US3475576A - Driving connection for independently mounted circuit breaker and operating handle - Google Patents

Description

Oct. 28, 1969 D. s. BUGNI ET AL I 3, 7 DRIVING CONNECTION FOR INDEPENDENTLY MOUNTED CIRCUIT BREAKER AND OPERATING HANDLE Filed July 20, 1967 2 Sheets-Sheet 1 INVENTOR.

DONALD S. BUGNI KENNETH L. PAAPE zazmavwww Oct. 28, 1969 D. s. BUGNI ET AL 3,475,576

DRIVING CONNECTION FOR INDEPENDENTLY MOUNTED CIRCUIT BREAKER AND OPERATING HANDLE Filed July 20, 1967 2 Sheets-Sheet 2 INVENTOR.

DONALD S. BUGNI KENNETH L. PAAPE United States Patent 0 U.S. Cl. 200172 1 Claim ABSTRACT OF THE DISCLOSURE An operating mechanism for transmitting movements of an operating handle externally mounted on a cabinet to an operating lever of a circuit breaker mounted internally in the cabinet which will permit the circuit breaker to be removed and reinstalled in the cabinet without adjusting the operating mechanism and will drive and resiliently maintain the operating handle against stops in either an OFF or an ON position.

This invention relates to a circuit breaker actuating mechanism and particularly to an operating connection between an operating handle mounted on the front wall of a circuit breaker enclosure and an operating lever of the circuit breaker within the enclosure.

For purposes of illustration, a form of the invention is described herein as applied to a circuit breaker and enclosure combination of the type disclosed in United States Letters Patent No. 3,207,880 of Earl F. Mekelburg, issued Sept. 21, 1965 and entitled Independently Mounted Circuit Breaker and Operating Handle with Driving Connection Therebetween Self-Compensating for Misalignment.

As disclosed in the above identified patent, the enclosure is in the form of a metal cabinet including a rear wall and a front wall which is generally a relatively narrow peripheral flange defining the front opening affording access to the interior of the enclosure. The opening is closed by a hinged door. The control handle for the circuit breaker is mounted on the forward face of the front wall. The train of motion transmitting devices interconnecting the handle and operating lever of the circuit breaker is mounted in the cabinet so that proper interrelations and alignment are readily affected when the circuit breaker is mounted in the enclosure in spaced relation to the side wall, by means of screws or bolts extending through apertures in a detachable panel that is mounted on the rear wall.

While the mechanism as described in the above identified patent overcame the problems encountered during mounting of the breaker on the rear wall, to assure positioning of the breaker accurately in optimum operating position on the rear wall for assuming proper alignment and connection of the devices with the control handle, the mechanism required a complicated slide structure on the front face of the circuit breaker. Further, when the device was placed in service and subjected to environmental vibrations, the operating handle would creep from the ON position to a position intermediate the ON and OFF positions. As cabinets as disclosed in the above identified patent are frequently mounted along traflic aisles, the projecting handle, because of its small size and coloration, was thus positioned to cause injury to personnel and be damaged by equipment moving in the trafiic aisle.

Circuit breaker operating mechanisms for devices known as combination starters and control centers usual- 1y are required to have a means mechanically interlock- 3,475,576 Patented Oct. 28, 1969 ing the operation of the breaker with the door for the cabinet enclosing the circuit breaker so the door cannot be opened when the circuit breaker is in an ON or circuit closing condition. An example of a mechanism for achieving this function is disclosed in United States Letters Patent No. 3,059,072 of Earl F. Mekelburg, issued Oct. 16, 1962 and entitled Dust Proof Switch Enclosure with Switch and Door Interlock. Further, as devices known as circuit breakers are conventionally mounted on panels in a manner to have their operating levers exposed for direct manual manipulation, little attention is exercised during design and manufacture to control the extent of travel of the operating lever and the particular locations whereat the lever causes the components within the circuit breaker to operate to the ON, OFF and RESET conditions. Thus the wide variations in operating characteristics of the circuit breaker levers will be reflected in operation of the externally mounted operating mechanism for the circuit breaker and the interlocking mechanism for the cabinet door.

