US3524388A

US3524388A - Compressor housing fabricated from prefabricated sheet metal components

Info

Publication number: US3524388A
Application number: US684301A
Authority: US
Inventors: Arne F Enemark; Knud V Valbjorn; Kjeld Kjeldsen
Original assignee: Danfoss AS
Current assignee: Danfoss AS
Priority date: 1966-11-18
Filing date: 1967-11-20
Publication date: 1970-08-18
Anticipated expiration: 1987-08-18
Also published as: DK121879B; DE1503410A1; SE332042B; DE1503410C3; ES347300A1; GB1168876A; DE1503410B2

Description

United States Patent Inventors Appl. No.

Filed Patented Assignee Priority COMPRESSOR HOUSING FABRICATED FROM PREFABRICATED SHEET METAL COMPONENTS Primary E.raminer- Robert M. Walker A tto r ney Robert E. Burns and Emmanuel J. Lobato ABSTRACT: A compressor housing fabricated from sheet metal components which are assembled together. The comnents can be made of thinner metallic sheet material than heretofore possible and constitute components defining two parallel walls defining a partially enclosed space within which is inserted an up-ended band defining within this space chambers which function in use as silencing chambers. The comnents jointly define a cylindrical recess within which is in- W serted a pre-fabricated sleeve forming a cylinder. The parallel 6clalms4nrawmg Flgs' 'walls are each provided with an opening coaxial with said US. Cl 92/161, band, and a bearing sleeve is attached to at least one of the 417/3 l2 parallel walls coaxial with the opening thereon. Int. Cl F04b 39/12 The components are prefabricated independently and as- Field of Search 230/58, sembled without need of tools for assembly. They are soldered 232, 238 or otherwise fixed in assembly without fastensers.

9 l l 29 2O 6 3O 1 3 l0 35 I2 7 l 5 l 1H 8 I r r Patented Aug. 18, 1970 he t L of 2 55 4 4| 36 38 4O 57 a 54 J 1 i4 F1 i 9 l M g A 46 m: I 47 -.\I':.:;7 I v I 56 T H 50 f llwl 1M FIG. 4

COMPRESSOR HOUSING FABRICATED FROM PREFABRICATED SHEET METAL COMPONENTS This invention relates generally to compressors and more particularly to refrigerant compressors in which essential parts consist of sheet metal, and to a method of manufacturing such compressors.

In the known refrigerant compressors, essential parts of which consist of sheet metal, two problems are encountered among others. First, a rigid structure must be achieved, notwithstanding the employment of sheet metal, a comparatively thin material. Secondly, assembly of the parts should be simple enough to be carried out with a minimum of auxiliary tools. Special problems are encountered with regard to the cylinder which must be connected to other compressor components as rigidly as possible.

It is known to telescope two substantially cylindrical sheet metal components which have outward bends, and to form between them silencer chambers and valve chambers. The cylinder is in such cases provided with an extension engaging the valve mechanism and is supported by the two cylindrical parts in conjunction with a collar provided on the cylinder. This arrangement is braced by a pot-shaped insert which supports the shaft bearing. However, this construction is not very rigid. Assembly of such components requires a comparatively large number ofjigs and tools.

It is also known to produce a motor support for refrigerant compressors in the form of two telescoped sheet metal pots with silencing chambers being formed between their end faces. While this provides a rigid support structure, difficulties are encountered in the attachment ofthe cylinder.

The present invention has as a principal object to point out ways of producing a compressor, from sheet metal components, which is rigid and can be manufactured without assembly problems.

According to the invention, this object is achieved in that, between two substantially parallel walls, are arranged a cylindrical bushing and an up-ended support band the ends of which bear on both sides ofthe cylinder; the rest ofthe band is bent in the shape ofa ring.

This results in a very rigid latticed construction in which the cylindrical bushing, the circumferential wall portion and the support band are arranged between the parallel walls. The cylindrical bushing is thus supported on all sides, i.e. on two sides by the parallel walls and on the remaining two sides by the support band.

