US2491696A - Switch unit - Google Patents

Description

A. VENDITTY SWITCH UNIT Dec. 20, 1949 3 Sheets-Sheet 1 Original Filed Aug. 23, 1943 FIE-3 INVENTUR NTHONY lE/VD/TTY G 6, W 9 vw/ X 8. W V m. wwu PM! II 2 @Q mm m Dec. 20, 1949 A. VENDITTY 2,491,696

SWITCH UNIT Original Filed Aug. 23, 1943 3 Sheets-Sheet 2 FIG 4 3/ /2. 99 3 FIG 7 59 99 99 17 67 /o/ mo 3 26 47 a INVENTOH ANTHONY l E/w/rry Dec. 20, 1949 VE 2,491,696

. SWITCH UNIT Original Filed Aug. 23, 1943 3 Sheets-SheetS INVEN T U M/ THO/V) l/f/val T r BY Z fl/ WATTYS Patented Dec. 20, 1949 SWITCH UNIT Anthony Venditty, Detroit, l'iich assignor to Thompson Products, Inc., Cleveland, Ohio, a

corporation of Ohio Original application August 23, 1943, Serial lilo.

Divided and this application October 27, 1945, Serial No. 625,052

Claims. (Cl. 200 6) This invention relates to a switch unit and more particularly to a simple, compact reliable switch structure which is particularly suitable for use in controlling electric motors on equipment used or installed in the home.

This application is a division of my copending application entitled Switch unit, U. S. Serial No. 499,604, filed August 23, 1943, and assigned to the same assignee as the present invention.

One of the principal features and objects of the present invention is to provide a novel compact switch unit for controlling the flow of high voltage current such, for example, as the current usually supplied by public utility companies at 110 to 120 volts, 60 cycle A. C.

A further object of the present, invention is to provide a novel switch structure housed in a single compact assembly.

Another object of the present invention is to provide a novel switch and mounting therefor which is economical to manufacture and which is rugged and reliable in use.

The novel features which I believe to be characteristic of my invention are set forth with particularity in the appended claims. My invention itself, however, both as to its organization and manner of construction, together with further objects and advantages thereof, may best b understood by reference to the following description taken in connection with the accompanying drawings, in which:

Figure 1 is a diagrammatic view of a switch unit embodying the novel teachings and characteristics of the present invention and showing it with a motor which it is designed to control and a pushbutton switch which efiects operation of the main switch unit, the switch unit being complete and assembled except that the sealing compound is removed from the grooves in the cover;

Figure 2 is a plan view of the switch unit shown in Figure 1;

Figure 3 is a bottom view showing the under side of the cover which has been removed from the switch unit;

Figure 4 is a sectional view of the unit as shown in Figure 2 as taken along the line IV--1V thereof with the cover now in place;

Figure 5 is a sectional view of the unit with the cover in place as taken along the line VV of Fi ure Figure 6 is a section view of the unit with the cover in place as taken along the line VI VI 0! Figure 2; Figure '7 is a sectional view of the upper portion of the unit with the cover in place as taken along the line VII-VII of Figure 2;

Figure 8 is an isometric view of the solenoid bracket;

Figure 9 is a plan view of the upper housing member of the unit; and

Figure 10 is a diagrammatic illustration of an electric circuit in which the novel switch of the present invention may be employed, and indicates the utility of the switch structure.

In order to understand the problem involved. and in order to fully appreciate one of the useful circuits in which the novel switch structure of the present invention may be used, reference will first be made to Figure 10 of the drawings, wherein is diagrammatically illustrated a splitphase induction motor I I which is arranged to be energized from supply conductors l2 and I3. Supply conductors l2 and iii are arranged to be connected to a suitable source of alternating current supply, such, for example, as the conventional 110 volt 60 cycl current which is usually supplied by the public utility companies throughout the country. The motor II has four terminal connections which have been labeled R, G, O and B. Although not shown, it will be understood by those skilled in the art that the terminal connections R and B are connected to one winding of the split phase induction motor ll while the terminal connections G and O are connected to the other winding, the latter having a resistance element in series therewith.