When circuit breakers are used in combination starter enclosures, commercial practice dictates that the mechanism interconnecting the external operating handle and the circuit breaker operating lever be arranged so that the panel on which the circuit breaker and the electromagnetically operated switching device are mounted may be removed and reinstalled in the cabinet without loss of adjustment of the operating mechanism in spite of the fact that the panel may be reinstalled in the cabinet in a position slightly displaced from the original position. Further, as only a minor amount of adjustment is provided by the clearance between the mounting screws and the mounting holes in the circuit breaker, and as the operating mechanism must be capable of moving the circuit breaker lever to the ON and the OFF positions, as well as from the TRIPPED to the RESET position after the circuit breaker has tripped in response to an excess current flow, the operating mechanism between the external operating handle and the circuit breaker lever is required to compensate for wide variation in circuit breaker travel without loss of operation when the circuit breaker is removed and reinstalled in the cabinet.

It is an object of the present invention to provide an inexpensive, rugged operating mechanism for transmitting movements of a handle externally mounted on a cabinet to an operating lever of a circuit breaker mounted within the cabinet and to arrange the mechanism so the circuit breaker may be easily removed and reinstalled in the cabinet without adjustment or change in operation of the operating mechanism.

A further object is to provide an operating mechanism to transmit movements of a handle mounted externally on an enclosure front to the operating lever of a circuit breaker mounted internally in the enclosure and to arrange the mechanism so the handle will be maintained against fixed stops in either of two positions when the enclosure is subjected to vibration and to maintain the operability of the mechanism without adjustment thereto when the circuit breaker is removed and reinstalled in the enclosure.

Another object is to provide an operating mechanism to transmit movements of a handle externally mounted on an enclosure front to operating lever for a circuit breaker mounted internally in the enclosure, said mechanism including a rotatable lever and a compression spring which overcomes the spring bias of the circuit breaker lever and positively moves the operating handle to a full OFF or RESET position when the breaker is in a tripped condition and wherein an operating connection between the operating mechanism and the circuit breaker operating lever is arranged so the circuit breaker 3 can be removed and reinstalled in the enclosure without readjusting the operating mechanism.

An additional object is to provide an operating mechanism to transmit movements of a handle externally mounted on a front wall of an enclosure to an operating lever of a circuit breaker that is mounted on an internal rear wall of the enclosure and to provide the mechanism with a means including a toggle-acting compression spring which will overpower any spring bias on the operating lever and positively drive the handle against stops to either of two positions and a detachable connection between the operating mechanism and the operating lever to permit the circuit breaker to be removed and reinstalled in a slightly displaced position in the enclosure without impairing the operability of the mechanism to transmit said movements.

Another object is to provide an operating mechanism to transmit movements of a handle externally mounted on a front wall of an enclosure to an operating lever of a circuit breaker that is mounted on an internal rear wall of the enclosure and to provide the mechanism with a means including a toggle acting compression spring which will overpower any spring bias on the operating lever and positively drive the handle against a pair of spaced stops which define the ON and the OFF positions of the handle and to provide an adjustable connection between the operating lever and the operating mechanism which may be secured in an adjusted position to compensate for variations in the location and the operating characteristics of the operating lever and Will assure that the connection will be operative to move the operating lever to the OFF position when the handle is moved to the OFF position and the securement for the connection is inoperative to maintain the connection in the adjusted position.

Another object is to transmit movements of a handle externally mounted on a front wall of an enclosure to an operating lever of a circuit breaker that is mounted on an internal rear wall of the enclosure with a mechanism having two separable assemblies with one of the assemblies including a toggle acting compression spring which is operated by the handle and will overpower any spring bias on the operating lever and positively drive the handle against a pair of spaced stops which define the ON and the OFF positions of the handle and to provide a detachable lost motion connection between the assembly mechanism which is operated by the handle and a mechanism that operates the circuit breaker lever to permit the circuit breaker to be removed and reinstalled in a slightly different location in the enclosure without impairing the operability of the mechanism to transmit said movements.

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

FIG. 1 is a front elevational view of a dust proof circuit breaker enclosure with the door open to show a circuit breaker therein and one form of an operating mechanism according to the present invention with the external operating handle on the enclosure in the OFF position.

FIG. 2 is a fragmentary view of the circuit breaker in FIG. 1 with portions of the enclosure removed to illustrate a connection between an assembly which is actuated by the external handle and an assembly which actuates the circuit breaker operating lever.