In a preferred embodiment of the invention, the support band is provided with external bends which form radial struts extending outwardly as far as the circumferential wall portion. These external bends or folds of the support band give increased rigidity and fix the support band, and thus the cylinder, in the correct position relative to the circumferential wall portion, so that it is possible to effect assembly without auxiliary tools at least with regard to these components. Moreover, sealed chambers are formed between the components which may serve as silencing chambers.

Support of a cylindrical bushing or sleeve is preferably ob tained by providing cylindrical recesses in the parallel walls. This reduces the required overall height of the structure outside the cylinder. Furthermore, the cylinder is thus accurately positioned relative to the parallel wall portions. Since the relative positions of cylinder, support band and circumferential wall portion are likewise accurately secured, precise positional co-ordination of all parts is ensured. It is advisable, furthermore, for the cylinder sleeve to be not only in linear, but in surface contact with the parallel wall portions.

The last-mentioned advantage may also be achieved with regard to the remaining cylinder circumference if the two ends of the support band are likewise provided with, preferably cylindrical, recesses.

The relative position of the parts can be additionally secured if one of the parallel wall portions is integral with another component. Thus, for example, the circumferential wall portion and one of the parallel wall portions may be integral with one another, so that a pot-shaped component is obtained. The other parallel wall may then be substituted by the carrying element supporting the motor, for example.

Alternatively, the two parallel walls are constructed in the form of a U-shaped sheet metal element. In this other embodiment the circumferential wall portions may likewise consist of an up-ended annular band placed between parallel wall portions. Assembly is effected simply by sliding the cylinder bushing or sleeve, the support band and the circumferential band into the U-shaped sheet metal element. Moreover, the U- shaped sheet metal element may have bent lugs for fastening the stator of the drive motor and a central depression in which a bearing can be accommodated. It thus also assumes the function of a motor-supporting element.

In some cases it may be advantageous to place the parallel ends of another up-ended, substantially annular, band between the support band and the cylinder. This inner band enables the space between the parallel walls to be subdivided into still more chambers usable as silencer chambers. Moreover, rigidity can be an extent that, at least partially, thinner sheet metal parts can be used.

The invention provides a vent, which preferably faces the motor winding, which may be provided between the walls of one of the radial bends or struts of the support band, and an oil guard may be fitted between this vent and the crank pin. Such a vent is surrounded on three sides by the support band while, on the fourth side, it is covered by the oil guard. The guard plate may be supported directly by the support band. Consequently, the vent region is not accessible to oil and cannot clog up with oil.

In another embodiment of the invention both parallel wall portions provide bearings for a drive crank shaft. Since two such parallel wall portions, at a pre-determined distance from one another, are available in the shape of a very rigid structure, they can, of course, serve as a safe support for the shaft.

The method of the invention for manufacturing a compressor of this type is characterized in that at least the support band is pre-fabricated in such a way as to contact its supports resiliently, and in that the components are brazed in this condition. If, during assembly, the support band bears resiliently on the cylindrical bushing and the circumferential wall portion, or the parallel wall portions bear resiliently on the components situated therebetween, accurate positional co-ordination is obtained, and this condition cannot be disturbed by minor vibrations. Consequently, these parts can be assembled without auxiliary tools.

It is an advantage to connect some of the parts by tack welding prior to soldering, or brazing in order to achieve the required spacing of the soldering gap.

Other features and advantages of the compressor housing according to the present invention will be better understood as described in the following specification and appended claims. in conjunction with the drawings in which:

FIG. I is the cross-section view of a first embodiment of the invention,

FIG. 2 is a section view along the section line 2-2 of FIG. I.

FIG. 3 is a cross-section view of another embodiment of the invention, and

FIG. 4 is a plan view partially in section along the line 4-4 of FIG. 3.

