US2139561A - Switch mechanism - Google Patents

Description

Dec. 6, 1938. c. M. PETERSEN SWITCH MECHANISM Filed June 23, 1954 2 Sheets-Sheet 1 INVENTOR.

Dec. 6, 1938. c. M. PETERSEN SWITCH MECHANISM Filed June 23, 1934 2 Sheets-Sheet 2 INVENTOR. M M. PM

ATTORNEY Patented Dec. 6, 1938 PATENT OFFICE swrrcn Mscmmsm Carl M. Petersen, Morrlsville, Pa; Stella W. Petersen executrix of said Carl M. Petersen,

deceased Application June 23, 1934, Serial No. 732,006

5 Claims. (01. 200-17) My invention relates to switches and particularly to snap acting switches of the type in which gradual movement of a member causes a contact to be moved rapidly from one position to another.

Devices of this character are widely used and although they differ considerably in form and construction, in general, they fall into two classes, namely: rotary switches and toggle operated switches. Rotary switches ordinarily are made up of a comparatively large number of parts and are therefore expensive to manufacture and complicated to construct and assemble. Although toggle operated switches are much simpler in construction and less expensive to manufacture they only provide for two positions or circuit arrangements such as on and 0115" or high" and low. This is due primarily to the fact that it has been usual practice to attain the desired snap action by employing members extending in opposite directions from their respective supports between which a spring extends to cause movement of one member beyond a center line to effect rapid movement of the other member from one position to another. These members cannot be positioned so as to remain exactly on the center line with the spring held under tension or compression and therefore they are always carried over to one side or the other of the center line to either extreme position.

In accordance with my invention these disadvantages in constructions of the prior art are overcome and a toggle operated switch provided which may be moved to each of more than two positions in which it tends to remain. Switches embodying my invention may also be made from a limited number of parts of simple construction capable of being easily and economically manuiactured and assembled. Certain features of my invention also lend themselves to the manufacture of single acting toggle operated switches of the type now in common use.

One of the objects of my invention is to reduce the cost and simplify the mechanism employed in the construction of switches of the to accompanying figures of the drawings illustrating preferred embodiments thereof.

In the drawings:

Fig. 1 is a rear elevation of a preferred form of the switch embodying my invention with the cir- 5 cult controlling means removed.

Fig. 2 is a central vertical section through the switch. a

Fig. 3 is an enlarged fragmentary view, partly in section, showing the manner in which certain 10 of the switch elements are moved.

Fig. 4 is a front elevation of the contact carrying portion of the switch.

Fig. 5 is a front elevation of the switch with the parts moved from their central position.

Figs. 6, 7 and 8 are fragmentary views illustrating alternative forms of bearings or supports for elements of the switch.

In that form of my invention chosen for illustration in Figs. 1 tub of the drawings the device 20 comprises a frame in the form of a U-shaped stamping having a bottom 2 and sides 4. The sides are provided with projecting ears 6 for attachment of the switchand frame to a support 8 and with upwardly extending legs ID to which is secured a contact carrying member such as the plate l2 formed of insulating material. A small plate or metal stamping ll extends across the U-shaped frame beneath the contact carrying plate l2 and is supported at its ends upon the sides 4 of the frame.

The bottom 2 of the frame and the plate H are provided with aligned openings ltof the form shown in Figs. 1, 3 and 5, the bases of which openings provide a support for a contact operating member it. The member Ills in the form of a U-shaped stamping having outwardly projecting bearing members or fingers 20 entering the openings IS in the plate It and the bottom 2 of the frame. The form of these bearing members 40 as shown in Fig. 1 is such that the contact operating member rocks on one or the other of the lateral edges of the respective bearing members at the opposite ends of the base of the openings 16. The bearing members, if desired, may be turned downwardly at 22 and 24 to rest in recesses 26 at the ends of the bases of the openings It, thus preventing lateral displacement of the member i8 when it is moved from one position to another. The portions 22 and 24 may also be notched to prevent vertical displacement of the member I! and to provide knife edges permitting easy movement of the contact operating member.

The portion 28 of the contact operating member l8 extends away from the support for said 2 2,1so,so1

member and is provided withan upwardly extending arm 30 for actuating the movable contact of the switch.

