US1114680A - Electric switch. - Google Patents

Electric switch. Download PDF

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Publication number
US1114680A
US1114680A US65781411A US1911657814A US1114680A US 1114680 A US1114680 A US 1114680A US 65781411 A US65781411 A US 65781411A US 1911657814 A US1911657814 A US 1911657814A US 1114680 A US1114680 A US 1114680A
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Prior art keywords
cam
contact
electric switch
movable
contact member
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US65781411A
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Harry W Denhard
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Cutler Hammer Manufacturing Co
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Cutler Hammer Manufacturing Co
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H5/00Snap-action arrangements, i.e. in which during a single opening operation or a single closing operation energy is first stored and then released to produce or assist the contact movement
    • H01H5/04Energy stored by deformation of elastic members
    • H01H5/045Energy stored by deformation of elastic members making use of cooperating spring loaded wedging or camming parts between operating member and contact structure
    • 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
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T74/00Machine element or mechanism
    • Y10T74/18Mechanical movements
    • Y10T74/18856Oscillating to oscillating
    • Y10T74/18864Snap action

Definitions

  • y invention relates to electric switches. It has among its objects to provide an 1mproved electric switch.
  • a further object of my invention is to provide an electric switch adapted to make or break one or more circuits or one or more branches of a single circuit, the switch mechanism being adapted to be operated with a quick snapaction.
  • Figure 1 shows a top plan view of this form of vation of the same.
  • Fig. 3 shows a central sectional view through the same.
  • the operating member 2 is arranged to rotate about the shaft or spindle 3 and is provided with a serrated active surface including a plurality of'radially extending cam surfaces 8 arranged about a central opening 9 and having oppositely sloping sides, the width of which preferably increase toward the periphery of the cam member.
  • two oppositely located cam surfaces 8 have extensions 10 giving them a greater radius than their fellows as shown in Figs. 1 and 4.
  • the cam member is forme of a single sheet of metal andthe handle 2 is stamped out of the same sheet of metal from which the. surfaces are formed'.. It is obviousthat this handle may be operated either manually, electrically or by connection to any suitable automatic de: v1ce.-
  • the cam surfaces 8- are normally held down upon the upper surfaces of rounded bearing surfaces 11 on a stationary member 12 by means of a s ring 4 whose upper end is held upon the s aft as by a pin 13 and Washer 14.
  • the'member 12 is made up in the form of a diskprovided with .a plurality of spaced steel balls seated upont e upper surface of the same as shown in Fig. steel balls serve to ingf bearin surfaces.
  • I berQIQ isfpreferably provided with a central opening of a type which prevents it from rotatingabout the shaft'B
  • the disk 12 is in a 1rferredform provided withv asquagre or ot erirregular shaped opening 15 in its center which is tion'or square Jsectionj 16 formed intermediate the. ends ofthe v spind le 3 as shi w'n in j fn apreferred 'foirmfihe inovable contact member 5 ismounted beneath the stationary membervlfi and isarranged to.,be freely rotatable the lower er'id' offthe shaft or spindle 3'. .In a prefer'red con tr ction; the 1 fl1 e be1!.
  • the s io y'imeiir) arranged to. house a proje -i gether by suitable screws, rivets or other devices 20 preferably arranged to clamp the conducting parts snugly between the sheets of insulation. If desired I may use more than two conducting plates.
  • the top plate of the contact member 5 is preferably provided with upwardly extending triangular or peaked projections 21, while the contact plate 17 is preferably provided with an enlarged body portion preferably substantially circular and with radially extending integral contacts 22 and 23. In a preferre form these contact members are made resilient and are constructed as shown in Fig.
  • the contact member 18 is preferably provided with extensions or contact arms 24: and 25.
  • the contact arms 24 and 25 are arranged substantially at right angles to each other, while the contact arms 22 and 23 are arranged substantially at an angle of sixty degrees from each other. If desired, however, these various contact arms may be so located in the movable contact member as to permit them to be adjusted at any desired position.
  • the contact members 17 and 18 may if desired be stamped from single sheets of metal and the contact arms may be made to extend at any desired angles with respect to each other.
  • the contacts 23 and 25 are slightly shorter than the contact arms 22 and 24.
  • the contact arms 22 and 24 are arranged to make contact at the contacts 6 which are arranged in an arc of greater radius than the arc of the contacts 7 which are preferably arranged to be engaged by the contact arms 23 and 25.
  • the contacts 6 are shorter than the contacts 7 and are spaced apart from each other by an approximately equal distance; an additional stud 26 being pro vided intermediate certain of the same.