FIG. 3 is a fragmentary bottom view of the structure illustrated in FIG. 1 and is taken on line 33 in FIG. 1.

FIG. 4 is a side view of the operating mechanism for the circuit breaker in FIG. 1 with the circuit breaker in an OFF and RESET condition.

FIG. 5 is a side view of a modified form of the operating mechanism for the circuit breaker in FIG. 1 with the circuit breaker in an OFF and RESET condition.

FIG. 6 is a side view of the operating mechanism for the circuit breaker in FIG. 5 with the circuit breaker in an ON condition.

FIGS. 7 and 8 are front and bottom views of the operating mechanism for the circuit breaker shown in FIG. 5.

Referring to the drawings, and as more fully described in the above identified patent Mekelburg 3,207,880, the enclosure comprises a metal cabinet, indicated generally as 10, which has a rear wall 11 on which a circuit breaker 12 is mounted, side walls 13, a top wall 14 and bottom wall 15, and a marginal front wall 16. The front wall 16 is in the form of a peripheral flange defining an opening 17 affording access to the interior of the cabinet. The opening 17 may be closed by a suitable hinge-mounted door 18 swingable about a vertical axis to open and closed positions. The door 18 carries suitable latching devices 19, operated by a handle mechanism 20, by which it can be secured firmly in closed position.

Various defeater mechanisms, not shown but disclosed in the above entitled Mekelburg Patent 3,059,072, may be provided and must be operated to permit opening of the door when the circuit breaker is closed.

An operating handle 21 is pivotally supported on a suitable housing 23 on the forward face of the front wall 16, for swinging about the pivot axis parallel to the rear wall 11 to ON, OFF and RESET positions, selectively. The handle 21 is shown in FIG. 4, in a down position, which is in the OFF and RESET or open position of the circuit breaker 12. In the raised or ON position of the handle 21, as in FIG. 6, the circuit breaker 12 is closed.

The present invention is concerned principally with a mot1on transmitting train of devices drivingly connecting a self included operating lever 24 of the circuit breaker 12 and the operating handle 21 on the front wall margin 16 of the enclosure 10.

The circuit breaker 12 may be secured to a panel 25 which, in turn, is secured by suitable screws 26, or the like, to the rear wall 11 of the enclosure 10 as shown in FIGS. 1-4, or may be directly secured to a rear wall 11 of a cabinet 10a, as shown in FIGS. 5-8.

The circuit breaker 12 is a conventional one manufactured for general use in this and other types of installatrons, and as shown, is of the type disclosed in the application of James H. Leonard and William H. Woods, No. 561,456, filed June, 29, 1966. The breaker 12 has stationary and movable contacts, not shown, and includes the operating lever 24 which is spring biased to move with a snap action as it swings about a horizontal axis on a pivot parallel to the rear wall 11 to a lower, or OFF position, in which it moves the movable contacts to a circuit opening position, and to an upper or ON position, n which it moves the movable contacts to a circuit closmg position. Snap acting spring means, not shown, in the breaker 12 drive the handle operating lever 24 with a snap action to the ON and OFF-RESET positions, selectively, when the lever 24 is moved manually a predetermined distance part way toward the selected positions, respectively. The lever 24 is moved from the ON to an intermediate TRIPPED position by the breaker mechanism when the breaker 12 is tripped by overload and the like.

As disclosed in the Mekelburg Patent 3,059,072, a link 27 is pivotally connected at one end to the operating handle 21 by a pivot which is eccentric to the pivot of the handle 21. Consequently, upon swinging the handle 21 upwardly, the link 27 is moved inwardly from the position shown in FIG. 5 and slightly upwardly relative an axis perpendicular to the rear wall 11 to the position shown in FIG. 6. The link 27 has an enlarged inner end portion 28 to which a lever or link 29 is connected. In the form illustrated this is accomplished by providing a pair of passages through the portion 28 and by providing a pair of ears 30 on the lever 29 which are received through the passages and held in place by a suitable cotter pin 31. An operating mechanism 32 for transmitting movements of the link 27, which is moved in response to movements of the handle 21, will now be described. The operating mechanism 32 includes a relatively rigid mounting plate 33, a bell crank lever 34, the link or lever 29, a compression spring mechanism 35, and a means for detachably interconnecting an arm of the lever 34 to the operating lever 24 of the circuit breaker 12.

