US2136097A - Refrigerating apparatus - Google Patents

Description

Nov. 8, 19. I 1.. H. BROWNE 4 2,136,097

REFRIGERATING APFARATUS Filed Aug. 8, 1956 4 Sheets-Sheet 3 1 INVENTOR L i ndsa 51H Brawn.

ATTORNEYS Nov. 8, 1938,

L. H. BROWNE 2,136,097

REFRIGERATING APPARATUS Filed Au 8, 1936 4 Sheets-Sheet 4 ATTORNEYS Patentefd Nov. 8, 1 938 UNITED STATES PATENT. OFFICE 2,136,097 i nnrnrcnnarmc APPARATUS Lindsay H. Browne, Pittsford, N. Y., assignor to Kellogg Compressor and Manufacturing Corvporation, a corporation of New York Application August 8, 1936, Serial No. 94,929

2 Claims. (01.32-115) This invention pertains to improvements in refrigerating apparatus.

An object of the invention is to provide improved apparatus forming a closed refrigerating system.

Another object .is to provide a closed refrigveration .system' including improved silencing means. 1

Another object is to provide an improved high side or condensing unit. l

Another object is to provide a device of the above character including an improved unitary motor-compressor structure.

A further object is to provide improved 'sealing means between the motor and compressor.

Another object is to provide improvedcompressor valve structures.

Another object is to provide an improved cylinder headstructure and improved means for securing the head, discharge valve plate and cylinder together. w

A further object is to provide an improved resilient mounting for the high side apparatus.

A still further object is to provide a high side unit of the above type which is compact, simple and cheap to manufacture and which maybe readily adapted for difierent types of installation.

Other objects'and advantages of the invention ailwill become apparent during the course of the following description in connection with the accompa'nying drawings, in which- 1 Figure 1 is a side view of a preferred form of the invention, partly in section;

36 Figure 2 is an end elevation of the same;

Figure 3 is an enlarged detail sectional view showing the seal, shaft and crank structures;

Figure 4 is a detail end elevation of the bearing bushin 4o Figure 5 is a cross sectional view ofpthe discharge valve and plate showing the valve in open position;

Figure 6 is a similar view showing the valve in closed position;

Figure 7 is a plan view of the same;

Figure 81a adetail view showing the discharge mufller in longitudinal section together with its terminal connecting means;

Figure 9 is anpend elevation of the muflier:

Figure 101s a detail sectional view of the piston structure and upper end of the connecting rod;

Figure 11 is an end elevation 'of the condensing unit showing an alternative arrangement of the compressor;

Figure 12 is a diagrammatic representation of a closed refrigeration system including the apparatus; and

Figure 13 is a detail sectional view of an alternative shaft and seal structure.

Referring to Figures 1 and 2, the numeral indicates a base which may be provided with springs 2| to form a resilient mounting for the condensing or high side unit. Brackets 22 and 23 are secured to the base 29 and form a support for the motor-compressor assembly in a manner to be hereinafter described.

An electric motor 24 comprising an outer shell ing 28 containing a suitable bearing rotatably supporting one end of a'shaft 29 on which is mounted the rotor 30. A unitary compressor block 3| comprises an end'plate portion 32, a

v carrying the usual stator coils 26, has a rear end plate 2'! on which is formed a bearing houscrank case portion 34, and a cylinder 35. The end plate portion 32 is secured to the motor shell 25 in the manner common to electric motor construction, as, for example, by bolts 33, Figure 2.

A sleeve 36 is disposed on a reduced extension 31 of the motor shaft 29 and forms a journal rotatably mounted in a bearing bushing 38 secured in a boss 39 extending from the crank case 34 toward the motor 24.

A crank member 40 is screwed on the threaded end 4| of the extension 31, clamping the sleeve 36 longitudinally against a collar 42 which in turn presses against a gasket 42a. backed by a shoulder 29a on the shaft 29. A metallic bellows on a flange 44 which is clamped against a gasket 44a on the end of the boss 39 by means of an internally shouldered nut 45 screwed on the threaded periphery of the boss.

