US2165620A - Refrigerating apparatus - Google Patents

Description

July 1l, 1939. R. w. Dor-:G

REFRIGERATING APPARATUS 2 sheets-sheet 1 Filed Jan. 25, 1938 /aa J3 INVENTOR. IPH/.PH W. Daze, www yn ATTORNEY. l

July 1 1, 1939. R w DQEG P2,165,620

REFRIGERATING APPARATUS Filed Jan. 25, 1938 2 Sheets-Sheet 2 INVENTOR.

- PMP# M Das@ W L 1340A ATTORNEY.

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Patented July 11, 1939 UNITED STATES PATENT OFFIC REFRIGERATING APPARATUS Ralph W. Docg, Detroit, Mich., assigner to. Nash- Kelvinator Corporation,

poration of Maryland Detroit, Mich.,l a cor- This invention relates to a refrigerating apparatus, and more particularly to compressing units for use in connection :with refrigerating -apparatus. K An object of the .invention is to provide an improved lubricating system for the moving parts of the compressor and in which the vane or blade of the piston acts as a pump for delivering the lubricant through the piston to the drive shaft and its bearings for the purpose of lubricating the various operating parts. y

Another object of my invention is to provide an improved arrangement for sealing the high pressure from the low pressure side of the com- 16 pressing mechanism.

The invention consists of certain novel features of construction and combinations of parts which will be hereinafter described and pointed out in the claims.

In the accompanying drawings:

Fig. 1 is a. View in elevation showing a refrigerating system embodying the invention;

Fig. 2 is a sectional View on the line 2-2 of Fig. 1; g5 Fig. 3 is a sectional view on the line 3-3 of Fig. 2;

Fig. 4 is a detailed sectional view showing the position of the piston, eccentric, vane and rocker members in a dierent position from that disclosed in Fig. 3;

Fig. 5 is a sectional view taken on the line of Fig. 3;

Fig. 6 is a sectional View on the line 8-6 of Fig. 3 showing the valve in' elevation;

Fig.` '7 is a detailed vertical sectional view showing therelationship between the crank shaft, piston and vane; and

Fig. 8 is a detailed -sectional view'of a discharge valve. v V

Referring to v'the drawings the numeral I0 designates, in general, thefcompressor unit which withdraws evaporated refrigerant from .a' refrigerant ,evaporatorl I2 through a vapor' conduit I3, compresses "thewevaporated refrigerant. and de'- livers the same to aconden'ser |4, wherein it is liqueed'and -fromfwhichf it tis delivered lto a high-sidev oatmechanisni l5. The -float mechanism'controls the ow'of liquid refrigerant-to the evaporating4 :element 12;. The .compressor :is drivenwby a motor..l6 `through abelt traveling over aipulley l I,on the. compressor. The foperaf tionofthe motorjl andvcori1pressorf-lll` is` controlled by, a thermostaticfswitcha18s@ -yThe compressor.l .unit comprises,- in general, a casing which is formed preferably in three sections; namely, a central section 28, and'end sections 2| and 22.

The central section is provided with a tubular shaped bearing 23 in which a driving shaft 24 is journalled. The central section 20 is provided with a vertical web or parti- 5 tion 28, and formed between this partition and the end section 22 'is a lubricant chamber 29. The end section 2l is constructed in the form of a bell and is attached to the central section 20 by bolts 26, and provides a high pressure compartl0 ment 25 and housingfor a rotary pump` corri-v pressor. 3

The compressor is ofthe rotary type and consists of au cylinder block .or -l casting securely fastened to the partition or web 28 between an 15` end plate 32 and one ,side of the partition, by means of bolts 33. The cylinder blockor casting 30 has a cylindrical bore `or compression chamber 3| in which there is disposed a rotary piston 34 mounted upon an eccentric 35 formed `in) on the crank or drive shaft 24. A blade. or vane 36 is formed or connected to the piston 34.