As shown in FIGS. 3 and 4, the mounting plate 33 has a flange .38 along a marginal edge secured on an inner surface of the 'front wall 16 by screws 39 which extend through suitable openings in the front wall 16 and are threaded into the housing 23 to thereby maintain the mounting plate 33 and the housing 23 for the handle 21 in proper relative positions on the front wall 16, with the mounting plate 33 extending spaced and parallel to one of the side walls 13 and perpendicular to the rear wall 11. The flange 38 has an opening, not shown, aligned with a suitable opening in the front wall to provide a passage for the link 27. The bell crank lever 34 has a pair of arms 40 and 41 extending from a pivot .42. The pivot 42 is supported by the mounting plate 33 and extends parallel to the rear wall 11 to space the bell crank lever 34 from the mounting plate 33. The arms 40 and 41 extend substantially at right angles to each other and are movable about the pivot 42 in a plane parallel to the mounting plate 33. The lever 29 has an enlarged end portion 43, pivotally connected to a free end portion of the lever 40, by a pivot pin 45. The pivot pin 45 axially extends parallel to the rear wall 11 and transmits the movements of the lever 29 to the bell crank lever 34. a

The compression spring mechanism 35 includes a compression spring 46, a lower pivot member 47, an upper pivot member 48, a bracket 49 and a pivot pin 50. The pivot pin 50 is secured to the enlarged end portion 43 of lever 29 to extend along an axis perpendicular to the mounting plate 33. The lower pivot member 47 has a bore receiving the pivot pin 50 and has a surface 51 providing a seat for the lower end of the spring 46 and includes a stem portion 52 extending upwardly through the openings provided by the convolutions of the compression spring 46 and through a suitable bore in the upper pivot member 48. The pivot member 48 is formed to have a pair of oppositely extending bosses 53, which acts as pivots. One of the bosses 53 is received in a vertically extending notch 54 in the mounting plate 33 and the other boss 53 is received in a vertically extending notch 55 formed in a bight portion of the bracket member 49. The bracket member 49 has a pair of ears secured to the mounting portion, 33 to provide a space wherein the pivot member 48 is received. As shown, the bosses 53 and the notches 54 and 55 provide a pivot for the member 48 that extends on an axis perpendicular to the mounting plate 33. Further, as shown in FIG. 5, the pivot pin 50 is located to position the pivot member 47 in a location between the front wall 16 and an axis through the pivots 53 and 42 when the handle is in the lowered, or OFF, position, so that the spring mechanism 35 constantly urges the lever 29 toward the front wall 16 and the handle 21 into tight engagement with a stop 56 on the housing 23 when the lever 21 is in the OFF position. When the handle 21 is raised to the upper ON position, as in FIG. 6, the pivot 50 will be located between the rear wall and the axis through the pivots 53 and 42. Thus the spring mechanism 35 will constantly urge the lever 21 into engagement with a stop 57 when the lever 21 is in the ON position. The force of the compression spring 35, maintaining the handle 21 against stops 56 and 57, is selected to exceed the force supplied by the spring bias on the lever 24 so that the handle 21 will be positively maintained against the stops 56 and 57 in either of the positions shown in FIGS. 4 and 6.

