US3075686A

US3075686A - Refrigerating apparatus

Info

Publication number: US3075686A
Application number: US697575A
Authority: US
Inventors: William K Steinhagen
Original assignee: Motors Liquidation Co
Current assignee: Motors Liquidation Co
Priority date: 1957-11-20
Filing date: 1957-11-20
Publication date: 1963-01-29
Anticipated expiration: 1980-01-29

Description

Jan. 29, 1963 w. K. STEINHAGEN 3,075,686

REFRIGERATING APPARATUS Filed Nov. 20, 1957 3 Sheets-Sheet l V INV ENT OR.

ll [Ilium A. Szeinbgyen HIS ATTORNEY Jan, 29, 1963 w. K. STEINHAGEN 3,075,686

REFRIGERATING APPARATUS Filed Nov. 20, 1957 3 Sheets-Sheet 2 INVENTOR. ll/illian [If Sleinhgyen H IS ATTORNEY Jan. 29, 1963 w. K. STEINHAGEN 3,075,686

REFRIGERATING APPARATUS 3 Sheets-Sheet 3 Filed Nov. 20, 1957 INVENTOR. William K. Szeinba HIS ATTORNEY United States Patent Ofifice 3,075,686 Patented Jan. 29, 1963 3,075,686 REFRIGERATING APPARATUS William K. Steinhagen, Royal Oak, Mich, assignor to General Motors Corporation, Detroit, Mich, a corporation of Delaware Filed Nov. 20, 1957, Ser. No. 697,575 2 Claims. (Cl. 230-58) This invention relates to refrigerating apparatus and more particularly to a sealed motor-compressor unit.

It is an object of this invention to provide an improved arrangement for varying the stroke of a reciprocating compressor by means of a double eccentric arrangement.

It is customary to manufacture refrigerators of various sizes and to equip the different sized refrigerators with a compressor of a size suitable for each refrigerator and this usually necessitates manufacturing a number of different size compressors. It has been the usual practice to accomplish this result by changing either the bore or stroke or both of the compressor and changing many associated parts whereby these parts are not usable in more than one size compressor. It is an object of this invention to keep as many parts as possible completely interchangeable among the various size compressors so that except for the motor it is only necessary to change the size of a spacer which determines the clearance between the piston and the cylinder head.

Further objects and advantages of the present invention will be apparent fro-m the following description, reference being had to the accompanying drawings, wherein a preferred form of the present invention is clearly shown.

In the drawings:

FIGURE 1 is a vertical sectional view showing a preferred embodiment of the invention;

FIGURE 2 is a horizontal sectional view taken substantially on line 22 of FIGURE 1;

FIGURE 3 is a vertical sectional view taken substantially on the line 3-3 of FIGURE 1;

FIGURE 4 is a fragmentary vertical sectional view taken substantially on line 4-4 of FIGURE 1 and showing the suction valve arrangement;

FIGURE 5 is a fragmentary sectional view taken on line 5-5 of FIGURE 1 and showing one possible arrangement of the dual eccentrics for maximum stroke of the piston;

FIGURE 6 is a view similar to FIGURE 5 but showing another possible arrangement of the dual eccentrics which would give a minimum piston stroke;

FIGURE 7 is a fragmentary end elevational view showing the construction of the cylinder head cover plate;

FIGURE 8 is a fragmentary sectional view taken substantially on the line 8-8 of FIGURE 3 and showing the discharge reed valve; and

FIGURE 9 is a fragmentary sectional view on an enlarged scale showing in somewhat exaggerated manner the curvature of the piston.

Referring now to the drawings wherein a preferred embodiment of the invention has been shown, reference numeral 10 designates an inverted cup-shaped casing element which in cooperation with an end plate 11 forms a sealed motor-compressor housing. The end plate 11 is in the form of a sheet metal stamping having upwardly extending embossed portions 12 which serve as seats for coil springs 14 used in supporting the motor-compressor mechanism within the main housing 10.

The motor-compressor mechanism includes a stamped sheet metal frame element 16 which has brazed or otherwise secured thereto a plurality of U-shaped stampings 18 to which there are secured spring engaging studs 20 as best shown in FIGURE 1. The studs 20 project on into the springs 14 so as to position and support the motorcompressor unit within the main casing. The stamped sheet metal frame element 16 has secured thereto a sheet metal sleeve element 24 which serves to support a cast iron bearing sleeve 26 in which the main drive shaft 28 is journalled. A conventional motor stator 30 is held in place on the stamped frame element 16 by means of a cylindrical sheet metal stator supporting ring 32 which is secured to the frame 16.

