US2031080A - Motor pump and condensing unit - Google Patents

Description

INVENTOR.

5 Sheets-Sheet l H. R. VAN DEVENTER MOTOR PUMP AND CONDENSING UNIT Original Filed Sept. 15, 1929 Feb. 18, 1936.

Feb. 18, 1936. H. R. VAN DEVENTER MOTOR PUMP AND CONDENSING UNIT Original Filed Sept. 13, 1929 5 Sheets-Sheet 2 IM "EN TOR. HARRY R. VwDa/E/vrm,

Feb. 18, 1930. H R, V DEVENTER 2,031,080

MOTOR PUMP AND CONDENSING UNIT Original Filed Sept. 15, 1929 5 Sheets-Sheet 5 #422) E UswDevEA/me Feb. 18, 1936. H. VAN TER 2,031,080

MOTOR PUMP AND CONDENSING UNIT Original Filed Sept. 13, 1929 5 Sheets-Sheet '4 I N V EN TOR. A i/EB! P. 149 DEVENIEB Feb. 18, 1936. H. R. VAN DEVENTER 2,031,080

MOTOR PUMP. AND CONDENSIILIG mm Original Filed Sept. 15, 1929 5 Sheets-Sheet 5 JX WMWIA Patented Feb. 18, 1936 MOTOR, rpm AND CONDENSING UNIT Harry It. Van Deventer, New York, N. Y.. assignor,

by mesne assignments, to General Motors Corporation, a corporation of Delaware Application'september 13, 1929, Serial No. 392,301 Renewed October 6, 1933 11 Claims. (01. 62-115) This invention relates to a motor-pump and condensing unit which may be used for a variety of purposes, but which for the sake of illustration is herein described as applied to a refrigeration machine.

The objects of the invention are to provide a machine of simple construction wherein the working parts are sealed within a gas tight chamher into which the outer air cannot enter, a portion of which may form a suitable condenser. As the motor shaft does not project intothe outer air, the machine has no stufiing box or seal and is free from the troubles caused by the wear of such devices.

Another object is to provide an improved means of lubricating the pump and motor and of separating the lubricant from the refrigerant or other material being pumped, the separation being accomplished by physical laws unvarying in operation and unafiected by time or wear.

A further object is to provide a simple and cheap assembly of the various parts to particularly adapt this unit for use in household refrigerators-and the like and to adapt the unit to cheap mass production.

In the accompanying drawings, Fig. 1 is a vertical longitudinal sectional view through a machine unit embodying the invention.

Fig. 2 is a view of the external motor end of Fig. l and Fig. 3 shows a portion of the pump.

Figs. 4, 5 and 6 are modifications of the interio arrangement of the machine.

-The figures illustrate a unit suitable for use in a small refrigerating machine such as com- .monly used in residences. Such machines usually employ a pump or compressor, a motor for driving the same and a condenser wherein the compressed refrigerant gas is liquefied by the application of cooling air or water to the exterior of the condenser. These elements, to wit, the pump, motor, and an air cooled condenser and means for cooling the condenser are, by the invention, combined into a compact unit adapted to be easily moved and connected to the usual evaporator or cooling coil and expansion valve, which are not shown herein, as these may be of 7 any suitable form and many forms are well known and the method of connecting them to such a unit as herein described is also well known.

The numeral i denotes a main plate or support for the 'motor and pump carrying in any suitable manner as by the frame 2 secured thereto, the motor stator t mounted in operative relation to the motor rotor t, which is supported on shaft 5. This shaft is supported in bearing 6 in the plate I. These motor parts are enclosed by the casing l secured to the main plate l. in any suitable manner so that the space about the motor is gas-tight and air cannot find ingress.

Mounted upon plate l in any suitable manner is the pump 8, the rotor or other moving element of which is operated by shaft 5. This pump may be of any suitable type either of the so-called rotary or reciprocating type, and has the usual suction or intake 9 (which is brought to an opening in plate I) and a discharge Ill, which empties into pan Ill. The pan is positioned below the pump and forms a lubricant receptacle into which the pump discharges. This pan is closed by the cover l2 and has an outlet pipe l3 communicating therewith, said pipe having its lower end M above the normal lubricant level in H, and its upper end l5 adapted to discharge compressed gas in the upper portion of the condenser shell l6, preferably near the plug opening ll so arranged that the lubricant may be initially inserted through H and i5 to provide the body of lubricant it.

The condenser shell it is secured to plate 9 in any suitable manner so that the interior of same is gas-tight, and may be provided with a plurality of fins i9, 20 for radiating heat therefrom.

A suitable motor driven fan 2i may be mounted upon. bracket 22 secured to the condenser it.

An outer casing 23 y surround the condenser it, and the fan 2i so arranged so as to draw the air inat 2t, pass it over the outer surface of i6 and the fins and eject it at the opening 65 in front of the fan. Or, the air-flow may be reversed if desired.

The complete unit is supported on feet 25, 26, 2! which may be tipped with rubber to lessen vibration.