As shown in FIGS. 1-4, a means 58 for interconnecting the arm 41 of the bell crank lever 34 and the lever 24 includes a U-shaped support 59 and a U-shaped operating lever 60. The support 58 has a mounting portion 61 secured between a rear wall of the circuit breaker 12 and the mounting panel 25 by screws 62 which extend through suitable slightly elongated bores in the breaker 12 and elongated openings, not shown, in the mounting portion 61. The screws 62 are tightened into suitable threaded openings in the panel 25 so the panel 25, the breaker 12, and the interconnecting means 58 are removable as a unit assembly from the enclosure 10 when screws 26 are removed, The U-shaped support 59 is formed with integral arm portions 63 and 64 extending perpendicular to the panel 25 and parallel to the opposite side walls of the breaker 12. The arms 63 and 64 provide a support for pivot pins 65 and 66 which extend in a common axis parallel to the rear wall 11. The U- shaped operating lever has a pair of arm portions 67 and 68 extending perpendicular to a bight portion 69. The arm portions 67 and 68 are pivotally connected to pivot pins and 66 so the bight portion 69 is movable in an arcuate path across the front face of the breaker 12. The bight portion 69 has a rectangular shaped opening 70 therein which receives the operating lever 24 with clearance. The arm portion 68 has an opening 71 therein which receives a finger 72 formed on the arm 41. The finger 72 extends perpendicular to the mounting plate 33. The finger 72 and opening 71 are sized to provide a lost motion connection between the bell crank lever 34 and the operating lever '65 to permit removal of the assembly including the panel 25, the breaker 12, and the connecting means 58 from the enclosure by removing the screws 26 and moving the panel 25 to the left in FIG. 1 to a position whereat the finger 72 is withdrawn from the opening 71 so that the assembly including the panel 25 may be withdrawn from the enclosure 10 without dis turbing the operating mechanism 32. Thus when the as sembly, including the panel 25, is reinstalled in the enclosure 10, all that is required is to position the panel 25 on the rear wall 11 and to move the panel to the right, as in FIG. 1, to a position wherein the finger 72 is received within the opening 71. When the screws 26 are secured in suitable threaded openings in the rear wall 11, the assembly, including the panel 25, will be properly positioned without further adjustment within the enclosure 10 to cause operation of the lever 25 upon movement of the handle 21 to the ON and OFF positions selectively. During the initial assembly of the circuit breaker 12, and the support 59 on the panel 25, the elongated openings in the circuit breaker 12 and the support 59 permit the relative positions of the circuit breaker 12 and the operating lever 60 to be adjusted relative to the finger 72 to cause proper operation of the lever 24 upon movement of the handle 26.

As was previously described, the bell crank lever 34 is rotated in response to movements of the handle 21 to the OFF and ON positions. When the lever 34 rotates, the finger 72 within the opening 71 causes the operating lever 60 to rotate. The rotation of the lever 60 through the opening 70 imparts a corresponding movement to the lever 24 to move the lever 24 to the OFF and ON positions in response to the movements of the handle 21 to the ON and OFF positions. The lost motion connection provided by the finger 72 in opening 71 and the clearance between the walls of the opening 70 and the lever 24 are arranged so that when the handle 21 is in the ON position and the circuit breaker 12 is subject to an overload condition which causes the lever 24 to move from the ON position to a TRIPPED position which is intermediate the ON and OFF positions, the lever 24 will be free to move to the TRIPPED position while the handle 21 is maintained in tight engagement with the stop 57. When it is desired to reset the breaker all that is required is to move the handle 21 from the ON position to the full OFF-RESET position whereat the internal mechanism within the breaker 12 is reset so as to cause normal operation of the circuit breaker.

When the operating mechanism according to the present invention is employed with a circuit breaker that is not to be removed from the enclosure or separated from its operating mechanism during wiring of the enclosure, the embodiment shown in FIGS. -8 may be used. In the embodiment shown in FIGS. 5-8 components providing functions similar to the functions achieved by the components described in FIGS. 1-4 are provided with the designations used to describe the embodiment in FIGS. 1-4. The embodiment shown in FIGS. 5-8 is particularly suited for use in control center structures which are formed to have individual cubicles wherein an enclosure supporting the circuit breaker and the circuit breaker operating mechanism is inserted and closed by a door hinged on the control center structure, As shown in FIGS. 5-8, an enclosure a which is supported in a control center structure includes a rear wall 11 and a side wall 12 to which the mounting plate 33 is secured by screws 73. The enclosure 10a does not include a front wall corresponding to the front wall 16 in FIGS. 1-4 as a door 74 ofthe control center structure is provided with a suitable opening 75 which receives the operating handle mechanism 21 and its housing 23. The opening 75 is closed by a closure plate 76 that is fastened to the flange 38 by the screws 39 which also secure the housing 23' to the flange 38.

