US1542931A

US1542931A - Automatic electric switch

Info

Publication number: US1542931A
Application number: US833767A
Authority: US
Inventors: Edward B Foote
Original assignee: Taylor Instrument Co
Current assignee: Taylor Instrument Co
Priority date: 1923-04-21
Filing date: 1923-04-21
Publication date: 1925-06-23
Anticipated expiration: 1942-06-23

Description

June 23, 1925. 1,542,931

E. B. FOOTE AUTOMATIC ELECTRIC SWITCH Filed April 21. 1923 Patented June 23, 1925.

UNITED STATES 1,542,931 PATENT OFFICE.

EDWARD B. FOOTE, OF ROCHESTER, NEW YORK, ASSIGNOB TO TAYLOR INSTRUMENT COMPANIES, OF ROCHESTER, NEW YORK, A CORPORATION OF NEW YORK.

AUTOMATIC ELECTRIC SWITCH.

Application filed April 21, 1923. Serial-No. 633,767.

To all whom it may concern:

Be it known that I, EDWARD B. Foo'rn, a citizen of the United States, residing at Rochester in the county of Monroe and State of ew York, have invented certain new and useful Improvements in Automatic Electric Switches; and I do hereby declare the following to be a full, clear, and exact descriptionof the same, reference being had to the accompanying drawings, forming part of this specification, and to the reference numerals marked thereon.

This invention relates to automatic electric switches of the variety adapted to be operated by fluid pressure, from a distant station if so desired, for opening or closing a switch controlling an electric circuit, the chief object ofthe invention being to provide a simple, practical and eflicient device of this character adapted to be selectively arranged for operation by fluid pressure to either open or close a controlled circuit.

In the drawings:

Figure 1 is a central sectional view through device of the class described embodying the present invention, and showing the same arranged for closing a circuit, an

Figure 2 is a similar view but showing the parts arranged for opening the controlled circuit.

Similar reference numerals throughout the several views indicate the same parts.

The invention is disclosed in the present instance, by way of illustration, as embodied in a form of construction and arrangement which has been found practical and efficient in actual use, comprising preferably a casing 5 formed with-a cylindrical bore 6 which serves as a pressure containing cylinder to which the operating fluid pressure, as for example compressed air, is admitted adjacent its opposite ends through ports 7 or 8 depending upon whether the device is to be used to close or open the controlled circuit, as hereinafter explained. Sliding within the cylinder in pressure tight relation with the walls thereof is a piston or plunger 9 preferably having a reduced end 10 adapted to engage the adjacent cylinder end as a stop for limiting the movement of the piston in that direction. The ends of the piston are furthermore preferably formed with peripheral depressions or seats 11 in which may be seated one end of a coiled spring 12 of a diameter adapted to fit loosely within the cylinder walls with the opposite end of the spring abutting the. corresponding cylinder "end. This spring may be selectively located in either end of the cylinder for urging the piston in opposite directions against fluid pressure applied through one of the ports 7 or 8, to operate switch means located at one end of the cylinder as more fully explained hereafter.

In the arrangement shown in Fi re 1 fluid pressure is admitted to the left hand end of the cylinder through a pipe 13, while port 8 communicatin with the opposite end of the cylinder is so stantially closed by a removable screw plug 14 having however a small vent aperture 15. It is apparent from this construction that spring 12 tends to maintain piston 9 at the left hand end of the cylinder as shown, and the admission of fluid pressure through pipe 13 moves the piston toward the right against spring 12 for operating the switch means in the right hand end of the cylinder hereafter described. In the arrangement of the above arts shown in Figure 2, however, spring 12 is placed in the left hand end of the cylinder and pipe 13 and plug 14 reversed in application to the cylinder ports so that the admission of pressure through pipe 13 tends to move the piston in the opposite direction against the pressure of the spring.

The switch parts comprise preferably a plug 16 provided with leads 17 for connection in a circuit to be controlled as indicated diagrammatically at 17 and having a threaded end 18' adapted to be screwed into the bore of a coupling sleeve 19 externally threaded as at 20 for engagement with the internally threaded end of the pressure cyllnder. The plug carries spaced insulated contacts 21 connected with the respective leads 17. The iston 9 at this end is centrally cored and tted with an insulated sleeve 22 in which is carried a post 23 having mounted on its end exteriorly of the piston a switch contact 24 adapted to bridge and connect contacts 21 when the piston is moved toward the right, the switch being shown in open position in Figure 1, and in closed position in Figure 2.

