US1388541A - Circuit-controlling apparatus - Google Patents

Circuit-controlling apparatus Download PDF

Info

Publication number
US1388541A
US1388541A US276849A US27684919A US1388541A US 1388541 A US1388541 A US 1388541A US 276849 A US276849 A US 276849A US 27684919 A US27684919 A US 27684919A US 1388541 A US1388541 A US 1388541A
Authority
US
United States
Prior art keywords
circuit
switch
contact
magnet
rotary
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US276849A
Inventor
Homer C Woodbury
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to US276849A priority Critical patent/US1388541A/en
Application granted granted Critical
Publication of US1388541A publication Critical patent/US1388541A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • GPHYSICS
    • G05CONTROLLING; REGULATING
    • G05DSYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D23/00Control of temperature
    • G05D23/19Control of temperature characterised by the use of electric means
    • G05D23/275Control of temperature characterised by the use of electric means with sensing element expanding, contracting, or fusing in response to changes of temperature
    • G05D23/27535Details of the sensing element
    • G05D23/2754Details of the sensing element using bimetallic element

Definitions

  • This invention has for its object improved mechanism for automatically controlling the circuit of an electric motor, or other trans: lating device, to perform certain work in accordance with a variable demand for such work. It is designed primarily for use in connection with a rotary hydrocarbon burner in which organization a motor is used to operate the burner and the invention hereinafter described comprises convenient arrangement of circuit cont-rolling devices whereby the burner is put into or out of operation in accordance with temperature changes influenced by the burner. Its use, however, is not limited to this particular art, but it is capable of use 'in many other organizations as will be apparent to one skilled in the art. I
  • a thermostatic device capable of movementin response to changes of temperature
  • Figure 1 is a diagrammatic representation of the invention; showing its relation to the circuits which it controls and by which it is controlled
  • Fig. 2 is a plan view of the electro-magnetic circuit controlling device
  • Figs. 3 and -l are respectively side and end elevations of the same: i i
  • Fig. 5 is a detail view of the pawl and ratchet switch actuating mechanism:
  • Fig. 6 is a detail view of the rotary, cylindrical switch for the motor circuit, the contact' fingers of which are shown in dotted lines;
  • Fig. 7 is a view of the ratchet disk, carry-.
  • FIGs. 8 and 9 are detail views showing the component parts of said last named switch
  • - Fig. 10 is an assembled View of the two. sw1tches,-mounted on their common supporting shaft, and
  • Fig. 11 is a sectional View on the line 1111 of Fig. 7.
  • M is a motor, or other translating device, the circuit of which it is desired to control. It is assumed that current for operating the mo tor is supplied .from any suitable supply mains which form no part of the present invention.
  • the entire circuit controlling mechanism of this invention is conveniently mounted upon a panel or supporting plate P, withbinding-posts or terminals for all of the circuit connections, arranged so as to be readily accessible.
  • the rotating element-of this switch comprises a cylinder, the peripheral surface of which is divided into diametrically opposite insulating and conducting areas, the latter being electrically connected.
  • Resilient contact fingers or brushes (Z and d engage the periphery of the movable elements of the switch at diametrically opposite points and are either separated by insulation or electrically connected, depending upon the position occupied by said movable element.
  • the transition points on the switch are arranged (see Fig. 6) so as to effect a quick making or breaking of the circuit. This is accomplished by providing an abrupt step on the periphery between areas of contact and insulation.
  • the switch S is mounted upon and secured to a shaft A, but electrically insulated therefrom, in order to effectually prevent the relatively heavy currents of the motor circuit from coming into contact with anv other part of this circuit controlllng mechanism.
  • the shaft A is mounted for r0- tation in bearings a and b rigidly supported upon the base plate or panel l
  • the outer bearing (a is in an overhanging arm of a supporting element L, the extent of the 0ver-- hang being suiiicient to give clearance to all switch and actuating mechanism mounted upon the shaft.
  • the shaft A also carries a ratchet disk D, by means of which rotary motion may be imparted to the said shaft.
  • An electro-magnet E is mounted upon the base-plate P, being held in position by bolt connection with an upright arm f oi a metallic supporting frame U.
  • An armature 18 is pivotally supported at one end of the magnet upon a spring tongue G, which normally acts to hold the armature away from the pole-face of the magnet.
  • A. vertical extension or lever H is secured to the armature, and is provided at its upper end with a bale-like pawl K to engage and operate the ratchet disk D.
  • the pawl is held in engagement with the ratchet by pressure oi: one end K of the pawl loop, against a backwardly bent portion in of the armature extension H.
  • the usual adjustable stop in the nature of a screw N with lock-nut is provided to limit the backward movement of the armature.
  • the electro-magnet when energized will produce a vibratory movement of its armature l and extension H, which movement will transmit rotary motion to the shaft A through the pawl and ratchet mechanism in a manner readily apparent.
  • This motion ot the shaft A resulting from energization of the magnet E would continue as long as the magnet circuit remains closed, with resultant alternate opening and closing'oi the circuit of the motor M, were no provision made for limiting the operation to that desired, namely, opening or closing the motor circuit.
  • a second rotary switch is employed to secondarily control the circuit of the magnet in the manner hereinafter described.