Ihe motor I l is connected to supply conductors i2 and I3 through a switch Hi. This switch ll has six stationary contacts IE to 20, inclusive, and three movable contact bars 2|, 22 and 23 which are carried on a bar of insulating material 24 and arranged to be rocked about the longitudinal axis of this bar. The contact bar 2| is arranged to be rocked into engagement with either stationary contact l5 or stationary contact l8. Contact bar 22 is arranged to be rocked into engagement with either stationary contact It or stationary contact l9. Contact bar 23 is arranged to be rocked into engagement with either stationary contact I! or stationary contact 20. Contact bars 2| and 22 are connected together by bus 25 and to supply conductor l3 through conductor 25. Contact bar 23 is connected to supply conductor |2 through conductor 21.

Stationary contacts i5 and II are electrically connected together and to terminal B of motor through conductor 28. Stationary contacts l6 and 20 are electrically connected together and are also connected to terminal O of motor I I through conductor 29. Stationary contacts I! and I9 are electrically connected together and are also connected to terminal G of motor through conductor 30. The terminal R of motor II is directly connected to supply conductor |2 through conductor 3|.

It will be understood by those skilled in the art that when the insulating bar 24 is rocked in a counterclockwise direction as shown in Figure 10 of the drawings, movable contact bars 2|, 22 and 23 will be moved into engagement with stationary contacts l8, l9 and and the motor will operate in one direction. When the insulating bar 24 is rocked about its longitudinal axis in a clockwise direction, movable contact bars 2|, 22 and 23 will be moved into engagement with stationary contacts I5. l5 and I1, and the motor will be operated in the other direction.

The control and operating circuit for rocking the bar 24 includes a pair of solenoids 3| and 32 and a step down transformer 33. Transformer 33 includes a primary winding 34 and a secondary winding 35. The winding 34 is connected across the supply conductors l2 and i3 as shown. The ratio of the number of turns in the secondary winding 35 to the number of turns in the primary winding 34 is such that current at low voltage is supplied through conductors 35 and 31. It is preferable that the current supplied through conductors 35 and 3'! have a voltage of between 6 to 10 volts.

Conductor 36 is connected to one end of the solenoid 3| and also to one end of thesolenoid 32. The opposite end of solenoid 3| is connected to a switch contact 38 through conductor 33 while the opposite end of solenoid 32 is connected to a switch contact 40 through conductor 4|. Two additional contact elements 42 and 43 are provided which are associated with contacts 38 and 40 respectively and which are connected through conductor 31 to the lower end of secondary winding 35 of transformer 33. Contacts 38 and 42 are arranged to be closed by a movable switch element 44 while contacts 40 and 43 are arranged to be closed by a movable contact element 45. Contact elements 44 and 45 are normally biased to their open position.

Transversely mounted on the insulating bar 24 is an armature arm 45 which is made of iron or some other suitable magnetic material. When the contact 44 is closed, solenoid 3| is energized from transformer 33 and the left-hand portion of the armature 45 is pulled down, thus rocking the bar 24 in a counter-clockwise direction about its longitudinal axis. On the other hand, if contact element 45 is closed, solenoid 32 is energized and the right-hand portion of armature 4B is pulled down, thus rocking the bar 24 in a clockwise direction about its longitudinal axis.

The compact unitary nature of the invention is exemplified by the particular physical embodiment illustrated in Figures 1 to 9 of the drawings. In the form shown, a single closed housing l0 comprising lower and upper housing members 41 and 48 are provided for the transformer 33, the solenoids 3| and 32 and the switch l4.

This housing, which is preferably formed of some suitable molded material of good insulating qualities, is so shaped as to provide a transformer compartment 43, a solenoid compartment 50 and a switch compartment 5|. To this end, the lower housing member 41 has an upper wall portion 52 which extends entirely over the compartment 43. 'Downwardly extending shoulders 53 and 54 are formed at either end of the wall portion 52 to provide a suitable seat for the laminated iron core 55 of the transformer 33. The compartment 49'is further closed off by a panel 56 which extends across the lower open end of the housing member 41. As is clearly shown in Figures 4 and 6, the end wall 51 is tapered as at 53 and the wall portion 53 is tapered as at 50. This permits ready insertion of the transformer 33 through the lower opening in the housing member 41 when the panel 55 is removed.