- A ring 46 secured to the end of the bellows 43, as shown in enlarged detail in Figure 3, carries an annular, shoe 4! engaging the face of the collar 42.- A compression spring 48 disposed between the flange 44 and the ring 46 urges the shoe 4! into engagement with the collar 42 as noted, the mean diameter of the shoe face in contact with the collar being substantially the same as that of the bellows 43. The nut 45 has formed thereon a slotted cylindrical extension 49 slidably engaging the outer circumference of the ring 46 and adapted to maintain the latter and its shoe 41 in concentric alignment with the shaft 29 and collar 42.

. An oil hole 50, Figure 3, leads from a pocket 5| formed in the crank case 34. above the shaft an intersecting helical oil groove 53 in the bushing 38.

Referring to Figure 4, a longitudinal slot or groove is formed in the outer circumference of the bushing 38 and extends throughout the full length thereof, the groove 54 being located near the top of the bushing.

The crank member 40 carries a crank pin 55, Figures 1 and 3, a counterweight 56 being attached to the crank member 40 opposite the crank pin. A piston 51, Figures 1 and 10, of a type fully described and claimed in copending application Serial No. 94,930, filed August 8, 1936, is slidably disposed in the cylinder 35 and comprises an outer. barrel 58 in which a trunnion member 59 is fastened by means of a screw 80 through the head SI of the barrel. A wrist pin 82, in the trunnion member 59, has rockably mounted thereon the bushed upper end 63 of a connecting rod 84. The lower end of the connecting rod is equipped with a bushing 66 rotatably mounted on the crank pin 55. A downwardly extending oil splasher 61 is fastened to the lower end 65 of the connecting rod. The piston barrel 58 is provided with annular oil grooves 58a in its periphery to aid in proper lubrication of the cylinder wall and to maintain a seal against leakage of gas past the piston.

An annular discharge valve plate 68 has a lower cylindrical portion 69 extending into the top of the cylinder 35. An upper cylindrical portion I of the valve plate 68 fits into a chamber 'II of the cylinder head 12.

Referring to Figure 2, it will be seen that a yoke 13 is disposed across the top of the cylinder head 12. Apair of links I4 and 15 are pivoted to lugs I6 by means of pins IT on the crankcase 34 and are also articulated to the end of the yoke I3 by means of pin 18. A screw 19, threaded through the middle of the yoke I3, has a concave lower end 80 bearing on a ball 8| sunk into the top of the head I2 above the center line of the cylinder 35 as shown in Figure 1. When the screw I9 is screwed downward in assembly, the valve plate 68 is firmly clamped between the head 12 and cylinder 35, sealing gaskets 82 and 83 being provided respectively above and below the plate.

It will be seen that the use of the floating yoke I3 and the clamping screw I9 bearing on the central ball 8I provides a firm and even pressure on the clamped surfaces of the head 12, plate 88 and cylinder 35 and eliminates the use of the usual cylinder head bolts, thereby making possible a simple structure and facilitating assembly while at the same time assuring tightness of the gaskets.

The extension of the plate 68 into both the cylinder 35 and the head 12 assures concentricity of these parts and also assists in maintaining tightnessof the gaskets 82 and 83, as no edges of the later are exposed directly to internal pressure.

The crank-case 34 has an opening 84 through which the internal working parts may be inserted during assembly. A closure plate 85' coverlng the opening 84 is secured to the crank-case 34 by means of cap screws 88. An annular extension 81 of the closure plate is inserted in a ring 88 of rubber or other suitable resilient material secured to the bracket 23 by means of a clamp 89, as shown in Figure 2. A similar resilient ring 90, Figure l, is clamped to the bracket 22 and concentrically supports the rear end of the motor 24.

It will be seen that the similar rings 88 and 90 and their brackets 23 and 22 provide a concentric resilient mounting for the motor-compressor unit on the base 20.

