US3457802A - Cam actuated switch structure - Google Patents

Description

July 29, 1969 Filed Oct. 12, 1967 .1. L. GLANCY 3,457,802

CAM ACTUATED SWITCH STRUCTURE 2 Sheets-Sheet 1 zzvvmae.

J JERRY L. Guwcv woizwuzzuwa m l 22mg:

July 29, 1969 J. L. GLANCY 3,457,802

CAM ACTUATED SWITCH STRUCTURE Filed Oct. 12, 1967 2 Sheets-Sheet 2 Fig. 6. Fig.7.

INVHVYUR JERRY L. Gumcv United States Patent US. Cl. 74--568 2 Claims ABSTRACT OF THE DISCLOSURE A cam actuated, multiple switch structure in which the switch elements are actuated by cams rotated by gears meshing with a central driving gear, moved manually or automatically, with the orientation of the cam-gears with the central driving gear being alterable so that switch assemblies having various sequences of switch operation can be assembled from the same basic parts or components.

BACKGROUND OF THE INVENTION Field of the invention The invention may be categorized as in the field of camactuated, sequentially operable electrical switches.

Description of the prior art Many modern electrical appliances, such as automatic washers and dryers, incorporate as part of their control systems multiple switch assemblies which are manually operated to alter the operation of the appliance in accord with a desired sequence of operation. Since the control sequence, or the featured group of possible operational sequences, in such appliances varies widely from manufacturer to manufacturer of the appliances, supplying these switch assemblies to these appliance manuafcturers has heretofore necessitated manufacture and stocking of a Wide range of switch assemblies which, while similar, incorporate differing switch parts and require different assembly techniques and testing procedures. The economic toll which is thus levied where the switch manufacturer wishes to supply a broad range of appliance manufacturers can be substantial.

SUMMARY The present invention provides a multiple switch structure of the type in which a rotary motion of the control knob or shaft produces a sequential actuation and deactuation of the individual switch components, the switching sequence or program of the switch components being determined by the relative orientation of driving and driven gear elements at assembly of the complete switch structure. A flexibility of manufacture is thus achieved, permitting requirements for switch assemblies with differing switching sequences to be filled without requiring manufacture or stocking of differing switch parts or components.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top plan view of the switch structure of the present invention with portions removed in order to clearly show, particularly, the contact structure.

FIG. 2 is a side view of the control shaft carrying the detent cam and the driving gear.

FIG. 3 is a top plan view similar to FIG. 1 but showing the portions omitted from FIG. 1 in place in the switch assembly.

FIG. 4 is a top plan view of one of the driven gears and the attached cam.

FIG. 5 is a side sectional view taken generally along the line 5-5 of FIG. 4.

3,457,802 Patented July 29, 1969 FIG. 6 is a fragmentary view illustrating co-operation of one of the cams with its switch actuation-controlling members.

FIG. 7 is a fragmentary view similar to FIG. 6 but illustrating the coaction of the other of the cams with its switch actuation-controlling members.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring initially to FIG. 1, the embodiment of the present invention includes a rectangular switch housing, indicated generally at 10, having a base surface 11. Extending upwardly from the base are posts 12 and 14 and a. circular boss which defines a socket or aperture 13. Extending through slots in the base are fixed contact terminal blades 16 and 17 each of these carrying fixed electrical contacts 16a and 17a, respectively, the blades extending through the base 11 to provide electrical terminal connections for the contacts. The base also is provided with slots which can accommodate additional terminal blades for modification of the switch structure to a double-throw type.

Adjacent one margin a terminal bracket 18 is appropriately accommodated in slots formed in the base (the bracket 18 extending through the base to provide a terminal connection), the bracket 18 having rigidly supported thereon the extending, resilient movable contact carrying blades 19 and 21. At their free ends the blades 19 and 21 are provided with movable contacts 19a and 21a respectively. Intermediate their length the blades are offset and notched, as indicated at 1912 and 21b, providing cam engaging surfaces, the operation of which will be subsequently described. A terminal element 22, carried by the base 11, similarly mounts a resilient switch actuation-controlling member or blade 23 having cam-engaging, notched portion 23b and carrying a movable contact 23a. A contact terminal assembly 24 is also carried by the base and presents fixed contacts 26 and 27 to the movable contacts 23a and 21a, respectively. The terminal element 28 supports the resilient, movable contact carrying blade 29 which has a cam engaging surface 2% and, at its free end, carries the movable contact 29a. The movable contact 29a co-operates with the fixed contact 17a.

Referring now to FIG. 2, the driving gear structure includes a driving shaft 31, which may have a flattened portion facilitating insertion of a knob on the shaft, which carries the driving gear 32 and is provided with a stepped end portion 33 which is adapted to be received in the aperture 13 of FIG. 1. Just above the driving gear 32, the shaft 31 carries a detent cam 34 whose facial contour is shown in FIG. 3 and whose operation will be subsequently described.

The driven gear and cam element 36 accommodated on the post 14 of FIG. 1 are shown in detail in FIGS. 4, 5 and 6. The gear and cam element is counterbored as indicated at 37 to accommodate the post 14 and is provided with sidewardly extending lobes 38 and 39 (FIG. 4) which, as may best be seen in FIG. 6, co-operate with the offset portions 19b and 21b of the contact carrying blades 19 and 21 respectively. The driven gear and cam element 36 is provided with gear teeth 41 which are adapted to mesh with the driving gear teeth 32, as will be evident from FIG. 3. The upper face of the driven gear and cam element is provided with a series of index markings 42 which aid in orientation of the driven gear with the driving gear as will subsequently be described.

