US1821055A

US1821055A - Electrical condenser

Info

Publication number: US1821055A
Application number: US719114A
Authority: US
Inventors: Dubilier William
Original assignee: Dubilier Condenser Corp
Current assignee: Dubilier Condenser Corp
Priority date: 1924-06-10
Filing date: 1924-06-10
Publication date: 1931-09-01
Anticipated expiration: 1948-09-01

Description

Sept. 1, 1931. w. DUBILIER 1,821,055

ELECTRICAL CONDENSER Filed June 1o, 1924 INVENTOR MMM/r1 ,00a/UER i ATTORNEY Patented Sept. 1, 1931 UNITED STATES PATENT OFFICE WILLIAM DUBILIER, F NEW YORK, N. Y., ASSIGNOR lT0 DUBILIER-CONDENSER I CORPORATION, OF NEW YORK, N. Y., CORPORATION OF DELAWARE ELECTRICAL Application filed June 10,

I have invented certain improvements in electrical condensers, for use in oscillatory circuits, and especially radio apparatus.

In the manufacture and design of such condensers, particularly when the capacity of the condenser is tol be constant, sheets or plates of electrically conductive material separated by sheets of insulation are often assembled to form the stack or body of the condenser; and to maintain the capacity of the condenser at a fixed value, the sheets must be held in iirm engagement over their total area. The formation of cracks or air spaces, caused by the separation of any of the sheets, must be prevented by every possible means, because such cracks or spaces, even if exceedingly minute, with the high frequencies employed in signalling by radio,

' will inevitably give rise to great vaiiatioiis in the effect of the condenser, and often render the entire apparatus unserviceable.

In the practice Aof this invention, I incor- J porate in the condenser superior and effective means for keeping the stack tightly compressed, and for distributing the force of compression with the greatest 'uniformity over the area of the stack. Thus interior displacements and the occurrence of spaces or voids in the stack betweenthe sheets are wholly prevented.

The nature of the invention is set forth in the following description and the accompanying drawings, which disclose one or more constructions in which the principle of my invention is embodied. Of course, vI reserve the right to Amake changes that come within the scope of the invention as defined by the broad terms of the appended claims.

On the drawings, Figure l 1s an end .v1ew of one form of a condenser according to my invention;

Figure 2, a longitudinal section thereof;4

Figure 3, a similar section of another form of condenser; and ,A

Figure 4, a top plan of the condenser of Figure 3.

On the drawings, the same numerals iden? tify the same parts throughout.

VThe improvedcondensei, as shown in Fig- 54) ures 1 and 2, comprises a stack or body 1,

CONDENSER 1924. Serial No. 719,114.

consisting of thin plates or sheets of some electrically conductive material, such as metal foil 2, separated by insulation, such as sheets of mica 3. The top and bottom plates of the stack 1 are, of course, of insulation, and the stack is encircled-by a band clamp 4. This clamp 4 extends over substantially the Whole of one face of the body and is bent against the sides, with its extremities turned down upon the opposite face, this opposite `face being covered by a face Aplate 5, with which the extremities of the 'clamp make contact along the edges. Under the face plate and against the adjacent face of the stack 1, I place a cushion (i of some suitable yielding and resilient material of about the same size as one of the mica sheets; so that when the clamp is tightened, it will force the opposite faces of the stack towards each other, and through the plate 5 it-will exert suitable pressure upon the cushion 6. I prefer rubber as the best material for the cushion 6, because rubber is uniformly resilient and yielding throughout, andean just as easily be compressed in the direction of its thickness, as in the direction of either its length or breadth. Therefore, when the clamp 4 is tightened, the pressure which it Will cause to be. exerted upon the sheets of metal foil and mica will be evenly distributed ovei the entire area of the sheets of the stack 1. and slight iiiequalities in the bending of the. clamp or in the compression that might otherwise be exerted at various points in the stack, will be compensated, and the resultant compression will be'equalized over the total surface of the stack and the sheets constituting saine.

