US3667787A

US3667787A - Key top mount

Info

Publication number: US3667787A
Application number: US97675A
Authority: US
Inventors: Norman F Semour
Original assignee: Key Tronic Corp
Current assignee: Key Tronic Corp
Priority date: 1970-12-14
Filing date: 1970-12-14
Publication date: 1972-06-06
Anticipated expiration: 1989-06-06

Abstract

A KEY TOP MOUNT FOR COMPUTER TERMINALS OR OTHER KEYBOARD INSTALLATIONS. THE KEY TOP RECESS AND SUPPORTING PLUNGER POST END ARE COMPLEMENTARY TO ONE ANOTHER. INCLINED SURFACES ARE PROVIDED IN SUCH FASHION AS TO PERMIT ALTERNATE POSITIONING OF THE KEY TOP ON THE PLUNGER. BY TURNING ON ELEMENT 180* RELATIVE TO THE OTHER, THE KEY TOP CAN BE POSITIONED PERPENDICULAR TO THE POST OR CAN BE ANGULARLY INCLINED.

Description

June

Filed FIg.I

Dec. 14, 1970 N. F. SEMOUR KEY TOP MOUNT 3 Sheets-Sheet l INVENTOR. Mar-m an 7 5 eymour Jun 6, 7 N. F. SEMOUR 3,667,787

. Pi l e d D as. 14, 1970 3 Sheets-Sheet 5 United States Patent 3,667,787 KEY TOP MOUNT Norman F. Senrour, Coeur dArlene, Idaho, assignor to Key Tronic Corp., Spokane, Wash. Filed Dec. 14, 1970, Ser. No. 97,675 Int. Cl. F16d 1/06 US. Cl. 287-53 H 4 Claims ABSTRACT OF THE DISCLOSURE A key top mount for computer terminals or other keyboard installations. The key top recess and suppOrting plunger post end are complementary to one another. Inclined surfaces are provided in such fashion as to permit alternate positioning of the key top on the plunger. By turning one element 180 relative to the other, the key top can be positioned perpendicular to the post or can be angularly inclined.

BACKGROUND OF THE INVENTION The present device relates to manual keyboards, such as used in computer terminals, office machines, and other manually controlled electronic installations. It is concerned with the physical mounting of the key top to a post or plunger. The post can be either reciprocal, as when used to control a switch that is actuated by longitudinal movement of the plunger, or can be stationary, as when used to control devices operated by proximity of the users finger to the key top.

For various reasons, keyboard consumers prefer the mounting of key tops in a plane perpendicular to the plunger in some installation and in a slightly inclined plane in others. Manufacturers of key tops must normally be able to supply both alternatives. This has been accomplished previously by using separate plungers or separate key tops, and by inserting inclined bases under the normal- 1y upright switch units in a keyboard. The use of separate key tops or plungers requires duplication of inventory and manufacturing effort. The use of inclined bases under the switches or electronic devices adds to their normal height and requires modification of the external dimensions of the keyboard. The use of inclined bases is also detrimental when utilized with electronic devices designed for upright positions.

According to the present device, a single plunger and single key top can be used for positioning in either the perpendicular or inclined orientation. The choice of orientation can be readily modified by intermediate manufacturers or even by the ultimate user. The key top can be frictionally or permanently mounted on the plunger as desired. The modification of the orientation of the key top on the plunger does not modify its nominal working height nor add to the height or bulk of the entire switch apparatus. Repositioning of the key top further does not crowd the key tops adjacent to one another or substantially vary the spacing between them.

SUMMARY OF THE INVENTION The invention disclosed herein essentially relates to an apparatus for supporting a member on a post. The post, which has a longitudinal axis, includes inclined side surface areas formed at the desired angle of inclination of the key top relative to a plane perpendicular to the post axis. The key top or other member mounted to the post includes an open recess that receives the post and has interior surfaces engaging the exterior sides of the post to fix its position relative to the post. This recess also includes inclined surfaces complementary to those on the post in such manner that alternate positions of the memher are effected by turning the post or member about its axis relative to the other.

One object of the invention is to elimintae the necessity of manufacturing and stocking duplicate key tops or posts in order to supply users with key top combinations both perpendicular and inclined relative to a supporting post.

Another object of the invention is to provide a key top and post which can be readily changed from one key top orientation to another.

