US2528520A

US2528520A - Solenoid operated switch

Info

Publication number: US2528520A
Application number: US748730A
Authority: US
Inventors: Wilbur C Jackson; Louis T Clemens
Original assignee: Motorola Inc
Current assignee: Motorola Solutions Inc
Priority date: 1947-05-17
Filing date: 1947-05-17
Publication date: 1950-11-07
Anticipated expiration: 1967-11-07

Description

1950 w. c. JACKSON EIAL 2,528,520

SOLENOID OPERATED SWITCH Filed llay 17, 1947 INVENTORS. dbl/,7 0T Jae/550m BY Zazu'sTCZemezzs, M

Patented Nov. 7, 1950 UNITED STATES PATENT OFFICE SOLENOID OPERATED SWITCH Wilbur 0. Jackson, Oak Park, and Louis '1'. Clemens, Chicago, Ill., assignors to Motorola,

Inc., a corporation of Illinois Application May 17, 1947, Serial No. 748,730

5 Claims. (Cl. 200-87) 1 2 This invention relates generally to switches and Fig. 2 is an end view showing the exposed end more particularly to remotely controlled solenoid operated step-by-step switches.

In the prior art the use of remotely operated switches in various types of control systems are well known. Very small remotely controlled switches of this type have generally been unsatisfactory i'or one or more of the following reasons;

a comparatively large amount of power is required for operating the switch, the switch tends to be noisy in operation, the movable contact may become jammed and not make good connection upon operation, and vibration of the switch causes the movable contact to creep oil the fixed contacts. Further, in various types of control circuits a remotely controlled switch is required which can be used to selectively provide a plurality of different contact closing positions. Switches of this type have been generally complicated and expensive and have been objectionably large for use in many applications.

It is, therefore, an object of this invention to provide a small remotely controlled switch which is dependable in operation.

It is a further object of this invention to provide an improved electrically operated switch arranged for step-by-step movement to provide a plurality of difierent connecting positions.

A ieature of this invention is the provision of a switch having a solenoid operated plunger carrying a contact member which is rotated in response to reciprocal movement of the plunger to change the position of the contact member.

A further feature of this invention is the provision of a reciprocally and rotatably movable contact member having radially extending projections and a terminal support member including teeth which engage the projections to cause rotation of the contact member in response to reciprocation thereof and which prevent rotation of said" contact member when the contact member is at rest.

A still further feature of this invention is the provision of a solenoid'operated switch including a contact member movable in one direction by the solenoid and in the opposite direction by a spring, the spring being further adapted to hold the movable contact in firm engagement with fixed contacts and to make electrical contact thereto.

Further objects, features and advantages will be apparent from a consideration of the following description taken in connection with the accompanying drawings in which:

Fig. 1 is an elevation view of the switch in accordance with the invention;

of the terminal member; s

Fig. 3 is a cross-sectional view along the lines 3-3 of Fig. 2;

Fig. 4 is a cross-sectional view along the lines H of Fig. 3;

Fig. 5 is a diagrammatic view illustrating the movement of the contact member of the switch;

Fig. 6 is aperspective view of the contact member;

Fig. 7 illustrates a modified switch in accordance with the invention; and

Fig. 8 shows the terminal member of the modified switch.

In practicing our invention we provide a solenoid operated switch including a tubular housing having a coil at one end thereof and a magnetic core adapted to be drawn within the coil when the coil is energized. The magnetic core is a part of a reciprocating plunger structure which includes a contact member rotatably supported thereon. The contact member is of generally annular configuration ,having radial projections on the periphery thereof. A terminal member is provided in the end of the housing opposite to the coil and includes a plurality of projecting teeth adapted to engage the projections on the contact member. The terminal member also includes a plurality of fixed contacts and the contact member includes a conducting portion which is adapted to engage the fixed contacts. A spring is provided to normally hold the plunger in a position in which the core is substantially withdrawn from the coil and the conducting portion is in engagement with the fixed contacts. The switch housing includes inwardly extending portions having slanting edges which engage the projections of the contact member when the plunger is moved by movement of the core into the solenoid to rotate the contact member. When the solenoid is deenergized the spring moves the plunger to the normal position and the teeth of the terminal support member engage the projections on the contact member to further rotate the contact. Therefore, it is seen that reciprocal movement of the plunger causes rotation of the contact member which results in the engagement of difierent fixed contacts by the conducting member.

