Tactile display apparatus

• US 4,871,992 A
• Filed: 07/08/1988
• Issued: 10/03/1989
• Est. Priority Date: 07/08/1988
• Status: Expired due to Term

• Current Assignee: Robert C. Petersen
• Original Assignee: Robert C. Petersen
• Inventors: Petersen, Robert C.
• Primary Examiner(s): Crosland, Donnie L.
• Application Number:
  US07/216,880
• Time in Patent Office: 452 Days
• Field of Search: 340/407,711,712,825.19, 434/112-115
• US Class Current: 340/407.1
• CPC Class Codes: G09B 21/003 using tactile presentation of the information, e.g. Braille displays

Abstract

Apparatus for providing a tactile display according to which a touch pin is selectively movable relative to a reference surface. An electromagnet distant from the reference surface has spaced poles of opposite, selectively reversible, polarity. A cam rotatable about an axis transverse to the reference surface has an integral permanent magnet with similarly spaced poles of opposite polarity equidistant from the axis of rotation. The cam is rotatable between an active position at which its respective poles are attacted to and positioned adjacent the poles of the electromagnet and an inactive position at which the reversed poles of the permanent magnet are attracted to and positioned adjacent the opposite poles of the electromagnet. A touch pin has a longitudinal axis transverse to the reference surface and includes a follower end engageable with the cam and a tip end distant from the follower end. The pin is movable on the cam between a first position raised above the reference surface when the cam is in the active position and a second position not projecting beyond the reference surface when the cam is in the inactive position. A plurality of touch pins and associated mechanisms can be combined into a matrix to form a tactile display unit and a plurality of such units can be provided in a console and electrically driven in an intelligent fashion to provide the user with various forms of tactile information.

Claims

1. Tactile display apparatus comprising:

a reference surface;

an electromagnet distant from said reference surface having first and second spaced poles of opposite, selectively reversible, polarity;

rotatable cam means proximate to said electromagnet having an axis of rotation transverse to said reference surface and including an integral permanent magnet with third and fourth spaced poles of opposite polarity equidistant from said axis of rotation, said cam means being rotatable between an active position at which said third and fourth poles, respectively, are attracted to and positioned adjacent said first and second poles, and an inactive position at which said fourth and third poles, respectively, are attracted to and positioned adjacent said first and second poles; and

a touch pin having a longitudinal axis transverse to said reference surface and including a follower end engageable with said cam means and a tip end distant from said follower end, said pin being movable on said cam means between a first position raised above said reference surface when said cam means is in said active position and a second position not projecting beyond said reference surface when said cam means is in said inactive position.

2. Tactile display apparatus as set forth in claim 1

wherein said reference surface is substantially planar;

and wherein said axis of rotation of said cam means and said longitudinal axis of said pin are both perpendicular to said reference surface.

3. Tactile display apparatus as set forth in claim 2

wherein said cam means is generally disk-shaped, has a planar base surface which is substantially parallel to said reference surface, and has an opposed contoured operative surface which ranges between an elevated region of maximum height above said base plane and a nominal region of minimum height above said base plane;

and

wherein said pin assumes said first position when said follower end is engaged with said elevated region and assumes said second position when said follower end is engaged with said nominal region.

4. Tactile display apparatus as set forth in claim 3 including:

means biasing said follower end into engagement with said operative surface.

5. Tactile display apparatus comprising:

a housing having a cavity therein and defining a reference surface and having an aperture therein for communication between the cavity and said reference surface, the aperture being sized and positioned to freely receive a touch pin therethrough;

an electromagnet fixed to said housing within the cavity distant from said reference surface, said electromagnet having first and second spaced poles of opposite, selectively reversible, polarity;

rotatable cam means proximate to said electromagnet having an axis of rotation transverse to said reference surface and including an integral permanent magnet with third and fourth spaced poles of opposite polarity equidistant from said axis of rotation, said cam means being rotatable between an active position at which said third and fourth poles, respectively, are attracted to and positioned adjacent said first and second poles and an inactive position at which said fourth and third poles, respectively, are attracted to and positioned adjacent said first and second poles; and

said touch pin having a longitudinal axis transverse to said reference surface and including a follower end engageable with said cam means and a tip end distant from said follower end, said touch pin being movable on said cam means between a first position raised above said reference surface when said cam means is in said active position and a second position no higher than said reference surface when said cam means is in said inactive position.

6. Tactile display apparatus as set forth in claim 5

wherein said housing includes:

an integral roof positioned so as to overlie the cavity, said roof defining said reference surface and having therein the aperture for communication between the cavity and said reference surface;

wherein said reference surface is substantially planar; and

wherein said axis of rotation of said cam means and said longitudinal axis of said pin are both perpendicular to said reference surface.

7. Tactile display apparatus as set forth in claim 6

wherein said cam means is generally disk-shaped, has a planar base surface which is substantially parallel to said reference surface, and has an opposed contoured operative surface which ranges between an elevated region of maximum height above said base surface and a nominal region of minimum height above said base surface;

and

wherein said pin assumes said first position when said follower end is engaged with said elevated region and assumes said second position when said follower end is engaged with said nominal region.