  • This switch is of disk-like form and mounted upon the shaft A upon whichis also mounted the ratchet disk D and rotates in unison therewith. It consists of a circular contact plate or disk R, which may be cut or stamped into the configuration shown in Fig. 9, having the bent up portions 7 and 1- and a segmental insulating disk R secured thereto. Spring-pressed fingers e and e cooperate with the movable element of the switch. These fingers are supported from and in electrical contact with the bindingposts 3 and 4:.
  • a contact relative PI'OPOl't'lOIlS of exposed insulation and contact areas of the switch are such that by rotation of the switch through an angle of approximately the relation of the contact fingers or brushes 6, 0 will be reversed, that is, the brush which previously rested on a contact surface, will after the indicated movement, rest on an insulating 85 area, and the brush which rested on insulation, will engage a contact surface.
  • This amount of angular displacement of the switch Q insures a movement of the switch S sutiicient to cause it to either make or break the circuit which it controls.
  • AHSO- ciated with brushes 6 and e is a thermostatic or equivalent element T having a pointer or tongue i which moves in response to changes in temperature to engage one or the other of the fixed contact points r2 or 29".
  • Each of these contact points is electrically connected to one of the brushes 6, c; t being connected to c and t with e.
  • the fixed end at the thermostatic element is connected 10c permanently with one terminal of a primary or secondary battery B of suilicient ca pacity to properly energize the electro-magnet 1
  • the opposite terminal of the battery B is electrically connected with one end of the winding of the magnet ll, the other end of said winding being in electrical connection with the limiting stop N of the magnet armature in the usual manner.
  • a shunt connection V is provided for the magnet l), which is of advantage in reducing the spa rking between the points of making and breaking the magnet circuit. due to the vibrating of its armature.
  • Fig. 1 the condition of the several circuits is as follows:
  • the circuit of the motor or other translating device M is interrupted at the switch S.
  • the thermostat T makes contact at t which connects with the brush a. Since the latter rests on an insulating arca R of the disk switch the circuit of the electro-magnet l] is also interrupted and the controlling device remains inactive.
  • the thermostat T moving automatically in response to such change, may swing its pointer 15 into engagement with the contact 16 Current from the battery B can then flow through the thermostat to the all?) convinced-i thence back to the opposite pole of the battery.
  • circuit controlling apparatus for regulating the supply or electric energy to a motor-operated hydrocarbon burner, the combination of a rotary switch in the circuit of said motor, an electro-magnetic relay for operating said switch to eilcct the making or breaking of the motor circuit, a thermostat for controlling the relay circuit, and a second rotary switch also operated by the relay tobreak the relay circuit, after the operation of making or breaking the motor circuit shall have been completed, substantially as described.
  • a circuit controlling device comprising a plurality of rotary contact switches mounted upon a common shaft andadapted to control as many independent electric circuits, a pawl and ratchet actuating mechasm for g'said shaft, an electromagnet for actuating said pawl and ratchet dezvice; the circuit of said magnet being secondarily controlled by one of the rotary contact switches, and circuit controlling means responsive to temperature changes for primarily closing the magnet circuit to eilect the operation of all the rotary switches in such sequence that the rotary switch of the magnet circuit will break this circuit only after such movement of the other switches as is necessary to effect a change in the circuit which they control, substantially as described.
  • a circuit controlling device comprising a rotary contact switch for controlling the making or breaking of a motor circuit, a shaft upon which said switch is carried, a ratchet disk also mounted upon said shaft, a spring-pressed pawl adapted to engage said disk and transmit motion thereto, an electromagnet having a vibratory armature for operating said pawl, a second rotary contact switch mounted upon said shaftand adapted to turn with the ratchet disk; the areas of contact and insulation on said last named switch being substantially equal, two contact areas of like extent being separated by insulation areas of similar extent, two resilient contact fingers engaging the surface of said switch at points separated by a distanc corresponding to the length of one contact area, and automatic temperature controlled means for closing the magnet circuit through one of the contact lingers and conducting element of the switch associated therewith, to operate the circuit controlling device to the extent of producing an angular displacement of the shaft carrying the rotary switches equal to an angle of approximately 90, by which movement of the shaft a change is made by the rotary switch in the motor circuit, followed by a
  • a thermostatically controlled electromagnetic circuit controlling device including a motor circuit and rotary switch capable of operation to make or break said circuit, a shaft mounted in suitable bearings and carrying the movable element of said switch but electrically insulated therefrom, a second rotary switch also carried by the shaft and so positioned thereon that the conducting areas of the two switches are relatively displaced by an angle of approximately 90, tw o resilient contact fingers engaging the second rotary switch at separated circumferential points, a lead from each contact finger adapted to be connected at one terminal of athermostat, the movable element of which n is designed to make contact with one or the other of these terminals, an electro-magnet the circuit of which is controlled by said second rotary switch, and pawl and ratchet mechanism operated by the magnet to pro- 13o symbolize a measured rotation of the shaft suflithe circuit including the last-named contact 10 cient to operate the rotary switches to effect by the thermostat, substantially as described.

