US3175063A - Dual contact circuit closing arrangement - Google Patents

Description

March 23, 1965 c. R. RHODES DUAL. CONTACT CIRCUIT CLOSING ARRANGEMENT 2 Sheets-Sheet 1 Filed Aug. 21, 1962 IN VENTOR. Uhesfer R Rhodes Arrys March 23, 1965 C. R. RHODES DUAL CONTACT CIRCUIT CLOSING ARRANGEMENT Filed Aug. 21, 1962 2 Sheets-Sheet 2 INVENTOR.

C'hesfer A. Rhodes United States Patent 3,175,063 DUAL C IItNTACT CIRCUIT CLOSING ARRANGEli IENT Chester R. Rhodes, Whittier, Calih, assignor to Hurletron, incorporated, Danville, 1th, a corporation of Delaware Filed Aug. 21, 1%2, Ser. No. 218,370 4 Claims. ((11. 200-404) This invention relates generally to electrical switching apparatus, and more particularly, to improvements in a rotary type electrical relay of the character described having a plurality of like roller contact members each provided with a pair of different contact surface diameters movable over a multiple-level, electrical contact header plate in response to signal actuated movements of an armature in a magnetic field.

The electrical switching relay with which this invention is concerned is used advantageously in the field of instrumentation and in other electronic fields where multiple switching of electiical energies must be accomplished under the control of low level signals. Generally, such swiching relays comp-rise electromagnetic devices which provide for selective, pivotal movement of an armature to decrease the reluctance of a magnetic circuit of normally high reluctance according to well-known principles. When the electric current through the winding or coil wound upon the magnetic core of the device is cut off, a magnetomotive force no longer is applied to the armature, so that the armature will be returned to a so-called high reluctance position relative to the pole pieces of the device. The return movement of the armature can be effected by suitable restoring means, such as, a spring. The pivotal movement of the armature in the magnetic field can be used advantageously to open or close an electrical circuit by operating a switch having contacts which are engaged or disengaged, as the case may be, by suitable contacts movable with the armature. Such rotary relay switching devices are characterized in their many uses by their relatively small size and ability to develop high torque over relatively small angular distances traversed by the armature in its movement in the magnetic field.

A primary consideration in the successful employment of such rotary type relays is the efficient and effective translation of the armature with respect to the contacts of the switch or switches to be actuated. The armature rnust be rapidly responsive to low applied torques accurately to open and close electrical circuits with a relatively small amount of are over which the armature is moved. It is desirable to minimize the adverse effects of frictional forces to which the armature is subjected during the making and breaking of switching contacts.

Another important consideration is the elimination of adverse effects of pitted, scored and worn switching contacts likely to be encountered after sustained, normal use of the rotary relay. Such structural defects increase the frictional forces applied to the pivotal armature and, accordingly, reduce the efiiciency and accuracy of operation of the relay.

Still another consideration is economy of manufacture of the rotary relay while still enabling the relay to achieve the foregoing advantages, as well as others hereinafter mentioned.

Accordingly, it is a major object of the invention to provide a rotary type relay of the character described which is characterized by a construction capable of achieving the foregoing as well as other advantages of construction and operation.

A primary object of the invention is to provide a rotary relay of the character described in which novel conductive roller contact members are mounted for movement with the armature or other movable carrier member, and,

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in which a novel insulating header plate or support having selectively located, fixed electrical contacts is employed, the roller contact members being movable over the fixed contacts with substantially reduced friction for electrical switching functions.

Another important object of the invention is to provide a rotary relay as described in which said roller contact members comprise a plurality of like dumb-bell-shaped roller members rotatable on opposite end portions of different transverse diameters and said header plate or support has electrical contacts embedded therein flush with the upper surface of said support and arranged in a pair of concentric circles of different radii, each circle of contacts being axially offset relative to the other in parallel planes, the opposite end portions, respectively, of the said roller member being movable over one of said circles of contacts.

Another important object of the invention is to provide a rotary relay of the character described in which means are provided for spring-loading each roller member into engagement with said insulator member carrying said fixed contacts for varying the amount of the load applied to the roller contact member for important adjustment advantages when required.

Other important objects of the invention include provision of novel mounting means for said roller contacts to achieve self-alignment thereof; novel restoring means for returning the armature to a high reluctance position when current to the coil is cut-0E; and a construction for a rotary relay of the character described characterized by a construction which enables economical manufacture and assembly of the component parts thereof and which is durable.

