[go: up one dir, main page]

US2916572A - Electric switch responsive to the movements of the human body during sleep - Google Patents

Electric switch responsive to the movements of the human body during sleep Download PDF

Info

Publication number
US2916572A
US2916572A US737422A US73742258A US2916572A US 2916572 A US2916572 A US 2916572A US 737422 A US737422 A US 737422A US 73742258 A US73742258 A US 73742258A US 2916572 A US2916572 A US 2916572A
Authority
US
United States
Prior art keywords
plunger
casing
opening
movements
switch
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
US737422A
Inventor
Ulanet George
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 US737422A priority Critical patent/US2916572A/en
Application granted granted Critical
Publication of US2916572A publication Critical patent/US2916572A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H35/00Switches operated by change of a physical condition
    • H01H35/003Switches operated by other part of human body than hands
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S200/00Electricity: circuit makers and breakers
    • Y10S200/02Body attached switches

Definitions

  • This invention relates to an electric switch and especially to an electric switch responsive to the movements of the human body during sleep.
  • a further object is to provide an electric switch which will not only turn the electric device 011 after the person falls asleep but will also prevent the device from being turned on again by subsequent movements of the body of the sleeping person.
  • subject switch is constituted of a pair of normally open spring contact members in a casing, the contact members being connected in series with the electric device.
  • a plunger actuated for example by the head of a sleeping person, and reciprocal in the casing closes the spring contact members and the circuit to the electric device when the person retires. Any movement of the head of the person after falling asleep will release the plunger and open the contact members to break the circuit to the electric device.
  • a second plunger in operable engagement with the first mentioned plunger locks the latter in the normally open position of the spring contact members so that subsequent movements of the head of the sleeping person will not again close the circuit to the electric device.
  • FIG. 1 is a top view of the switch constructed in accordance with the principles of this invention.
  • FIG. 2 is a side view of the switch shown in Figure 1;
  • Figure 3 is a sectional view along the line 3-3 of Fig ure 1;
  • Figure 4 is a bottom view of the switch shown in Figure 1 and in part section to more clearly show the internal construction
  • Figure 5 is a wiring diagram.
  • reference numeral indicates the switch constituted in part of the casing 11.
  • the casing 11 is formed of a top member 12, and end members 13 and 14 which may be formed integral with the top member as illustrated or otherwise.
  • the casing is further formed of the side members '15 and 16 secured ice along corresponding edges of the top and end members, and a bottom member 17.
  • the bottom member 17 is removably secured to the corresponding edges of the side and end members by any suitable fasteners 18a, numerals 19a in Figure 4 indicating threaded openings from which the fasteners 18a have been removed.
  • an opening 18 (Figs. 1, 3, and 4) of substantially square cross section.
  • FIG. 1 Through the end member 13 is another opening 19 (Figs. 1, 3, and 4) which is of maximum diameter from the outer end of the opening inwardly substantially to a point 20 (Fig. 1) and of minimum diameter from the point 20 inwardly in intersect at an angle the previously mentioned opening 18 of square cross section.
  • the inner portion of the opening 19 having minimum diameter is concentric with that portion of the opening '19 having maximum diameter.
  • a pair of normally open springcontact members 21 and 22 (Fig. 3) each of which is fixed at one end in the casing by a screw 23 (Figs. 1, 3, and 4).
  • Numeral 24 (Fig. 3) indicates an insulating collar placed around the screw 23 while numerals 25 and 26 show terminals for connecting the spring contact members in series with the electric device (not shown) and an electrical energy source.
  • Numerals 27, 28, and 29 are spacers for insulating the fixed ends of the contact members and their terminals from each other and, if necessary, from the casing. From the fixed ends, the contact members 21 and 22 extend forwardly in spaced arrangement and are substantially aligned with the previously mentioned opening 18 of square cross section through the top member 12. Each contact member has a normally open contact point adjacent the free end as illustrated.
  • a plunger 30 Reciprocal through the opening 18 of square cross section in the top member 12 is a plunger 30 as must clearly seen in Figure 3, the outer 'end of the plunger protruding above the top member 12 and the inner end designed for operable engagement with the most proximate spring contact member 21.
  • the outwardly protruding end of the plunger 30 is provided with a cap 31 which may be formed integral therewith or otherwise secured thereto in any known manner.
  • a spring 32 (Fig. 3) is placed between the inner surface of the cap 31 and the top member 12 of the casing. A recess may be formed in the top member 12 as shown in Figure 3 to more thoroughly secure the spring.
  • a transverse slot 41 (Fig. 3) is made through the plunger 30 while through the slot is a pin 42 (Figs. 1 and 4) or the like which is inserted through any suitable opening 43 (Figs. 1 and 4) made through the top member 12 and aligned with the slot 41.
  • a second plunger 33 Reciprocal in the previously mentioned opening 19 (Figs. 1, 3, and 4) in the end member 13 is a second plunger 33 (Fig. 4) which extends from the knob 34 on the outer end thereof inwardly through the opening 19 where the diameter is at a maximum, and thence through that portion of the opening having minimum diameter for operable engagement in a recess 38 (Fig. 3) formed in the first mentioned plunger 30.
