US2967215A - Control device - Google Patents

Description

Jam 3, 1951 H. E. wHn-ING 2,967,215

- CONTROL DEVICE Filed Nov. 25, 1957 F 6 i INVENTOR.

HAROLD E. WH/T/NG 2,967,215 Patented Jan. 3, 1961 tice coNrRoL DEVICE Harold E. Whiting, Milwaukee, Wis., assignor to Square lD Company, Detroit, Mich., a corporation of Mich- Igan Filed Nov. 25, 1957, Ser. No. 698,426

4 Claims. (Cl. 20G-6) This invention relates to control devices and more particularly, to a multiple position electric switch which has its parts constructed and arranged to accomplish a plurality of switching operations.

It is an object of the present invention to provide a switch which may have its parts arranged to accomplish a plurality of circuit opening and clos.ng operations.

Another object of the present invention is to provide a switch which has movable and stationary contacts arranged for controlling two circuits when a knob of the switch is moved to one of three positions and wherein the position of the actuating means between the knob and contacts may be varied to provide various combinations of open or closed circuits.

A further object of the present invention is lto provide a switch structure utilizing an actuating cam which may be positioned in the switch to accomplish a plurality of different switching combinations.

Another object of the present invention is yto provide an actuating cam and switch structure which may be positioned relative to each other to accomplish a tplurality of different switching arrangements.

Further objects and features of the invention will be readily apparent to those skilled in the art from the speccation and appended drawing illustrating certain preferred embodiments in which:

Fig. l is a side view showing the parts partly in section of the switch according to the present invention.

Fig. 2 is a top plan view of the switch in Fig. 1 with the mounting means, the switch knob and the actuating cam removed to show the indexing mechanism of the switch.

Fig. 3 is a bottom plan view of the kswitch in Fig. 1l

with the back switch cover removed.

Fig. 4 is a perspective view of an actuating cam as used in the switch in Fig. 1.

Fig. 5 is a perspective view of a modification of the actuating cam in Fig. 4.

Fig. 6 shows a chart illustrating the various switching combinations which may be accomplished when the cams shown in Figs. 4 and 5 are arranged rs indicated in the switch structure illustrated in Figs. 1-3.

Fig. 7 in perspective shows the stationary and movable contact assemblies.

In the drawings, the numeral 1t) designates a switch housing which is preferably formed of a molded insulating material. The switch housing for purposes of explanation will be designated rs having two sections, i.e., a contact section 12, and the actuator section 18. The contact section 12 which is rectangular in shape, encloses the pair of movable contacts assemblies 14 and the stationary contact assemblies 16 shown in Fig. 7. The actuator section 18 is shaped like a cross and encloses the actuating rod 20, the actuating cam 24 and the indexing means 22 which resiliently holds the cam 24 and rod 20 in anv one of a pluralitv of preselected positions.

The sections 12 and 18 of the housing are separated by a substantially flat wall 26 which has four spaced recesses 28 therein to provide clearance for the curved portion 3@ of the leaf springs 32 each of which carry a movable contact 34 on one end. Secured to the other end of each of the leaf springs 32 as in Fig. 7 is a stud 36 which has a rectangular cross-section and is tapped to receive a terminal screw 33. The rectangular studs 36 are each receivable in rectangular openings or bores 37 in the section -12 of the housing 10. The stationary contact assemblies 16 kof the switch also shown in Fig. 7 each include a contact tip 40 which is secured to a rigid arm 42 which in turn is secured to a stud which is identical to the studs 36 to which the movable contact leaf springs 32v are secured. When the switch is assembled, the rectangular studs 36 are merely dropped into the rectangular bores 37. The bores 37 are located to align the movable contacts 34 with the stationary contacts 40. The Contact assemblies 14 and 16 are maintained in the housing by the back cover plate 44 which is secured by screws 46 which are threaded into tapped holes in the divider 48 which is located as shown to separate the cooperating stationary and movable contact assemblies 12 and 14.

The cut-out portions at each of the corners of the cross-shaped section V18 are arranged to expose the terminal screws 38 to the front of the switch. In this connection it is to be noted that ythe use of rectangular studs 36 in rectangular bores 37 will permit the terminal screws 38 to be tightened securely without cracking or otherwise injuring the molded material which forms the switch housing 1t).

