US2450329A - Pneumatic timing switch for electric circuits - Google Patents

Description

Sept. 28, 1948. E. c. DEANE PNEUMATIC TIMING SWITCH FOR ELECTRIC CIRCUITS 2 Sheets-Sheet 1 Filed April 30, 1945 ATTORNEY Sept. 28, 1948. E. c. DEANE PNEUMATIC TIMING SWITCH FOR ELECTRIC CI Filed April 50, 1945 RCUITS 2 Sheets-Sheet I2 INVENTOR. 6. D&d/7@

ATTORNEY Ear/ Patented Sept. 28, 1948 PNEUMATIC TIMING SWITCH FOR ELECTRIC CIRCUITS Earl C. Deane, North Kansas City, Mo. Application April 30, 1945, Serial No. 591,125

'7 Claims. 1

This invention relates to switches for electric circuits, and particularly make and break mechanism for circuits controlling lamps in locations Where automatic extinguishment is desired after the lapse of a predetermined length of time from the instant the circuit is made.

The primary aim of this invention is to provide a timing switch for electric circuits which employs a pneumatic principle and that may be positioned in any of a number of locations to control the circuit and cause the same to remain completed for a length of time previously selected by the operator.

Another important object of this invention is the provision of a pneumatic timing switch for electric circuits, having as an important part thereof, a bulb which is normally inflated. but that may be conveniently deflated when the circuit is made, after which the period of re-infiation determines the length of time that the circuit is made.

A yet further object of this invention is the provision of a switch of the aforementioned type having as a component part thereof, novel, manually settable means for controlling the speed of inflation of the bulb after the same has been deflated to a condition closing a number of contacts therein.

This invention has for a still further aim to provide a pneumatic timing switch assembly for electric circuits, said assembly having parts manipulable by the operator and disposed exteriorly of the bulb, for pre-setting the switch to remain closed during a. certain period of time and for permitting the operator to promptly open the circuit at any time, if such condition becomes desirable.

It is well-known that a tremendous amount of electrical current is wasted because electric lamps, appliances, and equipment are inadvertently left operably attached to the source of current, and many means have been heretofore devised to insure the breaking of circuits automatically, after the device receiving energy is no longer needed. The lack of universal application of such means as have been heretofore available and the complicated character thereof, has apparently precluded their general installation. The pneumatic timing switch embodying the invention about to be described, may be used in all of the various locations where electric switches have heretofore been provided. It may be used as a wall switch; as a switch adjacent to the socket containing an electric lamp; or as a pendulum type switch that depends from a fixture to within easy reach of the operator. The greatest application for switches of the character forming the subject matter of the invention, is in clothes closets, basements, attics, garages, warehouses, industrial plants, and, in fact, all places where illumination by electric lamps is needed for a limited length of time. For example, a light in a clothes closet is needed for but a minute or so, and a light in a basement may be needed for ten to fifteen minutes, depending upon conditions. The switch mechanism about to be described, may be set to cause the lamp to burn for several minutes, or for an hour or so, if desired.

A suflicient number of forms of the invention have been illustrated in the accompanying drawings, to reveal the versatility of the invention. In said drawings:

Fig. 1 is a side elevational view of a pneumatic timing switch for electrical circuits, made in accordance with the present invention and showing the essential elements thereof, supported within a conventional switch box of the wall type.

Fig. 2 is an enlarged vertical central sectional view through the switch parts.

Fig. 3 is an irregular sectional view taken on line III-III of Fig. 2, looking in the direction of the arrows.

Fig. 4 is a sectional view taken on line IV--IV of Fig. 2.

Fig. 5 is an enlarged detailed sectional view taken on line V-V of Fig. 2.

Fig. 6 is a fragmentary sectional view through the bulb portion of the switch taken on line VI-VI of Fig. 3.

Fig. 7 is an enlarged fragmentary sectional view taken on line VII-VII of Fig. 6.

Fig. 8 is a side elevational view of a switch embodying the mechanism illustrated in Fig. 2, but having a different commercial form than the switch illustrated in Fig. 1; and

Fig. 9 is a side elevational view of an electrical plug and socket fixture with a switch made as illustrated in Figs. 1 to 6 inclusive, housed therein.

The essential features of the switch mechanism are clearly detailed in Fig. 2, and an understanding of the parts illustrated therein, will readily indicate the manner in which the comparatively simple structure may be used as shown in Figs. 1. 8 and 9.

The exposed portion of the switch and that which is manipulated by the operator to complete a. circuit is bulb In having an air outlet port l2 and an air inlet port Id. In the instance shown, these ports are in the form of tubes,

3 the former being supplied with a flap valve I6 while the latter is joined to the hereinafter described manually settable means for controlling the speed of inflation of bulb Hl.

Bulb IB is normally inflated and is so molded that its body of insulating material has the inherent tendency of returning to the inflated condition shown clearly in Figs. 1 and 2.

Tube 14 forming intake for air, serves as a contact pin or point joined to a conductor l8, forming a part of the electric circuit which is to be opened and closed.

