US3403236A

US3403236A - Electrical switch having a one-piece actuator and spring arm structure

Info

Publication number: US3403236A
Application number: US628601A
Authority: US
Inventors: Richard S Zoludow
Original assignee: Robertshaw Controls Co
Current assignee: Robertshaw Controls Co
Priority date: 1967-04-05
Filing date: 1967-04-05
Publication date: 1968-09-24
Anticipated expiration: 1985-09-24

Description

P 1968 R. s. ZOLUDOW 3,403,236

' ELECTRICAL SWITCH HAVING A ONE-PIECE ACTUATOR AND SPRING ARM STRUCTURE Filed April 5, 1967 5 Sheets-Sheet l FIG} 7 I BY f ms ATTORNEYS p 24, 1968 R. s. ZOLUDOW ELECTRICAL SWITCH HAVING A ONE-PIECE ACTUATOR AND SPRING ARM STRUCTURE Flled ADIll o 1967 5 Sheets-Sheet .2

FIG.6

IFIG.7

' INVENTOR RICHARD s-..z0| uoow HIS ATTORNEYS p 24, 1968 R. s. ZOLUDOW 3,403,236

ELECTRICAL SWITCH HAVING A ONE-PIECE ACTUATOR AND SPRING ARM STRUCTURE 5 Sheets-Sheet 15' Filed April '5, 1967 FIG.8

IIN'VENTOR RICHARD s. ZOLUDOW BY d404,;

ms ATTORNEYS p 1 R. s. ZOLUDOW 3,403,236 ELECTRICAL SWITCH HAVING A ONE-PIECE ACTUATOR AND SPRING ARM STRUCTURE Flled ADIll a 1967 v 5 Sheets-Sheet 4 AFIGJO INVENTOR RICHARD $.ZOLUDOW BY Y HlS ATTORNEYS United States Patent 3,403,236 ELECTRICAL SWITCH HAVING A ONE-PIECE ACTUATOR AND SPRING ARM STRUCTURE Richard S. Zoludow, South Bend, Ind., assignor to Robertshaw Controls Company, Richmond, Va., a corporation of Delaware Filed Apr. 5, 1967, Ser. No. 628,601 Claims. (Cl. 20067) ABSTRACT OF THE DISCLOSURE This disclosure relates to an electrical switch construction having a housing means pivotally carrying a pair of lever means respectively having electrical contact means on the opposed ends thereof and being fulcrumed intermediate their opposed ends on stationary terminal means carried by the housing means, the housing means carrying a pivotally mounted actuator having resilient and in tegral arms extending therefrom and respectively bearing against the pivotally mounted lever means to pivot the same from one pivotal position thereof to another pivotal position thereof with a snap action to respectively engage or disengage like contact means of the lever means from cooperating stationary contact means of the housing means to or from other stationary contact means of the housing means. Each resilient arm is so constructed and arranged that the same not only generates a downward compressive force against its respective lever means, but also during transfer of movement, the same exerts a force longitudinally in the direction of movement of the arm to impart a crisp and instantaneous snap transfer movement to the lever means to move the same between its operating positions.

This invention relates to an improved electrical switch construction means.

In particular, the various embodiments of the switch construction means of this invention each comprises a novel low cost, manual push button type of electrical switch wherein the operating mechanism is reduced to a minimum number of relatively simple parts while still providing a unique snap acting operation not provided by similar types of electrical switches.

For example, the switch construction of this invention includes a housing means pivotally carrying a lever means having electrical contact means thereon that will cooperate with fixed contact means carried by the housing means. An actuator means is movably carried by the housing means and has integral resilient arm means bearing against the lever means in such a manner that the arm means generates a compressive spring force downwardly against the lever means while during movement of the actuator means, a spring force of the arm means also is generated longitudinally in the direction of movement of the arm means to impart a crisp instantaneous snap transfer movement to the lever means as the same is moved from one operating position thereof to another operating position thereof.

Therefore, it is an object of this invention to provide an improved electrical switch construction means having one or more of the novel features set forth above or hereinafter shown or described.

Other objects, uses and advantages of this invention are apparent from a reading of this description which proceeds with reference to the accompanying drawings forming a part thereof and wherein:

FIGURE 1 is a top perspective view of one embodiment of the improved electrical switch construction means of this invention.