The base wall 6| of the solenoid compartment 50 is slightly offset from the remaining base walls of the housing member 41 formed by the panel 56. The solenoids 3! and 32 are mounted on a T-shaped iron bracket 52 and secured by means of bolts 63 to the base wall portion 8|. The solenoids 3| and 32 are of conventional design and include iron cores 54 and 55 respectively. The bolts 83 are threaded into the lower end of these iron cores 64 and 55 to thus secure the solenoids in place. The bracket 52 has a cut-away portion 56 which forms a shoulder on which the armature arm 46 is arranged to be seated (see Figure 8).

A C-shaped bracket is molded as an integral part of the upper wall member 52 and includes a base portion 51 and two upstanding lips 68 and 59. This bracket supports and confines the tongue 92 at one end of the bar 24 which carries the movable contact elements 2|, 22 and 23. The armature arm 45 is secured to the bar of insulating material 24 by a bolt 33, and the central portion of arm 45 which extends beyond the end of bar 24 is slotted as at 34 (see Figure 2). This slotted portion 94 is arranged to receive the upstanding top portion 35 of the bracket 62, while the unslotted central portion of the arm 46 is arranged to be seated on the shoulder 55 of the bracket 52. The bar 24 is thus arranged for rock ing movement about its own longitudinal axis.

The bar 24 has three transverse grooves ii, 72 and I3 in the upper surface thereof which are arranged to have metal contact arms 2|, 22 and 23 seated therein. In the center of each groove ll, 12 and I3 9. pin projects upwardly therefrom. More particularly, pins 14, I5 and 15 extend through .the bar 24 as may be seen best in Figure 4'. Each of the contact arms 2|, 22 and 23 is provided with a circular opening through the center which is slightly larger than the pin, as is indicated at I1, 18 and 13 (see Figure 2). Since it is necessary to electrically connect contact arms 2| and .22, a flat electrical connector 25 is seated on the same, suitable apertures 96 being provided in the strip 25 to permit the pins 14 and 15 to extend therethrough. For a reason which will presently be apparent the strip 25 is also provided with an upstanding protuberance 91 at its center.

The ends of the contact arms 2|, 22 and 23 are provided with contact buttons which are arranged to engage the confronting buttons 8| on the stationary contacts I! to 20, inclusive. Due to the fact that the openings 11, I8 and 19 in the contact arms 2| to 23 are somewhat larger than the pins I4 to 14 it will be apparent that the contact arms 2| to 23 may have limited rocking movement on the bar 24 about one or the other end of each of their associated grooves, depending upon which direction the bar 24 is rocked.

The bar 24 is resiliently held in place by a pair of coil springs 82 and 83 which are seated in the recess portions 84 and 85 respectively of the upper housing member 48. The lower end of the coil spring 82 is seated directly on the contact strip 25 over the protuberance 91, while the lower end of the coil spring 83 extends over the pin 18 and is seated on the contact arm 23.

It will thus be clear that not only is the bar 24- resiliently held in place, but the contact arms 2|, 22 and 23 are also resiliently held in their respective recessed seats on the bar 24.

The upper surface of the upper housing member 48 is provided with four transverse grooves 86, 81, 88 and 89 which are preferably of the shape and configuration as illustrated in Figures 4, 6, 7 and 9 of the drawings. As either end of each transverse groove 85 to 89, a copper or brass bushing 98 extends through the wall of the upper housing member 48. As is clearly shown in Figure 6 of the drawings, the bushings 98 in each of the grooves 86, 81 and 88 are arranged to receive the stationary contact buttons 8|. The upper end of each bushing 98 is threaded and set screws 9| are threaded therein. Each of the two bushings 98 in the end groove 89 is provided with a set screw 98 at the outer end and also a set screw 99 at the inner end.

The terminal set screws 98 are arranged to be connected to the A. C. supply conductors I2 and I8 (as shown diagrammatically in Figures 1 and 10). The set screws 99 (which are electrically connected to screws 98 through the bushings 98) clamp the ends of the conductors I88 and IN leading from the primary 34 of the transformer. They also receive and clamp pigtail conductors 28 and 21 wh ch extend from contact arms 22 and 23 respectively.