Description

H. C. WOUDBURY.
cmcun CGNTROLLING APPARATUS. APPLICATION FILED FEB-13,1919- 1,388,54=1 Patented Aug. 23, 1921.
3 SHEETSSHEET I.
H. C. WOODBURY. cmcun CONTROLLING APPARATUS.
APPLICATION FILED FEB. 13, I919.
Patented Aug. 23, 1921.
3 SHEETS-SHEET 2- H. C. WOODBURY.
' CIRCUIT CONTROLLING APPARATUS.
APPLICATION FILED FEB- 13. 1919.
1,388,541 Patented Aug. 23, 1921.
3 SHEETSSHEET 3. ,1 63 g%d 5. Z
UNITED STATES PATENT OFFICE 1.
HOMER C. WOODBU BY OF PROVIDENCE, RHODE ISLAND, ASSIGNOR T0 JOHN" SCHEMINGEB, JR., 0F PROVIDENCE, RHODE ISLAND.
CIRCUIT-CONTROLLING APPARATUS.
Specification of Letters Patent.
Patented Aug. 23,1921.
Application filed February 13, 1919. Serial No. 276,849.
To all whom it may concern:
Be it known that I, HOMER C. \VoooBURY, a citizen of the United States, residing at Providence, in the county of Providence and State of Rhode Island, have invented certain new and useful Improvements in Circuit- Controlling Apparatus; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.
This invention has for its object improved mechanism for automatically controlling the circuit of an electric motor, or other trans: lating device, to perform certain work in accordance with a variable demand for such work. It is designed primarily for use in connection with a rotary hydrocarbon burner in which organization a motor is used to operate the burner and the invention hereinafter described comprises convenient arrangement of circuit cont-rolling devices whereby the burner is put into or out of operation in accordance with temperature changes influenced by the burner. Its use, however, is not limited to this particular art, but it is capable of use 'in many other organizations as will be apparent to one skilled in the art. I
A thermostatic device, capable of movementin response to changes of temperature,
effects the closing of the circuit of an electromagnetic relay, the latter operating to open and close the motor circuitas well as to control its own circuit. The switching arrange ment under the control of the relay causes circuits to be made and broken in a definite sequence and by a novel combination of switch and operating elements to be hereinafter described in detail.
The accompanying drawings, forming a partof this specification. illustrate a practical embodiment of the invention.
In thesedrawings:
Figure 1 is a diagrammatic representation of the invention; showing its relation to the circuits which it controls and by which it is controlled Fig. 2 is a plan view of the electro-magnetic circuit controlling device;
Figs. 3 and -l are respectively side and end elevations of the same: i i
Fig. 5 is a detail view of the pawl and ratchet switch actuating mechanism:
Fig. 6 is a detail view of the rotary, cylindrical switch for the motor circuit, the contact' fingers of which are shown in dotted lines;
Fig. 7 is a view of the ratchet disk, carry-.
ing a second'switch element for controlling the circuit of the electro-magnetic actuating mechanism;
Figs. 8 and 9 are detail views showing the component parts of said last named switch;
- Fig. 10 is an assembled View of the two. sw1tches,-mounted on their common supporting shaft, and
Fig. 11 is a sectional View on the line 1111 of Fig. 7.
Referring now to these drawings, M is a motor, or other translating device, the circuit of which it is desired to control. It is assumed that current for operating the mo tor is supplied .from any suitable supply mains which form no part of the present invention.
The entire circuit controlling mechanism of this invention is conveniently mounted upon a panel or supporting plate P, withbinding-posts or terminals for all of the circuit connections, arranged so as to be readily accessible.
Included in the motor circuit, the connections for which to the panel board are numbered 1 and 2, is a rotary contact switch S, so
arranged that it may be operated to make or break the circuit of the motor M. The rotating element-of this switch comprises a cylinder, the peripheral surface of which is divided into diametrically opposite insulating and conducting areas, the latter being electrically connected. Resilient contact fingers or brushes (Z and d engage the periphery of the movable elements of the switch at diametrically opposite points and are either separated by insulation or electrically connected, depending upon the position occupied by said movable element. The transition points on the switch are arranged (see Fig. 6) so as to effect a quick making or breaking of the circuit. This is accomplished by providing an abrupt step on the periphery between areas of contact and insulation. The switch S is mounted upon and secured to a shaft A, but electrically insulated therefrom, in order to effectually prevent the relatively heavy currents of the motor circuit from coming into contact with anv other part of this circuit controlllng mechanism. The shaft A is mounted for r0- tation in bearings a and b rigidly supported upon the base plate or panel l The outer bearing (a is in an overhanging arm of a supporting element L, the extent of the 0ver-- hang being suiiicient to give clearance to all switch and actuating mechanism mounted upon the shaft. These details are clearly shown in Figs. 3 and 4:. i