  • the contacts 6 are also ar-- ranged as shown in Fig. 2 being provided with upwardly extending portions 27 having flat contact surfaces 28 arranged sub-- stantially at right angles to the body of the contact members 6 and in a different plane.
  • the contact members 7 are arranged flat upon the surface of the base 1 and are attached to the same by means of suitable bolts or other devices 29.
  • these contact -members are arranged concentrically as shown and are of substantially the same length.
  • a plate 30 corresponding to the upper spindle 3 is preferably housed or seated in a in the plate 31 in.
  • the lower end of the shaft is preferably flattened and squared as shown at 33 in Fig. 3 and the plate 31 is provided with a suitable recess arranged to receive the end 33.
  • the handle 2 When it is desired to operate a switch of. the construction shown in the accompanying drawings, the handle 2 is moved to the right or left by any suitable means. Any suitable means may be provided to limit this movement if this is deemed necessary. Assuming that the movement of the handle is to the left or downward as shown in Fig. 1, the cam surfaces 8. are moved to the left. These cam surfaces ride up over'the surfaces of the balls 11 and the extensions 10 ride up over the peaked projections 21. This tends to compress'the spring 4. When the edge of the-shorter cam surface 8 is passed over the crest of the nearest ball 11, the spring 4: tends to throw the cam member downward along the opposite slope of the cam.
  • improved construction is especially adapted to change the circuit connections from series to parallel or vice versa as desired in electric heating devices in order to give three breaks.
  • the movement of the switch in each one of its steps is positive, the handle being moved and the switch then automatically throwing with a quick snap action.
  • the movable contact member is kept in a fixed relation with the same by the engagement of its projections with the extensions.
  • the contacts may be moved about the spindle by a series of movements of the handle which are distinct from each other, the contact parts in each instance being moved to their new position with a quick snap action.
  • the stationary contacts and the movable contacts I am able to provide a switch which is very compact and which acts to make or break a circuit with a quick snap action so that there is a minimum of sparking.
  • the parts are of a rugged con struction well adapted to withstand long use in service. Further the parts are effectually insulated from each other and are of a type which may be readily and cheaply manufactured.
  • a stationary member in combination, a movable member, said. members having cam parts resiliently held in engagement to accelerate said movable member upon operation thereof, a movable contact member, and a connection between said contact member and said movable member for imparting movement from the latter to the former but only after acceleration of said latter member.
  • a rotary contact member in combination, a rotary contact member, a rotary operating member, cooperating cam faces on said 'members, a non-rotary member, co6perating cam faces on said non-rotary member and said 0 crating member, and resilient means for oldin 'said-operating member in engagement with said non-rotary member and said contact member.
  • a rotary contact member in combination, a rotary contact member, a rotary operating member, said members having engaging parts permitting a combined rotary and axial movement of said operating member in one direction independently ofsaid con-- tact member but causing'operation of said contact member upon a reverse axial move-' ment of said operating member, and means including a non-rotary cam for causing said axial movements of said operating member when rotated and for accelerating said reverse axial movement of said operating member.
  • a rotary operating member in a rotary contact member, a rotary operating member, said members having engaging parts permitting a combined rotary and axial movement of said operating member independently of said contact member but insuring operation of said contact member with said operating member upon a reverse axial and continued rotar movement of the later, resilient means biasing said 0 crating member in said reverse axial direction, and a stationary cam cooperating with said operating member to guide the same axially in opposition to said resilient means and subsequently release the same and cause continued rotation thereof under the influence of said resilient means.
  • an electric switch in combination, a stationary member, a movable contact member and an operating member, said operating member having cam parts resiliently held in engagement with cooperating parts on said stationary member and said contact member to impart a number of snap move ments to said contact member in one direction upon movement of said operating member in one direction.
  • a movable cam member having serrated active surfaces, certain of said active surfaces having extensions, a member carrying bearing surfaces arranged to be engaged by certain of said cam surfaces, a. movable contact memcombination,
  • a movable cam member having serrated active surfaces, certain of said active surfaces having extensions, a member carrying bearing surfaces arrangedto be engaged by said active surfaces, a movable contact member arranged to control a pluralit ofv circuit connections, and a spindle tikten ing through all of said members.
  • a movable c am' member a spindle about which" said cam member is arranged to move, a stationary member fixed to said spindle carrying bearing surfaces for said cam member and a movable contact member mounted on said spindle and arranged to be engaged by said cam member to make or break the circuit with a quick snap action.
  • a movable cam member having a serrated cam surface, a spindle about which said cam member is arranged to rotate, a stationary mezbnber earing-surfaces arranged to be engaged y said cam member, and a movable contact member having projections arranged to be engaged bfycertain of said cam surfaces and to be t rown with a quick snap action upon movement of said cam member.

