Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.


  1. Advanced Patent Search
Publication numberUS1775755 A
Publication typeGrant
Publication dateSep 16, 1930
Filing dateNov 26, 1928
Priority dateNov 26, 1928
Publication numberUS 1775755 A, US 1775755A, US-A-1775755, US1775755 A, US1775755A
InventorsForman Paris R
Original AssigneeNat Pneumatic Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Treadle switch structure
US 1775755 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

Sept. 16, 1930. P. R. FORMAN TREADLE SWITCH STRUCTURE Filed Nov. ze, 1928 l//l z /zlr/ llf//lI/l/l/ R llm w v.


This invention relates to improvements in treadle structures.

The object of this invention is to .provide a treadle structure which is deformable.

Another object of this invention is to provide a treadle structure which is deformable and which on being deformed under a passengers Weight closes a circuit through contactors structurally disposed in said treadle structure to operate a door actuating engine.

Another object of this invention is to provide a deformable treadle structure which is so arranged that on Whichever portion of said treadle structure a passenger may step his weight will operate to close a door actuating circuit.

A still further object of this invention is to provide a treadle structure with a plurality of contactors located therein which are opel ted under a passengers weight to close door actuatingelectrical circuits.

Various other objects and advantages of the invention other than those hereinabove mentioned will be specifically pointed out or will be apparent hereinafter in the course of the below detailed description of the form of the invention shown in the accompanying drawings, as preferred ones of the various possible embodiments of the invention; it

eing understood, naturally, that such forms are merely illustrative of some of the many possible combinations and arrangements ofl parts well calculated to attain the objects of the invention and, hence, said detailed description of such form is not to be taken as at all defining or limiting the invention. That is to say, the scope of the invention contemplated is, of course, to be taken fromthe appended claims, interpreted as broadly as is consistent with the prior art.

- This invention resides substantially in the construction, combination, arrangement and relative location of parts, all as will be more fully indicated hereinafter.

Referring to the accompanying drawings embodying a disclosure of my invention:

Figure l is a top plan view of one embodiment of the treadle structure with a series of broken away portions at the lower right-hand corner of said figure;

Fig. 9. is a cross-sectional View taken 0n the line 2-2 of Fig. l;

Fig. 3 is a portion of an end view of the treadle structure shown in Fig. l at the lower right-hand corner where a portion has been broken away;

Fig. 4 is a perspectiveview of the stampedout body used in Fig. l.

Similar reference characters refer to similar parts throughout the several views of plate and when it moved under the weight of a passenger this contactor arm operated to close an electrical circuit.

The prior art has been replete with various patents and patent applications wherein inventers have conceived of operating door circuits mechanically or electrically but, invariably, in every case, the conception has been to utilize a solid treadle which, when it moved as a unit under the passengers feet, either actuated levers o-r itself closed a circuit with some other contact, or, in the alternative, opened pneumatic air lines to supply fluid pressure to a door operating engine. In this invention it is .proposed to eliminate the necessity for a movable treadle, that is to say,

it is proposed to have a treadle which is, as

a whole, fixed in relation to space, but which is deformable so that as a passenger steps onto said treadle thetreadle is compressed and there is closed therein the necessary electrical circuit contacts for door actuation. The advantages of this structure over the prior art are multitudinous, among them being the freedom of the treadle from wear and tear due to it being no longer necessary for the treadle to move as a body; the cheapness of manufacture; the ruggedness of construction; the ease of assembl the simplicity of repair; the longevity of t e finished product;

and elimination of movable treadle and hence danger of interruption of usefulness by accumulation of dust thereunder.

Referring specifically to the drawings in Fig. 1, at 1 is shown the general stampedout structure which goes to make up the treadle body. At 2 is shown a deformable and iiexible and brass sheet. At 3 is shown a rubber section interposed on top of said brass sheet. At 4 is shown a wire re-enforcing and electrical grounded screening covering said rubber interposed sheet and electrically groundedat 9. At 5 is shown an over-all rubber casing' placed on top of said wire mesh.

The general body structure 1 is obtained by taking a fairly non-deformable rubber plate of the desired thickness and stamping therein a series of parallelopipedal openings eX- tending entirely therethrough shown in Fig. 4 by the numeral 6. The completed rubber plate stamped with the series of parallelopipedal openings is then laid over a thin conduct-ing plate 7, preferably of copper, shown in Fig. 2 and covering it exactly. lInto each one of the stamped cavities is then dropped a hollow cylinder 8 of some conducting mate rial, such as brass. The outer diameter of this cylinder being of such a magnitude that it does not quite equal the thickness of the stamped rubber plate. On top of the rubber plate is then laid the flexible brass sheet 2 shown in Figs. 1, 2 and 3, and on top thereof is placed the flexible rubber sheeting 3, the reenforcing and grounding wire mesh 4, and thereafter the whole structure is covered by the flexible encasing rubber covering 5.

