US1724553A

US1724553A - Fluid compressor

Info

Publication number: US1724553A
Application number: US4345A
Authority: US
Inventors: Frank M Bennett
Original assignee: Individual
Current assignee: Individual
Priority date: 1925-01-23
Filing date: 1925-01-23
Publication date: 1929-08-13
Anticipated expiration: 1946-08-13

Description

Aug. 13, 1929. F. M. BENNETT 1,724,553

FLUID COMPRESSOR Filed Jan. 23, 1925 4 Sheets-Sheet l 3mm Lbgl [Ma /med! attozwugdl Filed Jan. 23. 1925 4 Sheets-Sheet 3 .1 Guam M34 Aug. 13, 1929. BENNETT 1,724,553

FLUID COMPRESSOR Filed Jan. 23. 1925 4 Sheets-Sheet 4 Ill-1 30 past the piston rings.

50 nected to aneccentric upon Patented Aug. 13, 1929.

UNITED STATES FBANK BENNETT, orcAn'ron, onto- FLUID oomrnnsson.

application filed January This invention relatesto compressors such as are used for compressing ammonia gas and the like, and the objects of the improvement are to provide a compressor of either single or double stage type, in'which the usual connecting rod between the piston and crankshaft is eliminated, and in which the working parts are surrounded by lubricating fluid which absorbs the heat of compression; the lubricating oil being cooled by air, water orother cooling means. I

'The above and other objects may be attained by locating the cylinder and piston and other working parts within a water or air. cooled casing filled with lubricating oil surrounding the working parts. 3 The connecting rod may be eliminated by mounting either the piston or cylinder to oscillate or rock upon trunnions within the casing, the other member being directly conjnectedto the driving shaft as by an eccentric or the like, the fluid being taken into the cylinder and discharged therefrom through the trunnions which are provided with packing to prevent leakage ofthe gas; means being provided forequalizing the pressure to prevent leakage of atmospheric air into the casing or toprevent pressure in the casing from equalizing with the-discharge pressure An embodiment of the inventionis illustrated in the accompanying drawings, which- Figure 1 is a vertical, through a double stage compressor constructed in accordance with the invention, showing the condenser connected therewith; Fig. 2, a section on the line 2%2,Fig. 1'; Fig. 3, an enlarged, longitudinal sectional view of the'cylinder and piston; and l,

Fig. .4, a. longitudinal sectional 'view through a single stage compressor, [constructed in accordance with the invention.v

Similar numerals refer to similar parts throughout the drawings. 7

'Referring first to Figs. 1 to 3 inclusive, a two stage compressor is illustrated, in'which the cylinder is mounted to oscillate upon its trun nions, the piston being. directly lconthe, driving shaft by means of which the piston is reciprocated and the cylinder oscillated; the oil casing being arrangedto be water cooled in this form of compressor. I 1 I The compressor casing l may be cast insectional View 23,1925. seal m, 4, 345.

'tegrally with the'condenser'casing 2, the

usual coils 3 of which may be surrounded by a sheet metal casingLor' jacket 4, water being admitted at the upper endof the condenser casing as, at 5, and allowed to pass around the coils, between the jacket 4 and the re ceiver drum 6, an outlet 7 being provided'in the upper portion of the casing, between the acket 4 and the compressor casing 1,"whereby all ofthe water after passing downward around the coils, passes upward in contact with the compressor casing before'reaching the outlet, thus tending to cool the compressor casing for a purpose hereinafter stated. The drive shaft may be in the form shown at 8, or, if'desired, may be the usual crank shaft. An eccentric 9 is fixed upon the shaft and'is surrounded by an eccentric strap 10 directly connected to the end of the piston 11, which is mounted for reciprocation within the cylinder 12.

The cylinder is arranged to oscillate uponthe'fhollow trunnions'l3 mounted in the bearingsvl l and the intake and discharge connections 'are'made through the

pipes

15 and 16 respectively which are extended through the t'runnions. H y

Leakage of the'lubricating oil indicated at A, into the intake; connection, .as well as leakage of the compressed or high pressure gas into the oil, is prevented by packing 1 17 7 surrounding the inner ends of the intake and discharge pipes, within the hollow trunnions, aunitorm pressure being placed upon the packingas by the springs 19. Y For the, purpose of preventing cating oil fromfbeing drawn into the cylinder,'-and disch'argedout of thecompressor, it is desirable to equalize the pressure within the casing I with the pressure of the incom the lubriing gas. This may be accomplished as shownin Fig. 2, byproviding a" pipe 20 forminga connectionbetween the upper portion of the compressor casing '1 and the inlet pipe 15.

izing the pressureto prevent atmospheric air from .being drawn into the compressor, by providing a breather pipe 21 "connected to the chamber 22 of the piston', which receives gas at the intermediate pressure between the twostages of compression, said pipe'extending into the upper portion of the compressor casing for equalizing thepressure therein with theiintermediate' pressure of the gas.