8. Tactile display apparatus as set forth in claim 7 including:

means biasing said follower end into engagement with said operative surface.

9. Tactile display apparatus as set forth in claim 8

wherein said biasing means includes:

an annular shoulder on said pin intermediate said follower end and said tip end and lying in a plane substantially perpendicular to said longitudinal axis; and

a compression spring encircling said pin and extending between said annular shoulder and said cover.

10. Tactile display apparatus as set forth in claim 7

wherein said housing includes positioning means freely engageable with said cam means for maintaining the spacing between said cam means and said reference surface and for defining a center for rotation of said cam means.

11. Tactile display apparatus as set forth in claim 7

wherein said operative surface has a centrally disposed depression formed therein;

and

wherein said housing includes a positioning finger integral therewith and freely engageable with said depression for maintaining the spacing between said cam means and said reference surface and for defining a center of rotation for said cam means.

12. Tactile display apparatus as set forth in claim 5

wherein said cam means is generally disk-shaped, has a planar base surface which is substantially parallel to said reference surface, has a centrally disposed projection extending from said base surface, and has a contoured operative surface which ranges between an elevated region of maximum height above said base surface and a nominal region of minimum height above said base surface;

wherein said pin assumes said first position when said follower end is engaged with said elevated region and assumes said second position when said follower end is engaged with said nominal region; and

wherein said electromagnet lies generally in a plane parallel to that of said reference surface; and

including;

a planar bearing member mounted on said electromagnet and lying in a plane parallel to that of said reference surface, said bearing member having a surface facing said reference surface and having a centrally positioned dimple therein to freely receive said projection;

wherein said operative surface has a centrally disposed depression formed therein; and

wherein said housing includes a positioning finger integral therewith and freely engageable with said depression for maintaining the spacing between said cam means and said reference surface and for defining a center of rotation for said cam means.

13. Tactile display apparatus as set forth in claim 12 including:

means biasing said follower end into engagement with said operative surface.

14. Tactile display apparatus as set forth in claim 13

wherein said biasing means includes:

an annular shoulder on said pin intermediate said follower end and said tip end and lying in a plane substantially perpendicular to said longitudinal axis; and

a compression spring encircling said pin and extending between said annular shoulder and said cover.

15. Tactile display apparatus as set forth in claim 7 including:

means biasing said follower end into engagement with said operative surface.

16. Tactile display apparatus as set forth in claim 15

wherein said biasing means includes:

an annular shoulder on each of said pins intermediate said follower end and said tip end and lying in a plane substantially perpendicular to said longitudinal axis; and

a compression spring encircling each of said pins and extending between said annular shoulder and said cover.

17. Tactile display apparatus as set forth in claim 7

wherein said housing includes positioning means freely engageable with each of said cam means for maintaining the spacing between each of said cam means and said reference surface and for defining a center of rotation for each of said cam means.

18. Tactile display apparatus comprising:

a housing having a plurality of cavities therein and defining a reference surface and having a plurality of apertures therein for communication between each cavity and said reference surface;

an electromagnet fixed to said housing within each of the cavities, each said electromagnet being spaced from said reference surface and having first and second spaced poles of opposite, selectively reversible, polarity;

rotatable cam means proximate to each of said electromagnets, each of said cam means having an axis of rotation transverse to said reference surface and including an integral permanent magnet with third and fourth spaced poles of opposite polarity equidistant from said axis of rotation, each of said cam means being rotatable between an active position at which said third and fourth poles, respectively, are attracted to and positioned adjacent said first and second poles and an inactive position at which said fourth and third poles, respectively, are attracted to and positioned adjacent said first and second poles; and

a touch pin associated with each of said cam means and having a longitudinal axis transverse to said reference surface, each of said touch pins including a follower end engageable with said cam means and a tip end distant from said follower end, said touch pin being movable on said cam means between a first position raised above said reference surface when said cam means is in said active position and a second position no higher than said reference surface when said cam means is in said inactive position, the aperture being sized and positioned to freely receive said touch pin therethrough.

19. Tactile display apparatus as set forth in claim 18 wherein said housing includes:

an integral roof positioned so as to overlie all of the cavities therein, said roof defining said reference surface and having therein a plurality of apertures for communication between each of the cavities and said reference surface;

wherein said reference surface is substantially planar; and

wherein said axis of rotation of each of said cam means and said longitudinal axis of each of said touch pins are both perpendicular to said reference surface.

20. Tactile display apparatus as set forth in claim 19

wherein each of said cam means is generally disk-shaped, has a planar base surface which is substantially parallel to said reference surface, and has an opposed contoured operative surface which ranges between an elevated region of maximum height above said base surface and a nominal region of minimum height above said base surface;

and

wherein each of said pins assumes said first position when said follower end is engaged with said elevated region of its associated said cam means and assumes said second position when said follower end is engaged with said nominal region thereof.