In the embodiment of FIGS. l and 2 a first wall portion 1 and a circumferential wall portion 2 are formed by a potshaped element 3. A second parallel wall portion 4, parallel with the first wall portion 1. forms part of a pot-shaped motor: supporting element 5. Each of the parallel walls is provided with a bearing aperture defined by projections or offsets Mind 7 respectively. Attached to the latter is a main bearing 8. The two

parallel wall portions

1 and 4 are also provided with cylindrical parts 9 and i0, bent out of the plane of the remaining wall surface.

A cylindrical bushing 11 is held between the two

parallel wall portions

1 and 4 in the region of the cylindrical portions 9 and I0 and is provided with an external flange 12. The remaining surfaces of the bushing 11 are engaged by two cylindrically shaped

end portions

13 and 14 of an up-ended support band 15. This support band is of substantially annular shape and has 3 external radial bends 16, 17 and 18 extending, in the shape of double walls, to the circumferential wall portion 2. The support band 15 is preferably pre-fabricated with a bias such that it bears resiliently on the cylindrical bushing 11 and the circumferential wall 2.

A vent-hole 19 is provided, IFIG. l, in the parallel wall portion 4 of the support element 5, within an external bend 18. its position is indicated by broken lines in FIG. 2 although it is not visible in this sectional representation. This aperture is screened, in a direction which is a direction toward the crankshaft, not shown, by a guard plate 20 which is between the two lateral walls of the radial bend 18 which assumes a clamping function. The guard plate has two

webs

21, 22 which define a venting slot 23. The upper web 21 projects radially farther toward the center than the lower web 22. This largely prevents the vent-hole 19 from clogging up with oil.

The components constituting the

various walls

1, 2, 4 and the support band 15 form four sealed silencing

chambers

24, 25, 26 and 27. From these chambers, bores or openings 28 communicate with the outside through the upper parallel wall portion 1. A channelled plate 29 covers the upper parallel wall portion 1 externally. In this channelled plate groove-like recesses 30 act as throttle ducts or passages which, in conjunction with the bores 28, connect the chambers with one another and with an antechamber 31, provided between an extentsion 32 of the channelled plate 29 and part of the circumferential wall 2. Suction refrigerant gas can enter this antechamber through an orifice 33, provided in the support element 5.

The support element is also provided with means for the attachment of a stator of a motor, not shown, and of suspension springs. However, these parts have not been illustrated because they are not relevant to the invention.

Assembly of this arrangement is effected by placing the support ring around the cylindrical bushing or sleeve 11 and both components are inserted in the pot-shaped element 3. Then the oil guard is fitted into the external bend 18. The components thus united occupy accurate relative positions, without necessitating any additional measures. This assembly may be placed upon the support element 5 from above, accurate positioning is achieved, due to the cylindrical recess 10 and the flange 12. The channelled plate 29 is added from above. its position is pre-determined by the bearing aperture 6 and by the extension 32. The main bearing 8 is attached to the support element 5 beforehand.

It becomes apparent that all essential parts of this arrangement can beassembled without the aid of tools and nevertheless occupy the proper relative positions. The structure may then be placed in a soldering oven, not shown, perhaps after ensuring correct spacing of the soldering gaps by a tack welding operation and the parts soldered togehter by solder placed in suitablesoldering positions. h k

in the embodiment of FIGS. 3 and 4, an upper parallel wall portion 34 and a lower parallel wall portion 35 are provided in the shape of a common U-shaped sheet metal element 36. The two

parallel wall portions

34 and 35 are connected to one another by a bridge 37 in the region of the cylinder end face. Cylindrical recesses defined by

portions

38, 39 are provided for accommodating a cylindrical bushing or sleeve 40.

Sleeve bearings

41 and 42 are fitted to the upper and the lower parallel wall portions.

Lugs

43, 44 are provided on both sides on the U-shaped sheet metal element 36 by bending. These lugs have fastening means, not shown, for the attachment of the stator of the drive motor and for support springs, not shown.