A partition wall I82 between grooves 81 and 88 in the upper housing member 48 is broken out as at I83 to permit conductors I84 and I85 to extend therethrough. As shown in Figure 10, conductor I84 connects contact buttons I1 and I9, while conductor I85 connects buttons I8 and 28. Contact buttons I5 and I8 are connected together by a conductor I88 which extends across the bottom of the groove 88.

Since the electrical connections between the motor II and the unit I8 are designed to be permanent, the grooves 88 and 89 are preferably filled with an insulating compound of the type which hardens when cooled and forms a substantially permanent part of the housing member 48.

The upper and lower hous ng members 48 and 41 are secured together by bolts I81. A pair of feet I88 may be molded or otherwise formed in the lower housing member 41 to enable the unit to be secured in any desired position.

Low voltage push button switches 44 and 45 are preferab y contained in a small separate housing I89, while the conductors 39. 4| and 31 which connect the push button switches 44 and 45 to the control circuit of the main switch contained in the unit I8 are preferably confined in a single cable I I8. The conductors 39, 4| and 31 are connected respectively to guiding posts III, 2 and 3 on the exterior end wall 4 of the lower housing member 41. The electrical connections between the push button switches 44 and 45 and the main unit I8 are arranged to be made by any inexperienced person, and since only low voltage flows in this external circuit no professional electrician is required. The conductors 28, 29, 38 and 3| which extend between the motor II and the unit I8 are preferably contained in a well insulated cable 5. the connections at both ends being made substantially permanent at the factory at the time that the motor II and the unit I8 are assembled. Although relatively high voltage flows through the conductors in the cable II5, it is not necessary to have a professional electrician since nochange is to be made in these connections at the time that the motor II- is installed. .The alternating current power source is connected to the unit I8, as previously described, to conductors I2 and I3. These conductors I2 and I3 are preferably contained in a cable I I6 having a male plug member I I1 at their ends which is arranged to be plugged into a conventional volt 60 cycle alternating current socket (not shown).

When the motor II and the unit I8 are installed in a position where the motor is to be used (such, for example, as in a private garage for operating the main garage doors), the power supply cable I I6 is plugged in by the male plug member 1 into a suitable outlet box. The box I89 containing the push button switches 44 and 45 is then mounted any place desired and a cable is run from the box I89 to the terminals III, 2 and N3 of the unit 8. When the push button switch 44 is depressed, the solenoid 3| is energized and the bar of insulating material 24 is rocked in a counter-clockwise direction as viewed in Figure 10. This causes the movable contact arms 2|, 22 and 23 to engage the stationary contact buttons I8, I9 and 28 respectively. Similarly, when the push button 45 is'depressed rather than push button 44, solenoid 32 is energized and the bar 24 is rocked in a clockwise direction about its own longitudinal axis to cause the contact arms 2|, 22 and '23 to make an electrical contact with their associated stationary contact buttons I5, I6 and I1 respectively. Figure 5 shows the position of the movable contact arm 2| as it is moved into position against its associated stationary contact I5. It will be observed that not only is the bar 24 rocked in a clockwise direction about its longitudinal axis, but the arm 2| itself has a rocking movement with respect to the bar 24. This rocking movement of contact arm 2| with respect to the bar 24 is a relative counterclockwise movement of the arm 2|. This causes a wiping action between the contact button 88 on the end of the arm 2| over the contact button 8| which forms the stationary contact I5. Furthermore, due to the fact that the coil spring 82 tends to retain the contact arm 2I seated fiat in its associated recess 1| in the bar 24, it will be apparent that the contact button 88 is held resiliently pressed against the contact button 8|. A similar action occurs between the other confronting contact buttons upon movement of the bar 24 to one or the other of its extreme positions.

When both solenoids 3| and 32 are deenergized, the springs 8'2 and 83 cause the bar 24 to remain in its intermediate position as shown in Figure 6.

While I have shown a particular embodiment of my invention, it will, of course, be understood that I do not wish to be limited thereto, since many modifications may be made and I therefore contemplate, by the appended claims, to cover allsuch modifications as fall within the true spirit and scope of my invention.

