second biasing force opposing said first biasing force; and

power means for supplying an electrical current to said coil for generating said magnetic field to selectively vary said second biasing force, thereby controlling the amount of force necessary to cause the energized switch assembly to move from the first to the second spatial position.

2. A keyboard array including a plurality of switch assemblies, each switch assembly comprising a switch body, a member supporting the switch body to accommodate spatial movement between first and second spatial positions, and apparatus for selectively controlling the amount of force required by one of said switch assemblies to move from the first to the second spatial positions, said apparatus comprising:

spring means between the switch body and the supporting member and exerting a biasing force against the switch body toward said first position;

a magnetically permeable sleeve mounted on the switch body;

a multi-turn coil surrounding at least a portion of the sleeve, said coil when energized generating a magnetic field for exerting an attractive force on said sleeve opposing said biasing force; and

power means for supplying an electrical current to said coil to energize same, said power means being operative to selectively vary said attractive force of said magnetic field.

3. A keyboard array including a plurality of switch assemblies, each switch assembly comprising a switch body, a member supporting the switch body for movement between first and second body positions, and apparatus to drive each of said switch assemblies from the first to the second body positions with equal force, said apparatus comprising:

spring means between the switch body and the supporting member and providing a first force against the switch body and biasing same toward said first position;

a magnetically permeable sleeve mounted on the switch body;

a single multi-turn coil surrounding at least a portion of each sleeve of the array, said coil being operative to generate a magnetic field; and

at least one electrical power input assembly to supply an electrical signal to each coil to energize same, the magnetic field generated by each coil being interactive with the associated sleeve for generating a second force in a direction opposite to and of magnitude less than said first force, said second force being equal for each switch assembly, the power means being operative to selectively vary said second force and thereby correspondingly varying the effect of said first force of the spring.

4. A keyboard array including at least one cluster of switch assemblies, each switch assembly of the cluster comprising a switch body, a member supporting the switch body for movement between first and second body positions, and apparatus to drive each of said switch assemblies of the cluster from the first to the second second body positions, said apparatus comprising:

a spring between the switch body and the supporting member and providing a first force resisting movement of the switch body in a first direction from the second to the first positions,

a magnetically permeable sleeve mounted on the switch body;

a single multi-turn coil surrounding at least a portion of each sleeve of the cluster, said coil when energized being operative to generate a magnetic field; and

at least one electrical power input assembly to supply an electrical signal to each coil to energize same, the magnetic field generated by each coil being interactive with the associated sleeve for generating a second force in a direction opposite to and of magnitude less than said first force, said second force being equal for each switch assembly, the power means being operative to selectively vary said second force and thereby correspondingly varying the effect of said first force of the spring in resisting movement of the switch body from the first to the second body positions.

5. A keyboard array including a plurality of switch assemblies, each switch assembly comprising a switch body, a member supporting the switch body for movement along an axis generally perpendicular to the support member and between first and second relatively fixed body positions, a cap mounted on the switch body, biasing means between the support member and the cap to apply a bias force against the switch body to move same to the first body position, and apparatus to drive each of said switch assemblies from the first to the second body positions, said apparatus comprising:

a magnetically permeable sleeve mounted on the switch body;

a single multi-turn coil surrounding at least a portion of the sleeve, said coil when energized being operative to generate a magnetic field; and

an electrical power input assembly to supply an electrical signal to the coil to energize same, the magnetic field generated by each coil being interactive with the associated sleeve and exerting a pull on same toward the second body position and thereby decreasing the bias force of the biasing means, the power means being operative to selectively vary the magnitude of said pull on the sleeve and thereby correspondingly to vary the effect of said bias force in resisting movement of the switch body from the first to the second body positions.