The blade 36 nreciprocates between two semicircular rocker members 31a, which are mounted to oscillate in a cylindrical recess 38 provided v25 in the cylinder casting 30. The v.blade yis provided with a transverse slot 39 alongv its lower edge for the reception ofa coiled spring 40 (Figs."4 and 7), the ends of which are adapted to be seated in depressions .4I in the nat faces of the rocker members 31. y.'I'he spring 48 spreads the rocker members at the bottom of saidmem bers to prevent pinching or binding lthe blade or vane and at the same time affords provision for increasing the sealing` pressure at theirupper ends with theblade andthe wall ,of. the cylinf drical recess 38 to insure sealing the high pres-.- sureside of thecompressor from the .low pres-V sureside. An opening. isprovidedin the wall between chamber3l andyzlthe recess 38v through 4o Whichtheblade 36 extends into the recess .38 and between the rocker members531.

f :The -cylindrical frecess ,38 communicatesl with a longitudinal groove 42; formed lin'thecylinder casting 30 and 4extending alongvl the lbaseof the 45 recess `38 forforming an voil.;p'ort ytlierefor and I disposed. laterallyof l the vertical .-axis. of,v said .piston blade 36. vA duct`V 43 .is `formed.tlirough the cylinder casting for supplying oil, vfrom the coni- 1 -Y partment -2'5 to-the grooye ,42.andrecess 38. n 5o .-During; thezfoperatipn Ofwths;eompreSSQapth pumping .-actin withdraws-Phe .VaPQIZed Teiligerant fromthe evaporator I2 tlll'Qligh. thegvapqr .conduit 13,.;Y whence. ,it passes .through '-anci'nlet .1, opening formed in the end section 2l into the 56 filtering chamber 46, through the filtering screen 56 into the passageway 41, formed in the end section 28, to the check valve 48, and from the check valve through the passageway and intake duct 49 formed in the casting 30, delivering the gaseous refrigerant to the compression chamber 3|.

As the vaporized refrigerant is delivered to the compression chamber 3| through the port 49, the refrigerant will vbe compressed by the piston 34 through the rotation of the shaft 24, and the eccentric 35, which latter lwill cause the piston to move in a counter-clockwise direction in the chamber 3|. 'I'he compressed refrigerant is discharged from the chamber through an outlet port 5|, located in the wall of the chamber 3|, and on the opposite side of the vane or blade 36, from the duct 49. A suitable check or reed valve 52 is mounted in the recess 54 of the end plate 3'2, and communicates through the passage 55, for controlling the discharge of the. compressed refrigerant through the port 5| into the chamber 56 formed within the bell shaped housing 1| secured by bolts 12 to the face of the end plate 32. The valve 52 acts to prevent any back ow of the compresser refrigerant into the compression chamber 3|. The compressed refrigerant is discharged, with any oil that may be in chamber 56, through the tube 13 into the high pressure compartment 25. Outlet opening 95 is placed high ln the compartment 25 so as to entrap the oil in the compartment permitting only the compressed refrigerant .to pass therethrough for delivery to the condenser I4.

In the operation of the lubricating system the compressor compartment 25 is, for example, filled to the height |65 with a body of lubricating medium. The shaft 24 is provided axially thereof with an oil passage 58 and a plurality of radial passages 59 communicating with said longitudinal or axial passage 58. These radial passages 59 have communicationwith annular grooves 60 formed around the shaft 24 for delivering the lubricant to the bearing in the tubular portion 23 and the bearing of the end plate 32.