  • a spring 37 (Figs. 1 and 4) is placed around the plunger 33 between the ends thereof, the spring being held adjacent the inner end of the plunger by a collar 35 (Fig. 4). Any known means may be used to fasten the collar to the plunger with the collar being seated against the inner end of that portion of the opening 19 having maximum diameter when the inner end of the plunger is in the recess 38 (Fig. 3) of the first mentioned plunger 30.
  • the opposite or outer end of the spring 37 is held in the opening 19 by a screw 39 (Figs. 1, 3, and 4) threaded into the outer end of the opening 19. Obviously the spring 3 37 is under tension and the plunger 33 is reciprocal through the screw 39.
  • a radio or television set or other electric device (not shown) is plugged into a receptacle 36 (Fig. 1), and the plug 40 inserted in any suitable outlet in the supply of electrical energy.
  • the switch is then placed, for example, under the pillow of the person about to retire.
  • the knob 34 Figs. 1 and 3
  • the plunger 33 By pulling outwardly on the knob 34 (Figs. 1 and 3) f the plunger 33, the first mentioned plunger 30 will be released from the second mentioned plunger 33 and the weight of the head of the person on the pillow will move the plunger 30 inwardly in operable engagement with the spring contact member 21 to close the contact points of the contact members 21 and 22 and turn on the electric device.
  • the plunger 30 will be released, the spring 32 forcing it outwardly with the contact points of the spring contact members 21 and 22 moving to the normally open position to break the circuit to the electric device.
  • the inner end of the second mentioned plunger 33 will then reenter the recess 38 of the plunger 30 to lock it in the open position of the contact points and thus prevent the electric device from being turned on again after another movement of the head of the sleeping person on the pillow.
  • An electric switch responsive to the movements of the human body during sleep in combination with an electric device and a source of electrical energy, the switch comprising a casing, a pair of normally open spring contact members for the casing, means connecting the contact members in series with the device and the source of electrical energy, a plunger reciprocal in the casing and in operable engagement with one contact member, and means securely locking the plunger in the normally open position of the contact members after being closed, said last mentioned means comprising a second plunger in operable engagement with the first mentioned plunger, and means on the last mentioned plunger manually unlocking the plungers.
  • An electric switch for breaking the circuit to an electric device when a person falls asleep, the switch comprising a casing, a pair of normally open spring contact members disposed in the casing, means connecting the spring contact members in series with the electric device, and transverse means under inwardly directed tension in operable engagement with the first mentioned means whereby the contact members after being closed are locked in the normally open position thereof, the transverse means being disengaged from the first mentioned means by applying directly thereto a manually exerted and outwardly directed force.
  • a switch for breaking the circuit to an electric device when a person falls asleep comprising a casing, the casing having at least a top member and end members secured along corresponding edges, the top member halving an opening of square cross section formed therein, a pair of normally open spring contact members disposed in the casing, means fixing one end of each contact member in the casing with the fixed ends insulated from each other and from the casing and with the free ends extended forwardly of the fixed ends in spaced arrangement and substantially aligned with the opening in the top member, a plunger reciprocal through the opening in the top member and in operable engagement with the most proximate contact member, the plunger having a recess formed therein, outwardly directed spring tension means maintaining the plunger in disengagement with the most proximate contact member, a second plunger reciprocal through an end member at an angle to the first mentioned plunger and in operable engagement with the recess therein, and means maintaining the second mentioned plunger under inwardly directed tension in the recess.
  • a switch according to claim 3 in which an opening of circular cross section is formed in an end member at an angle to the opening of square cross section and connecting therewith, the opening of circular cross section. having maximum diameter adjacent the outer edge of the casing and minimum concentric diameter when connecting to the opening of square cross section, the second mentioned plunger being reciprocal through the opening of minimum diameter.
  • a switch according to claim 3 in which the tension means maintaining the second mentioned plunger under tension in the recess of the first mentioned plunger comprises a spring member, the spring member being secured at the inner end thereof by a collar disposed on the second mentioned plunger, and at the outer end by a screw through which said plunger is reciprocal.
  • An electric switch comprising, in combination, a casing, the casing having a top member and means for supporting the top member, the top member further having an opening formed therein, a pair of normally open spring contact members disposed in the casing, the fixed ends being insulated from each other and from the casing with the free ends extended forwardly of the fixed ends in spaced arrangement and substantially aligned with the opening, a plunger reciprocal through the opening and in operable engagement with the most proximate contact member, the plunger having an aperture formed therein.
  • a second plunger under inwardly directed tension transversely disposed in the casing and in operable engage ment with the aperture in the normally open position of the contact members, means maintaining the aperture and second mentioned plunger in alignment, and a knob disposed on the last mentioned plunger whereby said plunger can be manually released from the aperture.