Extending through the wall 26 and divider 48 between sections 12 and 18 of the housing is a circular bore 50. Also extending through the wall 26 are a pair of guide slots 52 which are parallel to and spaced on opposite sides of the bore 50. 'The slots '52 are aligned with the arm portions of the leaf springs 32 and are arranged to guide and position the movable actuating members 54 to cause opening and closing of the contacts 34 and 40.

The central portion of the cross-shaped actuating section '18 has a circular recess 56 therein. Extending across the recess 56 as shown are ledges 58 and extending outwardly from the recess 56 are notches 60. The notches 60 are located to position the leaf springs 62. The leaf springs 62 which form a part of the indexing means 22, each have a projection ,64 at their mid portion which is received in the detents on the periphery of the indexing cam 66 which forms another part of the indexing means 22. The .indexing cam 66 has six detents or lobes on its outer periphery and has a rectangularly shaped central opening which is aligned with the bore 50.

The actuating members 54, as shown, each have one end thereof inclined at an angle to provide the maximum surface contact with the inclined surface of the arm portions of leaf springs 32. The other end of the members 54 has an apex thereon to ride upon the cam surfrces of the actuating cam 24, most clearly shown in Figs. 4 or 5. During assembly of the switch the actuating member 54 are merely dropped into the slots 52 before the cam k24 is installed in the housing. 'In this connection it is to be noted that the top surfaces of ledges 58, the guides for the actuating members 54, the indexing cam v66 and the indexing springs 6i) are preferably arranged contact section is milled to provide a shoulder which engages the inner surface of the lug 70 which is located in bore 50 as shown. A remaining unmilled end portion '72 of the rod extending from the shoulder to the end of the rod is arranged to bypass the lug 70 and engage the back cover plate S. The unmilled end portion 72 is arranged to engage the lug 70 to limit the rotation of the rod 20 in the switch housing 10.

The rod is also provided with a shoulder 73 which engages the front cover plate 74 of the switch. Extending outwardly from shoulder 73 a circular cross-sectional portion 75 extends through a circular opening in the cover plate which provides a bearing for the rod 20. The circular end portion 75 of the rod which extends external to the cover plate 74 is milled in the conventional manner to provide a non-rotatable securement for a switch actuating knob 76.

The actuating cams 24, most clearly shown in Figs. 4 and 5, are preferably formed of a molded insulating material. Each of the cams 24 are circular and essentially disc shaped and have a central hub wherein the eight pointed central openings or bores 68 are located.

The cam surfaces on the member shown in Fig. 4 are located on opposite sides of the disc faces and are complernentary to each other; that is, a raised surface on one side of the disc which forms the cam 24 provides a depressed surface on the other side. In Fig. 4 on the surface indicated with an indicating square 78, the depressed surfaces 80 and 82 are radially equal in extent while the raised surfaces 84 and 86 are radially unequal.

This will be more clearly seen if it is assumed that that the indicating square 78 on the top surface of cam 24 in Fig. 4 is located on the zero axis through the center line of opening 68, the points A-H will be respectively located as follows:

Conversely, the surfaces on the opposite sides of the actuating cam will be reversed relative to the indicating pointer 34 which is on the bottom surface of cam 24 and not shown in Fig. 4 but indicated in Fig. 6. In this connection it is to be noted that the indicating pointer 83 is also located on the 0 axis of the cam 24 in Fig. 4.

in Fig. 5 of the drawings the actuating cam 24 is provided with a flat bottom surface and a top surface which has raised cam surfaces 87, 88 and 90 with the indicating circle 92 located at 0 axis through the central opening 68. Thus points A-F' will be located as follows:

Degrees A 32 From the above it will be clear that when a raised cam surface is in engagement with the apex of one of the contact actuators 54, then the switch contacts 34 and 4t2 associated therewith will be closed. Further, if a depressed surface is engaged by one of the apexes, the switch contacts 34 and 40 will be open circuit position. The raised portions of the cam 24 are arranged relative to the points in the eight pointed opening 68 so the expected contact action will occur at 45 intervals as dictated by the position of the actuating cam 24 on the 4 actuating rod. In Fig. 6 the various combinations of contact actuations are shown.