As shown in Fig. 3 movement of the contact operating member II to the right from the central position shown in full line, for actuating the switch causes said member to rock about the downwardly turned edges 22 of the bearing members 20 whereas movement of the member tov the left causes it to rock about the downwardly turned edges 24 of the bearing members. In the central position of said member both the edges 22 and 24 at the opposite sides of the bearing members 20 rest in the recesses 26 at the opposite ends of the bases of the openings II. This cbnstruction of the contact operating member and of the support therefor provides three positions to which the member may be moved. Movement of the member to one position takes place about one bearing, say 22, movementof the member to another position takes place about another bearing, say 24, while the member when in its central position bears against both said bearings.

In order to actuate the contact operating member in the manner above described I prbvide actuating means such as the rock lever or handle 42 which preferably is formed to be supported in an opening 48 and to rock about two diiferent pivot portions in a manner somewhat similar to that described above for the movement of the contact operating member. The handle 42 can conveniently be made of a stamping, the lower end 44 of which is offset to provide a surface 4! that rests against the base of the opening 48 in the bottom 2 of the frame. The actuating means for the switch when in its central position is urged against the base of the opening 4| by the switch spring 50. When moved to either side from its central position to actuate the switch it rocks about either the right hand edge I2 (Figs. 1, 3

and 5) or the left band edge 54 of the surface 46 as bearings. If desired, the edges 52 and 54 may be turned downwardly similarly to the edges 22 and 24 of the contact actuating member it although this is not essential to the operation of the switch.

The handle or actuating means 42 extends from its pivot portions in the opposite direction from that in which the member it extends and is provided with an element 56 projecting through an opening or slot 58 in the base 2 of the frame. The switch spring is connected to the element 56 and to the portion 28 of the contact operating member, or to an inwardly extending portion of the arm 30, as shown. With this arrangement of the parts described gradual movement of the actuating means from one position to another causes the contact operating member and the movable switch contact to be rapidly moved from one position to another.

However, in contrast with devices of the prior art, the construction shown embodies means serving to enable the switch members to be retained in intermediate positions between the extreme positions to which they may be moved. Thus the construction includes a handle or actuating means movable to any one of three alternative positions to obtain diflerent circuit arrangements or conditions. In the central position of the actuating lever the lever and the contact operating member are both balanced in an intermediate position. As shown in Figs. 1 to 5 the lever or handle is urged toward its central position by the action of spring SI cooperating with the surface 43 on the lower end of the handle. 4 Similarly the contact operating member is balanced on its pivot portions 22 and 24. When the actuating means or rock lever 42 is moved to the right in a counter-clockwise direction against the action of spring 50 from the position of Fig. l to that shown in dotted lines at the right of Pig. 3 it rocks about its pivot portion l2 rrying the end of the spring beyond a line passing through pivot portion 22 of the contact operating member and the point of connection of the spring to said member. The contact operating thereupon snaps over from its central position to the right moving in a clockwise direction about its support under the action of the spring. The point of connection of the spring to the contact member is positioned so as to be carried by this movement beyond a line passing through the pivot portions 22 and 52 of the contact operating member and rock lever respectively so that the spring thereafter acts on the handle to move the same further in the direction in which it was being moved and to hold both the handle and the contact operating member in their extreme lateral position. In a similar way movement of the handle or rock lever 42 back from its lateral position toward the central position carries the spring pasta point at which the direction in which the spring urges the handle and the contact operating member is reversed bringing them to a stop in the central position in which they tend to remain until moved to another position. Movement of the handle 42 to the left of the central position acts in a like manner to cause the handle and contact operating member to move to the left, in opposite directions with respect to their supports, so as to assume a third position in which they are held by the action of the spring.

In moving from the central to either lateral position the actuating means and the contact operating member move bodily with respect to one pivot portion about the other pivot portion, both members serving to carry the spring from one position to-another in which it assumes a substantially parallel position, as shown in Fig. 3. Due to the novel type of bearing and support for the actuating means and the contact operating member each has two independent oscillating movements through intersecting arcs or curved lines in contrast with the usual movement about a fixed axis in present types of toggle operated switches.