I claim as my invention:

1. A switch unit comprising a supporting structure, an elongated member mounted on said supporting structure for rocking movement about its longitudinal axis, two groups of stationary contacts on said supporting structure on opposite sides of said elongated member, a plurality of contact arms seated in a transverse position on said elongated member, means for resiliently holding said contact arms in seated engagement against said elongated member, said contact arms being free to have relative rocking movement about either side edge of said elongated member and against the resilient action of said means about an axis above said elongated member, said contact arms and said two groups of stationary contacts being positioned so that one group of stationary contacts are engaged by said arms when said elongated member is rocked on its axis in one direction and the other group of stationary contacts are engaged by said arms when said member is rocked on its axis in the other direction, and means for rocking said elongated member.

2. A wiping contact pressure switch comprising supporting means, a stationary contact on said means, a member pivotally mounted for rocking movement on said means, a contact arm seated on said member, means for resiliently urging said arm in a straight line downwardly against said member, said arm having a contact portion arranged to engage said stationary contact when said member is rocked, said contact arm being initially moved about the pivot axis of said member until said contact portion engages said stationary contact, and said contact arm thereafter having relative angular movement about an edge of said member and movement in line with said resilient means against the resilient action of said resilient means, whereby a wiping pressure contact is made between said contact portion and said stationary contact.

3. A double throw switch comprising supporting means, an insulated member mounted on said supporting means means and arranged for limited rocking movement, a pair of stationary contacts disposed on opposite sides of said rocking member, said member having a surface presenting a generally flat seat, a contact arm having contact portions at opposite ends arranged to engage said stationary contact, said contact arm being seated on said seat, means providing a movable pivot for said contact arm above said seat, means resiliently urging said arm against said seat, said pivot above said seat being movable in a line corresponding to the line in which said resilient means acts, and means for rocking said insulating member to selectively place one of said contact portions of said arm in engagement with one of said stationary contacts, said contact arm being initially moved about the axis of rock of said insulating member by movement of the latter until one of said contact portions engages one of said stationary contacts, and said contact arm thereafter having relative angular movement with respect to said insulating member about an edge of said seat surface and about said movable pivot, whereby a slidin pressure contact is made between said contact arm and said stationary contacts.

4. A switch unit comprising supporting structure, a member mounted on said supporting structure for pivotal movement, at least one stationary contact on said supporting structure, at least one contact arm having an opening in the center thereof, a pin projectin from said memher and loosely receiving the opening in said contact arm for relative rocking motion of the arm on said pin, means for resiliently holding said contact arm in seated engagement on said pin of said elongated member and for permitting said relative rocking motion of the arm against the resilient opposition thereof, said contact arm being initially moved about the pivot axis of said member until said arm engages said stationary contact, and said contact arm thereafter having relative rocking movement about an edge of said elongated member as well as with respect to said pin against the resilient opposition of said resilient means, whereby a wiping pressure contact is made between said contact arm and said stationary contact.

5. A compact switch unit comprising an insulating housing including upper and lower housing members, an elongated member'mounted on said lower housing member for rocking movement about its longitudinal axis, two groups of stationary contacts on said upper housing member on opposite sides of said elongated member, a plu rality of contact arms seated in a transverse position on said elongated member, means for resiliently holding said contact arms in seated engagement on said elongated member, said contact arms being free to have relative rocking movement about the side edges of said elongated member and against the resilient action of said means about said elongated member, said contact arms and said two groups of stationary contacts being positioned so that one group of stationary contacts are engaged by said arms when said elongated memberis rocked in one direction and the other group of stationary contacts are engaged by said arms when said member is rocked in the other direction, and a low voltage switch operation mechanism for rocking said elongated member and disposed in said lower housing.

ANTHONY VENDIT'I'Y.

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

UNITED STATES PATENTS Number Name Date 1,559,110 Leddick Oct. 27, 1925 1,654,646 Hartwig Jan. 3, 1928 1,782,916 Campbell Nov. 25, 1,930 1,796,449 Getchell Mar. 17, 1931 1,869,330 Anderson July 26, 1932 2,446,299 Nelsen Aug. 3, 1948

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