Contact pin is joined by conductor 22 and these members l4 and 20 are stationary and spaced apart to be bridged by the movable contact plate 24. Contact plate 24 is formed as more clearly illustrated in Fig. 3, and its one end is pivotally mounted as at 26 to the ends of legs 28 forming a part of a U-shaped member 30, secured to the base 32 of bulb 10.

Member is formed of resilient material to the end that the ends of legs 28 may spring toward and from each other as plate 24 swings about the axis of pivot pin 26.

A series of domes 34 pressed into leg 28 adjacent to one edge of plate 24 and in frictional engagement therewith, insures a stepby-step and snapping movement as plate 24 is actuated toward and from a place bridging points l4 and 20. No arcing will occur, therefore, because the inturned ears 35 of plate 24 quickly approach and leave the ends of members l4 and 20 as the switch is manipulated to and from the circuit making position.

A flexible cable 38 joins plate 24 and the outermost portion of bulb l0, and it is this cable 38 that exerts the necessary pull on plate 24 to withdraw it from the position against members l4 and 2D. The resiliency of the material from which plate 24 is made, is employed to insure a tight contact between cars 35 and the ends of members l4 and 20. One of the ears 35 has an opening 40 formed therethrough to register with the passageway in the tubular intake port I4, for the air enterin bulb 10 must pass through the tube 14 prior to the time when plate 24 is lifted from the end thereof.

As illustrated in Fig. 2, bulb H! has a very flexible section which extends from the outer wall of box 42 and a relatively stiff section that is disposed behind the front wall of box 42, for the purpose of rigidly supporting plate 24 and the parts extending through base 32.

Manually settable means for controlling the speed of inflation of bulb I0 is disposed near the bulb but exteriorly thereof. When the parts of the switch are mounted as illustrated in Figs. 1, 8 and 9, this settable means is relatively close to bulb Ill and within easy reach of the person operating the switch.

The said settable means comprises a tubular housing 44 for a shiftable core 46. This housing and core therefore, combine to present a valve through which the air entering bulb Ill, must pass at a rate of speed depending upon the size of passageway therethrough.

Housing 44 is joined to air intake tube M by a sleeve 48 constructed of insulating material to insure complete electrical isolation of the settable valve just mentioned, from conductors l8 and 22 forming the circuit being controlled.

A valve seat 50 interiorly of housing 44, cooperates with a shoulder 52 on core and as this core is turned about its longitudinal axis, by virtue of its threaded engagement with housing 44,

shoulder 52 is moved toward and from seat 50. An annular groove 54 communicates with longitudinal grooves 56 in core 46, to complete a passageway through the settable means which is governed by the movement of dial 58. This dial 58 is mounted on shaft 60 and has a pair of pins 62 inwardly directed to enter notches B4 in the end of core 46, The depth of these notches 64 is great enough to receive pins 62 throughout the limits of adjustment between dial 58 and core 45.

Indicia 66 on dial 58 are calibrated with respect to the size of the opening formed between seat 5|] and shoulder 52. A stop 68, rigid to housing 44, engages ear Hi when the dial 58 has moved through one complete revolution.

Shaft 60 is axially disposed through core 46 and is freely slidable in the bore 12 formed therethrough. A spring 14 yieldably maintains shaft 60 in a position where head 16 is against the inner end of core 45 to preclude the passage of air therethrough.

A lug l8 integral with housing 44 furnishes means for mounting the control mechanism adjacent to bulb in and, therefore, it is possible to place the above described parts in a housing such as the one illustrated in Fig. 8 or of the form shown in Fig. 9.

The manner of depressing bulb I0 is of no consequence, since it may be forced to a deflated condition by the thumb or fingers of the operator, or if the bulb is out of reach, any mechanical element may be brought into contact therewith to force the outer, relatively flexible section, inwardly to depress plate 24 and simultaneously evacuate air from within bulb Ill through either outlet port I2 or the passage through housing 44 that is of a size capable of allowing re-inflation of bulb Ill during the lapse of a predetermined time.

After the plate 24 has been moved to the circuit closing position bridging members [4 and 25, air will commence to enter bulb Ill through the space between shoulder 52 and seat 50. This space is in communication with annular groove 54 and longitudinal grooves 56, and the outer end of these longitudinal grooves is open to the atmosphere.

If it is desired to open the circuit before the lapse of the time necessary to re-inflate bulb I!) through the passage of air thereto via the ways just set forth, it is but necessary to move dial 5!! laterally in one direction (inwardly), to move head 16 from the end of core 46. Thus, bore 12 will be placed into direct communication with air intake port l4 through the medium of the extended part of housing 44 which is joined to I4 by coupling 48.

Dial 58 may be turned without efiecting the function of the quickly releasable portions of the settable means for opening the circuit at any time.