The shaft A also carries a ratchet disk D, by means of which rotary motion may be imparted to the said shaft. To produce this motion the following elements are combined: An electro-magnet E is mounted upon the base-plate P, being held in position by bolt connection with an upright arm f oi a metallic supporting frame U. An armature 18 is pivotally supported at one end of the magnet upon a spring tongue G, which normally acts to hold the armature away from the pole-face of the magnet. A. vertical extension or lever H, is secured to the armature, and is provided at its upper end with a bale-like pawl K to engage and operate the ratchet disk D. The pawl is held in engagement with the ratchet by pressure oi: one end K of the pawl loop, against a backwardly bent portion in of the armature extension H. The usual adjustable stop in the nature of a screw N with lock-nut is provided to limit the backward movement of the armature.
The electro-magnet when energized will produce a vibratory movement of its armature l and extension H, which movement will transmit rotary motion to the shaft A through the pawl and ratchet mechanism in a manner readily apparent. This motion ot the shaft A resulting from energization of the magnet E would continue as long as the magnet circuit remains closed, with resultant alternate opening and closing'oi the circuit of the motor M, were no provision made for limiting the operation to that desired, namely, opening or closing the motor circuit. To limit the operation of the relay magnet, a second rotary switch is employed to secondarily control the circuit of the magnet in the manner hereinafter described. This switch is of disk-like form and mounted upon the shaft A upon whichis also mounted the ratchet disk D and rotates in unison therewith. It consists of a circular contact plate or disk R, which may be cut or stamped into the configuration shown in Fig. 9, having the bent up portions 7 and 1- and a segmental insulating disk R secured thereto. Spring-pressed fingers e and e cooperate with the movable element of the switch. These fingers are supported from and in electrical contact with the bindingposts 3 and 4:. In assembling this switch, the insulating disk is adjusted to the face of the contact disk R and by a partial rotation is interlocked with the upturned portions 1', r of the same, affording thus, a contact relative PI'OPOl't'lOIlS of exposed insulation and contact areas of the switch are such that by rotation of the switch through an angle of approximately the relation of the contact fingers or brushes 6, 0 will be reversed, that is, the brush which previously rested on a contact surface, will after the indicated movement, rest on an insulating 85 area, and the brush which rested on insulation, will engage a contact surface. This amount of angular displacement of the switch Q insures a movement of the switch S sutiicient to cause it to either make or break the circuit which it controls. AHSO- ciated with brushes 6 and e is a thermostatic or equivalent element T having a pointer or tongue i which moves in response to changes in temperature to engage one or the other of the fixed contact points r2 or 29". Each of these contact points is electrically connected to one of the brushes 6, c; t being connected to c and t with e. The fixed end at the thermostatic element is connected 10c permanently with one terminal of a primary or secondary battery B of suilicient ca pacity to properly energize the electro-magnet 1 The opposite terminal of the battery B is electrically connected with one end of the winding of the magnet ll, the other end of said winding being in electrical connection with the limiting stop N of the magnet armature in the usual manner. A shunt connection V is provided for the magnet l), which is of advantage in reducing the spa rking between the points of making and breaking the magnet circuit. due to the vibrating of its armature. The operation of the ircuit controlling device will now be apparent.
Referring to Fig. 1 the condition of the several circuits is as follows: The circuit of the motor or other translating device M is interrupted at the switch S. The thermostat T makes contact at t which connects with the brush a. Since the latter rests on an insulating arca R of the disk switch the circuit of the electro-magnet l] is also interrupted and the controlling device remains inactive. Upon a change in temperature, however, the thermostat T, moving automatically in response to such change, may swing its pointer 15 into engagement with the contact 16 Current from the battery B can then flow through the thermostat to the all?) insane-i thence back to the opposite pole of the battery. The relay being energized, a vibratory motion will be imparted to the lever H, and through the pawl and ratchet mechanism the shaft A will be rotated to operate in sequence, the switch S and the disk switch. Contact is first established between the,brushes oi the switch S and it is then necessary to stop the operation of the relay in order to maintain this circuit. This is effected through the disk switch. The con tact finger 6 through which the magnet circuit was established will have passed off from a contact area of the disk switch immediately alter the. motor circuit is made through the switch S. "lh1s results in break mg oithe