Description

H. W. DENHARD.
ELECTRIC SWITCH.
APPLICATION FILED 001'. 31, 1911.
Patented Oct. 20, 1914.
UNITED STATES PAQTENT OFFICE.
HARRY W. DENHARD, OF SAN FRANCISCO, CALIFORNIA, ASSIGNOR TO THE CUTLER- HAMMER MFG. (30., OF MILWAUKEE, WISCONSIN, A CORPORATION OF WISCONSIN.
I ELECTRIC SWITCH.
Specification of Letters Patent.
Patented Oct. 20, 1914:.
To al'lwhomit may concern:
Be it known that I, HARRY W. DENHARD, a citizen of the United States, residing at San Francisco, in the county of San F rancisco and State of California, have invented new and useful Improvements in Electric Switches, of which the following is a full, clear, concise, and exact description, reference being hadto the accompanying drawin formmg a part of this specification.
y invention relates to electric switches. It has among its objects to provide an 1mproved electric switch.
A further object of my invention is to provide an electric switch adapted to make or break one or more circuits or one or more branches of a single circuit, the switch mechanism being adapted to be operated with a quick snapaction.
purposes of i1 5 switch mechanism. Fi'
view of. a part of t ranged to rotate about a central shaftfi and i Other objects and advantages of my improved construction will hereinafter appear. In the accompanying drawings I' have for ustration .sh'own one form which my invention mayassume in practice. My invention is not however, limited to this form, but may'assume other forms.
"In the views of these drawings :Figure 1 shows a top plan view of this form of vation of the same. Fig. 3 shows a central sectional view through the same.
ating member. Fi
4' actuate a through a suitablecoil Spri a .quick snap movable contact member 5 wit action; the. movable contact member-'5 being: provided'with resilient contact 2 shows aside ele- F g- 4} shows a detail view of a part of the oper' 5 shows a perspective e operating mechanism,- Fig'. 6 shows a'perggective view of the cenand to throw with a quick (bfi plates onshet'sili' and '18, I materiali. nsulated from each other; by suit-j members. ar
contact at suit-able ranged to make or break contacts 6 and 7 mounted upon stationary the base 1.
In a preferred form the operating member 2 is arranged to rotate about the shaft or spindle 3 and is provided with a serrated active surface including a plurality of'radially extending cam surfaces 8 arranged about a central opening 9 and having oppositely sloping sides, the width of which preferably increase toward the periphery of the cam member. In a preferred form two oppositely located cam surfaces 8 have extensions 10 giving them a greater radius than their fellows as shown in Figs. 1 and 4. In a referred form the cam member is forme of a single sheet of metal andthe handle 2 is stamped out of the same sheet of metal from which the. surfaces are formed'.. It is obviousthat this handle may be operated either manually, electrically or by connection to any suitable automatic de: v1ce.-
The cam surfaces 8- are normally held down upon the upper surfaces of rounded bearing surfaces 11 on a stationary member 12 by means of a s ring 4 whose upper end is held upon the s aft as by a pin 13 and Washer 14.. In a preferred form the'member 12 is made up in the form of a diskprovided with .a plurality of spaced steel balls seated upont e upper surface of the same as shown in Fig. steel balls serve to ingf bearin surfaces. I berQIQ isfpreferably provided with a central opening of a type which prevents it from rotatingabout the shaft'B, The disk 12 is in a 1rferredform provided withv asquagre or ot erirregular shaped opening 15 in its center which is tion'or square Jsectionj 16 formed intermediate the. ends ofthe v spind le 3 as shi w'n in j fn apreferred 'foirmfihe inovable contact member 5 ismounted beneath the stationary membervlfi and isarranged to.,be freely rotatable the lower er'id' offthe shaft or spindle 3'. .In a prefer'red con tr ction; the 1 fl1 e be1!. formed of a of "conducti a l a insulation 1 1- em in' c I nd cams provide efficient and last-v The s io y'imeiir) arranged to. house a proje -i gether by suitable screws, rivets or other devices 20 preferably arranged to clamp the conducting parts snugly between the sheets of insulation. If desired I may use more than two conducting plates. The top plate of the contact member 5 is preferably provided with upwardly extending triangular or peaked projections 21, while the contact plate 17 is preferably provided with an enlarged body portion preferably substantially circular and with radially extending integral contacts 22 and 23. In a preferre form these contact members are made resilient and are constructed as shown in Fig. 7 so that their contact surfaces lie in different planes, being provided with a bend intermediate their ends which gives them the desired resiliency and with flat contact arms at their ends in order to enable them to make a good contact. In a like manner the contact member 18 is preferably provided with extensions or contact arms 24: and 25. In a preferred form the contact arms 24 and 25 are arranged substantially at right angles to each other, while the contact arms 22 and 23 are arranged substantially at an angle of sixty degrees from each other. If desired, however, these various contact arms may be so located in the movable contact member as to permit them to be adjusted at any desired position. The contact members 17 and 18 may if desired be stamped from single sheets of metal and the contact arms may be made to extend at any desired angles with respect to each other. In a preferred form the contacts 23 and 25 are slightly shorter than the contact arms 22 and 24.