The foregoing and other advantages will become apparent from the following detailed description of a preferred embodiment of the invention and illustration thereof in the accompanying drawings. Minor variations in the size, arrangement, construction and proportion of the several parts thereof may occur to the skilled artisan without departing from the scope or sacrificing any of the advantages of the invention.

In the drawings:

FIG. 1 is a fragmentary, side elevational view of the rotary relay embodying the invention with portions broken away to show details of structure.

FIG. 2 is a top plan view of said relay showing the novel restoring means for returning the armature to a high reluctance position.

FIG. 3 is a fragmentary elevational view illustrating an armature having a configuration alternative to that shown in FIG. 1.

FIG. 4 is a sectional view taken through said relay along the line 44 of FIG. 1 and in the general direction indicated.

FIG. 5 is a sectional view taken through said relay along the line 55 of FIG. 1 and in the general direction indicated.

FIG. 6 is a fragmentary median sectional view taken longitudinally through said relay.

Generally, the invention is directed to achieving the enumerated advantages by means of novel structure embodied in the electrical contact portion of the relay. In relays of the rotary type, there are two main groups of electrical contacts, namely, a group of contacts which remain stationary and a group of contacts which are movable or rotatable with a rotary carrier member, such as, an armature. The herein invention provides novel roller contact members, each of generally dumb-bell configuration, mounted for movement with the armature under the influence of an electrical field established by an applied signal. Each roller contact has two end roller portions of dilferent diameter arranged to move respectively over concentric arrays of two groups of fixed electrical contacts with movement of the armature. The fixed electrical contacts are mounted in the surface of an insulating header plate or support which has a general step configuration providing a pair of parallel levels or surfaces axially offset one relative to the other. The central insulating plate portion is so axially offset somewhat above the peripheral plate portion. The fixed contacts are arranged in concentric circles of different radii on the respective surfaces of the two insulator plate portions to provide an inner circular array and an outer circular array of spaced apart, fixed contacts, one on each of the two levels. Each roller contact member is arranged to have one of its end roller portions ride on one of said levels or surfaces and over said contacts as the carrier member or armature is pivoted. The use of such roller contacts having end roller portions of different contact surface diameter which roll over the two circular arrays of fixed contacts reduces sliding friction to an immaterial Value. In addition, means are provided for spring-loading the roller contact members and for selectively varying the bias or load applied to the roller contact members to compensate for wear of the electrical contacts and over-travel of the roller contact members.

Referring now to the drawings, the rotary relay embodying the invention is identified generally by the reference character in PEG. 1. For purposes of description, strict dimensional relationships between certain of the well known electrical components of such a relay 10 have not been maintained or illustrated because they may vary in form within a wide range without departing from the principles of the herein invention. The relay 10 has an annular base header plate 12, the upper surface of which is of generally step configuration. Thus, plate 12 has a central portion 16 which is raised or axially offset r upwardly relative to the portion 1 surrounding the central portion 12. The header plate 12 is formed of a suitable electrical insulating material or may be formed as a composite member. For instance, a layer of glass cemented to a base disc or a ceramic material fired to such a disc may be utilized to provide the upper, stepped insulating surface of the header plate 12. The upper surfaces of the portions 14 and 16 are fiat and parallel.

Each of said stepped portions or levels 14 and 16 has a circular array of fixed electrical contacts embedded flush in the upper surface thereof. These contacts, advantageously, are constructed of silver. The outer array 22 is embedded in the peripheral header plate portions 14 and the inner array 24 is embedded in the central plate portion 16. Individual contact members of the two arrays are respectively connected in serial circuit with an operating mechanism 4%. This mechanism is any one of many such selectively operated mechanisms well known in the art, for example, a telephone control office switching arrangement. r

A shaft member 52 is centrally fixed to the header plate 12, both to the raised central plate portion and to the integral peripheral plate portion in common. A cylindrical electromagnetic winding 34 is mounted on the shaft 32, concentrically with base plate 12. The electromagnetic winding 34 is controllably supplied with energizing power from an appropriate signal source 42 by Way of leads 43. Both of these last two elements are illustrated schematically. Such signal sources may take a near limitless number of forms, well known in the art, for supplying signals of alternate polarity.