' 1 In F- s, ilan'd 3 is shown a means of equaL The inlet pipe 15 communicates with the eceiving chamber 22' in the cylinder head '23. The gas passes out of the lower end of this chamber,through the annular slots 24, which are normally closed by means of a split ring valve '25 seated in an annular groove 26 formed in the cylinder head.

The passage of the gas is then downward into the upper end of the cylinder and then through pocket 27 in the upper end of the piston, said pocket having the annular slots 28 in its lower end, normally closed by the split ring valve 29, located in the annular groove 30 Formed in the piston communieating with the lower chamber 31 in the piston.

From this point, the gas passes downward into the piston, within the tube 32 and through the opening 33 in the lower end of said tube into the chamber 22, which may communicate with the breather pipe 21, above described, as through the passage 34.

The greater portion of the gas, however, will be permitted to pass upward around the outside of the tube 32 to the upper end of the piston chamber 35, which communicates with the slots 36 normally closed by the split ring valve 37, which is mounted in an annular groove 38 in the piston. Four radial lugs 39 retain the valve and piston ring, the remainder of the material being cut away as shown at 39, providing communicationwith the compression chamber 40, formed between theshoulders 41 and 42 of the piston and cylinder respectively, by reducing the diameter of the lower portion of the piston as shown at 43. The usual piston rings 44 are provided around the up per enlarged portion 45 of the piston.

, The lower end of the compression chamber 40 is provided with the conical reduced portion 45 communicating with the slots 46 which are normally closed by the discharge valve, preferably in the form of a split ring 47, which controls the passageof the compressed gas from the compression chamber 40 through the slots 46 and. 48 into the discharge chamber 49, which may be an annular chamber formed in the cylinder and communicating with the discharge passage 50, the upper end of which communicates with the outlet or discharge pipe 16.

The usual piston rings 51 are located around the lower reduced portion of the piston, and it will thus be seen that since the pressure within the casing 1 is equalized with the incoming gas, by the connection 20' between the casing and the inlet pipe, the lubricating oil cannot be, drawn past the piston rings 51 into the cylinder and discharged out of the compressor, as there is at all times of the cycle of compression operation, a higher pressure in the lower portion of the cylinder than in the casing 1.

In the operation of the compressor, the compression of gas is as follows; the gas enters the chamber 22 through the inlet pipe 15 and as the piston moves downward, or toward the shaft 8, the gas is drawn through the inlet valve 25.

As the piston returns, the gas just drawn in, passes through the split ring valve 29 the discharge port and thence out through the discharge pipe 16. v v

This construction forms of the extended piston a receiver which is continuously cooled by the lubricating oil surrounding the same, and thus cooling between the two stages of compression is effected, resulting in lower power consumption.

The lubricating oil within the casing 1 is, in turn, cooled by the water from the condenser or by, the usual form of water jacketing surrounding the casing, or water tubes passing through or around the same, or may be. cooled by air as shown in Fig. 4.

.In this type of compressor, it i very important that the heat of compression which is absorbed by the oil, be transmitted to the other cooling element such aswate-r or air, to the greatest possible extent, as discharged gas temperatures of 300 F. to 350 F. are customary and it is necessary that the oil be kept below the flash point to prevent disastrous explosion of the oil vapor and the compressed gas.

Suitable oil level gau es may be provided to indicate whether sufiicient oil is carried in the casing, but these gauges form no part of the present invention and for thi reason are not shown on the drawings.

, In Fig. 4 the inventionis illustrated as applied to a single stage compressor in which the piston 11 is mounted to oscillate upon hollow trunnions 13 through which the gas is taken inand discharged, the cylinder 12' being directly connected to the eccentric 9', upon the driving shaft 8', by the eccentric strap 10, and arranged to be reciprocated, the oil casing 1 being provided with air-cooling fins 55. v 1' The intake pipe 15' may be connected with the interior of the casing by the pipe 20 in the manner illustrated at 20 in Fig.2. This equalize the pressure within the casing with the pressure of the incoming gas, and in order to prevent lubricating oil frombeing drawn into the cylinder and discharged out of the compressor, the compressed gasat discharge pressureis admitted to the radial passages 56 andinto the annular groove 57 formed in the piston between the upper and lowers sets of piston rings 58 and 59 respectively. i

Thus intake pressure is provided within the oil casing, while discharge pressure is placed between the twosets of rings upon the piston, thereby preventing the lubricating oil from'being drawn into the cylinder from the oil casing.

From the above, it will be evident that a compressor is provided which may be of either single or double stage type, in which the, cylinder and piston are mounted for a combinedoscillatory, reciprocatory motion without the use of a connecting rod, the working parts being arranged to be operated Within a casing containing lubrieatingv oil, the oil absorbing'the heat of compression which is radiated through the walls ofthe casing as by air or water cooling or the like; means being provided forequalizing pressure within thecasing to prevent atmospheric air from being drawn into the casing and also to prevent lubricating oil from being drawn into the cylinder.