In a preferred form the contact arms 22 and 24 are arranged to make contact at the contacts 6 which are arranged in an arc of greater radius than the arc of the contacts 7 which are preferably arranged to be engaged by the contact arms 23 and 25. In a preferred form the contacts 6 are shorter than the contacts 7 and are spaced apart from each other by an approximately equal distance; an additional stud 26 being pro vided intermediate certain of the same. In a preferred form the contacts 6 are also ar-- ranged as shown in Fig. 2 being provided with upwardly extending portions 27 having flat contact surfaces 28 arranged sub-- stantially at right angles to the body of the contact members 6 and in a different plane. In a preferred form the contact members 7 are arranged flat upon the surface of the base 1 and are attached to the same by means of suitable bolts or other devices 29. In a preferred form these contact -members are arranged concentrically as shown and are of substantially the same length.
In order to provide a suitable bearingsurface upon the movable contact member 5 carrying the contact arms, I preferably provide a plate 30 corresponding to the upper spindle 3 is preferably housed or seated in a in the plate 31 in.
suitable central openin such a manner as to e ectually prevent the rotation of the shaft. In a preferred form,
the lower end of the shaft is preferably flattened and squared as shown at 33 in Fig. 3 and the plate 31 is provided with a suitable recess arranged to receive the end 33.
When it is desired to operate a switch of. the construction shown in the accompanying drawings, the handle 2 is moved to the right or left by any suitable means. any suitable means may be provided to limit this movement if this is deemed necessary. Assuming that the movement of the handle is to the left or downward as shown in Fig. 1, the cam surfaces 8. are moved to the left. These cam surfaces ride up over'the surfaces of the balls 11 and the extensions 10 ride up over the peaked projections 21. This tends to compress'the spring 4. When the edge of the-shorter cam surface 8 is passed over the crest of the nearest ball 11, the spring 4: tends to throw the cam member downward along the opposite slope of the cam. There is no opposition to this movement by the cam due to its shape, and therefore the movement is decidedly quick, the spring acting directly. However, the extensions 10 extend over the peaked pro- Obviously jections 21. As the shorter cam members 8 f move over the balls 11, the extension 10 moves nearly to the top of the peaked pro-. jections 21. When the cam member is thrown down the opposite slope on the balls 11 the effect of this quick movement is to throw the easily rotatable contact member 5 around on the spindle with a decidedly quick movement in which it is impelled by the spring through the direct engagement with the spring pressed cam member. Thus a quick or positive action is obtained'and a construction is'utilized which may be made up into a very compact form and serve to make or break the circuit orclrcults with a minimum of sparking. I
By my improved construction I am able to provide aswitch which may be arranged to make or break a lurality of circuits or which may be readi y adapted to make or break the branches of a single circuit. My
improved construction is especially adapted to change the circuit connections from series to parallel or vice versa as desired in electric heating devices in order to give three breaks. The movement of the switch in each one of its steps is positive, the handle being moved and the switch then automatically throwing with a quick snap action. As the handle is moved the movable contact member is kept in a fixed relation with the same by the engagement of its projections with the extensions. Thus the contacts may be moved about the spindle by a series of movements of the handle which are distinct from each other, the contact parts in each instance being moved to their new position with a quick snap action. By the arrangement of the stationary contacts and the movable contacts I am able to provide a switch which is very compact and which acts to make or break a circuit with a quick snap action so that there is a minimum of sparking. Further the parts are of a rugged con struction well adapted to withstand long use in service. Further the parts are effectually insulated from each other and are of a type which may be readily and cheaply manufactured.
What I claim as new and desire to secure by Letters Patent is 1. In an electric switch, in combination, a movable contact member, an operating member therefor, a connection between the same permitting a partial movement of said;
operating member independently of said contact member, and means including a stationary cam member for accelerating the movement of said operating member prior to operation of said movable contact memher.
2. In an electric switch, in combination, a stationary member, a movable member, said. members having cam parts resiliently held in engagement to accelerate said movable member upon operation thereof, a movable contact member, and a connection between said contact member and said movable member for imparting movement from the latter to the former but only after acceleration of said latter member.
