US3307077A

US3307077A - Flat package bridge rectifier

Info

Publication number: US3307077A
Application number: US502958A
Authority: US
Inventors: Bernstein Bernard
Original assignee: Individual
Current assignee: Individual
Priority date: 1965-10-23
Filing date: 1965-10-23
Publication date: 1967-02-28
Anticipated expiration: 1984-02-28

Description

Feb. 28, 1967 B. BERNSTEIN FLAT PACKAGE BRIDGE RECTIFIER Filed Oct. 25, 1965 INVENTOR.

BERNARD BERNSTEIN m'ronusvs 3,307,077 FLAT PACKAGE BRIDGE RECTIFIER Bernard Bernstein, 3900 Kings Highway, Brooklyn, N.Y. 11234 Filed Oct. 23, 1965, Ser. No. 502,958 9 Claims. (Cl. 317-99) This invention relates to rectifiers, and more tifiers.

The general object of the invention is to improve such rectifiers. A more particular object is to provide such a rectifier in the form of a fiat package which is sturdy and inexpensive, both for parts and for assembly labor. Another object is to provide a rectifier package which is unusually compact in size, and which is made up of a minimum number of parts. To accomplish the foregoing general objects, and other more specific objects which will hereinafter appear, my invention resides in the bridge rectifier elements and their relation one to another as are hereinafter more particularly described in the following specification. The specification is accompanied by a drawing in which:

FIG. 1 is a perspective view showing parts of the rectifier in spaced relation;

FIG. 2 is a plan view nal strips and cover;

FIG. 3 is a similar view after adding the top terminal strips, and before adding the cover;

FIG. 4 is a vertical section taken on the line 44 of FIG. 3 after adding the cover;

FIGS. 5 and 6 are plan and edge views respectively of a modification; and

FIG. 7 is a diagram schematically explaining the electrical relation of the rectifier stacks.

Referring to FIG. 2 of the drawing, the rectifier comprises four stacks of

rectifier cells

12, 14, 16 and 18 arranged in a square. There are four elongated terminal strips, one of which is indicated 'at 20 in FIG. 1. Each has a soldering lug (64 in FIG. 1) for external connection. One pair of two such terminal strips are arranged collaterally beneath 24 in FIGS. 2 and 4. nal strips is disposed rectifiers, especially selenium particularly to closed end bridge recprior to addition of the top termiabove the stacks, and transversely of the first pair, as is indicated at 26 and 20 in FIG. 3. There is also a means, in this case a cover 30, for compressing the terminals and stacks for good electrical contact. The assembly then has four soldering lugs for external connection to the corners of the closed end bridge of rectifiers formed within the package.

The terminal strips are preferably made of resilient metal, and are concavo convex, so that when loaded they resilient pressure to the stacks of The terminal strips may be made of hard cold rolled steel, or they may be made of spring steel, and in either case they are preferably tinned or coated with some other suitable corrosion resistant metal.

The cells and terminal strips are housed in a molded insulating case having a bottom 32 (FIG. 1) and four

edge walls

34, 36, 38 and 40, at least some of which have vertical slots which are open at the top. There could be a single slot in each of the four walls, making four slots in all, for the four soldering lugs, but it is considered United States Patent 0 3,307,077 Patented Feb. 28, 1967 more convenient for eventual wiring in a circuit to provide two slots on each of two adjacent walls, as shown in FIG. 1. The wall 34 has two

full depth slots

42 and 44, while the adjacent wall 36 has two

short slots

46 and 48.

There is a first partition 50 which extends from the slotted wall 34 to the opposite wall 38, and a second partition which extends from the second slotted wall 36 to the full depth in the region between the partition 50 and each of the

sidewalls

36 and 40. Differently expressed, it is made up of

short pieces

52, 54, 56 and 58.

The terminal strips (20 in FIG. 1) are notched at the side edges as shown at 62, to receive the

parts

52, 54 or the parts 56, 58. The soldering lug 64 at one end of the terminal strip is dimensioned to pass through

slot

42 or 44. Thus two of the terminal strips may be laid on the bottom 32 of the case, one on each side of partition 50, with the lugs projecting through the

slots

42 and 44.

The rectifier stacks are built up of superposed selenium cells. One such cell is indicated at 66 in FIG. 1. As here illustrated each stack comprises four cells, but the number used may vary. The cells may be conventional selenium cells having a suitable base metal, typically aluminum. The selenium is preferably vacuum deposited on the aluminum. In simplest form the cells are square, as here illustrated. The cells are dimensioned to be received transverse partition 5258.