Another object of the invention is to provide an alternate key top mount which does not substantially vary the height or lateral spacings of the key tops when in either of their respective alternate orientations.

These and further objects of the invention will be evident from the following disclosure, taken together with the accompanying drawings, which illustrate a preferred form of the invention. It is to be understood that this form of the invention is presented by way of example only, and that modifications might be made within the bounds of the description.

DESCRIPTION OF THE DRAWINGS FGI. 1 is a side elevation view of a plunger constructed according to the disclosure;

FIG. 2 is an end elevation view of the plunger as seen from the right in FIG. 1;

FIG. 3 is a longitudinal cross-sectional view taken along line 33 in FIG. 1;

FIG. 4 is a top view of the plunger shown in FIG. 1; FIG. 5 is a top view of a key top according to the disclosure;

FIG. 6 is a bottom view of the key top in FIG. 5; IlgIG. 7 is a sectional view taken along line 77 in F 5;

FIG. 8 is a sectional view taken along line 8-8 in FIG. 5;

FIG. 9 is an assembly view of the post and key top, with the key top being illustrated in section; and

FIG. 10 is a view similar to FIG. 9, showing the alternate orientation of the key top.

DESCRIPTION OF THE PREFERRED EMBODIMENT The drawings illustrate a typical plunger and key top as used in the practice of the present invention. The plunger 10 and key top 20 are each molded or otherwise fabricated from any suitable material, such as injection molded plastic resins. The base 11 of plunger 10 is circular in cross-section and hollow. It includes outer guiding ribs 12 which prevent its rotation when mounted in a switch assembly (not shown). Plunger 10 may be used as the actuator for any type of electrical switch or other manually operated electrical device. At present, most keyboard installations utilize a plurality of axially movable plungers 10 to activate push-button reed switches. EX- amples of such switches are illustrated in the US. patent to De Falco, No. 3,283,274. It is not believed that further elaboration is required as to the switches or other devices that might be operated by reciprocation of plunger 10.

For purposes of the present discussion, reference shall be made to the key top 20 and to the plunger or post 10. It is to be understood that the term key top applies to the upper element on the assembly. It is this element which is manually touched or pushed to activate the electrical or electronic device controlled thereby. The key top 20 is also known in the industry as a key button or button. Many such elements are also known as lenses. They can be molded in one piece or in multiple layers to facilitate imprinting by engraving. They also can be hollow, transparent, back-lighted, etc. The plunger 10 isthe activating element for the apparatus controlled thereby. It is not necessarily movable. It might be immobile and used to activate electrical devices operated by the proximity of ice an operators finger, so as to be activated by simply touching the upper surface of the key top. The plunger is also known in the industry as a key.

The general purpose of the present physical structure is to provide a plunger 10 and key top 20 wherein the key top can be axially aligned on the plunger 10 as shown in FIG. 9 or alternately inclined across the end of plunger 10 as shown in FIG. 10. In the present arrangement, this alternate positioning of key top 20 is achieved by relative rotational movement between key top 20 and plunger 10 to turn one 180 relative to the other. As can be seen by the relative positions in FIGS. 9 and 10, the lateral spacing between adjacent key tops 20 is not substantially varied between the two positions. The center of key top 20 is also at substantially the same elevation in both positions.

To achieve the results illustrated in FIGS. 9 and 10, plunger 10 is constructed as shown in FIGS. I4 and the key top is constructed as illustrated in FIGS. 58.

Directing attention first to the construction of plunger 10, it includes an elongated post 13 closed at its outer end 14. The post 13 and base 11 are integrally molded and are hollow so as to provide mounting space for the switch assembly activated thereby. Post 13 is illustrated as being square in cross-sectional configuration along planes perpendicular to its central longitudinal axis. It might alternately be rectangular, being symmetrical about a transverse axis indicated in FIG. 4 by the line XX.

The plane side surfaces intersected by plane XX are indicated at 15. The post 13 is completed by oppositely facing side surfaces desigated by the

numerals

16, 17. The sides 15 are parallel to one another, as are

sides

16 and 17.

At its top or outer end, the plunger post 13 is relieved adjacent to the corners to one side of the plane XX. This relief is provided along inclined surfaces 18 which subtend an angle 21 relative to the intersecting side surface 15. The inclined surfaces 18 extend outwardly to the end of post 13 and merge along post 13 with the side surface 16. Their width is a relatively small portion of the total width across the side 16 (FIG. 2).