In Fig. 4 of the drawings the inlet pipe 15 communicates with the chamber in the trunnions 13. The gas passes out of the chamber 70 through the pipe 71 to the chamber 72 in the head of the piston 11. The gas then passes to the compression chamber 73 in the cylinder head through the annular slots 74, which are normally closed by means of the split ring valve 7 5 seated in an annular groove formed in the piston head.

Upon compression the gas passes from the compression chamber through the annular slots 76, which are normally closed by means of the split ring valve 77 seated in an annular groove formed in the cylinder head, and thence through the hollow portion 78 of the piston which communicates as at 7 9 with the discharge connection 16 mounted in the left hand trunnion 13.

I claim I v 1. A compressor including a casing adapted to contain lubricating oil, a driving shaft journaled in the casing, a cooperating piston and cylinder mounted in the casing, one of said cooperating members being provided with trunnions journaled in the casing and the other cooperating member directly connected to the driving shaft, means for placing exhaust pressure between the rings of the piston for preventing oil from being drawn into the cylinder and means for absorbing the heat from the oil in the casing. 2. A compressor including a casing adapted to contain lubricating oil, a driving shaft journaled in the casing, a cooperating piston and cylinder mounted in the casing, one of said cooperating members being provided 'withtrunnions journaled in the casto the driving shaft, means for placing exhaust pressure between the rings of the pistonforpreventing oil from being drawn into the cylinder and means for absorbing the heat from the oil in the casing.

3. A compressor including 'a casing adapted to contain lubricating oil, a driving shaft journaled in the casing .and provided with anieccentric, a cylinder. providedwith hollow trunnions journaled in the casing, gas inlet and discharge passages being connected to said hollow trunnions, a. piston within the cylinder provided with an cecentric band mounted upon said eccentric, and means for placing exhaust pressure between the rings of the piston for preventing oil from being drawn into the-cylinder.

4. A compressor including 'a casing adapted to contain lubricating oil, a driving shaft journaled in the casing and provided with an eccentric,- a cylinder provided with hollow trunnions journaled in the casing, gas

inlet and discharge passages being connected to said hollow trunnions, a piston within the cylinder provided with an eccentric band mounted upon said eccentric, and means for absorbing the heat from the oil in the casing, and means for placing in-take gas pressure in the casing and discharge gas pressure between the rings of the piston for preventing oil from being drawn into the cylinder.

5. A compressor including a casing adapted to contain lubricating oil, a driving shaft journaled in the casing and provided with an eccentric a cylinder provided with hollow trunnions journaled in the casing, gas inlet and discharge passages being connected to said hollow trunnions, a piston within the cylinder provided with an eccentric band mounted upon said eccentric, means for absorbing the heat from the oil in the casing, and means for placing exhaust pressure between the rings of the piston for preventing oil from being drawn into the cylinder.

6. A two stage compressor including a cylinder, a piston mounted within the cylinder, gas inlet and discharge passages connected to opposite end portions of the cylinder, means whereby one stage of compression is produced upon the up stroke of the piston and a second stage of compression upon the down stroke thereof, the piston being hollow and providing a receiver, for the gas between stages of compression, and means communieating with the receiver for preventing atmospheric air from being drawn into the compressor.

7. A two stage compressor including a cylinder, a piston mounted within the cylinder, gas inlet and discharge passages connected to opposite end portions of the cylinder, means whereby one stage of compression is produced upon the up stroke of the piston and a second stage of compression upon the down stroke thereof, the piston being hollow and providing a receiver for the gas between stages of compression, and means within the piston for causing the gas to travel the full length of the piston to allow the maximum; cooling of gas in the piston.

8. A compressor including a cylinder, a hollow piston mounted in the cylinder and forming a receiver chamber, a first stage compression chamber at one end portion of the cylinder, a second stage compression chamber at the other end portion of the cylinder, means for conveying gas through the piston from the first stage compression chamber to the receiver'chamber of the piston and thence to the second stage compression chamber, a non-return discharge valve in the piston for preventing the gas from passing back from the receiver chamber to the first stage compression chamber and a non-return suction valve for preventing the gas from passing back from the second stage compression chamber to the receiver chamber.

of the piston for preventing oil from being drawn into the cylinder.

10. A compressor including a casmg adapted to contain lubricating oil, a driving shaft journaled in the casing, a cooperating piston and cylinder mounted in the casing, one of said cooperating members being provided with trunnions journaled in the casing and the other cooperating'member directly connected to the driving shaft and means for placing intake pressure in the casing and discharge pressure between the rings of the piston for preventing oil from being drawn into the cylinder.

In testimony that I claim the above, I have hereunto subscribed my name.

FRANK M. BENNETT.