A motor rotor assembly 34 is secured to the upper end of the shaft 28 through the medium of the sleeve element 36. The upper end of the motor rotor 34 is provided with integrally formed fan blade elements 38 which are cast as integral parts of the usual rotor end ring. The lower end of the shaft 28 is provided with an eccentric portion 40 which is smaller in diameter than the main portion of the shaft 28. This reduced end portion 40 serves to support a ring-like .element 42 having an eccentric aperture through which the eccentric portion of the shaft 40 projects so as to form therewith a double eccentric. The element 42 has a press fit on the portion 40 so as to prevent relative rotation of the parts after they have been assembled in the desired relationship. The ring-like element may be assembled onto the eccentric end portion 40 of the main drive shaft in any of many relative positions whereby it is possible to obtain many different overall effective eccentricities without changing the size of the individual parts. Thus it is possible to obtain different length piston strokes and therefore different compressor capacities by changing the relative position of the parts when the parts are first assembled.

A ring 44 is rotatably mounted on the outer periphery of the eccentric portion 42 and is adapted to engage the one end member 50 of a piston assembly generally designated by the reference numeral 52. There is a slight curvature on the end member 50 so as to eliminate the need for squareness or alignment. The ring 44 which is free to rotate on the eccentric portion 42 engages the curved surface on the member 50 with a rolling action so as to reduce the wear on the engaging surface. The piston assembly 52 includes a substantially cup-shaped sheet metal stamping 54 which is brazed or otherwise secured to the thrust member 50 as best shown in FIG- URES 1 and 2.

The piston element 54 is sliclably supported within a fixed cylinder element 56 carried by and secured to the sheet metal frame elements 16 by means of bolts 57. A coil spring 55 is provided between end plate 50 of the piston assembly 52 and a shoulder 59 provided on the cylinder element 56 so as to bias the piston assembly towards the eccentric on the main drive shaft. By virtue of the above described arrangement, rotation of the drive shaft 28 will cause the eccentrically mounted ring 44 to actuate the piston assembly. A valve plate 61 having an inlet port 64 and an outlet port 65 closes the one end of the cylinder element as shown. The gas to be compressed enters the housing 10 through the suction line 58 which enters the housing 10 as best shown in FIGURE 1.

A sheet metal deflector element '60 is provided as shown adjacent the inlet line 58 so as to largely prevent intermingling of the relatively cold incoming refrigerant vapor and the relatively hot refrigerant vapor surrounding the motor. A conduit 62 directs the incoming refrigerant downwardly to the suction inlet 64 leading to the compression chamber Within the cylinder element 56.

A reed type valve plate 70 is provided between the valve plate 61 and the end wall of the cylinder 56. This valve plate is best shown in FIGURE 4 and includes an inlet valve reed portion 72 which serves the usual function of an inlet valve. A reed valve 74 (see FIGURE 8) is provided for controlling the flow through the discharge port 65 in accordance with well known practice. A

stamped" sheet metal plate 76 is brazed to a plate element 78 and this assembly is held in place as best shown in FIGURE 1 against the valve plate 61. The gas to be compressed is supplied to the compression chamber through the conduit 62' which leads. to the suction port 64 and the compressed gas is delivered into a muffier chamber 80 via a passage 82 formed between the embossed metal plate. 76 and the plate element 78. The gas. leaves the. mother chamber through the outlet line 84.

When each compressor is first assembled the relative position of the eccentric ring-like portion 4 2 on the eccentric portion 40 of the drive shaft will be fixed so as to provide the desired piston. stroke for a compressor of a given desired output rating. The desired head clearance in the compression chamber for any given length of stroke is obtained by selecting a spacer or shim element 90 having a thickness which will establish the desired relationship between the shaft 28 and the cylinder head which in this case includes the valve plate 61 and associated parts.

In this manner it is possible to make compressors of several different capacities, all of which use the same basic compressor parts except for the thickness of the spacer shim 90.

While the form of embodiment of the invention as herein disclosed constitutes a preferred form, it is to be understood that other forms might be adopted, as may come within the scope of the claims which follow.

What is claimed isas follows:

1. In a sealed motor-compressor unit, an inverted cupshaped stamped sheet metal casing, a stamped sheet metal base plate for closing the open end of said casing, said plate having a plurality of inwardly embossed spring seats formed thereon, a motor-compressor assembly disposed within said casing, said assembly including a stamped sheet metal frame element, spring seats carried by said stamped frame element and arranged substantially in vertical alignment with said embossed spring seats, spring members disposed between said vertically aligned spring seats, said stamped sheet metal frame element having secured thereto a bearing element, a shaft rotatably disposed within said bearing element, a motor including a rotor secured to one end of said shaft, said shaft having an eccentric portion formed thereon, ring means disposed on said eccentric portion, said ring means having an aperture through which said eccentric portion projects, said aperture being offset from the center of said ring means, said ring means having a press fit on said eccentric portion whereby the relativeposition of said ring on said eccentric portion. when assembled determines the overall effective eccentricity of the outer periphery of said ring means, cylinder means carried by said frame element, a reciprocating piston operated by said eccentric portion and dis posed within said cylinder means, said piston including a portion arranged to directly engage said ring means so as to be reciprocated thereby.