The suction and discharge valve structures of the compressor are as follows:

Referring to the enlarged sectional view of the piston Figure 10, it will be seen that the head 6| of the barrel 58 has formed in its upper face an annular groove 9i from which holes 92 lead downward into the interior of the barrel. A suitable bafile I36 is provided in the lower part of the barrel 58 to prevent excess oil from being splashed into the holes 92. A ring plate valve 93 of this metal is retained on the upper face of the piston by the head 94 of the screw 60, the ring plate acting as a closure over groove 9i. A narrow washer 95 of thickness slightly greater than the ring plate 93, is clamped under the screw head 94 within the ring plate and acts as a spacer. During the downward or suction stroke of the piston, the entire ring plate 93 is allowed a slight upward movement under the screw head 94 to permit the passage of vapor through the holes 92, groove 9I and around the periphery of the ring plate. By this means, an ample annular area is provided for free entry of gas to the cylinder, but due to the lightness of the ring plate and its restricted movement, the suction valve operation is performed without noise.

The discharge valve plate 88, Figures 1, 5, 6 and 7, has formed in its lower surface a depression 96 to accommodate the screw head 94 when the piston is as the top of its stroke, thereby permitting the clearance space to be held to a minimum. The flat upper face I00 of the plate 68 has formed therein an annular groove 91 surrounding the central discharge passage 98. A cantilever leaf valve 99 is secured at one end to the upper face I00 by means of the screw IOI, with its other end overlapping the discharge passage 98. A laterally tapered limiting spring finger I02 is fastened to the plate 88 by means of a screw I83 diametrically opposite the screw WI and is spaced from the plate by an underlying washer I04.

The spring finger I02 is bent downwardly throughout part of its length and terminates in a downwardly convex end portion or tip I engaging thetop of the valve leaf 99 in line with the discharge passage 98.

It will be understood that the thickness of the leaf valve 99 and the limiting spring finger I 02 is exaggerated in Figures 5 and 6 for purposes of clarity, their actual thickness being very small.

During the compression stroke of the piston, compressed gas or vapor is forced upward through the passage 98. The pressure against the lower face of the leaf valve 99 raises the latter from its seat I06 defined by the grooves 91 and central passage 98, allowing gas to pass upward into the discharge chamber II. As the leat valve 99 is raised it flexes the finger I02 by forcing the latters forward end upward. As

valve 99 continues to rise, its line of contact with finger I02 shifts to the right, Figures 5 and 6,

as the comparatively narrow bent portion of I02 tends to flatten upward. This shifting to the right of the line of contact occurs with a substantially rolling action as. the two leaves flex together and results in increasing resistance to the rise of the valve 99 due both to the shortening of the effective cantilever length of finger .tion from left to The above action continues until at extreme openposition the valve leaf 99 and finger I02 mutually form an arch as shown in Figure 5. when discharge is completed the reverseaction occurs, the two leaves flexing downward with a substantially rolling contact until leaf 99 engages its seat I06, the contact between leaf 99 and seat I06 also occurring with a slight rolling moright as the leaf loses its upward curvature. The end'portion I05 of finger I02 holds the leaf 99 lightly but firmly and evenly on its seat while the valve is in closed position, due to the fingers pressure on the leaf directly above the center of the discharge passage 90.

While the actual arnplitude of valve rise during discharge is very small, the above interaction of the parts has been described indetail because together with the small inertia of the parts, it results in positive and quiet valve action at'the comparatively high compressor speed provided by the directly connected motor, at the same time permitting discharge of the gas with a. minimum of resistance. 1

The cylinder head 12, Figure 1, has alateral discharge shut-ofl valve I00, Figures *1 and 2,'of suitable type provided with the usual sealing cap I09.

A muiller or silencer H0, shown in detail in Figure 8 comprises an outer shell III enclosing a chamber ,2. A tubular member H3, extending into the chamber I I2, has a flange I I4 secured to the outer shell III and forming one end of the silencer. The tubular member II3 has in its barrel a number of perforations H5 and is closed at its inner end, the outer end thereof being connected to the outlet H 01 the discharge shut-oil valve I08. A tubing union elbow II'I screwed into the end of the shell III, forms the outletfrom the chamber II2.

From the union II'I a tube H8 leads to an aircooled condenser H9 secured to the base 20 beyond the end of the motor 24. A fan I20 on the rear end of the shaft 29 adjacent the con denser H9 is adapted to furnish the latter with a draft of cooling air when the device is in op eration. From the bottom of theicondenser 9 a liquid tube iii leads through a union H22, Fig-1 ure 1, into a suitable receiver M3 fastened to the "base it by means of brackets 526 as shown in Figure 2.

