US 2626335 A
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Description (OCR text may contain errors)
Jan. 20, 1953 c, LANDIN 2,626,335
ELECTRIC SWITCH Filed Oct. 18, 1950 A V W 7r nun w if 25 INVENTOR CARL ARTHUR LAND/N A T TORNEYS Patented Jan. 20,1953
signer to The Hart Manufacturing Company, Hartford, Comm, a corporation of Connecticut Application October 18, 1959, Serial No. 190,850
1 Claim. 1
This invention relates to electric switches and more particularly to indexing means for the switch lever of relatively small switches of the type frequently used to regulate the circuits of various household appliances, motors, and the like.
It is an object of the invention to provide an electric switch comprising components which may be inexpensively manufactured and assembled to reduce the cost thereof and particularly the indexing means by which the switch lever is resiliently biased to its several predetermined or selective positions and is also releasably maintained in each selected position.
It is another object of the invention to provide in an electric switch of this nature indexing means which are simple and foolproof and which are maintained in operative position within the switch assembly by the biasing force of the indexing means.
Other objects will be in part obvious and in part pointed out more in detail hereinafter.
The invention accordingly consists in the features of construction, combination of elements and arangement of parts which will be exemplified in-the construction hereafter set forth and the scope of the application of which will be indicated in the appended claim.
In the drawings:
Fig. 1 is a perspective view of an exemplary switch embodying the present invention;
Fig. 2 is a sectional view of the switch illustrated in Fig. 1 but shown on larger scale and the switch elements being positioned in off position;
Fig. 3 is a view similar to Fig. 2 but showing the switch elements in on position;
Fig. 4 is an exploded perspective view of the switch illustrated in Figs. 1 through 3, the components of the switch shown in the order of their assembly, and
Fig. 5 is a cross-sectional view taken along the line 55 of Fig. 2.
Referring to the drawings, the switch embodying the present invention is denoted generally by reference numeral and it includes a generally rectilinear casing I2 consisting of a front wall I8, vertical longitudinal walls 34, and horizontal longitudinal walls 26. The interior surfaces of the walls referred to define an internal cavity It in which are mounted the movable parts of the switch. If desired, the entire casing i2 may be molded in one piece of suitable non-conductive material such as. for example, a moldable synthetic resin.
Adjacent the back of the switch, at the interior corners formed by the juncture of longitudinal walls 34 with the horizontal walls 26 the walls 34 are longitudinally grooved as shown at 53 so as to form a slot for receiving rectangular terminal plates 38 and 52 which may be inserted endwise and slid inwardly therein to their full length. The terminal plates 48 and 52 may be provided with tapped holes 54 for the reception of a connecting screw (not shown) for holding a connecting wire. The top and bottom walls 26 are cut away as at 28 to expose the tapped openings 54 in the terminal plates 48 and 52 so that suitable connections can be made thereto. The edges of the terminal plates as and 52 may be provided with struck-up portions 49 and El, respectively, to assist in retaining the plates in assembled (inserted) position by resiliently engaging the side edges 'of the grooves.
The contact plate 52 has an upwardly bent lug 55 on which is supported a fixed contact 58. The contact plate 43 has a downwardly depending resilient and flexible switch arm '64 supporting the movable contact 46 of the switch. The switch is opened and closed by flexing the arm 44 to separate or bring together the contacts 58 and 50.
For operating the switch arm 44 and hence the movable contact 46, there is provided a switch lever 24 which is pivotally supported on a pin 3i; extending between openings 32 in the side walls 35 of the casing 12. The handle portion of switch lever 26 projects outwardly through an opening 22 in the front wall I3 which may have suitable legends 20 such as on and ofi for indicating the several positions of the switch.
The nose 42 of the switch lever 24 is in the shape of a cam and engages against a .bend in the flexible switch arm 44 to earn the switch arm i l and hence the movable contact it out of engagement with the stationary contact 53 when the switch lever 24 is pivoted to off position. Conversely, when the switch lever is pivoted to on position, the shape of the nose 42 is such as to permit return movement of the switch arm 44 to re-engage the movable contact 46 with the fixed contact 50.
In order that the switch lever 24 may be biased into its several positions and releasably maintained in each selected position by indexing means constructed and arranged in accordance with the invention, the same is provided with a plurality of arcuately spaced notches 38 and 40 which are arranged to correspond respectively to the off and on positions of the switch lever 24.