In operation the switch connections 17 are applied to the circuit to be controlled which may be of any variety. If the circuit is one which is normally open and it is desired to utilize the device for closing this circuit the parts are arranged as shown in Figure 1 with the pressure connection applied to the left hand port '2'. In this arrangement the application of fluid pressure from a suitable source of supply (not shown) serves to move the piston toward the right against the opposition of the spring and to close the switch contact. If, on the other hand, the circuit is a normally closed one which it is desired to open b 7 means of the device, then the connecting s eeve 19 is unscrewed with the plug 16 and the spring 12 and the piston removed, the spring being reinserted in the cylinder at its lefthand end and the piston sleeve and plug replaced as shown in Figure 2. In this arrangement the pressure is appiied through pipe 13 and the right hand port 8, the left hand port being closed by means of the plug 14. The admission of the fluid pressure then serves to move the piston toward the left, the confined air escaping through vent 15 of plug 14. The switch is thus opened against the force of the spring which tends to close it again when the pressure is removed.

As apparent from the above description and drawing, the device comprises but few parts of simple form which may be manufactured at a low cost and are of a durable nature capable of reliable operation over a long period of time. The parts may be quickly and easily disposed in either of the arrangements shown in Figures 1 and 2 for using the apparatus selectively to either open or close the circuit as may be desired in accordance with particular installations.

I claim as my invention:

1. In a fluid pressure operated switch for controlling an electric circuit, the combination of a cylinder, a piston therein, contacts adjacent one end of the cylinder, circuit control means adapted to be moved by the piston for opening and closing a circuit through said contacts, means for admitting fluid pressuretoeither end of the piston, and yieldable means adapted to be assembled at either end of the cylinder 50 as to maintain the switch either in open or closed position when the pressure of the fluid upon the piston is relieved.

2. In a fluid pressure operated switch, the combination of a pair of switch parts one of which is movable relatively to the other to open or close the switch, a pressure container, a pressure actuated member movable in said container and arranged to move said movable switch part, connections for applying fluid pressure to said member in either of two directions,.and motive means adapted to be selectively assembled at either end of said member to move it in either of said directions in opposition to said fluid pressure.

8. In a fluid pressure operated switch, the combination of switch parts movable relatively to each other to either open or close the switch, a pressure container, a pressure operated member movable in said container and provided with means for effecting said relative movement of the switch parts, connections for applying fluid pressure to said member in either of two directions for effecting corresponding movements thereof to open and close the switch, respectively, and motive means adapted to be selectively assembled in different positions for urging said member in either of said directions in oposition to said fluid pressure.

at. In a fluid pressure operated switch, the combination of switch parts having relative movements in either of two directions for opening and closing the switch respectively, a pressure container, a pressure operated member movable in either of two directions in said container and provided with means for effecting said relative movements of the switch parts, connections with a source of fluid pressure for applying the latter to said member selectively to effect either of said movements thereof, and spring means adapted to be selectively assembled in either of two different positions within said container for urging said member in either of said directions in opposition to said fluid pressure.

5. In a fluid pressure operated switch, the combination of switch parts having relative movement in either of two directions for opening and closing the switch respectively, a cylinder, a piston reciprocating in said cylinder and provided with means for effecting said relative movements of said switch parts, ports for selectively connecting said cylinder on opposite sides of said piston with a source of fluid pressure for effecting said movements of the piston and switch parts, and a coiled spring adapted to be assembled on either side of said piston for urging the latter in one of said directions in opposition to said fluid pressure.

6. In a fluid pressure operated switch, the combination of a cylinder, a piston reciprocably mounted therein, cooperating contact means disposed in one end of the cylinder adapted to be opened and closed by the reciprocation of the piston, ports for connecting said cylinder on opposite sides of said iston with a source of fluid pres sure, and a coiled spring adapted to be as sembled in one end of the cylinder to normally hold the contacts in closed position and also arranged to be assembled in the opposite end of the cylinder in a position to surround the contact means and to normally maintain it in open position.

EDIVARD B. FOOTE.