When the switch is to be manipulated, dial 58 is turned with respect to stop 68 that serves as an indicator, and when the indicia representing the amount of time to elapse is opposite the pointer or stop 68, the switch is ready for further manipulation. Bulb I0 is then deflated by forcing the outermost section thereof inwardly against plate 24 to bridge points l4 and 2B. As the bulb draws air into the hollow interior thereof, air will enter through the valve above described, at a rate of speed commensurate with the setting and the bulb will re-inflate to pull plate 24 away from members 14 and 20 when the period of time indicated by the numerals on dial 58, has elapsed.

Switches constructed in accordance with this invention and embodying the principles made clear during the foregoing specifications, may have physical characteristics different from those revealed in the form of the invention chosen for illustration, and, therefore, it is desired to be limited only by the scope of the appended claims.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

1. An electric switch of the character described, comprising a normally inflated, compressible bulb of non-conducting material having an air outlet port and an air inlet port; contacts within the bulb, movable to and from the circuit closing position as the bulb is deflated and inflated respectively; and manually settable means for controlling the entrance of air into the bulb through said inlet port after the bulb has been deflated to a condition closing the contacts therein, said settable means having a slidable valve adapted for quick manual release permitting inflation of the bulb through said inlet port in a minimum amount of time and without the influence of the speed controlling means.

2. An electric switch of the character described, comprising a normally inflated, compressible bulb of non-conducting material having an air outlet port and an air inlet port; contacts within the bulb, movable to and from the circuit closing position as the bulb is deflated and inflated respectively; and manually settable means for controlling the speed of inflation of the bulb after the same has been deflated to a condition closing the contacts therein, said means including a slidable valve for selectively rendering the manually set table means inoperative and causing the bulb to be inflated in a, minimum amount of time, said valve being operable independently from that portion of said means for controlling the speed of inflation of the bulb.

3. An electric switch of the character described, comprising a normally inflated, compressible bulb of non-conducting material having an air outlet port and an air inlet port; contacts within the bulb, movable to and from the circuit closing position as the bulb is deflated and inflated respectively; manually settable means for controlling the speed of inflation of the bulb after the same has been deflated to a condition closing the contacts therein, said manually settable means having a tube in connection with the air intake port of the bulb, a valve seat in the tube and a valve member shiftable toward and from the valve seat to alter the size of the passage through the tube, whereby inflation of the bulb is caused to occur in a. predetermined amount of time; and a second valve within said valve member slidable to and from a. position permitting quick inflation of the bulb after the same has been deflated.

4. An electric switch of the character described comprising a, normally inflated, compressible bulb of non-conducting material having an air outlet port an an air inlet port; contacts within the bulb, movable to and from the circuit closing position as the bulb is deflated and inflated respectively; and manually settable means for controlling the speed of inflation of the bulb after the same has been deflated to a condition closing the contacts therein, said manually settable means having a tube in connection with the air intake port of the bulb, a valve seat in the tube and a valve member shiftable toward and from the valve seat to alter the size of the passage through the tube, whereby inflation of the bulb is caused to occur in a predetermined amount of time, said valve member being provided with a dial having indicia thereon for revealing to the operator the length of time required for the bulb to inflate to a degree where the contacts therein are shifted to open the circuit, said dial being rotatably movable and laterally reciprocable, the valve member member being adapted to fully open and allow inflation of the bulb in a minimum amount of time when the dial is shifted laterally through its path of travel in one direction.

5. An electric switch of the character described. comprising a normally inflated, compressible bulb of non-conducting material having an air outlet port and an air inlet port; contacts within the bulb, movable to and from the circuit closing position as the bulb is deflated and inflated respectively; and manually settable means for controlling the speed of inflation of the bulb after the same has been deflated to a condition closing the contacts therein, said contacts in the bulb including a pair of spaced apart stationary pins, a pivotally mounted plate bridging the pins when the contacts are closed, and detents for yieldably holding the plate against accidental movement, the plate having a flexible connection to the bulb to draw the plate from the bridging position as the bulb is inflated.

6. An electric switch of the character described, comprising a normally inflated, compressible bulb of non-conducting material having an air outlet port and an air inlet port; contacts within the bulb, movable to and from the circuit closing position as the bulb is deflated and inflated respectively; and manually settable means for controlling the speed of inflation of the bulb after the same has been deflated to a condition closing the contacts therein, said contacts in the bulb including a pair of spaced apart stationary pins, a pivotally mounted plate bridging the pins when the contacts are closed, and detents for yieldably holding the plate against accidental movement, said detents being adapted to impart quick stepby-step action to the plate as it swings about the pivotal connection.

7. In an electric switch having an inflatable body and means controlled by the deflation and inflation of said body for respectively making and breaking an electric circuit; an air inlet conduit communicating with said body; a rotatable valve and a slidable valve, each moveable to and from a position closing one end of said conduit; and manually manipulable means common to said valves for separately actuating the same.

EARL C. DEANE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,398,183 Jones Apr. 9, 1946 FOREIGN PATENTS- Number Country Date 20,992 Great Britain 1890 526,409 Germany July 15, 1932 593,677 Germany Mar. 3, 1934

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