Similarly, as will be evident from FIG. 7, a driven gear and cam element 51, has gear teeth 52, adapted for meshing with the driving gear teeth 32. The element 51 further carries a single lobed cam 53 which is adapted to cooperate with the offset portions of contact carrying blades 23 and 29 which are shown fragmentarily in FIG.

7. The aperture 54 in the driven gear and cam element 51 is adapted to accommodate the post 12, shown in FIG. 1. The front face of the element 51 is provided with a series of index markings (identified at 56 in FIG. 3) which are similar to the index markings 42 of the driven gear and cam element 36 previously described with reference to FIGS. 4, 5 and 6. It will be understood that while gear and cam element 36 is illustrated as having two diametrically opposite cam lobes 38 and 39, and gear and cam element 51 is illustrated as having a single carn lobe 53, other forms of cams might be utilized to provide difiering switch operating sequences.

FIG. 3 illustrates the assembled switch structure, that is, the structure having the two driven gear and cam elements in place on the shafts 12 and 14 and with the driving gear assembly in place in the accommodating socket 13. Overlying the driving gear and the meshing driven gear and cam element faces is a plate 61 which is provided with elongated apertures 62 and 63 which permit viewing of a portion of the index markings on the driven gear and cam element faces. Extending from opposite corners of the housing sidewalls are spring blades 66 and 67 which cooperate with the lobes 34a of the detent cam 34 to establish detent positions for the driving gear separated at 90 intervals as the shaft is rotated. The housing may be further provided with an overlying plate 68 (a portion only of which is shown in FIG. 3) which carries a depending abutment 69 which co-operates with a stop-cam 71 which may be carried by the shaft 31. When the stop is utilized on the shaft 31, it will be understood that the abutment 69 functions as a stop, permitting rotation of the shaft 31 clockwise only from the shaft position of FIG. 3.

In operation, upon assembly of the switch the driven gear and cam elements may be oriented with respect to the driving gear in any prescribed fashion, the prescription directing that some one of the index markings (letters or numerals) on the face of the gear and cam element 36 be centered in the aperture 63. Additionally, some one of the index markings on the gear and cam element 51 may be centered in the aperture 62 to thereby provide any desired relative positioning of the cam lobes moved by the driven gears and, hence determining the sequence of operation of the switching members as the driving shaft 31 is rotated, the desired relationship being obtained merely by an indication of which numeral is to appear centered in each of the two apertures 62 and 63 upon assembly. The orientation of the driven gears with respect to the driving gear illustrated in FIG. 3 is such that the 0 index marking on the gear assembly 36 is centered in the window 63 and the 6 index marking on the gear element 51 is centered in the aperture 62. This places the cams in their positions of FIGS. 6 and 7, however, as mentioned above, other initial positions of the cams can be established by initially positioning the driven gears relative to each other so that numerals other than 0 and 6 are visible and centered in the apertures 62 and 63 as the switch is assembled. While the detent cam" 34 is illustrated as providing 90 intervals, the detent cam might be arranged so that 45 or other detent intervals would be provided. It will also be understood that both the number of index markings on each gear face and the number of teeth on the driving and driven gears must be an even multiple of the number of detent positions so that each detent position unequivocally presents an index marking centered at the calibrating apertures 62 and 63. If gears having the number of teeth proper for eight detent position operation (45 between detent positions) are utilized, the switch assembly may be modified for four position detent operation (90 between the detent positions) merely by changing to a four lobe detent cam, no change in the gears being necessary.

While the invention has been disclosed and described in some detail in the drawings and foregoing description,

' they are to be considered as illustrative and not restrictive in character, as other modifications may readily suggest themselves to persons skilled in this art and within the road scope of the invention, reference being made to the appended claims.

I claim:

1. A switch assembly having a plurality of switch actuation-controlling members mounted within a housing with a plurality of cam elements each mounted to rotate independently within the housing adjacent the switch members and adapted to sequentially engage their respectively adjacent switch members as the cams rotate thereby sequentially actuating the switch members, wherein the improvement comprises a driven gear rigid with each cam, a driving gear mounted on an operating shaft for rotation within the housing, the operating shaft extending to the exterior of the housing, said driving gear meshing with each of said driven gears and rotating the driven gears upon rotation of the operating shaft, the orientation of said cams with relation to said driving gear upon initial meshing of the driving gear with the driven gears determining the sequence of actuation of said switch members, one side face of each of said driven gears being provided with a series of index markings, and a plate overlying said driven gears parallel to and adjacent said marked side faces of said driven gears, said plate having indexing apertures therein through which a portion of the index markings of the adjacent driven gear face can be viewed to facilitate the the desired index positioning of said driven gears for meshing with said driving gear.

2. A switch assembly as claimed in claim 1 in which cooperating detent means are carried by said housing and said operating shaft to establish discrete detent positions of said driving gear.

References Cited UNITED STATES PATENTS 2,368,005 1/1945 Crise.

2,574,841 11/1951 Powell et al.

2,943,161 6/1960 Fath 3,022,099 2/1962 Bruscaglioni 74568 3,036,167 5/1962 Bacchi.

3,107,548 10/1963 Goetz et al. 74--568 FRED C. MATTERN, 1a., Primary Examiner F. D. SHOEMAKER, Assistant Examiner US. Cl. X.R. 200-38, 167

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