FIGURE 2 is a cross-sectional view taken on line 22 of FIGURE 1 and illustrates the switch construction means in one operating position thereof.

FIGURE 3 is a view similar to FIGURE 2 and illustrates the switch construction means of FIGURE 2 during part of a switching transfer operation.

FIGURE 4 is a view similar to FIGURE 3 and illustrates the actuator in another transfer position thereof.

FIGURE 5 is a view similar to FIGURE 4 and illustrates the switch construction means of FIGURE 2 in another operating position thereof.

FIGURE 6 is a cross-sectional'view taken on line 6-6 of FIGURE 2.

FIGURE 7 is a cross-sectional view taken on line 77 of FIGURE 6.

FIGURE 8 is an exploded perspective view of various parts of the switch construction means of FIGURE 1.

FIGURE 9 is a view similar to FIGURE 2 and illustrates another embodiment of the electrical switch construction means of this invention.

FIGURE 10 is a view similar to FIGURE 9 and illustrates the switch construction of FIGURE 9 in an intermediate operating position thereof.

FIGURE 11 is a view similar to FIGURE 9 and illustrates the switch construction means in another operating position thereof.

FIGURE 12 is a view similar to FIGURE 2 and illustrates still another embodiment of the electrical switch construction means of this invention.

FIGURE 13 is a view similar to FIGURE 12 and illustrates the switch construction means of FIGURE 12 in an intermediate operating position.

FIGURE 14 is a view similar to FIGURE 12 and illustrates the switch construction means of FIGURE 12 in another operating position thereof.

While the various features of this invention are hereinafter described and illustrated as being particularly adaptable for providing a push button, electrical switch construction means, it is to be readily understood that the switch construction means could readily be of a bat type, toggle type or other design whereby this invention is not to be limited to only the embodiments illustrated in the drawings, because the various features of this invention can be utilized singly or in any combination with each other to provide other types of electrical switch construction means for other uses as desired.

Referring now to FIGURES 18, an improved electrical switch construction means of this invention is generally indicated by the reference numeral 20 and comprises a housing means 21 carrying a first set of fixed terminal means 22, 23 and 24 and a second set of fixed terminal means 25, 26 and 27 each being received in a respective slot means 28 formed through the bottom wall means 29 of the cup shaped housing means 21 and being held in a fixed position therein not only by a press fit relationship as illustrated, but also by an outwardly bent or deformed portion 30 on the respective terminal means engaging against a shoulder means 31 of the housing means 21 defined by the respective slot means 28 as illustrated in FIGURE 2.

To like

lever members

32 and 33 are provided for the switch construction means 20 and each has an intermediate depression or contour 34 formed in the bottom surface thereof and medially between

opposed ends

35 and 36 thereof to rest on and pivot against the respective intermediate terminal means 23 or 26 at the rounded top edge 37 thereof that projects into the interior chamber 38 of the cup-shaped housing means 21, each set of terminal means 22-24 and 25-27 being electrically insulated from each other by an intermediate wall 39 of the housing means 21 that divides the chamber 38 into two compartments or cavities 40 and 41 adjacent the bottom wall means 29 of the housing means 21.

The lever means 32 is an electrical current carrying member and has

electrical contacts

42 and 43 secured thereto at the

opposed ends

35 and 36 to respectively cooperate with the

upper contact ends

44 and 45 of the fixed terminal means 24 and 22 in a manner hereinafter described. Similarly, the lever means 33 is an electrical current carrying member and carries electrical contacts 46 and 47 at the

opposed ends

35 and 36 thereof to respectively cooperate with the upper contact ends of the fixed terminal means 25 and 27, only the upper contact end 48 of the terminal means 25 being illustrated in FIGURE 8 while the upper contact end of the terminal means 27 is identical to the contact end 48 of the terminal means 25 that is illustrated.

Each lever means 32 and 33 has a notch means 49 formed in the side thereof and intermediate the

opposed ends

35 and 36 thereof to receive an outwardly extending tongue or guide means 50 of the intermediate wall means 39 of the housing means 21 as illustrated in FIG- URE 7 while the opposed side of the respective lever means 32 or 33 has an outwardly directed intermediate tongue means 51 received in a groove or recess means 52 of the outer side wall means 53 of the housing means 21 as illustrated in FIGURE 7 whereby the lever means 32 and 33 are properly positioned in the cavities 40 and 41 while still being adapted for pivotal movement on the intermediate terminal means 23 and 26.