The

top terminal strips

26 and 20 overlie the first partition 50, as shown in FIGS. 3 and 4. They have soldering lugs 60 and 64 which pass through the

short slots

46 and 48 previously referred to. In preferred form the first partition 50 is interrupted, somewhat like the second partition, but for only a slight depth, as shown at 68 in FIG. 1, this depth being sufiicient to receive the top terminal strips, and for that reason the top strips, like the bottom strips, are preferably notched at the sides 'as shown in FIG. 1.

ing a depending locating stud 74 at the center, and having four holes 76 near its periphery dimensioned to frictionally receive the four studs 72. The cover may be molded of an insulaing material, preferably the same material as the case.

This material may be a plastics material having suitable characteristics in respect to electrical insulation and moldability. Nylon is a satisfactory material, but I prefer to use a polycarbonate plastic such as Lexan made by General Electric Company.

In FIG. 4 the

bottom terminal strips

22 and 24 are shown disposed with the convex face upward, but they can be inverted, with some advantage either way. The top terminal with the convex face downward, this being done primarily to insure safe interfit of the side notches 62 of the top strips with the upper edge of the partition 50.

Dependstrips

26 and 20 preferably are disposed,

able location and holding of the top terminal strips is a labor saving convenience when applying the cover plate. Depending on the material used, the cover may be secured to the base by use of a solvent, or a cement, or by welding. In the case of nylon it would not be feasible to use any presently available cement. The welding may be performed in different known ways, one of which is by means of ultrasonic vibration. The cover is applied under a desired force to place the stacks and terminal strips under a desired preloading pressure. A suitable assembly fixture may be employed for this purpose.

It will be evident that the four stacks of rectifier cells are disposed in the arms of a conventional electrical bridge of the closed end type, and that the terminal strips act also as jumpers at the corners of the bridge. Alternating current may be applied to either the pair of

bottomterrninals

22, 24, or to the pair of

topterminals

26, 20, with appropriate polarity of the selenium cells, and the other pair of terminals delivers the rectified output. The latter may be obtained in either polarity, as by turning over all of the stacks of cells. The electrical arrangement is symbolized in FIG. 7 in which the four stacks of cells are indicated by the oppositely facing

triangles

16, 12, and 14, 18, and in which the alternating current is shown applied to the terminal strips 26 and'20, while the direct current is taken from the

terminal strips

22 and 24.

If desired the case may be modified to provide a flange which protects the soldering lugs. Such an arrangement is shown in FIGS. 5 and 6 in which the case 80 has connected

flanges

82 and 84 to physically protect the two pairs of projecting soldering lugs. In other respects the construction is the same as that already described. The flanges may be molded integrally with the case.

The construction shown is inexpensive because of the minimum number of parts employed. It is also very compact. The rectifier illustrated in FIGS. 1-4 has a case which is only 4 inch by inch. The cells are 0.29 inch square, and have a thickness of 0.025 inch, there being four cells in each stack as here illustrated. The dimensions may be varied, it being understood that quantitative values have been given solely by way of illustration, and are not intended to be in limitation of the invention.

The number of cells in each stack may be varied, with appropriate change in the height of the case. Even with the same case, the number of cells may be varied by changing the thickness of the individual cells. Alternatively, the height of the case may be dimensionedfor say five cells, and then when only four cells are to be used, a filler piece of plain metal may be employed in lieu of the fifth cell. i

It is believed that the construction and method of assembly of my improved flat package bridge rectifier, as well as the advantages thereof, will be apparent from the foregoing detailed description. It will also be apparent that while I have shown and described the invention in a preferred form, changes may be made without departing from the scope of the invention as sought to be defined in the following claims. four stacks being arranged in a square means merely that the stacks are arranged two by two, rather than meaning equality of dimension, although it is preferable and most convenient to employ square cells so that all four terminal strips may be alike.

I claim:

1. A fiat package bridge rectifier comprising four stacks of imperforate rectifier cells, said stacks being arranged relative to one another in a square, two pairs of elongated terminal strips, the two strips in each pair being collateral of one another, one pair being beneath the four stacks and the other pair being above the four stacks, one pair being disposed transversely of theother pair, said assembly of cells and terminal strips forming a bridge of four rectifiers with four terminal strips for external connections, the terminal strips being made of resilient metal, and each being concavo convex at each stack, and a hous- In the claims the reference to 4 ing around the stacks and terminal strips, said housing being so dimensioned as to bear against the four terminal strips and to load the said terminal strips in order to apply resilient pressure to the stacks of cells.