Landscapes

  • Push-Button Switches (AREA)

Description

G. ULANET 2,916,572 ELECTRIC SWITCH RESPONSIVE TO THE MOVEMENTS OF THE HUMAN BODY DURING SLEEP Filed May 23, 1958 INVENTOR. GEO/Q65 ULANET BY MA/ 19%;,
ATTORNEY United States Patent ELECTRIC SWITCH RESPONSIVE TO THE MOVE- MENTS OF THE HUMAN BODY DURING SLEEP George Ulanet, Maplewood, NJ. 7
Application May 23, 1958, Serial No. 737,422
6 Claims. (Cl. 200-52) This invention relates to an electric switch and especially to an electric switch responsive to the movements of the human body during sleep.
Heretofore, electric devices such as radio and television sets have been connected in a circuit with a timing device which is set to shut the set off at a predetermined hour when the person expects to fall asleep. Such preselected hour is, of course, pure conjecture so that the device may continue to operate long after the person actually falls asleep thereby adding to the discomfort of others.
It is an object of the instant invention to provide an electric switch responsive to the movements of the human body during sleep, the switch breaking the circuit to the electric device by the movements of the body after falling asleep.
A further object is to provide an electric switch which will not only turn the electric device 011 after the person falls asleep but will also prevent the device from being turned on again by subsequent movements of the body of the sleeping person.
Other objects of the instant invention will become ap- K parent in the course of the following detailed description.
In the attainment of the aforesaid objectives, subject switch is constituted of a pair of normally open spring contact members in a casing, the contact members being connected in series with the electric device. A plunger, actuated for example by the head of a sleeping person, and reciprocal in the casing closes the spring contact members and the circuit to the electric device when the person retires. Any movement of the head of the person after falling asleep will release the plunger and open the contact members to break the circuit to the electric device. With the release of the plunger and the Opening of the circuit, a second plunger in operable engagement with the first mentioned plunger locks the latter in the normally open position of the spring contact members so that subsequent movements of the head of the sleeping person will not again close the circuit to the electric device.
The invention will appear more clearly from the following detailed description when taken in conjunction with the accompanying drawings showing by way of example the preferred embodiment of the inventive concept.
In the drawings: a
Figure 1 is a top view of the switch constructed in accordance with the principles of this invention;
Figure 2 is a side view of the switch shown in Figure 1;
Figure 3 is a sectional view along the line 3-3 of Fig ure 1;
Figure 4 is a bottom view of the switch shown in Figure 1 and in part section to more clearly show the internal construction; and
Figure 5 is a wiring diagram.
In Figures 1-4, reference numeral indicates the switch constituted in part of the casing 11.
The casing 11 is formed of a top member 12, and end members 13 and 14 which may be formed integral with the top member as illustrated or otherwise. The casing is further formed of the side members '15 and 16 secured ice along corresponding edges of the top and end members, and a bottom member 17. The bottom member 17 is removably secured to the corresponding edges of the side and end members by any suitable fasteners 18a, numerals 19a in Figure 4 indicating threaded openings from which the fasteners 18a have been removed.
Through the top member 12 is an opening 18 (Figs. 1, 3, and 4) of substantially square cross section.
Through the end member 13 is another opening 19 (Figs. 1, 3, and 4) which is of maximum diameter from the outer end of the opening inwardly substantially to a point 20 (Fig. 1) and of minimum diameter from the point 20 inwardly in intersect at an angle the previously mentioned opening 18 of square cross section. The inner portion of the opening 19 having minimum diameter is concentric with that portion of the opening '19 having maximum diameter.