Referring now to the drawings, in Figs. 1 to 6, inclusive, there is illustrated a switch including a housing It and a terminal support member H having a plurality of terminals l2 thereon. The terminal support member N forms a closure for one end of the tubular housing l0, the other end of which is closed by an annular member I; having a mounting stud l4 secured therein. The solenoid driving unit comprises a coil l5 wound on a coil form including a tubular spool l6 and annular end members [1 which are supported within the housing It. The mounting stud l4 includes a shoulder it against which one end of the spool it rests to position the coil within the housing. A reciprocal plunger unit is provided including an iron core l9 having an end of such configuration to provide a sliding fit within the spool it. The end 20 supports one end of the plunger, the other end being supported by a pin 2| which is secured to the core and is slidably positioned in an opening 22 in the terminal support member II. The pin 21 and the opening 22 are of the same irregular configuration so that the pin cannot rotate in the opening, a square pin and opening being illustrated in the drawings.

The movable plunger further includes a contact member which is rotatably supported on the iron core [9. An annular rim 23 and a spunover edge 24 on the core l9 engage the sides of the contact member 25 to cause the member to move longitudinally with the core but permitting rotation of the member'with respect thereto. The detailed construction of the contact member 25 is apparent from Figs. 3, 4 and 6 in which the contact member is illustrated as including an annular disc 26 having projections 21 radially spaced about the periphery thereof. Conducting

members

28 and 29 are provided on either side of the insulating member, the conducting member 28 including bent up contact engaging portions 30 on opposite sides thereof.

The conducting members are secured to the insulating member 26 by a pair of rivets 3| which secure the contact member together as an assembly and also electrically connect the two conducting members. As shown in Fig. 3, the contact engaging portions 30 engage contacts 32 in the terminal support member H, the contacts 32 being secured to the terminals I2 in any suitable manner.

As is apparent from Figs. 3 and 5, the terminal support member ll includes a plurality of projecting teeth 35 which extend along the inner wall of .the housing It. The number of teeth 35 onthe terminal member is equal to the number of projections 21 on the contact member, the projections being arranged to engage the teeth 35 when the contact member is moved to rotate the contact member as will be explained. The housing It includes inwardly extending 011- set portions 35 having slanting edges 31 which are positioned in the path of the contact member 25 and engage the projections 21 thereof to cause rotation ofthe contact member 25.

A spring is provided for holding the plunger in the position in which the contact engaging portions 30 engage'the. fixed contacts 32. The

ends of the spring are positioned against one of the coil forms I! and the annular rim 23 of the 4 I 35 and six fixed contacts 32. Movement of the plunger is caused by energization of the coil I5 which draws the core l9 therein as shown by the dotted lines in Fig. 3. A circuit including a source of energy 43 and a remote switch 44 is illustrated for energizing the coil l5. This, of course, causes the contact member 25 to be drawn toward the coil to the position shown in dotted lines. As previously stated, the oflset portions 36 of the housing are in the path of the projections 21 on the contact member and as the contact member 25 is drawn toward the coil l5, the projections 21 will engage the slanting edges 31 of the ofiset portions causing rotation of the contact member. This operation is clearly shown in Fig. 5 wherein the motion of one projection 21 designated as 21a is shown by dot-dash lines. Movement of the projection 21a to the left will cause the projection to engage the slanting edge 31 and follow this edge until movement of the projection to the left is stopped. When the coil [5 is deenergized and the spring 40 moves the plunger to the right, the projection 21a will engage the tooth 35 indicated as 35a and follow the slanting edge of the tooth to the V-shaped groove between the tooth 35a and the next tooth marked 35b. Therefore, it is seen that the reciprocal movement of the contact member causes each projection 21 to be rotated from a position between a pair of teeth to the next succeeding position and so on.