The blade 36 and the piston 34 are provided with an oil passage 66 for conducting the 'oil to a semi-circular groove 61 formed on the outer surface of the eccentric 35. A transverse passage 68 formed in the eccentric and shaft 24 leads from one end of the semi-circular groove 61 through to the axial passage 58 of the shaft 24, to the opposite end of the semi-circular groove 61. The movement of the piston 34 in the compression of the refrigerant-in the chamber 3| reciprocates and oscillates the blade 36 within the cylindrical recess 38 of the cylinder casting 30 and between the rocker 'members 31. As the rocker members 31 are oscillated by the piston 34 and vane or blade 36 in the recess 38, an edge of one of the rocker members will pass back and forth across the port or groove 42 and the rocker member will serve as a valve for cutting off the supply of oil to the recess 38. The piston and blade will function as a pump when the port 42 is closed, causing the oil collected between the rocker members and Within the passage 66 of the blade 36 to be delivered up through the passage 66 to the semi-circular groove 61 of the eccentric, and thence through the transverse passage 68 of the axial passage 58 of the shaft 24. The oil willV be forced through the axial and its radial passages'to the various bearings throughout the length of the shaft.

This is accomplished by the travel of the piston drawn in through the port 43 into the groove 42,

and up into the recess 38. When the blade 36 makes its down stroke, Fig. 4, the lubricant in the recess 38 has been cut off from the supply in the compressor compartment 25 by a rocker member 31 closing orcutting off communication between the groove 42 and the recess' 38, and the lubricant is forced 'upwardly' through the passage 66 in the blade 36 and piston 34 to the groove 61 in the face of the eccentric 35. As the eccentric 35 continues to be rotated and the semi-circular groove 61 thereof passes out of communication with the passageway 66 of the blade and piston, the lubricant contained in the transverse passage 68 and groove 61 will drain into the axial passage 58 of the shaft 24.

The travel of the piston 34 counter-clockwise in the chamber 3| causes the blade 36 to be moved up and down between the two semi-circular rockers 31. As shown in Fig. 3, the blade has begun to move upwardly and is now drawing oil by suction through the duct 43 and port 4,2v into the recess 38 and as the piston continues to move, the blade is elevated, causing the rockers to be oscillated until one of the rocker members will pass over the port 42 and cut olf communication from the lubricant in the high pressure compartment with the cylinder recess 38, so that on the down stroke of the piston this confined lubricant will be forced upwardly through the passage 66 in the blade 31. Of course, in this downward movement of the piston the rocker members 31 are oscillated and the rocker member which has been covering the port 42 will be moved, causing the port to be uncovered prior to the next up stroke of the piston and communication re-established withl the cylinder recess 38. It will, therefore, be noted that the rocker member is adapted to pass over the port 42 for establishing and cutting off communication between the high pressure compartment 25 and 'recess 38, and thereby functioning as a valve controlled by the reciprocation of the blade 36.

Mounted upon the shaft.24 adjacent the end plate 32 is a y wheel or counterweight 10. The end of the shaft and counterweight are preferably enclosed within the housing 1|. The oil fiowing through the axial passage 58 is delivered to the bearing of the plate 32, and to the thrust bearing 14 interposed therebetween and the counterweight 10. The end of the passage 58y is plugged, as at 15. 'I'he surplus oil on the bearing will be collected in the chamber 56 to beiconducted therefrom by means of a tube 13 which has one end thereof located near the bottom of the chamber 56, and the other end extending through the housing 1| opening in to the high pressurechamber 25. Due to the pressure of the compressed gas entering the chamber 56 the oil will be forced out ahead o f the gas through the tube 13 into the compartment 25. 'I'he tube 13 is so positioned within the housing as to be able to drain nearly all of the oil that may collect therein 'during the operation of the compressor.