Figures 3 and 4, which illustrate a modification, show a condenser comprising two face plates, such as a cover plate 7 and a base, plate 8, the latter having extensions 9 at its opposite ends. These cover plates .are of some strong and stili insulating material, such as bakelite; While the face plate 5 above melitioned, is preferably of metal. The stack 1 lies between -the

plates

7 and 8, and to the extensions 9 are fastened clips 10 by means of suitable devices such as eyelet rivets 11;

andcach of these clips has a portion lient up and terminating in a flange 12 which overioa laps the adjacent edge of the cover plate 7 On one face of the stack and directly beneath either the plate 7 or on the plate 8, I place a cushion 6 as before, and around the two plates is a band clamp 13, which lies against the top plate and is bent down across the sides and over upon the outer surface of the base plate 8. The extremities of the clips 10 may have conductor fastening lugs la. In this type of condenser, both the clamp 13, and the, clips l0 are caused to engage the plates tight? ly, the clamp forcing the two

plates

7 and 8 towards each other, and the clips pressing down the ends of the plate 7. In this construction, the cushion 6 can be compressed to a greater extent, and not merely beneath the clamp 13.but along its edges also.

Of course, half of the sheets of foil 2 are of one polarity, and the other half are of opposite polarity. The ends of the two groups of sheets of foil of different polarity are shown as projecting out at the ends of the condenser, in Figure 2, to be united to the terminals of an electric circuit, and in Figures 3 and 4, the sheets of foil of one polarity will project out to be secured beneath the ad'acent clip 10; the remaining sheets of di erent polarity projecting out over the opposite extension 9 to be secured beneath the other clip 10, and the condenser can be put in circuit by joining electrical conductors to the clips by means of the lugs 14, or by fastening them with or without screws to theeyelet rivets 11. Of course 1n practice the sheets 2 and 34 can be made as thin or as thick as desired, and the condensers in any required sizes.

Having described my invention, what I believe to be new and desire to secure and protect by Letters Patent of the United States is :e-

1. A condenser comprising a pair of face plates, a stack consisting of sheets of electrically conductive material separated by 1nsulation between said plates, one of said plates having extensions at itsopposite ends, clips secured to said extensions and engaging the adjacent edges of the other plate, a clamp embracing the condenser and lying between said clips, and a plane cushion of uniformly yieldable and resilient material disposed against oneface of the stack, to cooperate with the clamp and enable pressure to be exerted evenly over the entire area of the sheets of conductive material and insulation when said clamp and said clips are tightened.

2. In a condenser structure a body comprising electrically conductive elements separated by dielectric material, and elastic means in contact with said stack for maintaining pressure directly on the stack over substantially the entire area thereof, whereby the condenser body is maintained in a state of uniform compression.

3. In a condenser structure a body comprising electrically conductive elements separated by dielectric material, and a cushioning means in contact with said stack for eX- erting pressure directly on the stack in such manner that a uniform pressure maintained at each point over the entire area of 'the stack regardless of irregularities in the cushion.

5. A condenser comprising a stack of armature members separated by dielectric material, a layer of uniformly elastic material in contact with said stack, said layer serving to exert a uniform degree of pressure over the entire active area of the stack, and clamp ing means for maintaining pressure on said elastic material.

6. In a condenser, a body having a pluralty of armature members separated by dielectric material and resilient means in contact with the body for exerting pressure at each point over the area of the body adjacent thereto, the pressure exerted at any point being independent of the pressure exerted at every other point.

7. A condenser comprising a-body of armature elements separated by dielectric material, a bearing plate for the body, a cushion of uniformly compressible and resilient material between the bearing plate and body, and clamping means for exerting pressure on the said bearing plate, cushion and body, whereby an even degree of pressure is exerted over the entire active area of the body to maintain constant the capacity of the condenser.

8. A condenser comprising a stack of armature elements separated by dielectric material, a face plate for the stack, a cushion of uniformly compressible and resilient material between the face plate and the stack, and a pressure clamp encircling the condenser and cushion and engaging the face plate, whereby an even degree of pressure is exerted over the entire active area of the stack to maintain constant the capacity of the condenser.

9. A condenser comprising a stack of sheets of electrically conductive material separated by dielectric material, a cushion of resilient rubber adjacent said stack, bearing plates enclosing said stack and cushion, and clamping means for exerting pressure on said bearing plates, whereby an even degree of pressure is exerted over the entire active area of the stack to maintain constant the capacity of the condenser.

10. A .condenser comprising a stack of sheets of electrically conductive material separated by dielectric material, a resilent Y rubber cushion adjacent said stack, bearing members enclosing said stack and cushion, and clips secured to one of said bearing members and engaging the djacent ends of the other bearing member 4whereby an even degree of pressure is exerted over the entire active area of the condenser stack to maintain constant its capacit In testimony whereof aiix my si nature.

WILLIAM DUBI IER.