In a switch having six projections and six teeth as illustrated. each movement causes rotation of the contact member through /6 of a complete revolution or through degrees. It is apparent from Figs. 4 and 6 that this will cause the conducting member 28 to be moved from a position in which it bridges a pair of oppositely positioned fixed contacts 32 to a position in which it bridges the next pair of oppositely positioned contacts. Therefore, successive step-by-step operation of the switch provides three different contact closing positions provided by each of the three pairs of oppositely positioned fixed contacts in the terminal support member I I. It is obvious, however, that instead of providing six contacts (three pairs) and six projections 21 on the contact member and six projecting teeth 35, any other number can be used depending upon the particular requirements.

The switch may be used in various manners as will now be explained. In the structure shown, the conducting member 23 in addition to bridging a pair of contacts 32 connects the contacts to the housing II. This connection is made from the conductingmember 23 through this rim to spring 40 which engages the coil end plate 11. Asthe end plate I! is made of ferrous metal. it is conducting and the circuit is completed therethrough to the housing Hi. Therecore I! as clearly shown in Fig. 3. The spring able contact member 25 includes six projectionsv 21 on the periphery thereof, and the terminalsupport member. H likewise includes six teeth fore, by grounding the mounting stud H or connecting it to any circuit, the contacts 32 engaged by member 28 ar connected to this circuit. If it is desired to use the switch only to bridge contactsand not connect them to another circuit, the conducting plate 23 maybe eliminated and the bridged contacts will then be insulated from the housing and operating structure of the switch.

Figs. 7 and '8 illustrate a modified terminal member and contact member which have utility in other circuits. .The terminal'member 53 has contacts 5| thereon arranged in two concentric factory in use.

rows, and the movable contact member 52 includes a conducting member 53 in which the contact engaging portions 54 and I! are positioned .so that the portion 54 will selectively engage the contacts in each row, a total of six diiferent circuit bridging positions is obtained instead of three positions as in the modification previously described. As explained with respect to the structures of Figs. 1 to 6, the fixed contacts instead of merely being bridged together can be grounded or connected to any other circuit by making connections through the plunger return spring to th housing and the mounting stud.

Switches constructed in accordance with the invention have been found to be very dependable in operation and to be generally very satis- The original rotational movement' of the contact member 25 by the offset portions 36 on the housing is smoothly accomplished without jamming of the contact due principally to the fact that two offset portions are provided. This causes rotational movement of two oppositely positioned projections as is clearly shown in Fig. 4 providing a balanced torque whichtends to eliminate jamming of the contact member when it is moved by the eflect of the coil IS on the core It. When the contact member moves in the direction toward the fixed contacts under the force of spring 40, a very' smooth turning movement is provided which prevents jamming of the contact member and results in a firm connection between the contact engaging portions Ill and the fixed contacts 32. This movement of the plunger by the spring 40 results in each of the projections 21 resting on the slanting surface of one of the teeth 35 eliminating any tendency for the contact member 35 to tilt or jam. The projections follow the slanting surfaces of the teeth to the grooves between the teeth where they rest until the switch is again operated.

The operation of the switch in accordance with the invention is accomplished with the use of a relatively small amount of electrical energy due to the efiicient magnetic circuit provided. Referring to Fig. 3, this circuit extends through the right end member ll, housing l0, left end member I! and the movable core 20. The end plate l3 may also be of magnetic material further reducing the reluctance of the magnetic circuit. The switch has been found to be very dependable, movement of the plunger being fast and relatively quiet. Th structure disclosed is simple and can be very inexpensively manufactured. Each of the components can b either punched or molded and as the configuration of the components is not 'unduly critical, high speed production line methods can be used in manufacture. The switch is adaptabl to construction as a very small unit and is rugged and not subject to defective operation due to vibration thereby making it particularly applicable for use in vehicular installations or in other conditions where vibration is present. Although we have disclosed certain embodiments of our invention, it is apparent that various modifications and changes can be made therein without departing from the intended scope of the invention as defined by the appended claims.