Operation of the actuating mechanism for the switch as described above serves to cause the switch contact to be relatively moved to control a plurality of circuits as desired. In the construction illustrated the contact operating member is provided with an upwardly extending arm 30 loosely engaging an insulating member 32 to which a movable contact 34 of the switch is secured. The element 32 preferably is rotatable upon a mounting 36 extending downwardly from contact carrying plate i2. Movement of the contact operating member I 8 from one position to another causes the element 32 to be rotated to actuate the movable contact 34 as desired. However, since the contact operating member is moved to different positions about two different bearings and further since neither of these bearings is in alignment with the axis of rotation of the element 32 by which the movable contacts are carried, I provide means for compensating for the difference in location of the bearing about which the contact operating member and the element 32 are moved. This means as shown, is in the form of a slot 38 in a projecting portion 40 of the element 32 into which the arm 30 of the contact operating member extends. With this construction the contact operating member may be actuated as desired causing the element carrying the movable contact of the switch to be rotated on the mounting 36 from one position to another.

The form of the contacts employed in switches embodying my invention may of course be varied considerably but for simplicity in construction I prefer to mount all of the contacts on an insu lating member such as the plate I2. The actuating mechanism then maybe made and assembled independently of the contacts and the contacts may be made, assembled and tested and if necessary adjustments thereof may be made before the plate and contacts are secured in position on the frame.

As shown in Figs. 2 and 4 the plate I2 carries both the fixed and movable contacts for the switch on that side thereof facing the switch actuating mechanism. Binding posts or screws for the attachment of conductors to the switch extend from the opposite side of the plate I2 so as.

ried by the insulating member 32 to provide a double pole, double break switch. Each contact comprises a common segment 64 from which extend radial contact arms 66. The contacts are preferably formed in duplicate with one element located on the upper face and the other on the lower face of the insulating member 32 to insure proper engagement of the movable contacts with the fixed contacts.

The fixed contacts 68 are each formed as'part of a member I0 which is threaded to receive a screw I2 for securing a conductor to the contact. These members are formed to be readily inserted into opening 14 in the plate l2 with that portion thereof which constitutes the fixed contact located in spaced relation with the lower face of the plate I2 and with the extended portion for receiving the screw I2 located on the upper face of the insulating plate. he extended portion 16 extends outwardly beyond the side of the opening I4 to prevent downward displacement of the member I0 and the contact 68 and extends inwardly and downwardly at I8 providing a projection which is expanded on the underside of the plate I2 to prevent upward displacement of the member I0. With this construction the contacts and binding posts may be readily manufactured by simple stamping operations and are capable of easy attachment to the plate I2.

When the fixed and movable contacts have been secured to plate I2 they may be tested and adjusted before attaching the plate to the frame carrying the actuating mechanism. The parts are assembled to complete the switch by inserting arm 30 of the contact operating member in the slot 38 of the portion 40 of member 32. Openings in the plate I2 are then brought into registry with projections 82 on the legs I0 of the frame and the projections are expanded to prevent removal of the plate. In this Way the contacts and the operating mechanism may be easily formed and assembled without great expense or difiiculty.

In the operation of snap switches it sometimes happens that the contacts stick, especially if the switch is not operated frequently. In order to overcome this difiiculty I provide the operating handle with a projecting element 84 positioned to engage an extended portion 86 of the bearing 20 as shown in Fig. 5 to positively initiate movement of the contact operating member independently of the spring 50.

The arrangement of the element 84 and the projecting portion 86 is such that after the initial movement of the contact operating member and movablecontacts has been made the spring causes the contact operating member to be moved rapid- 1y from one position to another so that the movable contact is moved quickly, away from the stationary contact which it engages.

In the construction shown in Figs. 1 to 5 inclusive of the drawings both the contact operating member and the actuating means are formed with two definite pivot portions. However, 'this is not essential in order to obtain the advantages of a three position toggle operated switch in accordance with my invention.

As shown in Fig. 6 the handle or actuating means may be provided with an element I04 which is substantially circular in cross-section except for the flattened portion I06 thereof. This element extends through the opening I08 in the frame and when in the central position the flattened portion I 06 bears against the flat surface at the base of the opening I08. Upon movement of the actuating means to either side from the central position the axis of the element I04 will move in a line perpendicular to the base of the opening I08 about one of the edges of the fiattened portion I06. The action of the actuating means in this construction is substantially the same as that shown in the construction in Fig, 5 although the edge of the flattened portion I06 continuously moves with respect to the base of the opening I08 during movement of the actuating means from one position to another.