The operating mechanism 32 which transmits the movements of the link 27 to the bell crank lever 34 is identical to the mechanism 32 described in connection with FIGS. 1-4. The means 77 interconnecting the bell crank lever 34 and the operating lever 24 includes a finger portion 78 on the arm 41 and a member 79. The member 79 has a bifurcated end 80 embracing opposite sides of the lever 24 and is pivotally mounted on the finger 78 by a pivot pin 81. The member 79 is adjustably positioned on the finger by a screw 82 which permits the position of the member 79 to be adjusted to compensate for variations in travel of the lever 24. The foregoing is accomplished by elongating the opening in member 79 through which the screw 82 extends as it is threaded into a suitable opening in the finger 78. It is to be appreciated that in the event the screw 82 should become detached from the finger 78, the member 79 would be free to rotate about the pin '81 and if the handle 21 is in the ON position and was moved to the OFF position the motion of the handle 21 would not be transmitted to the operating lever 24 of the circuit breaker 12 so that the operating handle 21 would be in the OFF position while the lever 24 of the circuit breaker 12 was in the ON position. This dangerous and objectionable condition is precluded by a projection or a pin 84 which extends from the finger 78 into an enlarged opening 85 in the member 79. The pin 84 and opening 85 are arranged so that as the finger 78 is moved downwardly in response to the movements of the handle 21 to the OFF position the top edge of the pin 84 will engage the upper edge of the opening 85 and assure movement of the lever 24 to the OFF position, Further, the pin 84 and the opening 85 are sized and arranged so that movement of the handle 21 to the ON position will not cause a corresponding movement of the lever 24 to the ON position. Thus the mechanism is arranged to assure that the circuit breaker 12 may be moved to a circuit opening condition in event of failure of the screw 82 to maintain the adjustment between the finger 7-8 and the member 79 to cause proper operation of the operating mechanism for the circuit breaker 12.

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 claim.

What is claimed is:

1. In combination, a cabinet having a rear wall, a side wall portion, and a front wall portion in spaced alignment with the rear wall, a mounting support detachably secured to said rear wall, a circuit breaker secured to said mounting support in spaced relation to said side wall portion, said circuit breaker including an operating lever pivotally mounted for rotation about an axis parallel to the rear wall and spring biased for movement with a snap action to ON and OFF positions respectively to open and close the circuit breaker when the operating lever is moved through a position that is intermediate the ON and OFF positions by a force exceeding the spring bias on the lever, said operating lever being additionally movable from the 'OFF position about said axis to a TRIPPE'D position which is intermediate said ON and said OFF positions and to an OFF-RESET position that is located so that OFF position is intermediate the TRIPPED position and the OFF-RESET position, a pair of spaced parallel support arms extending perpendicularly from said mounting support adjacent to the opposite side walls of said breaker, a U-shaped member having a bight portion and a pair of arms extending perpendicularly therefrom, means pivotally mounting said arms of said U-shaped member respectively to said first mentioned arms, said bight portion having an opening therein receiving said operating lever for moving the operating lever to the ON and OFF-RESET positions as the arms of the U-shaped member is swung about its pivotal mounting -on said support arms; an operating mechanism mounted adjacent to said side wall portion, said mechanism including an operating handle extending externally of said front wall portion and movable between extremes comprising ON and OFF positions, a crank pivoted about an axis in substantial alignment with the pivotal mounting of said U-shaped member, means interconnecting said operating handle and said crank, said means including a toggle spring for supplying a force for resiliently maintaining the handle respectively in said ON and OFF positions,- and a finger on said crank extending perpendicular to said side wall portion into an oversize opening on one of said arms of said U-shaped member for lost motion engagement therewith whereby movement of the circuit breaker in response to electrical overload conditions from the ON to the TRIPPED position is ineffective to cause movement of said operating handle whereas movement of said operating handle between ON and OFF positions is effective to move said operating lever between its respective ON and OFF- RESET positions, said lost motion further permitting removal of the assembly comprising the mounting support, the breaker, the support arms, and the U-shaped member from the cabinet as a unit without regard to precise alignment with said operating mechanism after the mounting support is detached from the rear wall and while the unit is moved to a position wherein said finger is withdrawn from said lost motion engagement in the opening in said arm of said U-shaped member.

References Cited UNITED STATES PATENTS 1,677,692 7/ 1928 Stokes.

2,418,006 3 1947 Bangert.

3,229,056 1/ 1966 Turnbull 200-50 3,272,953 9/1966 Tillson 200172 ROBERT K. SCHAEFE'R, Primary Examiner ROBERT A. VANDERHYE, Assistant Examiner US. Cl. X.R.

Images