Plural pole pieces 36, constructed of ferromagnetic material, for example, of soft iron, are fixedly disposed in pairs about the periphery of the winding 34. The pairs of pole pieces are connected together physically and magnetically by end plates 37, and a highly permeable core member within the winding. This core member is not shown in FIG. 1 for purposes of clarity. The core member is, however, seen in FIG. 6. The end plates 37 and the winding 34 are staked to this core member so d that, structurally, all constitute a single unit. As illustrated, in a first direction from left to right, the magnetic reluctance of the gap between two pole pieces of the pair 36 increases markedly. The importance of this increase of reluctance becomes more clear hereafter in a consideration of the operation of this structure.

The winding 34 and pole pieces 36 are fixedly mounted to shaft 32. A lower portion 38 of this shaft fits into a central recessed portion of a contact insulating plate 44. This latter plate 44 is mounted for rotation about the shaft 32 by means of a miniature ball bearing 35.

An armature is fixed on the upper surface of this rotatable plate 44. This armature comprises three ferromagnetic vertical members 47, an armature plate 46 and an armature bracket plate 51. Opposite ends of these vertical members are fixed to the armature plate 46 and the bracket plate 51, as by rivets 49. The armature plate is fixed to the contact insulating plate 44- by screws 48 and the bracket plate is journalled for rotation about shaft 32 by a bushing 135. Thus, the armature is freely rotatable about this shaft.

In the operation of the elements described, a magnetizing current flows by way of leads 43 from the signal source 42 to cylindrical winding 34 to generate a magnetic flux in the pole pieces 36. Considering only the left hand pole piece pair shown and the right hand ferromagnetic member 4 7, it is clear that the magnetic reluctance in the path between these two pole pieces of the illustrated left hand pair is decreased if a ferromagnetic member, the right hand member 47, be moved from right to left to overlay the most proximate portions of the illustrated pair of pole pieces 36. Accordingly, passage of current through the winding 34 from the signal source 42, urges the right band member 47 to move to the left in accordance with the laws of conservation of energy. Similar urgings are imposed on the other two vertical armature members by the other pairs of pole pieces 36, only one of which other pairs is shown specifically. Since the ferromagnetic members 47 are fixedly mounted to the armature plate by rivets 49, application of signal current from the source 42 causes rotation of the rotatably mounted armature about the shaft 32.

Binding stud 53 and stop pin 39 are both fixed in the upper portion of winding 34 and are positioned to project upward within a bracket plate slot. Thus the stud 53 and pin 39 limit rotational motion of the bracket and, consequently, of the armature in two directions.

Thus the armature, and with it, the contact insulating plate, is urged to move between two limited positions by signals applied to the winding 34. Plural contact support members 61 are mounted about the lower surface of the insulating plate by screws 63. Hence, these support members are fixed to and rotate with the armature.

These support members 61 are constructed for retaining, respectively, fine silver contact roller members 70. These contact roller members comprise first and second end roller portions '72 and 74 connected by a shaft portion '73. Projecting beyond each end portion is an axle stub member for retention within the support member slotted portions 62. Thus the members 70 are retained man orientation generally perpendicular to the shaft 32.

Opposite roller member end portions 72 and 74- have contacting surface radii proportioned to the distance these end portions are positioned from the center of shaft 32 and differing in transverse radius by the thickness of the plate central portion 16. Thus the contact shaft portion is disposed parallel to surfaces of plate portions 14 and 16.

Generally U-configured wire contact spring members 76 are, respectively, fixed at either end to a support member by screws 6? and are bent such that the cross portion of the U-spring bears against each roller member shaft portion 73. Thus this spring urges the roller member end portions against a respectively associated one of the contact arrays 22 and 24. By virtue of the surface radii of the contacting roller member end portions, these roller end portions rotate smoothly in contact with the surfaces of header plate portions 14 and 16 as the armature assembly rotates the insulating plate 44. Ready adjustment of the contact pressure of these roller end portions is simply decomplished by bending the springs 76.

In FIG. 2 the structure of FIG. 1 is seen in plan view in some particularly pertinent aspects. The three vertical ferromagnetic armature members 47 are shown fixed to the armature bracket plate 51 by rivets 49. This bracket plate 51 comprises a slotted portion 52 for cooperative action with the stud member 53 and the stop pin 39 as seen heretofore.

A restoring spring member 54 is fixed to a wall of the bracket plate 51 for urging the stud 53 against the left band edge of the slotted portion of the bracket plate, as illustrated. The stop pin 39, conversely, is backed against the right hand edge of the slotted portion 52 of the bracket plate to limit motion of that bracket plate and the associated armature in a clockwise direction.

It will be recalled that movement of the armature causes movement of the insulating plate 44 and, consequently, of the plural roller members 70. Now this movement of the armature governs establishment of conduction paths between the associated contacts of the two concentric arrays 22 and 24. Therefore, in accordance, with the invention, the two stop members, stud 53 and pin 39, are spaced apart in correspondence with the spacing between the contacts of the two concentric arrays.

Looking next to FIG. 3 there is seen a partially sectioned elevation view of a pole piece arrangement alternative to and, in a sense, complementary to the pole piece arrangement 36 shown in FIG. 1. In this FIG. 3 similarly numbered elements have functions similar to those of FIG. 1. Other elements not shown in this FIG. 3 correspond in structure and function to such items illustrated in FIG. 1.

This important difference between these two structures exists. Pole piece pair members 136 slope from left to right toward a closer vertical relation. This relation is opposite to that illustrated in FIG. 1 where the pole piece members step from right to left toward this closer vertical relationship. Similarly, the relationship of stud 153 and pin 139 is interchanged from left to right with the relationship of stud 53 and pin 39 in FIG. 1. This merely adds to the fact that the armature member 47 moves from left to right upon application of magnetizing signals to the arrangement shown partially in FIG. 3. Clearly, in this modified embodiment of the invention, spring member 54 and signal source 42 are reversely connected.

Next, in FIG. 6 there is seen in partially sectioned view, an elevational arrangement of the winding 34, illustrated in FIG. 1, together with associated detailed structural elements.

In this partially sectioned, detailed elevation view of FIG. 6 there is shown a ferromagnetic core portion 81 of the shaft 32. This core portion 81 is fixed in the shaft 32 by two threaded members 103. These two members, respectively, constitute an upper portion of shaft 32 and engage a lower shaft portion 35. The shaft, in turn, is seen to be rotatable relative to insulating plate 44 within the bushing 135 which is attached fixedly to the bracket plate.

The core member 81 is magnetically connected in circuit with the pole pieces 36, not shown here, by way of the soft iron ferromagnetic connecting plates 37. These plates, the winding 34, and the core member 81 are all staked together by stake 132. Thus there is established a complete magnetic circuit save for the gap between the pole piece members considered in connection of FIG. 1. The shaft 32, in turn, is fixedly connected to the header plate 12 by an upset soft metal rivet member 107 as shown.

The upper shoulder of the shaft portion 38 is shown bearing rotatably against a bearing surface within the insulating plate 44. This bearing surface is associated with ball bearing 35 considered heretofore.

Similar arrangements are seen associated with similarly numbered structural elements at the upper end of shaft 32. It is to be noted that the shaft 32, as noted above, is relatively rotatable. In an absolute sense, in this embodiment of the invention, the shaft is fixed to the header plate 12 by the upset soft metal rivet portion 107. Rotation of other elements noted is about this shaft.

FIG. 4 shows a transverse section of the switching apparatus illustrated in FIG. 1. This FIG. 4 shows this structure in plan view looking upwardly from the outer and inner contact arrays 22 and 24, noted heretofore, as indicated by section lines 44.

Here the contact insulating plate 44 is seen. This insulating plate comprises elongated mounting holes 148 for receiving screws 48 for fixing this insulating plate to the armature plate 46. These screws are received by correspondingly tapped holes in the armature plate 46. The elongated holes 148 are provided to enable rotational adjustment of the contact insulating plate 44. These elongated holes allow the entire roller contact arrangement to be adjusted in relation to plate 46 in correspondence with the relative positions of contacts of the two arrays 22 and 24.

Also shown in FIG. 4 are the pairs of mounting screws 69 by which the generally U-configured wire springs 76 are retained against the bracket 61. Only an illustrative one of these screws is shown in FIGURE 1 for simplicity of illustration. It will be recalled from the discussion of FIG. 1, that these springs 76 maintain each of the plural contact roller members 70 in position by bearing respectively against shaft portions 73 of these roller members.

