US1824304A - Bearing for electrical condensers - Google Patents

Description

Sept. 22, 1931. T. J. SCOFIELD V 1,324,304

- BEARING FOR ELECTRICAL CONDENSBR Filed NOV. 9, 1929 .9" f f j WW I I GD as w (H) (ID 11) GD 11) m m J Tb okiii'iifc'i/w BYQZW. W

' ORNEY 5 the rotor plate and .10 rotor shaft and the 2.) shown in Fig. 3.

as in Fig. 1.

Patented Sept. 22, 1931 UNITED STATES PATENT OFFICE maonona I, seem, or

JACKSON. IICKIGAN, ASSIGHOi 1'0 TEE SPARKS- WITHINGIOII comm, A CORPORATION 01' OHIO m 103 ELECTRICAL ooxmms'aas Application lled Ievsnber 0, ma. lerlal Io. 406,80.

This invention relates to electrical gang condensers such as are used in radio sets.

One of the objects of the invention is to co struct the bearings of the condenser so that shaft assembly can be readily placed in position.

Another object of the invention is to construct the bearin contacts so that there will be good electrica spring contact between the frame of the condenser.

Another object is to arrange the hearing so that there is continual position regardless of jars or vibrations to 15 which it may be sub'ected while in use.

:0 used in radio sets.

' Fig. 2 is an end view of the condenser frame as viewed from the ri ht of Fig. 1. I Fig. 3 is a view of t e bearing plate.

Fig. 4 is an end view of the bearing plate Fig. 5 is an elevation of the compression plate of the bearing. 5

- Fig. 6 is a view of the condenser with the shaft and rotor assembly being. placed" in a? position.

Fig. 7 is a horizontal section view of the right-hand end be as shown in Fig. 1. Fig. 8 is a view of t e spring contact for the left-hand end oftherotor shaft as shown Fi 9 is a lo 'tudinal section taken on the l nes A-A 0 Fig. 8.

"Gang condensers used in radio sets are precision instruments and the mechanical v4o movement of the rotor plates in respect to the stator plates must be correct or else "undesired variations in capacity or even shortcircuits will result. It is necessary to have the rotor shaft revolve in a snug fittin bear- 6 ing at'eachend for this reason. It is also necessary to have good electric contact between the rotor shaft and the frame of the condenser to conduct the signal currents.

To permit the ready insertion of the rotor 50 in the condenser one of the bearings of the frictional pressure to insure that the rotor will stay in the adjusted upwardly awa makes a smooth fit with the rotor shaft.

screws to compress the springs and rotor shaft is made separate from the frame of the condenser. The shaft 1 of the rotor has flange or side bearin member 2 thereon near one end, as shown 0 earl in Figs. 6 and 7. A hole 3 is formed. in t e end member 5 4 of the condenser frame suflicientl large to rmit insertion of the shaft and t is flange 2 when the rotor assembly is inclined at a considerable angle such as shown in Fig. 6, for exam le. 0 bearing contact is made with this ole 3 and the size of such hole is immaterial so long as it is large enou h to permit the flange 2 to be inserted wit the rotor plates clearing the stator plates.

When the rotor shaft is assembled in the a rotor bushings 5 a fibre washer 6 may be placed on the inside of the flange 2.

The rotor assembly is pushed to the right, as shown in Fi 6 sutliciently to permit the end 8 of the she t to enter a snu bearin hole 1 9 in the end 10 of the con enser rame. While this operation is being performed the rotor plates would be positioned to project from the stator plates, as shown in the rawings.

The fibre washer 7 maythen be pushed on the right-hand end of the shaft 1, and brass bearing plate 11-is slipped over this end of the shaft. The hole in this bearing late so plate 11 is half-punched at 12 in the two 0 ite corners to form protuberant dowefis 13 which fit into depressions 13' into end 4 of the condenser frame. These dowels in conjunction with impressions in-the end member peroperly line the bearin plate 11 with the aring hole 9 to hold t e shaft in proper ition. Screws 14 are passed through oles 15 in the bearing plate and are threaded into the end member 4 to'ti htly clamp the plate against the end mem r of the condenser. 'Slotted plate 16 see Fig. 5) is dropped into position wit the slot 16' around the sha t 1. It is then slid to the I ri t, until the screws 14 pass through the ho es 17. Springs 18. are placed on these screws and nuts 19 are threaded on to the force the fibre washer 6. With plate 16 against this arrangement the flange 2 on; shaft 1 is 101'.

I the rotor shaft and the they fer to use the drum and forced to the right b the springs and frictionally engages the bre washers 6 and 7 so that suflicient friction is obtained to always hold the rotor shaft in any position in which it is turned while allowing suflioient freedom to manipulate the shaft for tuning purposes. If it is necessar to remove the rotor shaft and the assemble rotor plates the operation just described would be reversed.

In order to insure 00d contact between frame of the condenser a connecting member (Fig. 8) is used. This consists of a strip of ood conducting metal such as spring brass aving a slotted opening 21 in one end, preferably 'of oblong form, to permit adjustment and a hole 22 in the opposite end slightly smaller than the end of the shaft 8. This hole is stam ed so as to draw a protruding ring 23 to urnish a good bearing surface with the rotor shaft and a slot 24 is punched through this end to permit it to spring a art sufficiently to receive the end of the sha t and thus furnish spring contact therewith. This member 20 is laced over the end of the shaft 8 and the ot er end is fastened to the end plate 10 by means of screw 25 which passes through the opening 21 and is threaded into the end plate 10.

Any form of indicating drum 26 may be i used on the other end of shaft 1 and any form of rotating means may be employed. I prerotating means shown in the applicationof Theodore J. Scofield and William D. Miner (case #2-1) Serial No. 398,864, filed October 11 1929, but I have not shown these in this application as form no part of the invention claimed in this application.

end, an

Having described my invention, what I claim is:

1. In electrical condensers, a frame, a shaft, a side-bearing flange on said shaft near one end, an end member on said frame havin an opening adapted to permit the entry 0 said flange and shaft at an angle thereto, a bearing member fastened to sa1d end member and fitting on one end of said shaft outside of said flange, a plate fastened to said end member and engaging the inside of said flange, and a bearing member for the other end of said shaft.

2. In electrical condensers, a frame, a shaft, a side bearing flange on said shaft near one end member on said frame having an opening adapted to permit the entry of said flange and shaft at bearing fastened to said and member and fitting on one end of said shaft outside of said flange, a plate having a slot adapted to fit over the shaft and means to resiliently clamp the said plate against the inside of said flange. v

3. In electrical condensers, a frame, a shaft, a side bearing flange on said shaft near one said an angle thereto, a

end, an end member on said frame having depressions and an opening adapted to permit the entry of said flange and shaft at an angle thereto, a bearing fastened to said end member and fitting on one endof said shaft outside of said flange and having lugs fitting in said depressions, a plate having a slot adapted to fit over the shaft, and means to resiliently clamp the said plate against the inside of said flange.

4. In electrical condensers, a frame having a hole therein, a shaft, a flange on said shaft, said flange being small enough to enter said hole at an angle thereto, a plate fitting over said shaft on one side of sa1d frame, a plate fittin over said shaft on the other side of ame, bolts passing through said plates and frame, springs on said bolts, bearing against one of said plates, and nuts to compress said springs and clamp said plates against the sides of said flange.

In testimony whereof I have signed my name to this specification this 5th day of November, 1929.

THEODORE J. SCOFIELD.

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