As illustrated in FIGURE 2, each lever means 32 and 33 is substantially identical in configuration and has the opposed flat and substantially

parallel end portions

35 and 36 respectively separated from each other by arcuate portions 54 and 55 having the concave sides thereof facing upwardly to respectively define

wells

56 and 57 separated from each other at an intermediate upwardly facing convex point 58 for a purpose hereinafter de scribed, the intermediate point 58 being disposed at the respective intermediate terminal means 23 or 26 as illustrated and being defined by the depression 34 previously described.

A manually movable actuator means 59 of the switch construction means 20 comprises an upper body portion 60 having outwardly directed opposed integral side pivot pin means or posts 61 adapted to be respectively snap fitted into circular recesses 62 formed in the interior surface 63 of the side wall means 53 of the housing means 21 to pivotally mount the actuator means 59 relative to the housing means 21.

The upper surface 64 of the actuator means 59 is exposed at the open end or opening means 65 of the housing means 21 in the manner illustrated in FIGURE 2 and defines a substantially V-shaped cross-sectional configuration providing opposed angularly disposed top sections 66 and 67 each being longitudinally serrated for facilitating finger engaging actuation thereof as will be apparent hereinafter.

The actuator means 59 carries two like, integral, resilient and substantially S shaped arm means 68 for respectively actuating the lever means 32 and 33 in a manner hereinafter described, the arm means 68 being under compression between the body portion 60 of the actuator means 59 and the lever means 32 and 33 when the same are assembled together.

As illustrated in FIGURE 2, each arm means 68 is adapted to be received in its respective cavity portion 40 or 41 of the housing means 21 when the actuator 59 is pivotally mounted thereto in the manner previously described and has a free end 69 adapted to always bear against its respective lever means 32 or 33 while the other end 70 thereof is offset relative to the pivot point means 61 of the actuator means 59 even though being integral therewith. Thus, it can be seen that each S shaped arm means 68 is arcuately shaped between the

opposed ends

69 and 70 thereof and is reversely curved to provide a resiliency thereto for a purpose now to be described.

When the various parts of electrical switch construction 20 of this invention have been assembled together in the manner previously described by merely inserting the parts in sequence through the open end of the housing means 21, the switch construction means 20 is adapted to electrically interconnect the

fixed terminals

24 and 27 respectively to the intermediate terminals 23 and 26 when the actuator means 59 is disposed in the position illustrated in FIGURES 1 and 2. However, when the actuator means 59 is pivoted from the position of FIGURE 2 to the position illustrated in FIGURE 5, the arm means 68 and lever means 32 and 33 are so constructed and arranged that the intermediate terminal means 23 and 26 are electrically disconnected from the

respective terminal means

24 and 27 and are respectively placed into electrical connection with the respective terminal means 22 and 25 with a unique snap transfer action now to be described.

With the switch construction 20 having the actuator means 59 disposed in the position illustrated in FIGURES 1 and 2, the arm means 68 are under compression between the ends and 69 thereof while the ends 69 are disposed in the wells 56 of the

respective levers

32 and 33 to hold the

right hand contacts

42 and 46 thereof respectively against the upper ends of the terminal means 24 and 27, the actuator means 59 being maintained in this position by the configuration of the concave cam surface means 54 of the

levers

32 and 33 until the actuator 59 is physically pivoted from the position illustrated in FIGURE 2.

When it is desired to disconnect the terminals 23 and 26 from the

respective terminals

24 and 27 and place the terminals 23 and 26 into electrical contact with the

respective terminals

22 and 25, the operator merely pushes a thumb or finger against the top surface section 66 of the actuator means 59 that is projecting out of the opening 65 of the housing means 21 to pivot or rock the actuator means 59 from the position illustrated in FIGURE 2 in a clockwise direction to the position illustrated in FIG- URE 5. However, as the actuator means 59 is pivoting in the above manner from the position illustrated in FIG- URE 2 to the position illustrated in FIGURE 3, the ends 69 of the arms 68 begin to ride or cam up along the concave surface means '54 of the

levers

32 and 33 while the

levers

32 and 33 still remain in the operating position of FIGURE 2 even though the arms 68 are being placed under additional compressive force during such pivoting movement. As the ends 69 of the arms 68 pass slightly beyond the intermediate points 58 of the