Looking next to FIG. 5, here is shown, in plan view, the section 55 of the structure of FIG. 1. In this plan view the inner and outer contact arrays 24 and 22, respectively, are disposed concentrically with the raised central portion 16 of the plate 12 and the peripheral portion 14 of this same plate 12.

A typical roller contact member 70 is shown in phantom view in two alternative roller positions. These two positions correspond, respectively, to positioning of the armature bracket 51 against stud 53 and pin 39. By inspection it is clear that in these alternative positions the phantom roller establishes electrical contact between the illustrated inner array contact and, alternatively, between the two illustrated outer contacts. Clearly, rotary movement of the armature between positions established by the edge portions of the armature bracket slot 152 simultaneously establishes alternative circuit conditions between plural leads associated with the output circuit connections, to the operating circuit 40 shown in FIG. 1.

These alternative conditions are established with certainty as the plural, silvered roller contact members in accordance with the invention are oscillated along the circular paths defined by the two contact arrays 22 and 24.

The coordinated diameters of the inner and outer roller end portions make for certainty of contact and avoid sliding friction of the roller contact end portions with the cooperative fixed contact members embedded in the base header plate 12.

All of this multiple circuit control is readily accomplished in accordance with the invention by binary signals from the source 42. These may take many, many forms well known in the art. These signals, as discussed above, act to drive the armature rotatably between alternatively contacting positions in cooperation with the restoring spring 54.

The invention has been set forth hereinabove only in an illustrative embodiment. Clearly the difierentially ended roller contact elements in accordance with the invention lend themselves readily to many advantageous employments in rotary switching structures as will be clear to those skilled in the art.

What it is desired to secure by Letters Patent of the United States is:

l. A rotary switching arrangement which comprises a header plate having a centrally disposed, raised portion, and a peripheral portion, said plate being constructed of insulating material, a first array of contacts circularly disposed planarly in the surface of said base plate central portion, a second array of contacts circularly disposed planarly in the upper surface of said peripheral plate portion in concentric relation with said first array, a rotatable insulated carrier member mounted for rotation about an axis coincident with the centers of said arrays, a plurality of contact support members mounted on said carrier member for rotation therewith, a like plurality of conductive roller contact members mounted, respectively, in the contact support members of said plurality for rotation about an axis perpendicular to said carrier member axis, the roller members of said plurality extending longitudinally in correspondence with the dirference of radius between said contact arrays, said roller members, further, comprising first and second end portions having, respectively, first and second roller surface radii of curvature, said first radius being less than said second radius by an amount corresponding to the raising of said central plate portion from said peripheral plate portion, and said roller members being oriented in said frame members for positioning said first roller end portion proximate said first array and said second roller end portion proximate said second array, both said last named roller end portions being respectively positioned in peripherally contacting, rolling relation with said planarly disposed arrays.

2. A rotary switch which comprises a roller contact member of conductive material, said member having a first circular end portion having a first diameter, and a second oppositely disposed circular end portion having a second greater diameter, a first array of fixed contact members planarly disposed along a first circular arc, a second array of fixed contact members planarly disposed along a circular arc of radius greater than the radius of'said first arc, concentrically with said first array, means for mounting said contact member for rolling about a first axis of symmetry while said axis of symmetry also rotates about a second axis normal thereto, and said second axis defining the center of said arcs, said means being disposed for bringing said first roller contact end portion in rolling contacting relation with said first arc, and for bringing said second roller contact end portion in rolling contact with said second arc of contact disposition, said first and second arrays defining first and second planes respectively, and the planes being parallel one to the other, said first axis defining a third plane during rolling which is parallel to the planes of the arrays, but with the first plane spaced between the second and third planes.

3. A rotary switch which comprises, a header plate con structed of insulating material, said plate having a central elevated surface and a parallel peripheral surface, a first array of contact members circularly disposed planarly in said central surface, a second array of contact members planarly disposed in said peripheral surface concentrically with said first array, a rotatable armature mounted concentrically with said arrays, a conductive roller member mounted for rotation about a longitudinal axis perpendicular to the concentric axis of said arrays, said roller member having a first circular end portion of a first transverse diameter and a second circular longitudinally opposite end portion having a second transverse diameter greater than said first transverse diameter, said roller member being connected to said armature for rotation therewith above the concentric mounting of said armature and said roller member end portions being disposed respectively for peripheral rolling contact with said contact arrays, said roller member having a length corresponding to the distance between said first and second arrays and having said first and second circular end portions disposed, respectively, in rolling contacting relation with said central surface and said peripheral surface.