Similarly as shown in Fig. 7 the bearings for either the contact operating member or the actuating means may be in the form of an angular surface II2 bearing against an angular surface H4 in the base of an opening H6 in the frame. In this construction the actuating means when moved to either side from the central position bears against two points, namely, I I8 and I20 each of which move with respect to the angular surface II4 of the opening IE6. The oscillation of the free end of the actuating means or contact operating member having this type of bearings describes a parabolic or irregular movement about the bearings which are not stationary with respect to the surface they engage. Operation of the remaining elements of the construction will, however, be substantially the same as that described in connection with Figs. 1 to 5.

In Fig. 8 the bearing is shown as having'a fixed axis of rotation I22 but is provided with a surface I24 cooperating with a spring I26 to retain the actuating means 42 in a central or other intermediate position between the .limits of its movement.

While I have illustrated and described various alternative movements of my invention it will be apparent that the form and construction of the elements employed may be varied considerably and the mechanism may be used in conjunction with different forms and types of contact elements and circuit arrangements without departing from the spirit and scope of my invention.

It should, therefore, be understood that the construction shown and described are illustrative scope thereof.

ill

mg a supporting mernher to pivotaliy support the said fingers which adapted to reel: on said support each about its a finger with opposite pivot portions for-pivotally supporting the lever in said supporting member to reel: thereon about said portions, said operating lever having means extending toward the fingers said movable element, and resilient means connecting said movable element and the extending means of the operating lever to hold the fingers of said element and the finger oi the operating lever to their respective suppo'ts and to transmit movement of the oper-- lever to the movable element when the said lever is actuated.

2. In switch mechanism: the combination with circuit controlling means including a movable element l aving a pair of oppositely directed fingers, each finger having opposite pivot portions; of means to rock said movable clement comprising a supporting member to pivotally support the sen. fingers which are adapted to rock on said support each about its respective pivot portions, an operating lever having a finger with opposite pivot portions for pivotally supporting the lever in said supporting member to rock thereon about said portions, said operating lever having a further finger extending toward the fingers of said movable element, and resilient means connecting said movable element and the second-named of the operating lever to hold the fingers or" said element and the firstmamed finger of the operating lever to their respective supports and to transmit angular movement of the operating lever to the movable element when the said lever is actuated.

In switch mechanism: the combination with circu t controlling means including a movable element having a pair of fingers, each finger having opposite pivot portions; of means to rock said movable element comprising a supporting member to pivot-ally support the said fingers which are adapted to rock on said support each about its respective pivot portions, an operating lever having a finger with opposite pivot portions for pivotally supporting the lever in said supporting member to rock thereon about said portions, said operating lever having means extending toward the fingers of said movable element, and resilient means connecting said movaisacoi the extending means of the smit angular the movable tuated, together further om the lever to initiate movement of the movable element independently of said resilient means.

l. In switch mechanism: the cornlination with circuit controlling means including a movable element having a pair of oppositely directed fingers, each finger having opposite pivot portions; of means to rocir said movable element comprising a supporting member to pivotallv support the said fingers which are adapted to rock on said support each about its respective pivot portions, an operating lever having finger with opposite pivot portions for pivotally supporting the lever in said supporting member to rock thereon about said portions, said operating lever having a further finger extending toward the fingers of said movable element, and resilient means connecting said movable element and the second-named finger of the operating lever to hold the finger of said element and the finger of the operating lever to their respective-supports and to angular movement or" the operating lever to the movable element when the said lever is actuated, together with a third finger projecting inwardly from the lever to engage directly the said movable element during the initial movements of said lever from an intermediate position 5. In switch mechanism: the combination with circuit controlling means including a U-shapc movable element having oppositely directed fingers, each finger having opposite pivot portions; of means to rock said movable element comprising a supporting frame apertured to receive the respective fingers to pivotally support the said fingers which are adapted to rock in said apertures each about its respective pivot portions, an operating lever having a finger with opposite piv- 0t portions and extending into a further aperture of said frame to pivotally support the lever therein to rock thereon about said pivot portions, said operating lever having a further finger extending toward the fingers of said movable element, and a spring connecting said movable element and the second-named finger of the operating lever to and respective element wh -n hold the fingers of said movable element and the first-named finger of the operating lever to their respective supports and to transmit angularmovement of the operating lever to the movable element when the said lever is actuated.

CARL M. PETERSEN.

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