2. A flat package bridge rectifier comprising four stacks of rectifier cells, said stacks being arranged relative to one another in a square, two pairs of elongated terminal strips, the two strips in each pair being collateral of one another, one pair being beneath the four stacks and the other pair being above the four stacks, one pair being disposed transversely of the other pair, said assembly of cells and terminal strips forming a bridge of four recti-l fiers with four terminal strips for external connections, a molded insulating case for housing the cells and terminal strips, said case having a bottom and four edge walls at least some of which have slots to receive soldering lugs, a first partition extending from a first slotted wall to the opposite wall, a second partition extending from a second slotted wall to the opposite wall, each partition being interrupted at points between the other partition and the edge walls, the terminal strips being notched at the side edges to receive the interrupted partitions and each having a soldering lug at one end which passes through one of the slots, the cells being dimensioned to be received within the partitions, and a cover disposed over the case and secured thereto and exerting pressure on th strips and stacks.

3. A flat package bridge rectifier comprising four stacks of rectifier cells, said stacks being arranged relative to one another in a square, two pairs of elongated terminal strips, the two strips in each pair being collateral of one another, one pair being beneath the four stacks and the other pair being above the four stacks, one pair being disposed transversely of the other pair, said assembly of cells and terminal strips forming a bridge of four rectifiers with four terminal strips for external connections, a molded plastic case for housing the cells and terminal strips, said case having a bottom and four edge walls, one of which has two full depth slots, and an adjacent one of which has two short slots, a first partition extending from th first slotted wall to the opposite wall, a second partition extending from the second slotted wall to the opposite wall, the second partition being interrupted at full depth at points between the first partition and each of the edge walls to which it runs, the bottom terminal strips being notched at the side edges to receive the interrupted partition and having soldering lugs at one end to passthrough the full depth slots, the cells being dimensioned to be received within the partitions, the top terminal strips overlying the first partition and having soldering: lugs projecting through the short slots, and a plastic in-- sulation cover disposed over the case and secured thereto and exerting pressure on the strips and stacks.

4. A rectifier as defined in claim 2, in which the ter-- minal strips are made of resilient metal and are each concavo convex at each stack and in which the terminal strips are loaded by means of the cover to apply resilienti pressure to thestacks of cells.

5. A rectifier as defined in claim 2, in which the partitions near the edge walls have upstanding studs, and in which the partitions have a cruciform center and at said cruciform center have a hole, and in which the cover has a depending locating stud at its center to fit in said hole, and has four holes near its periphery to receive the aforesaid studs.

6. A rectifier as defined in claim 2, in which the cells are square, and in which the partitions forrn compartments and said compartments formed by the partitions for receiving the cells are square, and in which the case and its cover are square.

7. A rectifier as defined in claim 3, in which the terminal strips are made of resilient metal and are each concavo convex at each stack and in which the terminal strips are loaded by the cover to apply resilient pressure to the. stacks of cells.

8. A rectifier as defined in claim 3, in which the first partition is interrupted like the second partition but for only a slight depth sufficient to receive the top terminal strips, and in which the latter are notched at the sides like the bottom terminal strips.

9. A rectifier as defined in claim 3, in which the partitions near the edgewalls have upstanding studs, and in which the partitions have a cruciform center and at said cruciform center have a hole, and in which the cover has a depending locating stud at its center to fit in said hole, and has four holes near its periphery to receive the aforesaid studs.

6 References Cited by the Examiner UNITED STATES PATENTS 2,215,667 9/1940 Sherman 3172.34 3,211,873 12/1965 Vigren et a1. 200-166 FOREIGN PATENTS 130,847 1/ 1949 Australia.

M. GINSBURG, Assistant Examiner.

Claims

1. A FLAT PACKAGE BRIDGE RECTIFIER COMPRISING FOUR STACKS OF IMPERFORATE RECTIFIER CELLS, SAID STACKS BEING ARRANGED RELATIVE TO ONE ANOTHER IN A SQUARE, TWO PAIRS OF ELONGATED TERMINAL STRIPS, THE TWO STRIPS IN EACH PAIR BEING COLLATERAL OF ONE ANOTHER, ONE PAIR BEING BENEATH THE FOUR STACKS AND THE OTHER PAIR BEING ABOVE THE FOUR STACKS, ONE PAIR BEING DISPOSED TRANSVERSELY OF THE OTHER PAIR, SAID ASSEMBLY OF CELLS AND TERMINAL STRIPS FORMING A BRIDGE OF FOUR RECTIFIERS WITH FOUR TERMINAL STRIPS FOR EXTERNAL CON-