It will beV apparent that lubricant is distributed to the various parts and bearings under force feed by the reciprocation of the blade or vane 36.' Provided in the system is a sleeve valve serv- -ing a dual purpose of maintaining a constant oil pressure and also as an unloading valve for relieving the compressor of work during thc beginning of operations until suicient speed is developed in the motor |6 to produce the required torque for operating the compressor. Referring to Figs. and 6, oil is delivered from the axial passage 58 through a radialpassage 59 to a passage 8| formed in the end plate 32. The cylinder block 38 is provided with a transverse bore 82 in which is disposed the sleeve valve 88, held against its seat 83 formed in the end plate 32, by a coiled spring 84. The spring 84 has one end thereof received in the sleeve of the valve and its other end bearing against the partition 28. A port 85 is formed in the seat 83 which forms a communication between the passage 8| and the bore 82. The bore is provided with a port 86 to allow the oil to return to the lubricant or high pressure compartment 25. The valve seat 83 is recessed or grooved, as at 8l to allow a permanent `bleed or seepage around the valve 88 to permit its full return during the idle period of the compressor. When the compressor is operating at maximum speed the-pressure in the system will be suicient to move the sleeve 88 rearwardly against the spring 84, opening fully the port 86 for a complete cycling of the oil through the system.

Formed in the face of the cylindrical casting 38 is a groove 98 cooperating with the face of the partition 2,8 to form a passageway that opens into, at approximately near the top of the high compression compartment 25, and leads into the rear of the bore or cylinder 82. Drilled in the casting 38 is a passage 9| that opens into the cylinder 82 at a point rearwardly to the sleeve valve 88 when it is in abutment with its seat 83.

'I'he passage 9| communicates at its opposite end A with a second passage 92 leading into the port 49 across the back side of the valve 48.

Before and during the initial starting period of thecompressor, the sleeve valve 88 will be in abutment against its seat 83, permitting refrigerant to flow from the chamber into the compression chamber 3|, through the passage 90" into cylinder 82, entering passage 9|, into 92, and to the inlet port 49. Thus the compressor is drawing the high pressure refrigerant, during the initial starting period, from the compartmentl 25 and discharging it back through the port 5|, passage 55, past reed valve 52 into chamber 56, into the pipe 13 and out into the high pressure compartment 25, thereby accomplishing no work,

l merely permitting the motor I5 to gain its operating torque. As the speed of motor and compressor increases, the oil pressure rises until near the maximum speed the oil pressure will be sufcient to move rearwardly the sleeve valve 88 to cover the opening ofthe passageway 9|, interrupting communication with the groove 98. Thereupon the compressor will draw the low pressure gaseous refrigerant from the evaporator |2 through the connection of conduit I3, opening 45, filtering chamber 45, passage 41, through check valve 48, into the port 49. The refrigerant after compression will be discharged through the already described route from exhaust port 5| into chamber 25. The pump blade 36 is so designed as to maintain a sulcient pressure of oil against the face of the sleeve valve 88 to hold it over the passage 9| during the operation of,:or cycling of the refrigerating system.

The lubricant chamber 29 has communication with a chamber 95 formed in the end of the tubular bearing 23 by means of an oil duct 96 formed in the end plate 22. Surrounding the shaft 24 and located within the chamber 95, is a spring control expansive seal 91, one end of this seal being attached to a disk 98, interposed between the end plate 22 and section 28, whereas the other end of the seal bears against a shoulder 9,9, formed on the shaft 24. A passage 88 communicates with chamber 95 and the suctionport 49 to maintain the seal under low or suction pressure of the compressor.

A suitable packing |A0| is mounted on the shaft 24 adjacent the end section 22 which packing is held in place by a coiled spring |82 encircling the shaft and bearing at one end against the pulley This packing and sleeve functioning as a stuffing box to prevent the seepage of lubricant through the end section 22. Some of the oil collected in the chamber 95 of the bearing 23 is conducted therefrom through the passage |88 to the intake port 49 where it will commingle with the refrigerant' as it passes the check valve 48. A baflie plate |83 permits only the overflow to pass down through the passage |88.

Although only a preferred form of the invention has been illustrated, and that form described in detail, it will be apparent to those skilled in the art that various modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims.