Within the casing 11 is a pair of normally open springcontact members 21 and 22 (Fig. 3) each of which is fixed at one end in the casing by a screw 23 (Figs. 1, 3, and 4). Numeral 24 (Fig. 3) indicates an insulating collar placed around the screw 23 while numerals 25 and 26 show terminals for connecting the spring contact members in series with the electric device (not shown) and an electrical energy source. Numerals 27, 28, and 29 are spacers for insulating the fixed ends of the contact members and their terminals from each other and, if necessary, from the casing. From the fixed ends, the contact members 21 and 22 extend forwardly in spaced arrangement and are substantially aligned with the previously mentioned opening 18 of square cross section through the top member 12. Each contact member has a normally open contact point adjacent the free end as illustrated.
Reciprocal through the opening 18 of square cross section in the top member 12 is a plunger 30 as must clearly seen in Figure 3, the outer 'end of the plunger protruding above the top member 12 and the inner end designed for operable engagement with the most proximate spring contact member 21. The outwardly protruding end of the plunger 30 is provided with a cap 31 which may be formed integral therewith or otherwise secured thereto in any known manner. To maintain the plunger under outwardly directed tension, a spring 32 (Fig. 3) is placed between the inner surface of the cap 31 and the top member 12 of the casing. A recess may be formed in the top member 12 as shown in Figure 3 to more thoroughly secure the spring. To prevent the plunger 30 from falling out of the casing 11, a transverse slot 41 (Fig. 3) is made through the plunger 30 while through the slot is a pin 42 (Figs. 1 and 4) or the like which is inserted through any suitable opening 43 (Figs. 1 and 4) made through the top member 12 and aligned with the slot 41.
Reciprocal in the previously mentioned opening 19 (Figs. 1, 3, and 4) in the end member 13 is a second plunger 33 (Fig. 4) which extends from the knob 34 on the outer end thereof inwardly through the opening 19 where the diameter is at a maximum, and thence through that portion of the opening having minimum diameter for operable engagement in a recess 38 (Fig. 3) formed in the first mentioned plunger 30. To maintain the second mentioned plunger 33 under inwardly directed tension,
, a spring 37 (Figs. 1 and 4) is placed around the plunger 33 between the ends thereof, the spring being held adjacent the inner end of the plunger by a collar 35 (Fig. 4). Any known means may be used to fasten the collar to the plunger with the collar being seated against the inner end of that portion of the opening 19 having maximum diameter when the inner end of the plunger is in the recess 38 (Fig. 3) of the first mentioned plunger 30. The opposite or outer end of the spring 37 is held in the opening 19 by a screw 39 (Figs. 1, 3, and 4) threaded into the outer end of the opening 19. Obviously the spring 3 37 is under tension and the plunger 33 is reciprocal through the screw 39.
In operation: A radio or television set or other electric device (not shown) is plugged into a receptacle 36 (Fig. 1), and the plug 40 inserted in any suitable outlet in the supply of electrical energy. The switch is then placed, for example, under the pillow of the person about to retire. By pulling outwardly on the knob 34 (Figs. 1 and 3) f the plunger 33, the first mentioned plunger 30 will be released from the second mentioned plunger 33 and the weight of the head of the person on the pillow will move the plunger 30 inwardly in operable engagement with the spring contact member 21 to close the contact points of the contact members 21 and 22 and turn on the electric device. With. any substantial movement of the head of the person on the pillow after falling asleep, the plunger 30 will be released, the spring 32 forcing it outwardly with the contact points of the spring contact members 21 and 22 moving to the normally open position to break the circuit to the electric device. The inner end of the second mentioned plunger 33 will then reenter the recess 38 of the plunger 30 to lock it in the open position of the contact points and thus prevent the electric device from being turned on again after another movement of the head of the sleeping person on the pillow.
While only one form of subject switch has been described and illustrated, other forms are possible within the scope of the appended claims.
What is claimed is:
1. An electric switch responsive to the movements of the human body during sleep, in combination with an electric device and a source of electrical energy, the switch comprising a casing, a pair of normally open spring contact members for the casing, means connecting the contact members in series with the device and the source of electrical energy, a plunger reciprocal in the casing and in operable engagement with one contact member, and means securely locking the plunger in the normally open position of the contact members after being closed, said last mentioned means comprising a second plunger in operable engagement with the first mentioned plunger, and means on the last mentioned plunger manually unlocking the plungers.
2. An electric switch for breaking the circuit to an electric device when a person falls asleep, the switch comprising a casing, a pair of normally open spring contact members disposed in the casing, means connecting the spring contact members in series with the electric device, and transverse means under inwardly directed tension in operable engagement with the first mentioned means whereby the contact members after being closed are locked in the normally open position thereof, the transverse means being disengaged from the first mentioned means by applying directly thereto a manually exerted and outwardly directed force.
3. A switch for breaking the circuit to an electric device when a person falls asleep, the switch comprising a casing, the casing having at least a top member and end members secured along corresponding edges, the top member halving an opening of square cross section formed therein, a pair of normally open spring contact members disposed in the casing, means fixing one end of each contact member in the casing with the fixed ends insulated from each other and from the casing and with the free ends extended forwardly of the fixed ends in spaced arrangement and substantially aligned with the opening in the top member, a plunger reciprocal through the opening in the top member and in operable engagement with the most proximate contact member, the plunger having a recess formed therein, outwardly directed spring tension means maintaining the plunger in disengagement with the most proximate contact member, a second plunger reciprocal through an end member at an angle to the first mentioned plunger and in operable engagement with the recess therein, and means maintaining the second mentioned plunger under inwardly directed tension in the recess. 7
4. A switch according to claim 3 in which an opening of circular cross section is formed in an end member at an angle to the opening of square cross section and connecting therewith, the opening of circular cross section. having maximum diameter adjacent the outer edge of the casing and minimum concentric diameter when connecting to the opening of square cross section, the second mentioned plunger being reciprocal through the opening of minimum diameter.
5. A switch according to claim 3 in which the tension means maintaining the second mentioned plunger under tension in the recess of the first mentioned plunger comprises a spring member, the spring member being secured at the inner end thereof by a collar disposed on the second mentioned plunger, and at the outer end by a screw through which said plunger is reciprocal.
6. An electric switch comprising, in combination, a casing, the casing having a top member and means for supporting the top member, the top member further having an opening formed therein, a pair of normally open spring contact members disposed in the casing, the fixed ends being insulated from each other and from the casing with the free ends extended forwardly of the fixed ends in spaced arrangement and substantially aligned with the opening, a plunger reciprocal through the opening and in operable engagement with the most proximate contact member, the plunger having an aperture formed therein. a second plunger under inwardly directed tension transversely disposed in the casing and in operable engage ment with the aperture in the normally open position of the contact members, means maintaining the aperture and second mentioned plunger in alignment, and a knob disposed on the last mentioned plunger whereby said plunger can be manually released from the aperture.
References Cited in the file of this patent UNITED STATES PATENTS 1,834,467 Mapes et al. Dec. 1, 1931 2,010,233 Hopkins et al. Aug. 6, 1935 FOREIGN PATENTS 483,677 Germany Oct. 4, 1929
US737422A 1958-05-23 1958-05-23 Electric switch responsive to the movements of the human body during sleep Expired - Lifetime US2916572A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US737422A US2916572A (en) 1958-05-23 1958-05-23 Electric switch responsive to the movements of the human body during sleep