Thus, if the actuating cam 24 in Fig. 4 is positioned on the rod 20 and in the actuating section 18 so the side of the cam with the square 78 is facing the contact section 12 and the pointer is adjacent the front cover 74 as shown, then if the eight pointed opening 68 is positioned on the apexes of the actuating rod 20 in position l when the actuating rod 20 is held in the neutral position by indexing means, if the knob 76 is turned from the neutral position N to the left to position L one of the contacts will move from the open position to the closed position. When the knob 76 is turned in the opposite direction or to the right past the neutral position N wherein both contacts are open to the position R, the other pair of the pair contacts will close.

It is not be ieved further explanation of the combinations of the circuit opening and closing positions of the contacts 34 and 4t) which may be achieved by changing the position of the actuating cams 24 on the rod 20 as shown in Fig. 6 is necessary to the understanding of the present invention. It is clearly apparent that the cams shown in Figs. 4 and 5 when positioned on the actuating rod 20 in the seven positions indicated by the pointer 83, the square 78 or the circle 92 in positions 1 7 will provide a variety of open and closed contact positions when the switch is actuated from the neutral position N either to the left to the position L, or to the right to the position R.

While certain preferred embodiments of the invention have been specifically disclosed, it is understood that the invention is not limited thereto, as many variations will be readily apparent to those skilled in the art and the invention is to be given its broadest possible interpretation within the terms of the following claims.

What is claimed is:

1. In an electric switch, the combination comprising; a switch housing having a plurality of spaced openings of square cross-section extending between two surfaces of the housing, a plurality of stationary and movable contact assemblies, each assembly having a stud complementary in shape to said openings and slideable therein said assemblies being interchangeable in the openings, a terminal screw accessible externally of the housing and threadedly received by each of the studs and means including a cover plate for the housing for maintaining the studs in position in the housing.

2. In an electric switch, the combination comprising; a switch housing having a plurality of spaced shaped opening of square cross-section extending between two opposed surfaces of the housing, a plurality of stationary and movable contact assemblies each having a stud with a shape complementary to the openings and slideable therein and arranged to extend between said opposed surfaces said assemblies being interchangeable in the housing, a terminal screw accessible externally of the housing and threadedly received in each of the studs and a cover plate securable to one of said opposed surfaces for maintaining the assemblies in position in the housing and permitting the terminal screws to be accessible to the other opposed surface of the housing.

3. In a multiposition electric switch, the combination comprising; a switch housing, a rod having a rectangular cross-sectional shape rotatable in either direction from a neutral position in the housing, an indexing means arn ranged for resiliently maintaining the rod in any one of three positions, means on said housing engageable with a portion of the rod for limiting the movement of said rod between the three positions, a pair of spaced movable contacts engageable with a pair of stationary contacts, a pair of contact actuators for moving the movable contacts and a means comprising a disc-like cam having an eight pointed central opening for receiving the rectangular cross section rod and moving the actuators in response to the rotation of the rod in the housing, said disc-like cam having a pair of cam surfaces extending from the opposite disc faces and wherein one of the cam surfaces on each side of the disc is of different chordal length than the remaining cam surfaces and wherein the cam may be positioned on the actuating rod so either of said pair of cam surfaces is engageable with the actuators.

4. In a multiposition electric switch, the combination comprising; a switch housing, a rod having a rectangular cross-sectional shape rotatable in either direction from a neutral position in vthe housing, an indexing means arranged for resiliently maintaining the rod in any one of three positions, means on said housing engageable with a portion of the rod for limiting the movement of said rod between said three positions, a pair of spaced movable contacts engageable with a pair of stationary contacts, a pair of contact actuators for moving the movable contacts and a means comprising a disc-like cam having an eight pointed central opening for receiving the rectangular cross section rod and moving the actuators in response to the rotation of the rod in the housing, said 6 disc-like cam having an eight pointed central opening and having complementary cam surfaces extending from opposite faces of the disc wherein at least one of the cam surfaces on one side of the disc is of different chordal length than the remainder and wherein the cam may be positioned on the actuator rod so either of the complementary cam surfaces lis engageable by the actuators.

References Cited in the file of this patent UNITED STATES PATENTS 1,302,035 Hall Apr. 27, 1919 1,738,140 Despard Dec. 3, 1929 2,182,715 Yeske Dec. 5, 1939 2,203,236 Randolph June 4, 1940 2,233,124 Furnas Feb. 25, 1941 2,319,503 Glogau May 18, 1943 2,701,450 Duncan Feb. 8, 1955 2,727,956 Winter Dec. 20, 1955 2,848,574 Hutt Aug. 19, 1958

Images