Theelectric motor is provided with suitable gas-tight terminals 2t, 29 mounted upon plate i or upon the casing 74, and it will be understood that all the working parts are totally enclosed, there being suitable pipe connections into the unit whereby it may be properly piped to other apparatus, and that the outer air cannot find in- .trictional heat of the pump withwhich it is in conductive contact, will cause the compressed gas and any lubricant mixed therewith to separate by distillation, the more volatile gas passing up the pipe I3 to the condenser I6, and the less volatile lubricant remaining behind in the bottom of pan II at I8 as a liquid.

From I8 the lubricant is forced by the gas pressure which exists above it into pipe 30 via duct 3i to the bearing 6, thereby lubricating motor bearing. The moving parts in the compressor 8 (shown in Fig. 3) are lubricated in the following manner: some of the lubricant passing up the pipe 30 passes along the end plate I in a groove 61 which is in contact with the rotor 68, at a point where a blade 66 is near and moving away from the bottom of a slot 65, and for a number of degrees in the direction of rotation thus taking advantage of the pumping action of the backs of the blades 86 in the slots 65. When the blades pass around to a point where the blades are going back toward the bottom of the slots, the lubricant is forced to all moving parts of the compressor. Or, it may be accomplished in any convenient manner other than that shown.

The compressed gas discharged at I comes in contact with the relatively cool wall of the condenser IE which is cooled by the current of air drawn over the outside of the condenser by the fan H or by direct radiation without the fan. The gas li uefies and collects at the bottom of the condenser at 32 and is forced via the pipe connection 33 to the usual expansion valve shown diagrammatically at 34. Here the gas expands and enters a suitable expansion coil 35 usually located within a refrigerator where refrigeration takes place. The expanded gases return via pipe 36 to the suction or intake 9 of the pump and thiscycle is repeated as long as the machine is in operation.

The period of operation of the machine is usually controlled by a thermostat (not shown) controlled by the temperature of the expansion coil or chamber 35. Both the pump and fan motors may be controlled by this thermostat and as such controls are well known, they are not herein described in detail.

Should any of the lubricant applied to. bearing 6 leak out into the motor casing I, it will run down to the bottom thereofand find its way through opening 37 to the body of refrigerant and circulatingtherewith ultimately return to the main body of lubricant at I8.

Only a very small portion of lubricant will circulate in this manner. No more than occurs with other types of machines in common use, and this small quantity has no appreciable efiect upon either the lubricating or refrigerating cycle.

The pressure equalizing opening 38 is provided to insure the pressure inside I being the same as in the condenser and at no time is the interior of I under vacuum. By this arrangement the pump unit is kept cool on the motor end, as the motor casing projects freely into the atmosphere and heat can readily radiate therefrom and not be confined within the motor chamber as in other types. Also the pump is confined within the condenser and cooled by the gases discharged therein which are in turn cooled by the condenser, the arrangement of pump and condenser being very compact as one is within the other.

- In Fig. 4 is shown a modification of the construction just described wherein the casing 39 surrounds the pump and forms a receptacle for the lubricant, thus forming a. closed casing within the condenser I6.

Within casing 39 are the baffle plates 40, 4| around which the gases must pass to find egress at 42 to the condenser. 42 also serves as the lubricant filler hole.

In this construction the heat of the pump is most efiiciently used to distill off the lubricant and the mechanical construction simplified as compared with that shown in Fig. 1.

Fig. 5 shows a modification wherein the pump shaft is extended into the condenser as shown at 43 and a fan 44 mountedthereon which when the pump is in operation throws the gas within the condenser against the inner walls thereof, thereby facilitating condensation. As a further aid, the discharge from the pump may be connected to a perforated pipe 45 coiled about the fan and the gas sprayed therefrom into the path of the fan blades and thereby brought rapidly in contact with the cool wall of the condenser.

Fig. 6 shows another modification wherein shaft 43 extends to bearing 14 and supports and rotates a perforated hollow member 45a which is connected to the outlet from the pump and which as it revolves, sprays the gas against the wall of the condenser, the fan blades being eliminated.

The details of construction of this motor-pump unit may be varied within wide limits without departing from the scope of the invention as defined by the appended claims. One arrangement contemplates making the plate I of cast iron machined on the pump side to provide the boss 46 which may form one end plate of the pump 8. The pump may consist of the first stage housing 41, the center plate 48, the second stage housing 49 and the end plate 5Ilall ground on their adjacent surfaces and held to plate I by means of bolts passing through them, one of which is shown at 5|. A passage or port 52 connects the first and second stage of the pump. The plate I has a boss 53 in which is made or supported the bearing 6 for the shaft 5. The rotor 4 is secured to this shaft and abuts against the shoulder 54 of the boss and is so adjusted as to prevent excessive end play. The rotor is secured to the shaft by any suitable means such as the key 55 and screw 55. r

The stator 3 is secured to the support 2 which in turn is secured to plate I by screws, one of which is shown at 55.