We claim:

1. A solenoid operated switch comprising a tubular housing, a coil positioned within said housing at one end thereof, a movable plunger including a magnetic core adapted to be drawn into said coil, a contact member rotatably mounted on said plunger and having a plurality of radial projections thereon, said housing having an offset portion with an inwardlyextending slanting edge adapted to engage said projections when said core is drawn into said coil to rotate said contact member, a sprin tending to hold said plunger away from said coil, and a terminal support member at the end of said housing opposite to said coiland including a plurality of contacts and a plurality of teeth positioned to engage said projections to cause further rotation of said contact member when said plunger is moved away from said coil by said spring.

2. A step-by-step switch comprising a housing, a plunger mounted for reciprocal movement within said housing, a contact member rotatably mounted on said plunger and having a plurality of radial projections thereon, said housing having ofiset portions including inwardly extending slanting edges adapted to engage said projections when said plunger is moved in one direction to rotate said contact member, a spring tending to move said plunger in the opposite direction, and a terminal support member at one end of said housing includiztg a plurality of teeth thereon adapted to engage said projections to cause further rotation of said contact member when said plunger is moved in said opposite direction by said spring.

3. A step-by-step switch comprising a housing, a plunger mounted for reciprocal movement within said housing, a contact member rotatably mounted on said plunger and having a plurality of radial projections thereon and a conducting member secured thereto, said housing having offset portions including inwardly extending slanting edges, a terminal support member at one end of said housing including a number of teeth equal to the number of said projections and a plurality of fixed contacts adapted to be selectively engaged by said conducting member, a spring for holding said plunger in a position in which said conducting member engages certain of said fixed contacts, and means for moving said plunger away from said one position, said means being arranged to move said conducting member away from said fixed contacts and cause said projections to engage said slanting edges to rotate said contact members, movement of said plunger to said one position by said spring upon release of said means being effective to cause said projections to engage said teeth to further rotate said contact member so that said conducting member engages different fixed contacts, said spring being efiective to hold said conducting member firmly against said fixed contacts and to make electrical contact between said conducting member and said housing.

4. A step-by-step switch comprising a housing, a plunger mounted for reciprocal movement within said housing and including a rotatable contact member having a plurality of radial projections thereon and a conducting member secured thereto, said housing having a pair of offset portions on opposite sides thereof including inwardly extending slanting edges, a terminal support member at one end of said housing including a number of teeth equal to the number of said projections and a plurality of fixed contacts adapted to be selectively engaged by said conducting member, said teeth being symmetrically positioned and having slanting edges, a spring for holding said plunger in a position in which said conducting member engages certain of said fixed contacts, and means for moving said plunger away from said one position, said means being arranged to move said conducting member away from said fixed contacts and cause a pair of oppositely positioned projections to en age said slanting edges to rotate said contact members, movement of said plunger to said one position by said spring upon release of said means being effective to cause said projections to individually engage the slanting edges of said teeth to further rotate said contact member so that said conducting member engages different fixed contacts.

5. A solenoid operated switch comprising a tubular housing, a coil within said housing and positioned at one end thereof, a movable plungerincluding a magnetic core adapted to be positioned within said coil and a contact member rotatably mounted on said core, a spring tending to hold said plunger away from said coil, an insulating terminal member at the opposite end of said housing including a number of radially spaced teeth and an equal number of radially spaced contacts thereon, said movable contact member including a conducting member adapted to bridge a pair of said contacts and an insulating disc having radial projections thereon equal in number to said spaced teeth, said housing having a pair of offset portions on either side thereof including inwardly extending slanting edges, said projections being-adapted to engage said slanting edges of said offset portions when said core is drawn into said coil to rotate said contact member in a given direction, said projections being adapted to engage said teeth when said plunger is moved away from said coil by said spring to further rotate said contact member in said given direction so that said conducting member is moved from a position bridging one pair of contacts to a position bridging a different pair of contacts, said spring tending to hold said conducting member against said contacts.

WILBUR C. JACKSON.

LOUIS T. CLEMENS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS