US1979824A - Switch - Google Patents

Description

NOV. 1934- c. CHRISTENSEN ET AL SWITCH Filed Jan. 27, 1.923 4 heets-Sheet l 1934 c. CHRISTENSEN ET AL.

SWITCH 1923 4 Sheets-Sheet 2 Filed Jan. 27

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SWITCH Fil ed Jan. 27, 1923 4 Sheets-Sheet 5 AW nu 1N1 Milk Nov. 6, 1934.

c. CHRISTENSEN ET AL 1,979,824

SWITCH Filed Jan, 27, 1923 4 Sheets-Sheet 4 260 LAT/0N .5. 252

fkyer Patented Nov. 6, 1934 UNITED STATES PATENT OFFICE SWITCH Christen Christensen and Alwin G. Steinmayer, Chicago, Ill., assignors to Electrical Engineers Equipment 00., Chicago, 111., a corporation of Illinois This invention relates to electrical power transmission, and more specifically to an improved switch for use in such transmission, and control means therefor.

One object of the invention is to provide an improved switch especially suitable for high tension work.

Another object is to provide an improved arrangement of the supporting tower and the leads from the transmission cable to the switch.

Another object is to provide a floating blade type of switch embodying the principle of actuation by a movable insulator.

Another object is to provide a movable insulator switch having no live linkage.

Another object is to provide a movable insulator switch having no mechanical linkage except that necessary to move the insulator.

Another object is to provide a movable insulator switch having no linkage except a pivotal mounting for the movable insulator, and means for actuating the insulator.

Another object is to provide a movable insulator switch having a flexible permanent connection for the terminals carried by the movable insulator.

Another object is to provide an air-break switch interrupting the circuit at one point only, in which the movable contact-making terminal is mounted rigidly on a movable insulator.

Another object is to provide a simplified remote control mechanism for switches.

Another object is to provide for step by step actuation of a motor without the use of solenoids.

Another object is to control the stopping movement of the mechanical parts by electrical contacts actuated by the parts themselves.

Another object is to provide unitary and improved signaling and control means for switch operating mechanism controlled from a remote point.

Another object is to alternately open and close the switch by actuation of a motor always in the same direction.

Another object is to provide a selective interlock so that actuation of the remote control means to move the switch into the position it is already occupying can neither cause any damage nor actuate the switch.

Another object is to provide emergency means for manual operation of such a switch.

Another object is to provide automatic stop means for stopping the parts in proper position when manually operated.

Another object is to provide a switch in which the current flows through only one set of surfaces having sliding contact with each other.

Another object is to provide for the operation of switches of very large size by a motor of unusually small size in comparison to the work it has to perform.

Another object is to provide two means of adjustment in series for the automatically controlled parts, of which one adjustment may be completely made in the shop, and the other in the field without disturbing the first adjustment.

Another object is to determine the closed po sition of the moving contact blades by the linkage actuating them, rather than by a stop.

Another object is to provide for precise adjustment of the contact elements of the switch after the installation is complete. These last two features are paricularly advantageous in installations of very large size, in which the movable insulator is of dimensions comparable with the body of a grown man.

Further objects and advantages of the invention will become apparent as the description proceeds.

in the accompanying drawings, Figure l is an end View of our switch mounted on its tower and connected to its operating mechanism;

Figure 2 is a plan view of the motor and transmission parts;

Figure 3 a fragmentary sectional View taken along the line 3-3 of Figure 2;

Figure 4 an end elevation of the motor and transmission parts associated therewith;

Figure 5 is a wiring diagram;

Figure 6 is a section on line 6--6 of Figure 2; and

Figure I is a detail of a modification.

Tower and leads In the embodiment of the invention selected for illustration, tower 10 is suitably mounted, as on concrete base 12, and carries lateral arms 14 supporting insulators 16 upon which the main transmission cables may be strung. The installation illustrated is part of a three phase system, and is accordingly provided with leads 13, 20 and 22, leading down from each of the three cables. Obviously, such leads can be associated with the main cables at their ends or at intermediate points along their lengths.

Lower arm structures 24 are mounted on tower 10 below arms 14 to carry longitudinal supports 26 supporting a plurality of spaced individual switch devices, one for each cable. The switch dev ces are spaced from the tower far enough 110 for most convenient connection to the central lead 20, and leads 18 and 22 curve out and in respectively to bring their ends into the same plane as lead 20, but spaced from it longitudinally.

The switch is of a construction such as is illustrated in our copending application, Serial No. 317,350, now Patent No. 1,935,111, issued November 14, 1933, which is a division of the present application, and to which reference may be had for a more complete description of the switch. For the present discussion it is sufiicient to state that each of the three switching units includes a stationary insulator 38 mounted, as by means of a clamp 40, on a pedestal 36 which extends outward and downwardly from the outer and upper end of a base 34. At its lower end the insulator 38 carries a contact member which is adapted to be engaged by a cooperating contact making member carried at the lower end of a rocking insulator 62 which is mounted on and rocked with a shaft 60 that is oscillated to rock the insulator from the position indicated in full lines in Figure 1 to the position indicated in dotted lines thereon. For a more complete description of the structure of the switch, reference is had to our above mentioned application.

Motor drive the two discs together, the discs may be rotated with respect to one another through a limited angle. The discs may then be secured together in the desired relation by again tightening the bolts. Eye 102 is readily interchangeable or connectible to any other operating mechanism, so that the switch proper may be operated either manually through suitable mechanism forming no part of the present invention, or by power. When the plates 108-110 are secured together there is a positive driving connection between the shaft 112 and the switch, that is, a connection such that for any movement of the shaft there must be a corresponding movement of the switch, and vice versa.

The motor 114 (see Fig. 2) receives current through lead wires 116 and 118 to actuate it always in the same direction, as will be described hereinafter. A magnetically released braking device 120 is connected in series with one of the lead wires, and operates automatically to stop the motor when the current is turned off. The brake of this device 120 engages the flanges or cylindrical surfaces of opposite sides of a flexible coupling 120'120'. Thus the coupling flanges perform the dual function of transmitting power as through a leather or rubber disc and also of acting as brake drums. A relatively small, high speed motor is employed by preference, and casing 122 houses reducing gears of any preferred construction. Flexible coupling 124 drives the worm shaft 126 for actuating a worm wheel in casing 128, which worm wheel actuates shaft 130. (SeeFig. 6.) Clutch member 132 which is slidably keyed upon shaft 130 is forced by spring 134 into positive clutched engagement with cooperating clutch member 136 splined on shaft 112. The movable clutch member 132 has a series of notches adapted to cooperate with a plurality of teeth on the face of the companion clutch member 136. It will be apparent that actuation of the motor will slowly rotate shaft 112 to reciprocate pitman 98 and open and close all the switching devices simultaneously. By stopping thernotor at appropriate times, the switches can be left either open or closed, and the irreversible worm trans- -mission to the shaft 130 assures that they will remain locked in that position until subsequent actuation of the motor. By irreversible worm transmission we mean a worm transmission wherein the worm wheel is driven by the worm but it cannot drive the worm. Thus power is always transmitted in one direction, namely, from the worm to the worm wheel, but cannot be transmitted in the other direction, namely, from the worm wheel to the worm.

The swing of the movable insulator is substantially from 15 back of vertical in open position to 45 in front of vertical in closed position. Spring 90 helps to reduce the work of raising the insulator when the switch is closed. It also operates to shift the position of equilibrium of the movable insulator toward the center of its path of movement, where the effective leverage of the power transmission linkage is least and the velocity of movement greatest.

To minimize difliculty in assembly, and eliminate wear or breakage due to warping or slight deformation of the supports for motor 114 and gearing 122, we provide an additional universal coupling 125 between the motor and the gearing, and use this coupling also as the drum for the electric brake 120.

Remote control A suitable remote control wiring diagram for such a system is given in Fig. 5. From the mains 138 and 140 connecting wires 142 and 144 respectively lead to posts 146 and 148 on the terminal board 150. For the sake of ease in description assume direct current is employed on mains 138 and 140 and that main 138 is positive, while main 140 is negative. It is to be understood that alternating current may with equal facility be employed as the motor 114 is a universal type operable on either A. C. or D. C. In case the negative 140 is grounded, wire 142 only need be equipped with a disconnecting switch 152 and a fuse 154. Wire 118 leads through brake solenoid 120 and one'side of disconnecting switch 156 to three spaced motor operating terminals 158, 160 and 162. With switches 152 and 156 closed, it will be apparent that the motor will be operated when any one of the three motor contacts is connected to the negative line. For the automatic control of these connections, shaft 112 carries cams for actuating a circuit making element 164 twice in each revolution to make and break contact with contact 158; a double pointed contact making element 166 completing a cycle once in each revolution of shaft 112 and making contact with contacts 160 and 168 alternately; and another double pointed contact making element 170 similarly actuated to make contact alternately with contacts 162 and P172. Wire 116 connects through the other side of double pole switch 156 to post 146. Switch arm 164 and post 172 and 168 are connected directly to point 148.

The operators control switch 176 may be situated at any suitable point. It is connected to $118 negative line through wire 178, and makes contact selectively with points 180 and 182. Contact 180 is connected through wire 184, post 186 and wire 187 with the double pointed contact element 166; and contact 182 is similarly connected through wire 188, post 190 and wire 192 with contact element 170.

The position illustrated corresponds to the open position of the main switch, the circuit of red light 194 being open and the circuit of the green light 204 being closed. The operation is as follows: To operate the mechanism to close the main switch, lever 176 will be thrown to engage contact 182 establishing 'a motor circuit as follows: From the positive line through switch 152, fuse 154, wire 142, post 150, switch 156, wire 116 through motor 114, through Wire 118, solenoid 120, back through switch 156 to contact 162, contact maker 170, wire 192, post 190, wire 188, to contact 182; and through control arm 176 and wire 178 to the negative line. The motor will accordingly be energized. This will also close the circuit of the red light. As the cam shaft 112 rotates, the first thing that occurs is movement of the contactor 166 away from stationary contact 168 due to the spring arm 220 riding out of the corresponding cam notch. This leaving of contact 168 is almost instantaneous after closing of the switch 176. This opening of the circuit at contact 168 puts out the green light until the contact 166 arrives in contact with the opposite stationary contact 160 whereupon the green light circuit is again established by the simultaneous arrival of motor switch contactor 164 upon the stationary contact 158. During the time that the green light is out opening of the control switch 176 will interrupt operations, but after the green light lights up again the operation will be completed because the motor switch 164 has then assumed control. The green light cannot light up until the motor switch 164-158 has been closed. After the green light has again become lighted as above described, the control switch 176 may be left closed or opened or in fact thrown over to the opposite contact 180 all without affecting the completion of the main switch closing operation. If the control switch is left in contact 180, or is opened after the green light comes on again, the motor drives the mechanism to position to close the main switch and also to shift the cams to a position which will cause the motor control switch 164 to open and motor starting switch -162 also to open and light control switch 176-172 to close to maintain a lighting circuit for red lamp 194. This is necessary because opening of the motor control switch would otherwise open the previous supply circuit for red lamp 194.

If the switch 176 is drawn over the contact 182, the motor mechanism first completes its throw and thereafter immediately proceeds to make the next stroke, i. e., the switch opening movement.

Briefly the lights operate as follows: when the main switch is in closed position, the red lamp is lighted and the green light is out. When the main switch is open the green lamp is lighted and the red lamp is out. Assume the main switch is closed and red lamp is on and it is desired to open the main switch. The control switch 17 6 is thrown to contact 180. The operation then proceeds to the point where motor control switch 164 opens and stops the movement of the operating parts. At the same time the circuit for the red lamp is opened by motor control switch 164 and the circuit of the green lamp is closed at contacts 166-168. If the main switch is now to be opened the control switch is thrown to contact 182. The operations will be analogous to the previously described operations the action of the red lamp now duplicating the action of the green lamp previously described.

The mechanical elements necessary for automatically operating the contact makers above described are relatively simple. Shaft 112 is car ried by two spaced standards 212 (see Figs. 2 and 4). Contactors or switches 164, 166 and 170 are formed of blocks of insu'ating material pivoted at 214 and normally urged in counterclockwise direction by coil springs 216, the lower ends of which hook over a removable pin 218. Spring metal arms 220 are attached to the blocks and bent up to form contact shoes for single cams 222 and 224 and double cam 226 which latter operates contact arm 164. Cams 222 and 224 each comprise a circular periphery with a single notch. These notches are placed opposite each other i. e., substantially apart. For contact 164 two notches are required. To simplify the manufacture and to provide for ease of adjust-ment, dup icate blanks are employed for all the cams, and cams 226 have the side opposite the notch cut off as indicated at 227' in Fig. 6 to prevent interferring with the notch in the other cams. These cams 226 are placed on the shaft 112 with the notched portions projecting in opposite directions. All the cams are adjustable on the shaft by means of set screws 227.

An extended lower contact 228 formed of an angle strip of copper functions as contacts 158, 160 and 162, and an upper angle strip 230 functions as contacts 172 and 168. Contact element 164 carries a single downwardly curved metallic arm 232, and two duplicate arms 232 diverging in opposite directions are mounted on contact elements 166 and 170. connect the metal'ic elements 232 to appropriate binding posts on the insulating panel 236.

Manual operation The above mentioned parts are provided for complete automatic control of the switch unit from a remote point, but it is desirable that the switch be capable of manual operation, in case motor 114 or any of the means for supplying power to the motor or transmitting it from the motor to shaft 112 fails. Clutch member 136 carries ratchet teeh 238 at its periphery, engaged by a suitable pawl 240 (see Fig. 6), to prevent movement of the shaft except in a counterclock- 1 wise direction as seen in Fig. Fig. 3. It also carries an armular rib 242 notched at 244 at two points spaced 180 degrees apart. A sleeve or hub 246 journaed on the hub of part 136 carries a radial arm 248 equipped with a suitable pawl 250 for operative engagement with notches 244 to rotate shaft 112. The arm is prolonged into a socket 252 adapted to receive a bar or short length of pipe 255 for manual operation of the switch. The arm 248 is moved down inside the Suitable flexible leads 234 the clutch parts out of engagement. The yoke carries a lug 262 projecting from the side thereof past a notch 264 in a locking lever 266 pivoted at 268 and normally urged into locking position by a spring 270. A cover indicated in dotted lines at 272 is provided with a door 274, opening of which permits access to sockets 252 and 260. After disengaging the clutch, the operator will place handle 255 in socket 252 and throw the same over through substantially 180", until arm 248 engages set screw 275 adjustably mounted on lever 266. This withdraws notch 264 from engagement with the yoke, and spring 134 will move the clutch teeth into engagement locking the parts with the switch in either completely open or completely closed position. The entire motor unit is mounted on a suitable concrete base 276 (see Fig. 1) in suitable position for connection by pitman 98 to the main switch proper.

It should be noted that in case manual operation is necessitated by inoperativeness of the motor, switch 156 may be opened to permit repair work on the same, without interfering with the operation or indication of the red and green lights in the control station, which will indicate at that point whenever the switch is changed manually or by the motor.

When the switch is manually operated, control switch 156 should be open. If, however, it were left closed, the only result would be that after an initial manual movement, the motor would run idle while the manual operation was completed. In any installation where this is considered undesirable, we prefer to provide simple means for automatically opening the motor circuit, to render the apparatus foolproof in this respect. Referring to Figure 7 a clip 278 bolted in place with the upper half of casing 128, provides pivotal mounting for an arm 280, preferably of insulating material, extending up and across over the top of casing 128. A small bracket 280 carries a head 282 engaging a slot 284 in the upper bight of yoke 254. The laterally projecting upper end of arm 280, carries contact means 286 movable into and out of operative engagement with stationary con tact means 288 mounted on top of casing 128.

It will be obvious that shifting yoke 254 to the left as seen in Fig. 7 to permit manual operation of the switch, will disconnect the motor, and connect it in again when the operation of the switch has been completed.

Without further elaboration, the foregoing will so fully explain the gist of our invention, that others may, by applying current knowledge, readily adapt the same for use under various conditions of service. It will, for instance, be obvious that the remote control means disclosed is applicable for operating any mechanically actuated switch, such as that disclosed in the co-pending application of Ernest H. Jacobs, Ser. No. 381,234, filed May 14, 1920, issued as Patent No. 1,631,261, on June 7, 1927.

Many alterations and modifications may readily be made by those skilled in the art without eliminating certain features which may properly be said to constitute the essential items of novelty involved, which items are intended to be defined and secured to us by the following claims:

We claim:-

1. In a switch system, a switch operating means comprising in combination, a motor. a transmission including in series, irreversible transmission elements permitting said motor to move said switch but not vice versa, a releasable connection, and a positive transmission to the switch proper, manual means for disconnecting the releasable connection and manually operating a portion of the switch operating means to actuate the switch, and means for automatically establishing said releasable connection at the end of the manual movement.

2. In combination, a switch, a shaft, positive operating connections between the shaft and the switch, a second shaft, self-locking power means for driving the second shaft, a releasable clutch normally establishing positive driving connections between the shafts, means for releasably holding the movable member of the clutch in inoperative position, means for manually turning the first shaft when the clutch is released, and means for automatically releasing the movable clutch member and closing the clutch when said first shaft has been turned a predetermined distance manually.

3. In combination, a switch, a shaft, positive operating connections between the shaft and the switch, a second shaft, an electric motor, selflocking driving connections between the motor and the second shaft, a releasable clutch normally establishing positive driving connections between the shafts, means for releasably holding the movable member of the clutch in inoperative position, means for manually turning the first shaft when the clutch is released, means for automatically releasing the movable clutch member and closing the clutch when said first shaft has been turned a predetermined distance manually, and means for opening and closing the circuit of the motor in accordance with opening and closing of the clutch.

4. In combination, a switch, a shaft, positive operating connections between the shaft and the switch, a second shaft, an electric motor, selflocking driving connections between the motor and the second shaft, a releasable clutch normally establishing positive driving connections between the shafts, and means for opening and closing the motor circuit in accordance with release and reestablishment of the clutch.

5. In a switch operating mechanism wherein an operating shaft is operated from either of two operating means, a clutch normally connecting one of said means to the shaft, holding means for holding the clutch out of said connecting engagement, and means operated responsive to a predetermined movement of said other operating means for releasing said holding means.

6. In a switch operating mechanism wherein an operating shaft is operated from either of two operating means, a clutch normally connecting one of said means to the shaft, locking means included in the last mentioned means for locking said shaft in position, holding means for holding the clutch out of said connecting engagement, and means operated responsive to a predetermined movement of said other operating means for releasing said holding means.

7. In combination, a switch operating rod, a shaft rotatable in one direction for moving said rod into the switch closing and switch opening position, a clutch including a driven member which is fixed to the shaft and a driving member free to rotate with respect to said shaft, means normally clutching the two members together, latching means for holding the clutch members in non-clutching engagement, means for operating the shaft while the clutch is in non-clutching engagement, and means effective responsive to a predetermined movement of the shaft for releasing said latching means.

8. In combination with a high voltage switch having normal open and closed positions, a shaft having mechanical connection with the switch for driving it, said shaft being rotatable in one direction for opening the switch and in the same direction for closing the switch, said mechanical connection including a crank connection that passes through toggle position twice for each complete rotation of the shaft, said crank connection being in one toggle position when the switch is closed and in its other toggle position when the switch is open, said mechan ical connection including means for adjusting the relative angular positions of the operating shaft and the switch to establish the positions of toggle when the switch is in its alternate positions, means for locking the adjusting means in adjustment, electric motor driving means for the shaft, and limit switches for disabling the motor drive upon the completion of each half revolution of said shaft.

9. In combination with a high voltage switch having normal open and closed positions, a shaft having mechanical connection with the switch for driving it, said shaft being rotatable in one direction for opening the switch and in the same direction for closing the switch, said mechanical connection including a crank connection that passes through toggle position twice for each complete rotation of the shaft, said crank connection being in one toggle position when the switch is closed and in its other toggle position when the switch is open, said mechanical connection including means for adjusting the relative angular positions of the operating shaft and the switch to establish the positions of toggle when the switch is in its alternate positions, means for locking the adjusting means in adjustment, electric motor driving means for the shaft, limit switches for disabling the motor drive upon the completion of each half revolution of said shaft, said electric motor driving means including a speed reducing gearing which can transmit power from the motor to the shaft and is self-docking against reverse power transmission to obtain a positive control of the movement of the switch, and a releasable clutch between the gearing and the shaft to permit driving of the shaft and actuation of the switch independent of the motor driving means.

10. in combination with a high Voltage switch having normal open and closed positions, a shaft having mechanical connection with the switch for driving it, said shaft being rotatable in one direction for opening the switch and in the same direction for closing the switch, said mechanical connection including a crank connection that passes through toggle position twice for each complete rotation of the shaft, said crank connection being in one toggle position when the switch is closed and in its other toggle position when the switch is open, said mechanical connection including means for adjusting the relative angular positions of the operating shaft and the switch to establish the positions of toggle when the switch is in its alternate positions, means for locking the adjusting means in adjustment, electric motor driving means for the shaft, limit switches for disabling the motor drive upon the completion of each half revolution of said shaft, said electric motor driving means including a speed reducing gearing which can transmit power from the motor to the shaft and is self-locking against reverse power transmission to obtain a positive control of the movement of the switch, a

releasable clutch between the gearing and the shaft to permit driving of the shaft and actuation of the switch independent of the motor driving means, and switching means for disabling the motor driving means responsive to the release of the clutch.

11. In combination with a high voltage switch having normal open and closed positions, a shaft having mechanical connection with the switch for driving it, said shaft being rotatable in one direction for opening the switch and in the same direction for closing the switch, said mechanical connection including a crank connection that passes through toggle position twice for each complete rotation of the shaft, said crank connection being in one toggle position when the switch is closed and in its other toggle position when the switch is open, said mechanical connection including means for adjusting the relative angular positions of the operating shaft and the switch to establish the positions of toggle when the switch is in its alternate positions, means for locking the adjusting means in adjustment, electric motor driving means for the shaft, limit switches for disabling the motor drive upon the completion of each half revolution of said shaft, said electric motor driving means including a speed reducing gearing which can transmit power from the motor to the shaft and is self-locking against reverse power transmission to obtain a positive control of the movement of the switch, a releasable clutch between the gearing and the shaft to permit driving of the shaft and actuation of the switch independent of the motor driving means, and means responsive to an operation of the shaft through 180 for restoring the clutch in the event that it has been released.

12. In combination with a high voltage switch having normal open and closed positions, a shaft having mechanical connection with the switch for driving it, said shaft being rotatable in one direction for opening the switch and in the same direction for closing the switch, said mechanical connection including a crank connection that passes through toggle position twice for each complete rotation of the shaft, said crank connection being in one toggle position when the switch is closed and in its other toggle position when the switch is open, said mechanical connection including means for adjusting the relative angular positions of the operating shaft and the switch to establish the positions of toggle when the switch is in its alternate positions, means for locking the adjusting means in adjustment, electric motor driving means for the shaft, limit switches for disabling the motor drive upon the completion of each half revolution of said shaft, said electric driving means including a speed reducing gearing which can transmit power from the motor to the shaft and is self-locking against reverse power transmission to obtain a positive control of the movement of the switch, a releasable clutch between the gearing and the shaft to permit driving of the shaft and actuation of the switch independent of the motor driving means, switching means for disabling the motor driving means responsive to the release of the clutch, and means responsive to an operation of the shaft through for restoring the clutch in the event 1 5 gearing driven by the motor, a driven shaft driven by the gearing through a non-slip clutch and having a positive driving connection with said switch, limit switches controlled by the driven shaft and controlling the motor circuit, and switching means controlled by the position of the clutch for preventing operation of the motor when said driven shaft is declutched from the gearing.

14. Apparatus of the character described comprising a driving motor, a high voltage switch to be driven thereby, unidirectional power transmitting mechanism operatively associating said motor with said switch comprising speed reducing gearing driven by the motor, a driven shaft driven by the gearing through a non-slip clutch and having a positive driving connection with said switch, alternate driving means for the driven shaft independent of the motor and the gearing, said alternate driving means being operable when the clutch is in its declutching position, and means responsive to the completion of an operation by said alternate driving means for restoring the clutch to its clutching position.

15. Apparatus of the character described comprising a driving motor, a high voltage switch to be driven thereby, unidirectional power transmitting mechanism operatively associating said motor with said switch, comprising speed reducing gearing driven by the motor, a driven shaft driven by the gearing through a non-slip clutch and having a positive driving connection with said switch, limit switches controlled by the driven shaft and controlling the motor circuit, switching means controlled by the position of the clutch for preventing operation of the motor when said driven shaft is declutched from the gearing, alternate driving means for the driven shaft independent of the motor and the gearing, said alternate driving means being operable when the clutch is in its declutching position, and means responsive to the completion of an operation by said alternate driving means for restoring the clutch to its clutching position.

CHRISTEN CHRISTENSEN. ALWIN G. STEINMAYER.

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