Between the two

parallel wall portions

34, 35 are arranged three up-ended

bands

45, 46 and 47. The band 45 is the cir cumferential wall portion. The band 46 is a support means which bears directly on the cylindrical bushing or sleeve 40 with its ends and is bent in the shape of a ring. The band 46 has outwardly radial bends or struts 48 and inwardly directed bends 49. The third band 47 is an internal band. its ends are curved cylindrically in the same way as those of the support ring 46. They are arranged between the cylindrical sleeve 40 and the ends of the support band. The remaining portions of the band 47 are ring-shaped.

The support band 46 is shaped in such a way that it bears on the circumferential wall 45 with its outward struts or bends 48, and on the internal band 47 with its inward bend 49. In this way, a number of sealed silencing chambers are formed of which the

chambers

50, 51 and 52 have been indicated in the drawing. Connection between the several chambers is by circular-arc pipe sections 53-56 which extend through and are held in the outward struts or bends 48.

Assembly is performed by, first, sliding the cylindrical bushing 40 into the cylindrical recess defined by

portions

38, 39 of the

parallel wall portions

34 and 35. Then the internal wall portions 47, the support wall 46, the pipes 53-56 and the circumferential wall portion 45 are assembled separately and inserted between the

parallel wall portions

34 and 35 from the side opposite the cylinder. Finally, the

sleeve bearings

41, 42 are fitted. Now the whole assembly can be brazed, without the individual components having to be held together by means of an auxiliary tool.

The silencing chambers may be arranged in such a way that the suction gas flows, through ports in the inner band 47 provided, for example, in the shape of serrated apertures in the band edge, into the chambers 51 and from there through the

pipes

55, 56 into the chamber 52. From the latter chamber it flows through the pipe 53 into the chamber 50 and through the pipe 54 into the opposite chamber. From the chamber 50 and the opposite chamber the suction gas may proceed to the suction valve chamber through bores situated in the plane of the cylinder end face.

While preferred embodiments of the invention have been shown and described, it will be understood that many modifications and changes can be made within the true spirit and scope of the invention.

We claim:

1. A fabricated compressor housing comprising a plurality of independently prefabricated metallic components assembled together without need of tools and fasteners into a whole comprising, a prefabricated component means defining two spaced parallel walls defining a space therebetween and a circumferential wall partially enclosing said space and having portions for defining a cylindrical recess for receiving and holding therein a sleeve, a sleeve in said recess defining in use a cylinder of the compressor, an up-ended band having radially projectingstruts disposed in said space between said parallel walls and bearing on internal surfaces of said circumferential wall dividing said space into separate chambers effective in use as silencing chambers and having a lateral extension for jointly with said wall portions defining said recess into which said sleeve is received, said parallel walls each having an opening open into the interior of said up-ended band, a bearing sleeve joined to one of said walls coaxial with the opening therein, said band comprising folds externally thereof defining said struts, and an oil guard in one of said struts, and said components being fixed in av rigid assembly free of fasteners.

2. A fabricated compressor housing according to Claim 1, in which said component means comprises two superimposed pot-shaped components comprising an upper pot-shaped component and a lower pot-shaped component, said upper component having a side wall defining said circumferential wall, and said lower component having'a depending wall spaced from and outwardly of said bearing sleeve.

3. A fabricated compressor housing according to Claim 1, including prefabricated arcuate pipes circumferentially of said band extending through and held in position by said struts providing communication into respective ones of said chambers.

4. A fabricated compressor housing according to Claim 1, in which said component means comprises a component U- shaped in vertical section defining said parallel walls.

5. A fabricated compressor housing according to Claim 4,

6. A fabricated compressor housing according to Claim 5, in which said U-shaped component comprises lugs for attachment of a motor, and a part thereof defining a central including another band defining jointly with said U-shaped 5 depresslonm which sald sleeve bearmgls fixed' component said space about said up-ended band.