I claim:

1. In a compressor, comprising a cylinder having a compression chamber, a gyrating piston in said compression chamber, said cylinder provided with a'passage having communication with the compression chamber, a piston blade mounted in said passage and adapted to-be reciprocated in said passage by said piston in its movement in said chamber, said piston blade being problade, and a rocker mounted in said cylinder passage and at one sideof said blade to act as a valve for said oil inlet, said blade on one stroke draw- 'ing lubricant into the cylinder passage and on another'stroke oscillating the rocker to close the oil inlet and allowing said blade to force the lubricant into the compressor. t

2. In a compressor, comprising a cylinder having a compression chamber, a gyrating piston in said chamber, a shaft having an eccentric for operating the piston, said shaft and eccentric having lubricating passages in associated relation, a piston blade reciprocated by the movement of the piston and having a lubricant passage adapted to deliver lubricant to the passages of the shaft and eccentric, said cylinder havingv a passage in communication with said chamber and in which the piston blade reciprocates, said cylinder having an oil inlet communicating 4with said cylinder passage and 0H- set with respect to the vertical axis of said blade, and a rocker mounted in said cylinder passage and at one side of said blade to act. as a valve for said oil inlet, said blade on its upstrokeoscillating the rocker to open the inlet Y passage of the blade and into the passages of the shaft and eccentric.

3. In a compressor, comprising a cylinder having a compression chamber and a gyrating piston in said chamber, a pistonblade connected to the piston and adapted to be reciprocated in the travel of the piston, said cylinder having a recess in communication with said chamber, said cylinder having an oil inlet communicating with said recess for the admission o f lubricant thereto and disposed laterally of the vertical axis of said piston blade, rockers mounted in said recess and between which rockers the piston blade reciprocates, one at least of the rockers functioning as a valve for said oil inlet, resilient means interposed between said rockers to prevent binding on the blade and for increasing the sealing pressure at their upper ends with the blade, said blade on its upstroke oscillating the rockers and permitting lubricant to be drawn into the recess and on its downstroke moving one of the rockers to close the oil inlet for cutting off the supply of lubricant to the recess and causing the confined lubricant to be ejected by said blade into the compressor.

4. In a compressor, comprising a cylinder having a compression chamber and a gyrating piston in said chamber, a shaftl having an eccentric for operating the piston, said shaft and eccentric having lubricating passages in associated relation, a piston blade reciprocated by the movement of the piston and having a lubricant passage adapted to deliver lubricant to the passages of the shaft and eccentric, said cylinder having a passage in which the piston blade reciprocates, said cylinder having an oil inlet communicating with said cylinder passage and disposed laterally of the vertical axis of said blade, and rockers disposed in said cylinder passage and on opposite sides of said blade, one at leastl of the rockers functioning as a valve for said oil inlet, said blade on its upstroke oscillating the rockers to open the oil inlet for permitting the lubricant to be drawn into the cylinder passage, and on its downstroke operating one' of the rockers to close the oil inlet to permit said blade to force the lubricant conned in the cylinder passage through the passage of said blade and into the passages of the shaft and eccentric. y

5. The combination-of a compressor including a cylinder and a gyrating piston, a piston blade adapted to be reciprocated in the travel of the piston, said cylinder having a passage in which the blade reciprocates, said passage provided with an oil inlet port for the admission of lubricant thereto, and a rocker member disposed along one side of the passage and blade for guiding the blade and acting as a valve for opening and closing said inlet port, said blade on its upstroke operating the rocker for opening the inlet port and allowing oil to be drawn into the passage and on the downstroke of the piston moving the rocker to close the oil port and permitting said blade to pump the oil out of said passage into the compressor.

6. The combination of a compressor including a cylinder having a compression chamber and a gyratory piston in said compression chamber, a piston blade connected to the piston and adapted to be reciprocated in the travel of the piston, said cylinder having an intake port and an outlet port leading to said compression chamber and disposed respectively on opposite sides of said piston blade, said cylinder having a recess in communication with the chamber, rockers mounted in said recess and between which the piston blade reciprocates and resilient means interposed between said rockers and beneath said piston blade to prevent the rockers binding on the blade and for increasing the sealing pressure at their upper end with the blade.

RALPH W. DOEG.

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