The end surface 14 of post 13 is also angularly relieved across its entire width. The inclined area 22 of the end surface 14 subtends an angle with respect to the remainder of end surface 14 equal to the angle 21.

The illustrated key top is substantially square, having curved exterior and interior surfaces for asthetic and functional purposes to facilitate manual engagement. It includes an upper indented area 23 which is contacted by the opertors finger to activate the devices controlled thereby. Beneath the area 23 is a socket or recess adapted to fit upon the outer end of plunger post 13 in a secure fashion. The recess, generally designated at 24, is de-- fined by four corner guides located to opposite sides of a central transverse longitudinal plane YY indicated in FIG. 6. A pair of corner guides 25 to one side of plane YY are mirror images of one another. The second pair of corner guides 26 positioned to the opposite side of plane YY are also mirror images of one another. Each

guide

25, 26 includes longitudinal parallel surfaces 27 complementary to the side surfaces 15 of plunger post 13.

The corner guides 25 include inclined shoulders 28 which project inwardly along the surfaces 27. The plane of the inner surfaces of shoulders 28 converges along an angle designated at 29, toward plane YY in an inward direction through the recess 24. Angle 28 is equal in magnitude to angle 21. The guides 25 further include surfaces 30 which are perpendicular to surfaces 27 and which project toward one another beyond the width of the shoulders 28.

The corner guides 26 include inner surfaces 31 which are perpendicular to their respective surfaces 27. The spacing between surfaces 31 and surfaces 30 is complementary to the exterior spacing between the guide surfaces 16, 17 of the plunger post 13. The width of surfaces 31 corresponds to the width of the inclined shoul- 4 ders 28 and their positions relative to surfaces 27 correspond to the relative position of the shoulders 28.

The inner end of recess 24 is defined by a convex surface 32 of constant radius, designed to contact the outer end of the plunger post substantially at its center.

As can be seen in FIG. 9, the plunger 10 is capable of being received within key top 20 in such an orientation that the prospective planes X-X and YY coincide, with the key top20 substantially perpendicular to the axis of plunger 10. This is accomplished by axially orienting the two elements in such positions that the inclined surfaces 18 on plunger post 13 engage the inclined shoulders 28. At the same time, the plunger side surfaces 15 are engaged by the surfaces 27 of recess 24 and the plunger side surfaces 16, 17 are engaged by

surfaces

30, 31 respectively. The perpendicularly end portion 14 at the outer end of post 13 is engaged at the center of the convex surface 32 so as to axially position key top 20 on plunger 10. Key top 20 is thereby fixed relative to plunger 10 and is capable of transmitting axial forces to reciprocate plunger 10 as necessary.

When it is desired that the key top 20 be angularly inclined with respect to the plunger post 13, one must be turned relative to the other. When key top 20 is then mounted upon the outer end of plunger 10, the plunger post side surface 17 will engage the inclined shoulders 28 and the inclined surfaces 18 at the outer end of post 13 will engage the surfaces 31 of the corner guides 26. The planar central portions of the side surface 16 on post 13 will project outwardly between the surfaces 31, since the width of the respective surfaces 31 is coincident with the width of the inclined shoulders 28, as described above.

The central portion of con-vex surface 32 at the base of recess 24 will contact the inclined end surface 22 on post 13. Because of the inclination of surface 22, the effective height of key top 20 is not substantially varied in the inclined position from that in its perpendicular position. Also, because the inclined guide surfaces extend along substantially the entire height of the key top, it is pivoted about a point coincident with its lower edge or base and indicated by the intersection of planes XX and Y--Y in FIG. 10. The angle 33 of inclination subtended by key top 20 is identical to the previously described

angles

21 and 29.

Various modifications might be made in the exact structure shown. It is to be understood that the shapes of the key tops and plungers are not to be limited to the precise structure shown. The key tops 20 can be elongated and might be supported by one or more plungers 10, as Well as parallel sliding guides. The plungers 10 can be either stationary or reciprocable, and can have enlarged bases or other attachments as required. It also is not necessary that key top 20 seat against the outer end of plunger post 13. It might be located by interior or exterior shoulders on either the key top recess 24 or plunger post 13, or both.