Thereceiver @23 is provided with a liquid outlet stop valve 62%?) adapted to be connected .in the usual manner to any suitable type of cooling unit or low side such as thatshown diagrammatically in Figure 12 and including the expansion valve it? and cooling coil H9. The valve 6'25 carries an inlet tube 826, Figure 2, extending downward inside the receiver 623 to a point near the latters bottom -A suction shut-01f valve I21! of anysuitable type secured to the crank case 33 and leading into the interior thereof is adapted to be connected to return end 02 the cooling coil or unit 838 as also illustrated in Figure 12.

V A bracket are, fastened to the outer shell 20 of motor it, supports an oil tube I29 leading to the rear bearing housing 28 and provided with a closure cap 536. The provision for applying oil to the motor bearing is thus located at a point remote from the fan I20 and man easily accessible position. The bracket I20 may be provided with a loop I adapted to support a capacitor I32 for. the motor 24 when the latter is intended for use with alternating current.

In operation, the motor 24 revolves the crank member 40 to reciprocate the piston 51, drawing gaseous refrigerant into the crank case 34 through the suction valve I21 and forcing it out through the discharge shut-oil. valve I00 into the interior of the tubular member III. From the interior of the member II! the gas diffuses through the perforations H into the chamber II2, passing thence through the elbow union III and tube In, to the condenser H9 where it is liquefied bythe cooling eiiect of the air draft provided by the fan I20. From the bottom of the condenser N9 the liquefied refrigerant passes through the tube I2I into the receiver I23; thence outward through the tube I28, valve I25 to the line (not shown) leading to the cooling unit.

The purpose of the muflier or silencer H0 is to eliminate the audible pulsations of the gas passingto the condenser H9 and thereby p Omote quietness of operation, it having been found that with high speed compressor operation the vibratory discharge may be objectionably audible through the condenser or receiver in devices not provided with mui'liing means.

chamber II2.breaks up the impulses and promotes a smooth and quiet flow of gas to the condenser as well as even and continuous condensation and flow of liquid to the receiver.

As the compressor is driven at high speed, the splasher 61 splashes oil into the pocket 5| from which the oil runs down the hold 50 into the oil grooves 52 and 53. The helical advance of oil groove 53 is in such a direction that as the journal sleeve 38 rotates in the bushing L38 oil is carried along the groove 53 into the interior of the seal bellows 43, providing a supply of lubricant to the shoe l'l pressing against the re-'- vqlving collar 2. The oil carried into the interior of the bellows in the manner described accumulates in the latter until it rises to the level of the groove 54 in the outside of the bushing 38.- Thereafter, additional 011 entering the bellows causes a flow back through the groove 54 to the interior of the crank case 34. In its exit from the groove 54, the oil provides lubricant for the thrust of the crank member 40 against the end of the bushing 38. As oil is supplied to the inside of the bellows, rotation of the sleeve 36 and collar 42 tends to throw oil centrifugally into the sealing joint, thus assuring proper lubrication thereof.

It will be then seen that the foregoing provides a continuous supply of lubricant both through the seal cavity and to the thrust bearing and assures the maintenance of a supply of lubricant in the interior or the seal during the periods when the device is not running, since the only free exit for oil from the interior of the bellows is through The diiiusion of the gas through the perforations I I5 into the enlarged device. The strength oiLthe spring =I8' is suiflcient to excite. pressure slightly greater than the product. of the unit atmospheric pressure multiplied by the circular area inside the contact face of the shoe M on the collar 42.

By the provision of the strength of spring, it is assured that the thrust of the shaft is maintained toward the leit, preventing the development of end play and keeping the crank member uniformly in contact at all times with its thrust bearing provided by the end of bushing 38. Due to the use of the balanced seal arrangement previously described, it is possible to make the spring 48 of much lighter compressive strength than would be necessary if the latter had to overcome the tendency of the bellows to collapse in case the machine were to operate under partial vacuum. It is obvious that the use of this comparatively light spring keeps wear on the seal and thrust bearing to a minimum, resulting in long life of the parts and effective sealing.

