US1689178A

US1689178A - Pump

Info

Publication number: US1689178A
Application number: US73106A
Authority: US
Inventors: George L Strebler
Original assignee: STREBLER APPLIANCES Inc
Current assignee: STREBLER APPLIANCES Inc
Priority date: 1925-12-04
Filing date: 1925-12-04
Publication date: 1928-10-23
Anticipated expiration: 1945-10-23

Description

Oct. 23, 1928.

G. L* STREBLER PUMP Filed Dec. 4, y1925 5 sheets-sheet 1 ihnen/Zar."

ar A )l f Oct. 23, 1928. 1,689,378

. G. L. STREBLER arm ey.

G. L. STREBLER PUMP l Filed Deo. 4, 1925 5' Sheets-Shes?. 3

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' G. L. STREBLER PUMP Filed Dec. 4, 1925 S'sheetsfsneet 4 r.| QSQM mm @w mw ,VY Q ww W@ w Km A v Oct. 23, 1928.

G. L. STREBLER Filed Dec. 4, 1925 5 sheets-sheet 5 Patented Get. 23, i928.

.UNITED STATES- l 1.589.178 Parent OFFICE.

GEORGE L. sTRnBLEB., 'or sfr. LOUIS, MIssounLnssIenon 'ro sTnnBIiEn APPLIANCES, INC., or sfr. LOUIS, MISSOURI, A CORPORATION OF DELAWARE.

BUMP.

Application filed December My invention relates to power driven pumps and has for its object to 'provide a pump which is a distinct and practical improvement to overcome certain practical objections to, and defects in, the present types of pumps which lhave the connecting rod pivotally mounted upon a wrist-pin within the piston and the Opposite end connected to a crank-shaft, orits equivalent. I

Another object of the invention is to provide a pump structure wherein the axis of' the driving members for imparting reciproeating movement to the pistons7 are disposed in parallel relation to the axis of the cylinders and pistons at all points of the revolution of the actuating means for said driving` members.

still further object of the invent-ion is to provide wrist-pins for the pistons which extend beyond the peripheral face thereof upon opposite sides thereof and extend through slotted openings in the walls of the cylinders and upon which extended wristpins are positioned slidable cross-heads, the longitudinal axis of which are disposed at a right angle to the axis of the wrist-pins and the axis of the cylinders and pistons, and upon which cross-heads are mounted facial slotted driving` heads of the driving members for alternate sliding movement upon said cross-hear for imparting reciprocating movement to the pistons through the medium of driven eocentrics.

A still further object of the invention is to unite each pair of cross-heads upon "either side of opposed cylinders and to mount them for reciprocating` movement upon slide-bars so that the pressure exerted by the driving members through the. medium of suitable actuating means bear on the slide-bars and is resisted thereby. i

A further obj ect of the invention is to provide a pump structure applicable to domestic and light commercial electric refrigerators wherein the peculiar structure thereof serves to provide an oil separator within the pump to prevent an excessive amount of lubricant from entering the cylinders for transmission into the high pressure pipe line with the compressed gases to be condensed, or. when used as an air compressor to eliminate oil from eontaminat-inglr the compressed air. e

A still further object of the invention is to provide a pump which possesses advantages in points of simplicity and eflieiency 4, 1925. serial No. 73,106.

and at the same time proves itself compara tively Ainexpensive in manufacture.

With th'eabove and other objects in view whichwill be apparent hereinafter, the invention consists inthe novel features `of con struct-ion, larrangement and combination of parts hereinafter more fully described and finally pointed out inthe claims hereto ai pended. Y e

Referring Vto lthe drawings forming a part of thisspecification wherein like characters of reference denote similar parts throughout t-he several views :r Fig. l, is aside elevation of a pump with the case in sectional elevation and embodyinnA the features of my invention. i i

Fig. 27 `is a longitudinal vertical sectional view ofthe' pump. s

Fig. 3, is ahoriZonta-l sectional view of the pump.

F Il, is a transverse vertical sectional.` view of the pump midway the ends thereof.

Fig. 5, is al transverse vertical sectional view of the pump through one of the pistons.