magnet or relay clrcuit and consequent stopping of the switch actuating mechanism at the desired point. The second contact fingere will have passed on to a contact area oli its switch and the circuit controlling device will then be in readiness to respond to changed conditions to restore the former position of the switches, when the thermostat registering such a change will move to again engage with the contact Each closing therefore of the relay circuit by the thermostat making contact with either IE or t will result in such operation oi the relay as will eii'ect a change in the circuit of the motor M and thereupon the relay circuit will be broken to limit its further action until the thermostat engages the other contact whereupon the relay will be called upon to res-tore the motor circuit to its former condition Having thus described my invention, what I claim as new and desire to secure by Let tors Patent of the United States, is
i. in circuit controlling apparatus for regulating the supply or electric energy to a motor-operated hydrocarbon burner, the combination of a rotary switch in the circuit of said motor, an electro-magnetic relay for operating said switch to eilcct the making or breaking of the motor circuit, a thermostat for controlling the relay circuit, and a second rotary switch also operated by the relay tobreak the relay circuit, after the operation of making or breaking the motor circuit shall have been completed, substantially as described.
2. A circuit controlling device comprising a plurality of rotary contact switches mounted upon a common shaft andadapted to control as many independent electric circuits, a pawl and ratchet actuating mechasm for g'said shaft, an electromagnet for actuating said pawl and ratchet dezvice; the circuit of said magnet being secondarily controlled by one of the rotary contact switches, and circuit controlling means responsive to temperature changes for primarily closing the magnet circuit to eilect the operation of all the rotary switches in such sequence that the rotary switch of the magnet circuit will break this circuit only after such movement of the other switches as is necessary to effect a change in the circuit which they control, substantially as described.
3. A circuit controlling device comprising a rotary contact switch for controlling the making or breaking of a motor circuit, a shaft upon which said switch is carried, a ratchet disk also mounted upon said shaft, a spring-pressed pawl adapted to engage said disk and transmit motion thereto, an electromagnet having a vibratory armature for operating said pawl, a second rotary contact switch mounted upon said shaftand adapted to turn with the ratchet disk; the areas of contact and insulation on said last named switch being substantially equal, two contact areas of like extent being separated by insulation areas of similar extent, two resilient contact fingers engaging the surface of said switch at points separated by a distanc corresponding to the length of one contact area, and automatic temperature controlled means for closing the magnet circuit through one of the contact lingers and conducting element of the switch associated therewith, to operate the circuit controlling device to the extent of producing an angular displacement of the shaft carrying the rotary switches equal to an angle of approximately 90, by which movement of the shaft a change is made by the rotary switch in the motor circuit, followed by a breaking of the magnet circuit at the second rotary switch,
d. A thermostatically controlled electromagnetic circuit controlling device including a motor circuit and rotary switch capable of operation to make or break said circuit, a shaft mounted in suitable bearings and carrying the movable element of said switch but electrically insulated therefrom, a second rotary switch also carried by the shaft and so positioned thereon that the conducting areas of the two switches are relatively displaced by an angle of approximately 90, tw o resilient contact fingers engaging the second rotary switch at separated circumferential points, a lead from each contact finger adapted to be connected at one terminal of athermostat, the movable element of which n is designed to make contact with one or the other of these terminals, an electro-magnet the circuit of which is controlled by said second rotary switch, and pawl and ratchet mechanism operated by the magnet to pro- 13o duce a measured rotation of the shaft suflithe circuit including the last-named contact 10 cient to operate the rotary switches to effect by the thermostat, substantially as described. a desired change in the motor circuit and to In testimony whereof I aflix my signature break the magnet circuit through one set in the presence of two Witnesses.
of contacts on the second rotary switch and imultaneously establish another connection 7 HOMER WOOD BURY for the magnet through this switch to leave Witnesses: the circuit controlling mechanism in condi- B. M. OFFUTI,
tion to be again actuated by completion of THoMAs F. BURKE.
US276849A 1919-02-13 1919-02-13 Circuit-controlling apparatus Expired - Lifetime US1388541A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US276849A US1388541A (en) 1919-02-13 1919-02-13 Circuit-controlling apparatus