The guiding of the ring 46 by the cylindrical extension 49 of the nut 45 keeps the shoe 41 accurately in alignment with the collar 42 and pre vents uneven wearing of the shoe face and subsequent leakage such as occurs due to wobbling of the seal shoe in devices wherein no such guiding means is provided.

The use of the journal sleeve 36 around the shaft extension 31 allows the entire rotative seal and journal assembly to be clamped tightly on the shaft by the crank member 40, the direction .of rotation of the shaft being such as to tend to maintain the crank member tightly screwed on its threads. The rotative parts of the motor and compressor thus form a rigid unitary assembly supported in accurately aligned bearings, while the parts are obviously cheap and easy to manufacture and assemble.

The resilient rings 88 and 90 supporting the outside ends of the motor compressor assembly provide cushioning means between the operating parts and the base 20, and due to the fact that this cushion mounting is concentric with the shaft its action in eliminating vibration is distributed throughout the complete 360 degrees of resilient rings. This arrangement is effective in preventing the transmission of motor and torque reaction vibrations to the base and eliminates any loss of the effectiveness of the cush ioning such as occurs in structures employing cushion mountings wherein the load is unevenly concentrated on the comparatively small areas of other types of resilient supports.

The above cushion mounting, together with the additional provision of the springs 2i supporting the entire unit, thoroughly precludes the possibility of vibration being transmitted to any cabinet or other structure on which. the condenser unit may be mounted in installation.

In the alternative shaft structure shown in Figure 13, the sleeve 36 shown in Figures 1 and 3 is omitted, the shaft I39 having an enlarged portion I40 forming the journal which operates in the bushing 38 in the manner previously set forth. The shaft I39 is hardened and has a shoulder I4I against which the sealing shoe 41 presses directly, eliminating the collar 42' and washer 42a shown in Figure 1. The shoulder I is grooved or undercut at I42 to allow the flat face thereof to be accurately ground. The crank member 40 is screwed on the threaded end I 43 of the shaft I39 so as to tightly engage a second shoulder I44 which is undercut at I45 to ensure flat finishing in manufacture. The operation of the device with the alternative shaft structure shown in Figure 13 is the same as that already described, the alternative structure however a1- lowing the omission of the sleeve 36, collar 42 and gasket 42a from the assembly as noted above.

In the arrangement of the device shown in Figure 11, the unitary condenser block 3| is attached to the motor shell 24 with the cylinder 35 inclined to provide a unit of minimum height, the use of the concentric cushioning ring 88 allowing this arrangement to be made without alteration in the supporting bracket structure.

In this structure the base I33 is shaped as an upwardly facing channel to the sides ofwhich are attached brackets I34 for the springs 2|, thus lowering the entire compressor mounting and further minimizing the height of the unit, the condenser I35 being made lower for the same purpose.

To facilitate attachment of the suction line from the cooling unit, the suction shut-off valve I21 may advantageously be attached at the right side of the crank-case 34 instead ofto the left side as shown in Figure 2.

It will be evident from the foregoing description that the high side or condensing unit structure forms a compact and simple combination, having few and simple working parts assembled with a minimum of bolts and other attaching means, and adapted to quiet operation in conjunction with any suitable type of cooling unit.

While the invention has been described impreferred form, it is not limited to the precise structures illustrated, as various modifications may be made .without departing from the scope of the appended claims.

. What I claim is:

1. In a refrigerating device including a compressor having a discharge opening for compressed fluid and a condenser, silencing means comprising, in combination, an outer shell enclosing a chamber, a perforated tubular member extending into said chamber, means establishing a passage for said fluid from said discharge opening into the interior of said tubular member, and means connecting said chamber to said condenser.

2. In a mechanical refrigerating system, a high side and a low side forming a closed circuit, said high side including a compressor having a. rotary shaft adapted to circulate a fluid through said circuit, means to actuate said compressor, annular resilientmeans disposed concentrically with said shaft and adapted to torsionally absorb vibrations of said compressor and actuating means, and a muffler in said circuit adapted to silence the circulation of said fluid.

LINDSAY H. BROWNE.

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