The disclosed arrangement makes it exceptionally easy to provide alternate orientation of a key top relative to the post by simply reversing the position of either one about its central axis. This can be accomplished by turning the key tops where no printed material is displayed on their outer surfaces. It also can be accomplished by turning the entire switch assembly or only the plunger. In some instances, an entire group of switch assemblies can be turned 180 as a unit and the individual key tops 20 then replaced on their outer ends.

The principal advantage of the above arrangement is the elimination of the necessity of manufacturing and stocking two dilferent sets of key tops to meet the demands of perpendicular and inclined mounting. Furthermore, inclination of the key top is achieved without materially adding to the height of the plunger or switch assembly, as has been the case with prior alternative structural arrangements. Furthermore, the key tops are not moved laterally by inclination, and the rows of key tops do not crowd one another.

Because the present structural arrangement is capable of a wide range of usage, the above-described physical relationship is to be taken only by Way of example and is not to limit the scope of the invention disclosed herein.

Having thus described my invention, I claim:

1. In an apparatus for supporting a member on a post:

a post having a longitudinal axis, and a rectangular cross-sectional configuration perpendicular to said axis, said post including first and second side surfaces along opposite sides thereof;

a member having an open recess centered along a longitudinal axis adapted to receive one end of said post and including interior surfaces for respectively engaging the exterior sides of the post so as to fix the position of the member relative to the post;

and means formed along the interior surfaces of the recess and along the exterior sides of the post for alternately positioning the member on the post with the respective axes thereof coincident with one another or with the respective axes thereof inclined angularly with respect to one another;

the alternate positions of the member being effected by turning the post or the member about its axis 180 relative to the other.

2. In an apparatus for supporting a member on a post:

a post having a rectangular cross-sectional configuration including spaced parallel exterior side surfaces at opposite sides of a central transverse plane;

a member having a recess formed therein adapted to receive one end of said post;

said post including an inclined longitudinal surface along a portion of one of said side surfaces extending to said one end thereof in a plane angularly offset from its central transverse plane;

the recess of said member having a first interior Wall surface therein at one side for selectively engaging a portion of the one side surface and including an angularly inclined longitudinal surface complementary to the inclined surface of the post;

said recess comprising a second interior wall surface therein spaced from its first interior wall surface and parallel to said portion thereof, said second Wall surface being co-extensive with the inclined surface of the post so as to be engageable only by said inclined surface along said one post side surface.

3. In an apparatus for supporting a member on a post:

said post having the respective longitudinal corners thereof relieved at one side of the post along a cmmon plane inclined relative to said one side surface to present recessed bearing surfaces extending to said one end of the post;

the recess of said member incluring first and second bearing walls adapted to respectively engage the side surfaces of the post;

said first and second bearing Walls each including parallel surface portions for engaging the parallel exterior side surfaces of the post;

said first bearing wall further including inwardly projecting inclined longitudinal surfaces complementary to the recessed bearing surfaces along said one side surface of said post;

the parallel surface portions of said second bearing wall being co-extensive with the recessed bearing surfaces along said one side surface of said post across said second bearing wall area.

4. A post having a rectangular exterior cross-sectional configuration symmetrical about a central transverse plane;

a member mounted on one end of said post having a recess formed therein with an interior cross-sectional configuration that is symmetrical about a central transverse plane and complementary to the cross-sectional configuration of said post;

the recess of said socket having corner bearing surfaces for respective engagement by the corners of the post;

the corner bearing surfaces of the recess to one side of the central transverse plane of said member having longitudinally inclined surfaces extending therealong and converging inwardly of the socket toward said plane;

the corners of the post adjacent said one end and to one side of the central transverse plane of said post having longitudinally inclined surfaces extending thereon and converging outwardly of the post end toward said plane;

the angle of inclination, width and placement of the respective inclined surfaces of said member and post being complementary.

References Cited UNITED STATES PATENTS 2,189,845 2/1940 Terrill 287-53 H 2,877,490 3/1959 Greninger 16-121 3,047,700 7/1962 Bailey 16-121 X 3,193,312 7/1965 Ehner 287-53 H FOREIGN PATENTS 1,358,445 3/ 1964 France 287-53 H ANDREW V. KUNDRAT, Primary Examiner US. Cl. X.R.