3: In an electric switch, in combination, a stationary member, a movable contact member, and an operating member having cam parts resiliently held in engagement with cooperating parts .on said stationary member and said contact member.
4. In an electric switch, in combination, a stationary member, a movable contact member, an operating member, said stationary member and said operating member having engaging cam surfaces and said contact member and said. operating member also having engaging cam surfaces, and means resiliently holding said operating member in engagement with both of said other members.
5. In an electric switch, in combination, a rotary contact member, a rotary operating member, cooperating cam faces on said 'members, a non-rotary member, co6perating cam faces on said non-rotary member and said 0 crating member, and resilient means for oldin 'said-operating member in engagement with said non-rotary member and said contact member.
6. In an electric switch, in combination, a non-rotary member, a rotary contact member, a rotary operating member, said nonrotary member and said 0 era-ting member having engaging parts inc uding a peaked cam member and said contact member and said operating member also having engaging parts including a peaked cam'member, and means resiliently holding said operating member in engagement with said non- {)otary member and also said contact mem- 7. In an electric switch, in combination, a rotary contact member, a rotary operating member, said members having engaging parts permitting a combined rotary and axial movement of said operating member in one direction independently ofsaid con-- tact member but causing'operation of said contact member upon a reverse axial move-' ment of said operating member, and means including a non-rotary cam for causing said axial movements of said operating member when rotated and for accelerating said reverse axial movement of said operating member. I
8. In an electric switch, in a rotary contact member, a rotary operating member, said members having engaging parts permitting a combined rotary and axial movement of said operating member independently of said contact member but insuring operation of said contact member with said operating member upon a reverse axial and continued rotar movement of the later, resilient means biasing said 0 crating member in said reverse axial direction, and a stationary cam cooperating with said operating member to guide the same axially in opposition to said resilient means and subsequently release the same and cause continued rotation thereof under the influence of said resilient means. a
9. In an electric switch, in combination, a stationary member, a movable contact member and an operating member, said operating member having cam parts resiliently held in engagement with cooperating parts on said stationary member and said contact member to impart a number of snap move ments to said contact member in one direction upon movement of said operating member in one direction.
10. In an electric switch, a movable cam member having serrated active surfaces, certain of said active surfaces having extensions, a member carrying bearing surfaces arranged to be engaged by certain of said cam surfaces, a. movable contact memcombination,
berarranged to be actuated bythe extensions on said cam surfaces and a spindle extending through all ofsaid members.
11. In an electric switch, a movable cam member having serrated active surfaces, certain of said active surfaces having extensions, a member carrying bearing surfaces arrangedto be engaged by said active surfaces, a movable contact member arranged to control a pluralit ofv circuit connections, and a spindle tikten ing through all of said members.
12. In an electric switch, a movable c am' member, a spindle about which" said cam member is arranged to move, a stationary member fixed to said spindle carrying bearing surfaces for said cam member and a movable contact member mounted on said spindle and arranged to be engaged by said cam member to make or break the circuit with a quick snap action.
.mounted on said spindle and havin .14. In an electric switch, a movable cam member having a serrated cam surface, a spindle about which said cam member is arranged to rotate, a stationary mezbnber earing-surfaces arranged to be engaged y said cam member, and a movable contact member having projections arranged to be engaged bfycertain of said cam surfaces and to be t rown with a quick snap action upon movement of said cam member.
15. I1? an electric switch, a movable cam I member having a serrated active surface,
\certain of said active surfaces having extensions, a member carrying bearing surfaces arranged to be engaged by said active surfaces, a movable contact member arranged to control a plurality of circuit connections, a spindle. extending through all of said members, and resilient means. arranged to throw said movable contact member with a quick snap action when said cam member is actuated.
In witness whereof, I have hereunto subscribed my name in thepresence of two witnesses.
HARRY w. DENHARD.
Witnesses:
H. ROCKWELL, GEO.-D. Jonas.
US65781411A 1911-10-31 1911-10-31 Electric switch. Expired - Lifetime US1114680A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2796487A (en) * 1955-02-09 1957-06-18 Allen Bradley Co Snap action mechanism
US4948052A (en) * 1989-04-10 1990-08-14 Hunter Edwin J Reversible gear oscillating sprinkler with cam controlled shift retainer

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2796487A (en) * 1955-02-09 1957-06-18 Allen Bradley Co Snap action mechanism
US4948052A (en) * 1989-04-10 1990-08-14 Hunter Edwin J Reversible gear oscillating sprinkler with cam controlled shift retainer

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