levers

32 and 33 in the manner illustrated in FIGURE 4, the slopes of the left hand concave cam surface means 55 of the

levers

32 and 33 permit the compressed arm means 68 to relax slightly. The resulting vertical compression force of the arms 68 and the lateral spring force thereof caused by the arms resistance to such compressive force, now rapidly causes the ends 69 of the arms 68 to ride down the slopes of the left hand cam surface means 55 of the

levers

32 and 33 substantially to the center of the well means 57 thereof with a crisp snap action to cause the

levers

32 and 33 to rapidly pivot on their respective terminal means 23 and 26 to the position illustrated in FIGURE 5 whereby the

contacts

42 and 46 are substantially snapped away from the upper ends of the

terminals

24 and 27 while the contacts 43 and 47 are substantially snapped into contact with the upper ends of the

terminals

22 and 25.

With the actuator means 59 now disposed in the position illustrated in FIGURE 5, the arm means 68 and cam surface means 55 of the

levers

32 and 33 are so constructed and arranged that the actuator means 59 will remain in the position illustrated in FIGURE 5 until the actuator means 59 is pivoted in a counterclockwise direction by the person pushing against the now upwardly extending top surface section 67 thereof in the manner previously described to again snap the actuator means 59 from the position illustrated in FIGURE 5 back to the position illustrated in FIGURE 2 with the aforementioned snap transferring action.

Accordingly, it can be seen that the improved electrical switch construction means 20 of this invention eliminates any walking action when the ends 69 of the actuating arms 68 reach a dead center position at the intermediate points 58 of the

levers

32 and 33 so that there is no point in the movement of the actuator means 59 where all circuits controlled by the switch construction 21 are in an open position because the only movement of the

levers

32 and 33 will be a substantially snap movement thereof whereby not only does the switch construction means 20 of this invention provide improved results, but also the switch construction means 20 of this invention provides a relatively low cost switch construction means having the parts thereof reduced to a minimum number thereof while being in a relatively simple form for rapid and easy assembly thereof. For example, it can be seen that the various parts of the switch construction means 20 can readily be assembled together by automatic assembling machines, if desired.

While the housing means 21 of the switch construction 20 previously described can be readily attached to the desired supporting structure in any desired manner for any desired purpose, the embodiment of the housing means 21 illustrated in the drawings includes .a plurality of outwardly directed spring-like integral tongues 71 on opposed sides of the housing means 21, each tongue 71 having an inner end portion 72 disposed angular-1y relative to the respective flat side wall means 73 of the housing means 21 while the upper portion 74 thereof has an outer surface means 75 provided with a plurality of steps 76 that progressively extend inwardly toward the side wall means 73 as the same approach an outwardly directed peripheral flange means 77 surrounding the open end 65 of the housing means 21.

In this manner, the housing means 21 of the electrical switch construction means 20 can be telescoped into a substantially cooperating rectangular opening of a control panel or the like whereby the peripheral edge of such rectangular opening will inwardly cam the tongues 71 until the upper ends 74 thereof are adapted to snap outwardly against the peripheral edge of such rectangular opening to hold the control panel between the upper ends 74 of the tongues 71 and the outer peripheral flange 77 of the housing means 21. Thus, it can readily be seen that the switch construction means 20 of this invention can be readily assembled to and disassembled from a control panel or the like without requiring auxiliary fastening means.

In order to assure that the actuator means 59 of the switch construction means 20 of this invention will not have the arm means 68 thereof overstressed by an operator tending to press or push the actuator means 59 beyond the operating positions illustrated in FIGURES 2 and 5, the housing means 21 can be provided with an inwardly directed annular shoulder means 78 in the manner illustrated in FIGURES 2, 5 and 8 and against which the lower surface 79 of the body portion 60 of the actuator 59 will engage when the actuator 59 is either in the position illustrated in FIGURE 2 or in the position illustrated in FIGURE 5 to prevent overpivoting of the actuator means 59 beyond the counterclockwise position of FIGURE 2 or the clockwise position of FIG- URE 5.

While the switch construction means 20 of this invention has been previously described and illustrated as being a double pole, double throw switch construction means with a complete snap action between the two current carrying positions thereof, it is to be understood that the various parts of this invention can be readily modified to produce other types of switching functions as desired whereby this invention is not to be limited to only the embodiment previously described.