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US276849A US1388541A (en) 1919-02-13 1919-02-13 Circuit-controlling apparatus

Publications (1)

Publication Number Publication Date
US1388541A true US1388541A (en) 1921-08-23

Family

ID=23058315

Family Applications (1)

Application Number Title Priority Date Filing Date
US276849A Expired - Lifetime US1388541A (en) 1919-02-13 1919-02-13 Circuit-controlling apparatus

Country Status (1)

Country Link
US (1) US1388541A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2775047A (en) * 1952-01-23 1956-12-25 Whirlpool Seeger Corp Drier control
US2894096A (en) * 1957-06-25 1959-07-07 Gen Telephone Lab Inc Rotary switch
US3277412A (en) * 1963-01-19 1966-10-04 Acena Alfonso Romera De La Electromagnetic switch having intermittent operation

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2775047A (en) * 1952-01-23 1956-12-25 Whirlpool Seeger Corp Drier control
US2894096A (en) * 1957-06-25 1959-07-07 Gen Telephone Lab Inc Rotary switch
US3277412A (en) * 1963-01-19 1966-10-04 Acena Alfonso Romera De La Electromagnetic switch having intermittent operation

Similar Documents

Publication Publication Date Title
US1388541A (en) Circuit-controlling apparatus
US3302001A (en) Time-temperature control devices
US1978947A (en) Time controlled circuit controller
US1422625A (en) Electrical control apparatus
US2231218A (en) Switch
US2325094A (en) Furnace control apparatus
US1704300A (en) Electric-circuit controller
US1355847A (en) Thermal time-switch
US1569450A (en) Automatic switch
US2305974A (en) Magnetic coupling
US910478A (en) Rheostat.
US2459349A (en) Motor control system with latching relays
US982346A (en) Electrically-operated automatic cut-out.
US2113617A (en) Relay
US2453251A (en) Motor-operated push-button tuner
US3495082A (en) Switching module for combined motor and lamp control circuits for sewing machines
US1124809A (en) Circuit-controlling apparatus.
US1806377A (en) Friction switch mechanism
US773182A (en) Automatic electric switch.
US1716951A (en) Electric switch and means for operating same
US2459350A (en) Automatic reversing control for electric motors
US2369715A (en) Fan stopping device
US1267069A (en) Electrically-controlled temperature-regulator.
US1041716A (en) Selective time-limit-controlling device for electric switches.
US505063A (en) ramien