2. In a sealed motor-compressor unit, a sheet metal casing, a motor-compressor assembly disposed within said casing, said assembly including sheet metal frame means,- said frame means including a shaft bearing, a shaft rotatably disposed within said bearing, a motor including a rotor secured to one end of said shaft, said shaft having an eccentric portion formed thereon, ring means disposed on said eccentric portion and held thereon in any one of several possible relative positions of said eccentric portion and said ring means, said ring means having an aperture through which said eccentric portion projects, said aperture being offset from the center of said ring means, cylinder means carried by said sheet metal frame means and including a compression chamber, a reciprocating piston means disposed within said chamber, said piston means including a portion having a slightly curved cam surface arranged to. directly engage said ring means so as to be reciprocated thereby, means for positioning said cylinder means in a predetermined relationship. relative to the central axis of said shaft, said last named means comprising a shim between a portion of said frame means and a portion of said cylinder means for establishing the distance between the end of said compression chamber and the center of rotation of said shaft. 8

References Cited in the file of this patent UNITED STATES PATENTS 1,026,132 Thompson May 14, 1912 1,091,496 Fox Mar. 31, 1914 1,761,429 Dean June 3, 1930 1,772,667 Hvid Aug. 12, 1930 1,901,817 Neidl Mar. 14,1933 2,040,667 Moulet May 12, 1936 2,312,057 Williams Feb. 23, 1943 2,328,420 Brown et al Aug. 31, 1943 2,414,003 Thompson Jan. 7, 1947 2,472,355 Whittingham June 7, 1 949 2,500,751 Halvarson Mar. 14, 1950 2,587,246 Touborg Feb. 26, 1952 2,592,237 Bradley Apr. 8, 1952 2,622,788 Ramclow Dec. 23, 1952 2,693,150 Pickard et al. Nov. 2, 1954 2,766,929 Rusch et al Oct. 16, 1956 2,783,615 Gooch et al Mar..5, 1957 2,823,850 Hintze Feb. 18, 1958 2,842,284 Flick July 8, 1958 2,945,451 Griswold July 19, 1960 FOREIGN PATENTS 600,415 Great Britain July 6, 1946 505,533 Belgium Aug. 30, 1951 567,840 Canada Dec. 15., 1953 1,126,864 France Dec. 3, 1956 OTHER REFERENCES German application KL 59a35, P-11,505, August 9, 1956.

Claims

1. IN A SEALED MOTOR-COMPRESSOR UNIT, AN INVERTED CUPSHAPED STAMPED SHEET METAL CASING, A STAMPED SHEET METAL BASE PLATE FOR CLOSING THE OPEN END OF SAID CASING, SAID PLATE HAVING A PLURALITY OF INWARDLY EMBOSSED SPRING SEATS FORMED THEREON, A MOTOR-COMPRESSOR ASSEMBLY DISPOSED WITHIN SAID CASING, SAID ASSEMBLY INCLUDING A STAMPED SHEET METAL FRAME ELEMENT, SPRING SEATS CARRIED BY SAID STAMPED FRAME ELEMENT AND ARRANGED SUBSTANTIALLY IN VERTICAL ALIGNMENT WITH SAID EMBOSSED SPRING SEATS, SPRING MEMBERS DISPOSED BETWEEN SAID VERTICALLY ALIGNED SPRING SEATS, SAID STAMPED SHEET METAL FRAME ELEMENT HAVING SECURED THERETO A BEARING ELEMENT, A SHAFT ROTATABLY DISPOSED WITHIN SAID BEARING ELEMENT, A MOTOR INCLUDING A ROTOR SECURED TO ONE END OF SAID SHAFT, SAID SHAFT HAVING AN ECCENTRIC PORTION FORMED THEREON, RING MEANS DISPOSED ON SAID ECCENTRIC PORTION, SAID RING MEANS HAVING AN APERTURE THROUGH WHICH SAID ECCENTRIC PORTION PROJECTS, SAID APERTURE BEING OFFSET FROM THE CENTER OF SAID RING MEANS, SAID RING MEANS HAVING A PRESS FIT ON SAID ECCENTRIC PORTION WHEREBY THE RELATIVE POSITION OF SAID RING ON SAID ECCENTRIC PORTION WHEN ASSEMBLED DETERMINES THE OVERALL EFFECTIVE ECCENTRICITY OF THE OUTER PERIPHERY OF SAID RING MEANS, CYLINDER MEANS CARRIED BY SAID FRAME ELEMENT, A RECIPROCATING PISTON OPERATED BY SAID ECCENTRIC PORTION AND DISPOSED WITHIN SAID CYLINDER MEANS, SAID PISTON INCLUDING A PORTION ARRANGED TO DIRECTLY ENGAGE SAID RING MEANS SO AS TO BE RECIPROCATED THEREBY.