4. A rotary switch which comprises an insulating header plate having a first, elevated central portion and a second peripheral portion, said plate portions having first and second parallel surfaces displaced by a fixed amount, a first array of contact members planarly disposed circularly in said central plate portion surface and a second contact array being planarly and circularly disposed in said peripheral plate surface concentrically with said first array, a plurality of conductive roller members disposed radially of the concentric axis of said arrays, said roller members being mounted for rotation about an axis corresponding to said radius of disposition, said rollers further extending between the circles of disposition of said arrays and being mounted for peripheral rolling contact with said contact arrays, said roller members, further, having a first end portion of circular transverse cross section disposed in peripheral contacting relation with said first array and a second longitudinally opposite end portion of circular transverse cross section having a radius greater than the radius of said first portion by said fixed amount, the said end portions being disposed in peripheral rolling contact with said arrays, about said concentric axis, each in rolling contact with contacts of said arrays and means for rotating said plurality of rollers, thereby to establish conduction paths between contact members of said first and second arrays.

References Cited by the Examiner UNITED STATES PATENTS 1,229,266 6/ 17 Hillhouse 200-8 1,806,117 5/31 Petersen 200-166 1,935,498 11/33 Bently 200-166 2,418,616 4/ 47 Batcheller 200-166 2,482,997 9/49 Andersson 200-11 2,818,479 12/57 Volk 200-166 2,916,584 12/59 Molyneux 200-87 BERNARD A. GILHEANY, Primary Examiner.

ROBERT K. SCHAEFER, Examiner.

Claims (1)

1. A ROTARY SWITCHING ARRANGEMENT WHICH COMPRISES A HEADER PLATE HAVING A CENTRALLY DISPOSED, RAISED PORTION, AND A PERIPHERAL PORTION, SAID PLATE BEING CONSTRUCTED OF INSULATING MATERIAL, A FIRST ARRAY OF CONTACTS CIRCULARLY DISPOSED PLANARLY IN THE SURFACE OF SAID BASE PLATE CENTRAL PORTION, A SECOND ARRAY OF CONTACTS CIRCULARLY DISPOSED PLANARLY IN THE UPPER SURFACE OF SAID PERIPHERAL PLATE PORTION IN CONCENTRIC RELATION WITH SAID FIRST ARRAY, A ROTATABLE INSULATED CARRIER MEMBER MOUNTED FOR ROTATION ABOUT AN AXIS COINCIDENT WITH THE CENTERS OF SAID ARRAYS, A PLURALITY OF CONTACT SUPPORT MEMBERS MOUNTED ON SAID CARRIER MEMBER FOR ROTATION THEREWITH, A LIKE PLURALITY OF CONDUCTIVE ROLLER CONTACT MEMBERS MOUNTED, RESPECTIVELY, IN THE CONTACT SUPPORT MEMBERS OF SAID PLURALITY FOR ROTATION ABOUT AN AXIS PERPENDICULAR TO SAID CARRIER MEMBER AXIS, THE ROLLER MEMBERS OF SAID PLURALITY EXTENDING LONGITUDIANLLY IN CORRESPONDENCE WITH THE DIFFERENCE OF RADIUS BETWEEN SAID CONTACT ARRAYS, SAID ROLLER MEMBERS, FURTHER, COMPRISING FIRST AND SECOND END PORTIONS HAVING, RESPECTIVELY, FIRST AND SECOND ROLLER SURFACE RADII OF CURVATURE, SAID FIRST RADIUS BEING LESS THAN SAID SECOND RADIUM BY AN AMOUNT CORRESPONDING TO THE RAISING OF SAID CENTRAL PLATE PORTION FROM SAID PERIPHERAL PLATE PORTION, AND SAID ROLLER MEMBERS BEING ORIENTED IN SAID FRAME MEMBERS FOR POSITIONING SAID FIRST ROLLER END PORTION PROXIMATE SAID FIRST ARRAY AND SAID SECOND ROLLER END PORTION PROXIMATE SAID SECOND ARRAY, BOTH SAID LAST NAMED ROLLER END PORTIONS BEING RESPECTIVELY POSITIONED IN PERIPHERALLY CONTACTING, ROLLING RELATION WITH SAID PLANARLY DISPOSED ARRAYS.

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