For example, reference is now made to FIGURES 9-11 wherein another switch construction means of this invention is generally indicated by the reference numeral 20A and the parts thereof similar to the parts of the switch construction 20 previously described are indicated by like reference numerals followed by the reference letter A.

As illustrated in FIGURES 9-11, the switch construction means 20A is substantially identical to the switch construction means 20 previously described except that the contact carrying lever means, only lever means 32A being illustrated, are modified to permit the actuator means 59A to be disposed in an intermediate position as illustrated in FIGURE 10 wherein no electrical current can pass through the switch construction means 20A until the actuator means 59A is moved from the inter-mediate position illustrated in FIGURE 10 to either of the operating positions illustrated respectively in FIGURES 9 and 11.

In particular, since the two lever means of the switch construction 20A are identical, the following description of the structure and operation of the lever means 32A also applies to the lever means disposed on the other side of the chamber wall 39A.

The lever 32A has three

arcuate sections

54A, and 55A disposed in series between the opposed ends 35A and 36A thereof with the concave sides of the

arcuate sections

54A, 80 and 55A facing upwardly to be engaged by the respective end 69A of the arm means 68A as will be apparent hereinafter, the intermediate arcuate section 80 being separated from the outboard

arcuate sections

54A and 55A by upwardly facing convex portions 81 and 82 of the lever 32A.

In this manner, the actuator means 59A will have the end 69A of the arm means 68A serially received in the well means 56A, 83 and 57A of the respective

arcuate sections

54A, 80 and 55A as the actuator means 59A is moved and snapped into the positions illustrated respectively by FIGURES 9, 10 and 11.

In particular, with the actuator means 59A disposed in the position illustrated in FIGURE 9, the left hand terminal means 24A is placed in electrical contact with the intermediate terminal means 23A until an operator or the like physically pivots the actuator 59A from the position illustrated in FIGURE 9 to the position illustrated in FIGURE 10. However, as the actuator means 59A is being pivoted in a clockwise direction from the position illustrated in FIGURE 9 toward the position illustrated in FIGURE 10, the end 69A of the arm means 68A rides up the concave cam surface means 54A and when the same crosses beyond the convex point 81 of the lever 32A, the compressive force. and lateral force of the arm 68A causes the lever 32A to snap from the position illustrated in FIGURE 9 to the position illustrated in FIG- URE 10 whereby the end 69A of the arm 68A is fully received in the well 83 of the arcuate portion 80 of the lever 32A to hold the same in the position illustrated in FIG- URE 10 where the intermediate terminal means 23A is electrically disconnected from the right hand terminal means 24A and is not placed into electrical contact with the left hand terminal means 22A until the actuator 59A is further manually pivoted in a clockwise direction to the position illustrated in FIGURE 11.

Thus, it can be seen that the switch construction means 20A cause the lever means 32A thereof to snap between the positions illustrated in FIGURES 9 and 10 and between the positionsof FIGURES 10 and 11 for the purpose previously described while conversely, the lever 32A will snap between the positions of FIGURES 11 and 10 and FIGURES 10 and 9 as the actuator means 59A is moved in a counterclockwise direction.

Another switch construction means of this invention is generally indicated by the reference numeral 20B in FIG- URES 12-14 and parts thereof similar to the switch construction means 20 and 20A previously described will be indicated by like reference numerals followed by the reference letter B.

As illustrated in FIGURES 12-14, the switch construc tion means B is substantially identical to the switch construction 20 previously described except that the lever arms have been modified in such a manner that the same will snap from the position illustrated in FIGURE 12 to the position illustrated in FIGURE 13 in the same manner as the lever arm means 32A previously described for the embodiment of FIGURES 9-11 and will snap from the intermediate position of FIGURE 13 to the position illustrated in FIGURE 14 except that the operator must maintain downward force on the actuator means 59B in the manner illustrated by the arrow 84 in FIGURE 14 to hold the left hand contact 438 into electrical contact with the left hand terminal means 22B. Thus, upon release of the force in the direction of the arrow 84 when the actuator means 59B is in the position illustrated in FIGURE 14, the actuator means 593 will automatically return to intermediate position of FIGURE 13 and snap the left hand contact means 338 out of electrical contact with the left hand terminal means 22B in the manner now to be described.