Looking at'Fig. 2 the operation of the im- -proved treadle structure will be observed as follows: When a passenger steps upon the flexible rubber casing 5 which encases the whole structure and which operates to insulate and water-proof the enclosed contact members it, will be deformed `under his weight. The effect of this deformation will be to move downwards at the particular portion of the treadle plate upon which he stands, the elements 5, 4, 3 and 2 and to cause the last of said elements 2 to contact with the hollow conducting cylinders 8 dropped into cavities 6 and which rest upon the copper conducting plate 7. It is thus apparent that the weight of a passenger coming upon the upper face of the treadle will operate to close an 'electrical circuit from the plate 7 to the lexible'brass sheet member 2.

Should a short-circuit occur vdu'e to the wearing through of the rubber elements at any portion thereof the potentials existing on the copper or brass plate will be grounded through the wire mesh 4 of to the ground rather than permeating the structure to the feet of a passenger stepping upon the treadle.

It is thus apparent vthat this structure fixed in relation to space and self deformable will operate upon a'passengers Weight to operate any necessary electrical door actuating systems.

inasmuch as many changes could be made A in the above constructions, and many apparently widely different embodiments of thelinvention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. v

It is also to be understood that the language contained in the following claims is intended to cover all the generic and specific features of the invention herein described, and all statements of the scope of the invention which,philologically speaking and as a matter of language, might be said to fall therebetween.

l do not wish to be understood as limiting myself to the exact structure 'shown or described, except as Set forth in the following claims when construed in the light of the prior art.

Having thus described my invention, I claim,

1. A deformable treadle having contained therein a plurality of contactors arranged to contact when said treadle is deformed under a passengers weight, and a reinforcing grounded conducting mesh work disposedl within said treadle over said contactors..

2. A deformable treadle having contained therein a series of pre-stamped cavities, a

series of conducting elements similarly located in each of said cavities, each reposing upon a conducting plate, a deformable conducting second plate, a wire re-enforcing grounded mesh separated from said second mentioned conducting plate by an interposed non-conducting sheet and a rubber casing, encasing the whole aforementioned structure.

3. A deformable treadle, comprising a lower rigid conducting plate and a deform able upper conducting plate, an insulating covering for said upper plate, a re-enforcing and grounded wire mesh disposed on said rubber covering, means interposed between said two conducting plates to provide acon- 'tinuous electrical circuit therebetween when said upper platevis deformed, together with a non-conducting deformable encasing body for said complete structure.

4. The combination of a non-deformable conducting plate, a stamped rubber framecontact element in eachv cavity, a ounded shield supported above and out o contact with said members, and a protecting covering encasing all of said parts.

5- 6. The combination of a non-deformable conducting late,adeformab1e treadle framework body aving contained therein a series of pre-stamped cavities, a deformable conducting plate, a deformable rubber insulating sheeting, a general rubber casing, and means allocated in said rubber framework to provide a continuous electrical circuit between the conducting plates when the deformable one is deformed.

7 `A treadle structure comprising two con,

ducting members in spaced relatlon, a deformable body interposed between said members having openings therethrough to form cavities, acylindrical errule havin a diameter somewhat Asmaller than the width of said deformable body disposed in each cavity,

' a grounded shield supported above and out of contact with said members and protecting the covering encasng all of the aforementioned parts.

In testimon whereof I have hereunto set my hand on this 20th day of November, A. D.,


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2615993 *Sep 26, 1950Oct 28, 1952Melvin A CarterElectronically operated advertising and sound reproducing apparatus
US2758836 *May 31, 1952Aug 14, 1956Frederick A PurdyDoor-operators
US3830991 *Jul 24, 1973Aug 20, 1974Essex International IncPressure sensitive mat switch construction
US4164634 *Jun 10, 1977Aug 14, 1979Telaris Telecommunications, Inc.Keyboard switch assembly with multiple isolated electrical engagement regions
US4554424 *May 25, 1984Nov 19, 1985Minnesota Mining And Manufacturing Co.Electrical switch
EP0109159A1 *Sep 29, 1983May 23, 1984Minnesota Mining And Manufacturing CompanyPressure sensitive switchmats
WO2009038478A2 *Sep 19, 2008Mar 26, 2009Thisit LimitedAn exercise platform
WO2009038478A3 *Sep 19, 2008May 28, 2009Thomas BangAn exercise platform
U.S. Classification200/86.00R, 235/99.00A, 49/264
International ClassificationH01H3/02, H01H3/14
Cooperative ClassificationH01H3/141
European ClassificationH01H3/14B