The suction pipe 3 from the pump is brought to a tapped hole 56 in plate I from which a pipe may be connected to other apparatus. The hole 33 in plate I is also tapped for a pipe connection, for leading liquid refrigerant to the expansion unit. The motor terminals 28, 29 are mounted gas-tight in the plate I and the casings I and I6 are secured to the plate I by means of bolts, one of which is shown at 51.

The heat radiating flanges outside casing I6 are secured thereto in any suitable manner such as by welding as shown at 58, or one piece of metal may be crimped around the casing I6, as shown at 59 and secured by welding at points 60, 6| to the casing I6 and also welded at 62, 63 to the outer casing 23. The legs 26, 21 may be cast integral with plate I or secured thereto in any suitable manner.

The bracket 22 may be cast with the leg 25 integral therewith or secured thereto and the fan motor is removably secured thereto by screws 64. The bracket 22 may be welded to casing I6 so that no gas leak will result at this point which might occur if it were held by screws passing through the wall of it.

The result of this construction is a simple and cheap unit assembly having no exposed parts and presenting a smooth exterior easily finished and kept clean. The number of joints which might leak are reduced to a minimum and these joints are easily machined and. made tight. 7

The casings T and it may be of cast metal but are preferably drawn steel pots which are less liable to leak than castings, and on which the flanges abutting against plate 6 are more readily made flat and accurate than where castings are used.

I claim:-

1. In a motor-pump unit, the combination of a motor and pump, a common support therefor comprising a plate, said plate having apertures in communication with the intake to and exhaust from said pump, a casing forming with said support a gas-tight chamber, means within said chamber for retaining a body of lubricant, means for supplying said lubricant to the motor and pump, and means in said chamber for retaining a body of liquid separate from said lubricant.

2. In a motor-pump unit, in combination a motor, a pump driven thereby. a sealed casing about said motor and pump a portion of which forms a condenser, and means actuated by said motor for agitating the contents of the condenser to cause said contents to contact upon the inner walls thereof.

3. A motor-pump unit as claimed in claim 2 wherein the agitating means includes a rotating member adapted to distribute the exhaust from the pump over the inner walls of the condenser.

4. In a refrigerating machine, a plate forming a motor support, a motor having a,horizontal shaft supported thereby, a casing about said motor secured to said plate and forming therewith a chamber enclosing the motor, a pump supported by said plate and adapted to be operated from said shaft, a casing about said pump having a portion below the pump adapted to hold a liquid refrigerant, said plate having an opening therethrough below said shaft communicating with the interior of the pump casing above the normal liquid level therein whereby any liquid in the motor casing will flow by gravity into the pump casing.

\ motor, a pump driven thereby, a sealed casing about said motor and pump a portion of which forms a condenser, and means actuated by said motor for agitating the contents of the condenser to cause said contents to contact upon the inner walls thereof, said last named means includinga hollow shaft having perforated members connected thereto, said shaft and members being in fluid communication with the pump so as to distribute the exhaust therefrom over the inner surface of the condenser.

7. A motor-pump unit as claimed in claim 6 wherein the agitating means includes a rotating member adapted to distribute the exhaust from the pump over the inner walls of the condenser, said shaft and members being in fluid communication with the pump so as to distribute the exhaust therefrom over the inner surface of the condenser.

8. A refrigerating apparatus comprising a refrigerant liquefying unit and an evaporating unit in a closed refrigerant circulating circuit and including a motor, a compressor for compressing said refrigerant, and a condenser having liquid refrigerant therein, said compressor having a shaft in direct drive relationship with said motor, said refrigerant liquefying unit including a sealed casing for said motor and compressor hermetically sealing said motor and compressor within said casing, said compressor discharging compressed refrigerant into said casing, and a fan within said casing in direct drive relationship with said motor for agitating gaseous refrigerant in said casing, said fan being above the level of the liquid refrigerant and lubricant in said condenser.

9. A refrigerating apparatus comprising a refrigerant liquefying unit and an evaporating unit in a closed refrigerant circulating circuit and including a motor, a compressor for compressing said refrigerant, and a condenser having liquid refrigerant therein, said compressor having a shaft in direct drive relationship with said motor, said refrigerant liquefying unit including a sealed casing for said motor and compressor hermetically sealing said motor and compressor within said casing, and a fan within said casing in direct drive relationship with said motor for agitating the gaseous refrigerant in said casing, said fan being above the level of the liquid refrigerant and lubricant in said condenser.

10. A refrigerating apparatus comprising a refrigerant liquefying unit and an evaporating unit in a closed refrigerant circulating circuit and including a motor, a compressor for compressing said refrigerant, and a condenser having liquid refrigerant therein, said refrigerant liquefying unit including a sealed casing for said motor and compressor hermetically sealing said motor and compressor within said casing, and a fan within said casing driven by said motor for agitating the gaseous refrigerant in said casing, said fan being above the level of the liquid refrigerant and lubricant in said condenser.

11. In refrigerating apparatus the combination of a compressor, means for actuating said compressor, a receptacle into which said compressor discharges, a condenser in communication with said receptacle, and mechanical means for producing flow of the compressed gaseous refrigerant from said receptacle into said condenser.

HARRY R. VAN DEVENTER.

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