Since the lever means of the switch construction 20B disposed on the other side of the chamber wall 39B of the housing means 21B is identical to the lever means 32B illustrated in FIGURES 1214, only the structure and operation of the lever means 32B will be hereinafter described with the understanding that the cooperating and non-shown lever means is identical thereto.

As illustrated in FIGURE 12, the lever means 32B is formed with three serially arranged

arcuate sections

55B, 80B and 85 betwen the opposed ends 35B and 36B thereof with the sections 548 and 803 being identical to the

sections

54A and 80 of the lever means 32A of FIG- URE 9.

However, the arcuate section 85 is so constructed and arranged that the same defines a substantially inverted V-shape part having a relatively long angularly disposed cam surface 86 that defines a well 87 just to the left of an upwardly facing convex part 88 adjacent the arcuate section 80B.

In this manner, when the actuator means 59B is pivoted in a clockwise direction from the position illustrated in FIGURE 13 to the position illustrated in FIGURE 14, the end 698 of the arm means 68B will ride out of the well 83B of the intermediate arcuate section 80B and when the same crosses over the point 87 into the well 87 of the arcuate portion 85, the lever means 32B will snap from the position illustrated in FIGURE 13 to the position illustrated in FIGURE 14 except that the actuator means 59B will have to be positively held in the position illustrated in FIGURE 14 because the slope of the cam surface 86 of the lever means 32B is such that the compressive force of the arm means 68B tends to cause the actuator means 59B to be cammed in a counterclockwise direction and force the end means 69B into the well 83B of the intermediate arcuate section 80B as illustrated in FIGURE 13.

Therefore, it can be seen that many of the basic parts of the electrical switch construction means of this invention can be utilized to perform different functions by merely changing the configuration of the contact carrying lever means of the switch construction while still performing the useful function of completely snapping the lever means from one operating position thereof to another operating position thereof without a walking action when the actuator means is disposed in a dead center or null position.

While the form of the invention now preferred has been disclosed as required by the statutes, other forms may be used, all coming within the scope of the claims which follow.

What is claimed is:

1. In combination, a housing means, lever means pivotally carried by said housing means and carrying electrical contact means, fixed electrical contact means carried by said housing means to be cooperable with said lever contact means, and actuator means carried by said housing means and being movable relative thereto, said actuator means having resilient integral arm means hearing against said lever means, said arm means and said actuator means being a one-piece structure and being so constructed and arranged that said arm means pivots said lever means between a contact closed position thereof and a contact open position thereof with substantially a snap action when said actuator means is moved from one position thereof to another position thereof whereby said contact means are placed into and out of electrical contact with each other.

2. A combination as set forth in claim 1 wherein said integral arm means has one end means integrally interconnected to said actuator means and the other end means remote therefrom and bearing against said lever means.

3. A combination as set forth in claim 2 wherein said arm means is arcuately formed between said end means thereof to provide said resiliency thereof.

4. In combination, a housing means, lever means pivotally carried by said housing means and carrying electrical contact means, fixed electrical contact means carried by said housing means to be cooperable with said lever contact means, and actuator means carried by said housing means and being movable relative thereto, said actuator means having resilient integral arm means hearing against said lever means, said arm means and said lever means being so constructed and arranged that said arm means pivots said lever means between a contact closed position thereof and a contact open position thereof with substantially a snap action when said actuator means is moved from one position thereof to another position thereof whereby said contact means are placed into and out of electrical contact with each other, said integral arm means having one end means integrally interconnected to said actuator means and the other end means remote therefrom and bearing against said lever means, said arm means being arcuately formed between said end means thereof to provide said resiliency thereof, said arm means being substantially S-shaped between said end means thereof.

5. A combination as set forth in claim 4 wherein said one end means of said arm means is offset relative to said actuator means and said other end means is centrally aligned therewith.

References Cited UNITED STATES PATENTS 2,027,538 1/1936 Krieger. 3,213,227 10/1965 Heath. 3,225,153 12/1965 Carling. 3,229,062 1/ 1966 Sharples et al. 3,308,260 4/ 1.967 Krieger et al.

FOREIGN PATENTS 54 4,174 1/1956 Belgium.

OTHER REFERENCES Wichmann, Ger. Appl. No. 1,192,289, publ. May 1965, 1 sht. dwg., 2 pp. spec. (copy 200-68).

ROBERT K. SCHAEFER, Primary Examiner.

D. SMITH, JR, Assistant Examiner.