In accordance with the invention, the periphery of the switch lever 24, adjacent the arcuately spaced notches 38 and 40, is engaged by a roller 16 mounted on a pin 14 which is rotatably received in the bifurcated end 12 of a spring 66, the spring 66 being of a simplified design and self-biased into operating position so that no additional fastening means is required, thus greatly facilitating the assembly of the switch, and, at the same time, causing the indexing means to function in an improved manner. The spring 66 essentially is generally V-shaped and comprises an arm 61 extending inwardly and upwardly at an acute angle from one end of a base 69, the apex of the spring preferably being rounded as indicated at 68. The width of the base 69 is such that it may be inserted endwise along the upper surface of the bottom wall 26 and can be slid endwise into seated position on the seat '10 between the side walls 24 in advance of the grooves 53. In the preferred embodiment of the invention, the base 69 is made slightly convex relative to the seat l8 so as to improve the resiliency of the spring.
As a result of the design of the spring 66 and the cooperating seat 10 of the casing and terminal plate 52, it has been found in accordance with the invention that the spring 66 may be securely locked in place without the use of any fastening devices, merely by sliding the base of spring 66 inwardly along the inner surface of the bottom wall 26 to position the spring 66 in seated position with its base 69 seated on the surface 10 between the side walls 24 and then inserting the terminal plate 52. As best shown in Figs. 2 and 3, the lug 53 on the front of terminal plate 52 bears against the apex 68 of the spring 66 and this pressure, in combination with the seating of the spring base 69 on the surface 10 and the engagement of the roller 16 with the periphery of the switch lever 24, acts to securely wedge the spring 66 into seated position from which it cannot be displaced by any of the operating pressures encountered during the use and functioning of the switch.
As will be apparent, the engagement of the roller 16 with the periphery of the switch lever 24 under the influence of spring 66 will bias the switch lever 24 into either one of its selected positions, i. e., with the roller 16 engaged in the notch 38 or the notch 40. When the switch lever 24 is pivoted from either position, the roller 16 first has to ride up on the land between the notches 38 and 49 thus increasing the load on the spring 66 and then when the high point is passed, the spring and roller assist in moving the switch lever to selected position with a snap action.
It is an advantage of the present invention that the design of the spring 66 and the manner in which it is seated in the casing is such that the force exerted on spring 66 through roller 16 when the switch lever 24 is pivoted between selected positions will not cause the spring 66 to tip or pivot out of seated position even though the force is angularly directed with respect to the base of the spring 68. Any tendency of the spring 66 to become displaced from its operative position as a result of this angularly directed force is entirely and effectively prevented. This arrangement is also found to be effective for avoiding any tendency of the spring to jump from seated position when the switch is operated in rapid fashion.
Inasmuch as the spring 66 is effectively positioned in operative position within the cavity 14 without the need for any fastening devices, the number of parts required in the switch is materially reduced and the assembly of the switch is greatly simplified. In order to assemble the switch, it is necessary merely to slide in the spring 66 with the roller 16 in proper position thereon, insert the switch lever 24 and pin 30 and then the spring 66 is forced into seated position by the lug on the terminal plate 52. The terminal plate 48 with its depending switch arm 44 may then be similarly inserted and the inner end of the housing can then be closed by an I-shaped back plate 56 of suitable insulating material which is received in the depression [6 at the rear of the casing and engages against the outer edges of the terminal plates 48 and 52. The insulating holding plate 56 in turn is locked in position by means of a retaining clip 58 having side arms 62 received in the grooves 35 of the side walls and having end holes 64 so that the same may be snapped over the ends of the pin 35 supporting the switch lever 24. If desired, the retaining clip 58 may also be provided with outwardly bowed snap fingers 60 for holding the switch in a suitable opening in an appliance wall or the like.
It thus will be seen that there has been provided in accordance with the invention, a toggle switch which is foolproof in operation and yet which contains a minimum of parts and can be easily fabricated and assembled with a minimum of difficulty and expense.
While the invention has been described, for simplicity and clarity of presentation, in connection with a switch having only two operating positions and a single pair of contacts, it will be readily appreciated that the invention will apply equally well to a switch having additional operating positions and additional contacts without departing from the scope thereof.
As many changes could be made in the above construction and many apparently widely different embodiments of this invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.
It is also to be understood that the language used in the following claim is intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.
I claim as my invention:
A switch comprising a casing having a front Wall and longitudinal side Walls defining an interior cavity extending inwardly from one end thereof, relatively movable contacts and supporting members therefor mounted within said cavity, one of said supporting members cooperating with said front wall to form a seat therebetween on the interior surface of one of the longitudinal walls, a switch actuating lever pivotally supported by said casing and having one end extending into said cavity and provided with a plurality of notches in the edge of said end of said lever arcuately spaced in accordance with the several positions of said. lever, and resilient detent means cooperating with said lever releasably to retain said lever in said several positions, said detent means comprising a V-shaped spring having one leg resting within the seat with its apex engaging with said one contact supporting member and having the other leg extending at an angle to the seat to engage said lever to resiliently retain said one leg within said seat,
CARL ARTHUR LANDIN.
REFERENCES CITED The following references are of record in the 10 file of this patent:
UNITED STATES PATENTS Name Date Rohne May 20, 1919 Number