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US737422A US2916572A (en) 1958-05-23 1958-05-23 Electric switch responsive to the movements of the human body during sleep

Publications (1)

Publication Number Publication Date
US2916572A true US2916572A (en) 1959-12-08

Family

ID=24963857

Family Applications (1)

Application Number Title Priority Date Filing Date
US737422A Expired - Lifetime US2916572A (en) 1958-05-23 1958-05-23 Electric switch responsive to the movements of the human body during sleep

Country Status (1)

Country Link
US (1) US2916572A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3054868A (en) * 1959-03-30 1962-09-18 Phillians Edward Sleep preventing alarm
DE1285040B (en) * 1966-02-10 1968-12-12 Scovill Manufacturing Co Safety switch for electrical tools that can be activated by pressure

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE483677C (en) * 1928-12-07 1929-10-04 Julius Schneider Dr Switch for motor vehicles
US1834467A (en) * 1929-09-25 1931-12-01 Herman C Mapes Arm signal switch
US2010233A (en) * 1930-01-13 1935-08-06 American District Telegraph Co Electric call and alarm system

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE483677C (en) * 1928-12-07 1929-10-04 Julius Schneider Dr Switch for motor vehicles
US1834467A (en) * 1929-09-25 1931-12-01 Herman C Mapes Arm signal switch
US2010233A (en) * 1930-01-13 1935-08-06 American District Telegraph Co Electric call and alarm system

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3054868A (en) * 1959-03-30 1962-09-18 Phillians Edward Sleep preventing alarm
DE1285040B (en) * 1966-02-10 1968-12-12 Scovill Manufacturing Co Safety switch for electrical tools that can be activated by pressure

Similar Documents

Publication Publication Date Title
US3171183A (en) Utility fastener
US2899841A (en) Control knobs
US2955272A (en) Television and electric appliance lock
US2916572A (en) Electric switch responsive to the movements of the human body during sleep
US2190363A (en) Electrical fitting for cord sets
US2307592A (en) Electrical locking connector
US5277600A (en) Electrical plug safety lock
US2443509A (en) Connector
US2282967A (en) Electrical connection circuit breaker
US3466715A (en) Releasable plug-and-socket fastener
US2289128A (en) Thermostatic control device
US3041694A (en) Fastening device
US1561495A (en) Electrical connecter
US1951981A (en) Electrical connection
US2718726A (en) Toy bank
US2234876A (en) Circuit maker and breaker
US2500184A (en) Electrical apparatus
US2483645A (en) Thermal circuit breaker
DE800061C (en) Alarm clock thermometer
US2175472A (en) Receptacle
US2439462A (en) Electric plug and socket latch
US2511236A (en) Heat responsive switch
US1638439A (en) Circuit closer
US2129309A (en) Ejector fuse plug
US2262848A (en) Electric fuse