US3325690A - Control device and attachment - Google Patents

Description

1967 2. J. KRUZIC ETAL CONTROL DEVICE AND ATTACHMENT 2 Sheets-Sheet 1 Filed Oct. 15, 1965 @329 %-i32 FIG.6. I125 l NVENTORS Zelko J. Kruzic 8 John H. Mullen WITN ESSES ATTOR NEY United States Patent Ofiice 3,325,690 Patented June 13, 1967 5,325,650 QONTRQL DEVICE AND ATTACHMENT Zellro .1. Krnzic, Daugherty Township, New Brighton, and

John H. Muilen, Brighton Township, Beaver, Pa.. as-

signers to Westinghouse Electric Corporation, Pittshurgh. 1%., a corporation of Pennsylvania Fiied Get. 13, 1965, Ser. No. 495,616 16 Claims. (Ci. 3117-99) This invention relates generally to electric control structures and more particularly to electric control structures of the type comprising a control device and an attachment device for removable connection to the control device.

In the art of electric control, it is desirable to provide for quick connection and disconnection of an attachment to a control device. For example, in control panels it is often desirable to provide for easy mounting and dismounting of a latch device or time delay device on a relay or contactor.

Accordingly, an object of this invention is to provide an electric control structure comprising a control device and an attachment device with improved means for removably connecting the attachment device to the control device.

Another object of this invention is to provide an improved control structure comprising a control device and an attachment device with improved means for removably mounting the attachment device on the control device without the use of tools.

Another object of this invention is to provide an improved electric control structure comprising a control device and an attachment device with connecting means that can be removably mounted in position to connect the attachment device to the control device when the control device is mounted in a close side-by-side relationship with other control devices on a control panel.

The novel features that are considered characteristic of the invention are set forth in particular in the appended claims. The invention itself, however, both as to structure and operation, together with additional objects and advantages thereof, will be best understood from the following detailed descrpition when read in conjunction with the accompanying drawings.

In said drawings:

FIGURE 1 is a sectional view of a control structure constructed in accordance with principles of this invention;

FIG. 2 is a perspective view of the mounting plates seen in FIG. 1;

FIG. 3 is a perspective view of a connecting member seen partially in full lines and partially in broken lines in FIG. 1;

FIG. 4 is an exploded end view, with parts broken away, of the control structure seen in FIG. 1 with a connecting member being shown that does not appear in FIG. 1; and

FIG. 5 is an end view, with parts broken away, of the parts disclosed in FIG. 4 in the connected position.

FIGURE 6 is a view similar to FIGURE 3 of another connecting member.

Referring to the drawings, there is shown in FIG. 1 an electric control structure 5 comprising a. control device or electromagnetic relay device 7 and an attachment device 9. The control device or electromagnetic relay device 7 comprises a control apparatus or electromagnetic relay 11 and a mounting plate 13. The control apparatus or electromagnetic relay 11 is a relay that is described in more detail in the patent to Gustav Iakel, Patent No. 3,088,058, issued Apr. 30, 1963. The attachment device 9, which may be a latch device, a time delay device or other type of attachment, is disclosed in this case as a latch device that is more specifically described in the patent of Zelk-o J. Kruzic, Patent No. 3,201,545 issued Aug. 17, 1965.

The relay 11 comprises a housing comprising a base 1 and a cover 15 both of insulating material. The housing parts 14 and 15 are held firmly together as a unit by means of bolts (not shown). An E-shaped main magnet or core member 17 is supported, with its legs extending up- Wardly, in the housing base 13. A magnetizing winding, or coil 19, which is disposed on a suitable spool 21 of insulating material, is positioned over the middle leg of the core member 17. An E-shaped armature 25 is provided to cooperate with the core member 17. The armature 25 is connected to an insulating contact carrier 27 by means of a pin 29 that pivotally mounts the armature 25 on the contact carrier 27 for limited pivotal movement about the pin 29 in the plane of the paper as seen in FIG. 1.

The relay 11 is a multi-pole relay with only one pole unit being seen in FIG. 1. Each pole unit comprises two stationary contact structures 31 each of which has a solderless terminal connector 33 disposed at its outer end and a stationary contact 35 disposed at its inner end. In each pole unit, a bridging contact structure 39, having a contact 41 at each of its two opposite ends, is provided to bridge the associated stationary contacts 35. The bridging contact structure 59 is supported on the contact carrier 27 in an opening 43, and it is maintained in position by means of a spring 45. The spring 45 positions the bridging contact structure 39 and also acts to permit movement of the bridging contact structure 35 upon contact engagement to thereby provide that the contacts will mate properly when they are closed. The contacts 35, 41 are normally open contacts although they are shown in FIG. 1 in the closed position. It is to be understood that the contacts can be made normally open or normally closed, in a man ner well known in the art, depending upon the particular control requirements. The insulating contact carrier 27 comprises two upstanding connecting parts 47 (FIGS. 1, 4 and 5 that protrude out through the front of the housing cover 15 through an opening 49 in the front of the cover 15. Suitable springs (not shown) are provided to bias the contact carrier 27 away from the closed position seen in FIG. 1 to thereby provide for an opening operation of the relay 11 in a manner to be hereinafter described.

The disclosed attachment device 9 is a latch mechanism that comprises an insulating base 51 and an insulating cover 53 that is suitably secured to the base 51 to form a housing. An energizing coil 57 is supported on an insulating spool 59 that is in turn supported on an insulating member 61 that is suitably secured on shoulder portions of the housing base 51. Solderless terminal connectors 63 are provided to enable connection of the coil 57 in an electric circuit. The latch device 9 also comprises a generally tubular core member 65 that is suitably supported, partially within the coil 57 and spool 59, in the housing 51, 53. A movable core member or armature 67, which is generally tubular in shape and which is disposed partially within the coil 57 and spool 59, is provided to cooperate with the stationary core 65. A spring 69 biases the movable core member 67 downward to the lower position shown in FIG. 1. A generally tubular insulating latch carrier 71, having a lower end 73 and an upper end 75, is disposed generally within the tubular stationary core member 65 and movable tubular armature 67. The latch carrier 71 is a tubular insulating member. Two rigid metallic latch arms 77 are pivotally supported on the latch carrier 71 by means of a pin 79, and they are spring biased in opposite directions by means of a torsion spring 81. Suitable slots are provided in opposite sides of the latch carrier 71 to permit movement of the latch arms 77 to the latching and unlatching position in a manner to be hereinafter described. The latch carrier 71 is biased downward by means of a spring 83. The upper or front end 75 of the latch carrier 71 protrudes out through a suitable opening in the front of the cover 53.

As is seen in FIG. 1, when the latch device 9 is mounted on the relay 11 the lower part 73 of the latch carrier 71 engages the front part 47 of the contact carrier 2'7.

The parts of the electric control structure are shown in the lower latched position in FIG. 1, in which position the contacts 35, 41 are closed. The latch carrier 71 is latched in the lower position by means of the latch arms 77 that are biased away from each other to engage the lower part of the core member 65. Because of the engagement of the lower part 73 of the latch carrier with the upper part 47 of the contact carrier 27, the contact carrier 27 and the core member 25 of the relay 11 are held in the lower latched closed position shown in FIG. 1.

When it is desired to unlatch the latch mechanism 9 to operate the relay 11 to the open position, the coil 57 of the latch mechanism 9 is energized, whereupon the movable core 67 is attracted upward against the bias of the spring 69 to engage the latch arms 77 to force the latch arms to pivot toward each other out of engagement with the lower part of the stationary core member 65 to an unlatching position. When the latch arms 77 are moved to the unlatching position, springs (not shown) of the relay 11 move the contact carrier 27 and latch carrier 71 upward compressing the spring 33. Thereafter, the springs (not shown) of the relay 11 will maintain the armature 25, contact carrier 27, and latch carrier 71 in the upper position, in which position the contacts 41, 35 are open, until the relay 11 is operated. The coil 57 is energized only momentarily to effect an opening operation, and, when the coil is deenergized, the spring 69 returns the movable core 67 to the lower position seen in FIG. 1.

The relay 11 is closed by energization of the coil 19, whereupon the armature 25 is pulled down to the position seen in FIG. 1 moving the contact carrier 27 and the bridging contact 39 downward to the closed position seen in FIG. 1. As the contact carrier 27 is moved downward the upper part 47 thereof moves away from the part 73 of the latch carrier 71, whereupon the spring 83 expands causing the latch carrier 71 to follow the contact carrier 27 down to the closed position. As the latch carrier 71 reaches the position wherein the latch arms 77 clear the lower end of the stationary core member 65 the torsion spring 81 forces the arms 77 outward to the latching position seen in FIG. 1 to latch the latch carrier 71 and, therefore, the contact carrier 27 and armature 25 in the lower closed circuit position. Thus, even though energization of the coil 19 is momentary to effect a closing operation, the relay will be latched in the closed circuit position until the coil 57 is again energized to unlatch the latch mecha nism 9 or until the latch mechanism is unlatched manually.

Improved means is provided for removably connecting the attachment or latch device 9 to the control device 7. The control device 7 comprises the relay 11 and the metallic rigid mounting plate 13. As can be seen in FIG. 2, the mounting plate 13 is formed with two ledge parts 87 each of which is provided with a tapped opening 89 for receiving a mounting screw 91 (FIG. The two screws 91 serve to secure the relay 11 to the mounting plate 13. The mounting plate 13 is formed with two bentover hook parts 93. The insulating housing 51, 53 of the latch device 9 is generally square in front elevational dimension, and a flat supporting part 95, that extends around the back end of the base 51 of the housing 51, 53, rests on a shoulder 97 of the cover 15 of the relay housing 14, 15 to support the latch device 9 on the relay 11. A small overhang 99 formed integral with the base of the relay housing 51, 53 extends around the back four sides of the base 51 adjacent to the supporting part 95 to provide additional support against rocking movement of the relay 9 when the relay is in the mounted position. With the relay housing down in the fully mounted position wherein the support part 95 rests on the shoulder 97 of 4 the part 15 of the relay housing, and with the overhang 99 extending around the generally square perimeter 109 of the front part of the relay housing part 15, when the latch device 9 is held down in the position seen in FIG. 1, the latch device 9 is securely mounted and supported on the relay 11.

Referring to FIGS. 15, two connecting members 191 are provided to enable removable connection of the latch device 9 to the control device 7. Each of the connecting members 191 comprises a rigid metallic member comprising an elongated flat leg part 103 that is bent-over at the upper or front end thereof to form a short downwardly extending leg part 105. An opening 107 is formed in the back or lower part of the elongated leg 103. As is disclosed in FIG. 4, the housing parts 51, 53 of the latch device 9 are provided with opening means therein that cooperate to form two cavities or compartments 107. During the assembly of the latch device 9, before the cover 53 is placed into position, two springs 109 are placed in the two cavities 107, and thereafter the cover 53 is brought down into the position seen in FIG. 4- and suitably secured in place to capture the compression springs 199 in place in their associated cavities 107. A separate slot 111 is provided over each of the cavities 107 with each of the slots 111 being formed large enough to receive the part 195 of one of the connecting member 101 and small enough that the housing will engage the associated compression spring 109 to limit outward movement of the spring 1119. As can be seen in FIG. 2, the hook parts 93 of the mounting plate 13 are diagonally positioned on opposite sides of the mounting plate 13. As was previously mentioned, the latch device housing 51, 53 is generally square in front-elevational view and the cavities 197 are positioned diagonally on opposite sides of the housing 51, 53 in proximity to the two diagonal corners of the front of the housing 51, 53.

When it is desired to mount the latch device 9 on the control device 7, the latch device 9 is moved to the position seen in FIGS. 1 and 5 with the support parts 95, 99 of the device housing 51, 53 cooperating with the support parts 97, 169 of the relay housing part 15 to support the latch device 9 on the relay 11. Thereafter, the two connecting members 101 are moved into the mounted position seen in FIG. 5 to secure the latch device 9 on the control device 7. The connecting members 101 are both connected in position in the same manner. A connecting member is moved into a position wherein the part thereof can be moved into the slot 111 of the latch device housing 51, 53. The connecting member is then pressed downward moving the part 105 into the slot charging the associated compression spring 109 and moving the back or lower part of the member 101 down to a position wherein the opening 107 thereof can receive the hook 93. The connecting member 101 is thereafter rocked slightly toward the relay to position the hook 93 in the opening 167, and the connecting member is thereafter released whereupon the associated spring 109 biases the connecting member upward such that the cooperating interengaging parts, comprising parts, comprising the hook 93 and lower end of the opening 197, engage to maintain the connecting member in place. Since the associated spring 109 is charged when the lower part of the connecting member 191 is hooked in position as seen in FIG. 5, the biasing force of the charged spring 199 biases the latch device 9 down to the mounted position seen in FIG. 5. The biasing force of the charged spring 1119 also operates to bias the connecting member upward. to the engaged mounted position seen in FIG. 5. Both of the connecting members 101 are moved into the mounted position in the same manner hereinbefore set forth with regard to the one connecting member. As was previously set forth, the connecting members 101 are positioned in proximity to the diagonal corners of the front of the latch device 9 at the opposite sides of the control struc ture 5 to removably secure the latch device to the control I device. When it is desired to remove the latch device 9 from the control device 7, the connecting members 101 are merely pressed downward against the bias of the springs 109 until the openings 107 are positioned to clear the hooks 93, and thereafter the connecting members are rocked to move the lower end parts thereof outward free of the hook members 93 whereupon the connecting members 101 may be lifted outward clear of the control struc ture.

Referring to FIG. 6, there is disclosed therein a connecting member 115 comprising an elongated first leg 117 bent-over at the front part thereof to form a downwardly extending short leg 119. The long leg 117 of the connecting member 115 is provided with three openings 121, 123, and 125 at the lower end thereof. The leg 117 of the member 115 is scored at 127 and 129 to provide two break-off parts 131and 132. The relay 11 disclosed in FIG. 1 is a four-pole relay with the common contact carrier 27 carrying four bridging contact members 39 of the four pole units. The relay 11 may be constructed as an eight pole relay with four similar poles disposed over the four poles hereinbefore described and with all of the bridging contact members operated by a common contact carrier 27. In this case, since the relay 11 would be a structure having a greater height, the lower part 132 of the connecting member 115 can be broken off at 12.9 and the opening 123 would receive the hook 93 (FIG. 2) when the connecting member 115 is mounted in position to secure the latch device 9 to the eight pole relay. The relay 11 may also be a twelve pole relay with three fourpole tiers. In this case, the connecting member 115 would be used as shown in FIG. 6 with the lower opening 125 being used to receive the associated hook 93 of the mounting plate 13. When the relay is a four pole relay as shown in FIG. 1, the part 131 is bro-ken off at 127 (FIG. 6) to provide a connecting member like the connecting member 101 of FIG. 3.

From the foregoing, it will be understood that there is provided by this invention an improved electric control structure comprising an electric control device and an attachment device removably connected to the control device. The attachment device is operatively connected to the control device merely by means of the mounting operation of the attachment device to the control device. The latch device, control device and connecting member 'are'constructed such that the members can be removably connected together in the field Without the use of tools. The connection is quick-detachable so that a worker can readily change attachment devices when desired at the installation. The attachment device, control device and connecting members are constructed such that little pane-l space is required for the connection whereby the conncction can be readily made even when the control device is mounted on a panel in a close side-by-side relationship With other control devices. Although a latch device has been specifically described as the attachment device that is secured to the control device, it is to be understood that a time delay or other attachment device could be similarly removably connected to the control device.

While the invention has been disclosed in accordance with the provisions of the patent statutes, it is to be understood that various changes in the structural details and device on said relay device with the back of said attachment device being adjacent the front of said relay device, biasing means captured in place on said attachment device biasing said connecting member in a direction from back to front, said connecting member and said relay device comprising cooperating interengaging parts maintained in interengagement by said biasing action of said biasing means whereby said biasing action of said biasing means maintains said connecting member in place to thereby maintain said attachment device on said relay device.

2. An electric control structure comprising an electromagnetic relay device having a back and a front, an attachment device having a back and a front, means comprising a connecting member mounting said attachment device on said relay device with the back of said attachment device being adjacent the front of said relay device, biasing means on said attachment device biasing said connecting member in a direction from back to front, said connecting member and said relay device comprising cooperating interengaging parts maintained in interengagement by said biasing action of said biasing means whereby said biasing action of said biasing means maintains said connecting member in place, said biasing means being charged between said connecting member and said attachment device to thereby bias said attachment device toward said relay device to the connected position.

3. An electric control structure comprising an electromagnetic relay device having a back and a front and an attachment device having a back and a front, means comprising a pair of connecting members mounting said attac-hment device in a mounted position on said relay device with the back of said attachment device being adjacent the front of said relay device, cooperating interengaging parts between each of said connecting members and said relay device, biasing means in a charged condition between said connecting members and said attachment device to bias said connecting members in a direction from back to front to mounted connecting positions wherein said cooperating interengaging parts are in interengagement and to bias said attachment device from front to back into the mounted position on said relay device, means on said attachment device cooperating with said biasing means and with said cooperating interengaging parts to maintain said connecting members in said mounted connecting positions, and said connecting members beig removable from said mounted connecting positions after an initial movement from front to back against the force of said biasing means and after an additional movement to disengage said cooperating interengaging parts.

4. An electric control structure constructed in accordance with claim 2 wherein said biasing means is captured in place on said attachment device.

5. An electric control structure comprising a control device having a back and a front, an attachment device having a back and a front, said control device comprising a control apparatus and a mounting plate, means mounting said control apparatus at the back thereof on said mounting plate, said mounting plate comprising a hook part, resilient means captured in place on said attachment device, an elongated connecting member comprising a first elongated leg part having an opening at the back end thereof and being benbover at the front end thereof to provide a short leg part spaced from and generally parallel to said elongated leg part, said attachment device comprising an enclosed cavity and a compression spring captured in place in said cavity, said attachment device having a slot therein to provide access to said cavity, said connecting member being positioned with said short leg part extending through said slot into said cavity in a position charging said compression spring and being positioned with said hook part protruding through said opening whereby the force of said compression spring biases said connecting member in a direction from back to front on said control structure to engage said hook part in said opening to limit the movement of said connecting memher in said direction from back to front to thereby maintain said spring in said charged condition whereby the force of said charged spring biases said attachment device in a direction from the front toward the back of said control structure, and said connecting member being removable without the use of a tool by movement thereof in a direction from front to back against the bias of said spring and by an additional movement to release said connecting member from said hook part.

6. An electric control structure comprising a control device having a back and a front, a latch device having a back and a front, said control device comprising an electromagnetic relay and a mounting plate and means securing said relay to said mounting plate, said relay comprising an insulating housing and a relay mechanism supported on said insulating housing, said latch device comprising an insulating housing and a latch mechanism supported on said insulating housing, said insulating housing of said latch device having a cavity therein and an opening in the front thereof leading into said cavity, resilient means disposed in said cavity, an elongated connecting member comprising a back end and a front end, said connecting member being mounted on said latch device and mounting plate to connect said latch device with said control device, said front end of said connecting member comprising a part passing through said opening in the front of said latch device insulating housing into engagement with said resilient means in a position wherein said resilient means is in a charged condition with said back end of said connecting member comprising a part in interengagement with a part of said mounting plate to limit movement of said connecting member in a direction from back to front under the force of said resilient means whereby said parts that are in interengagement limit movement of said connecting member to thereby maintain said resilient means in said charged condition in which charged condition said resilient means biases said latch device in a direction from front to back into a mounted position on said control device.

7. A control structure constructed in accordance with claim 6, said parts that are in interengagement comprise a hook part on said mounting plate and an opening in said connecting member.

8. A control structure constructed in accordance with claim 6, said insulating housing of said latch device and said insulating housing of said relay comprising cooperating mating parts mating to provide increased stability of said latch device on said control device.

9. An electric control structure having a back and front, said control structure comprising a control device having a back and a front and an attachment device having a back and a front, said control device comprising a control apparatus having a back and a front and a mounting plate, means securing said control apparatus at the back thereof on said mounting plate, said control apparatus comprising an insulating housing and a control mechanism supported on said insulating housing, said attachment device comprising an insulating housing and an attachment mechanism supported on said insulating housing, said mounting plate comprising first interlocking means disposed at opposite sides of said mounting plate, said attachment device having cavity means therein, resilient means supported in said cavity means, said insulating housing of said attachment device having slot means therein at the front thereof to provide access to said cavity means, a pair of connecting members, each of said connecting members comprising an elongated leg part having a second interlocking means at the back end thereof and being bent over at the front end thereof to form a short leg part disposed generally parallel to the long leg part thereof, said connecting members being in the connecting position with said second interlocking means being in interengagement with said first interlocking means and with the short leg parts thereof being disposed in said slot means such that said resilient means biases said connecting members in a direction from back to front to engage said second interlocking means in said interengagement with said first interlocking means whereby said resilient means biases said attachment device from front to back into the mounted position on said control device.

It). A control structure constructed in accordance with claim 9, said insulating housing of said control apparatus and said insulating housing of said attachment device comprising mating parts mating to provide increased stability of said attachment device on said control device.

111. A control structure constructed in accordance with claim It said first interlocking means comprising hook means on said mounting plate and said second interlocking means comprising opening means in said connecting members for receiving said hook means.

12. A control structure constructed in accordance with claim 10, said attachment device being operatively connected to said control device merely by the mounting of said attachment device on said control device.

13. An electric control structure comprising a control device having a back and a front, a latch device having a back and a front, mounting means mounting said latch device at the back thereof on the front of said control device,

said control device comprising a back plate, an electromagnetic relay and means securing said electromagnetic relay to said back plate,

said electromagnetic relay comprising a first insulating housing and a relay mechanism supported on said first insulating housing,

said latch device comprising a second insulating housing and a latch mechanism supported on said second insulating housing, said relay and said latch device comprising cooperating parts cooperating such that upon operation of said relay to an operated position said latch device will automatically latch said relay in said operated position, said mounting means comprising an elongated connecting member having a first interlocking part at the back thereof, said back plate comprising a second interlocking part, resilient means supported on said latch device, said connecting member comprising a front part for cooperating with said resilient means,

said latch device being mounted on said control device with said resilient means engaging said front part of said connecting member to bias said connecting member frontward and with said first interlocking part of said connecting member being in interlocking engagement with said second interlocking part of said mounting plate to limit frontward movement of said connecting member whereby the biasing force of said resilient means biases said second insulating housing backward into a supported position on said first insulating housing, and said connecting member being removable by the application of a backward force against the bias of said resilient means and by a movement moving said first interlocking part of said connecting member from said interlocking engagement with said second interlocking part of said mounting plate to thereby permit removal of said latch device from said control device.

14. An electric control structure according to claim 13, said second interlocking part comprising a hook-shaped part on said mounting plate and said first interlocking part comprising opening means in said connecting member for receiving said hook-shaped part in interlocking engagement.

15. An electric control structure according to claim 14, said mounting means comprising a pair of said connecting members, a pair of said hook shaped parts on said mounting plate, said resilient means comprising a pair of spring members supported on said latch device, and each connecting member of said pair of connecting members cooperating with one of said hook-shaped parts of said mounting plate and with one of said spring members according to claim 14. I

9 10 16. An electric control structure according to claim References Cited iiviiiil tfi isulafing Z Ffh lO 33E1 UNITED STATES PATENTS erem an a separa e openi e r n of leading into each of said cavities, each of said spring $088058 4/1963 Jake] 317 195 members being captured in a diiferent place in one of said 5 3,209,102 9/1965 Boley 317*187 X cavities, and each of said connecting members comprising 3,215,800 11/1965 Hurter at 200 104 a .part at the front thereof extending into one of said openings in the front of said insulating housing to engage ROBERT SCHAEFER Pnmary Examiner one of said spring members. M. GINSBURG, Assistant Examiner.

Claims (1)

1. AN ELECTRIC CONTROL STRUCTIRE COMPRISING AN ELECTROMAGNETIC RELAY HAVING A BACK AND A FRONT, AN ATTACHMENT DEVICE HAVING A BACK AND FRONT, MEANS COMPRISING A CONNECTING MEMBER MOUNTING SAID ATTACHMENT DEVICE ON SAID RELAY DEVICE WITH THE BACK OF SAID ATTACHMENT DEVICE BEING ADJACENT THE FRONT OF SAID RELAY DEVICE, BIASING MEANS CAPTURED IN PLACE ON SAID ATTACHMENT DEVICE BIASING SAID CONNECTING MEMBER IN A DIRECTION FROM BACK TO FRONT, SAID CONNECTING MEMBER AND SAID RELAY DEVICE COMPRISING COOPERATING INTERENGAGING PARTS MAINTAINED IN INTERENGAGEMENT BY SAID BIASING ACTION OF SAID BIASING MEANS WHEREBY SAID BIASING ACTION OF SAID BIASING MEANS MAINTAINS SAID CONNECTING MEMBER IN PLACE TO THEREBY MAINTAIN SAID ATTACHMENT DEVICE ON SAID RELAY DEVICE.

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