Fig. G, is an assembly rView of an automatic electric refrigerating apparatus unit/)ein bodying the pump. .f

Vifhile l have shown by reference to Fig. 6. the pump .as used vin connection with 'an electric refrigerating system7 .it is, of course7 understood that the pump itself is applicable to other uses7 such as an air compressor, water pump, vacuum pump, moto-r.7 steam lengine and the like.

In carrying out the aim of myp resent p ump construction, l employ a suitable hollow case body l of any suitable size and shape. The case body l isl provided with suitable supporting legs 2. or their equivalent, which can beseoured to a suitable base by means of suitable and well lino-wn fastening devices used for such purpose. The case body 1 is provided with suitable heads 3 and 4, either, or both of which may be removably fixed to the casel body l. For illustrativepurposes only., howevery' have shown the head Sas integral with the case body l, while the head l is shown as removably fixed tothe case bodyl by means of .suitable fastening devices, such as suitable screws 5. The head '3 of the casebodyl` is provided with asuitable low pressure inlet opening 6 and a suitable high pressure outlet opening 7. The opening 6 maybein the casing body l, if desired. The upper wall of the casing body 1 is provided upon its inner Y face with a pair of suitably space-d inverted recesses or chambers 8 and 9 to provide a pair of spaced opposed bafle walls 10 for cach recess. Each pair of walls 1() are provided with opposed laterally directed grooves 11, the purpose of which will be apparent hereinafter. The upper face of the casing body 1 is also provided with a suitable. electric motor supporting base 12.

The pump mechanism employed in accordance with my invention will now be described. As clearly shown in Figs. 1 to 5, inclusive, of the drawings, the pump mechanism is represented as comprising a suitable cylinder block 13 disposed, preferably'in a horizontal position Within the case 1 and held in such position in fixed relation to the case 1 in any suitable manner, but shown in the drawings asv held in osition by means of suitable screw threaded astening devices 14, which are receivable in suitable bosses 15. This arrangement provides a three point support for the cylinder block.

The cylinder block 13, shown in the drawings, is provided withduplex cylinder bores,

or cylindersdesignated 16 and 17 which are arranged in opposed relation and in axial alignment. The

cylinders

16 and 17 have open outer ends, and their inner ends are separated by means of a suitable partition head 18, which is provided with a transverse bearing bore 19 within which is mounted a suitably driven shaft 20. The shaft 20 is supported at opposite sides of the. cylinder block 13 by meansof

suitable bearings

21 and 22, which in turn are supported by the case heads 3 and 4. One end of the driven shaft 2() extends through lthe case head 4 and a suitable stuffing box 23 for connection with a suitable source ofpower.

A pair of

suitable pistons

24 and 25 are arranged to reciprocate within the cylinders 16`and 17, respectively. The pistons both move in the same direction, in unison, so that while one piston lis compressing a charge in its respective cylinder toward the inner end thereof during the inward stroke of the piston, the other cylinder is taking in a charge to be compressed during the inward stroke of its respective piston, as will be apparent hereinafter.

The

pistons

24 and 25 are of peculiar conA struction in that they are closed by means of ahead at both ends.v The inner ends of the

pistons

24 and 25 are provided with suitable

automatic intake valves

26 and 27, respectively to permit a charge to enter their respective cylinders through the inner heads of the pistons during the return, or outward stroke of each piston.

The

cylinders

16 and 17 are provided with

suitable intake ports

28 and 29, respectively. These

intake ports

28 and 29 are so positioned at their lower ends as to communicate with slot-ted port openings 30 and 31 in the walls of the

hollow pistons

24 and 25, respectively, at all times, regardless ofthe positions of the pistons, as clearly shown in Fig. 2. The

intake ports

28 and 29 .extend upwardly through upright `tubular extensions 32 and 33 which form a part of each

cylinder

16 and 17, respectively. The tubular intake port extensions 32 and 33 extend upwardly into the inverted case recesses or chambers 3 and 9, respectively, a suitable distance, and, are

each provided with a peripheral'flange, or

vbattle 34 which are receivable in laterally directed grooves 11 of the spaced baffle walls 10. By this arrangement, it is apparent that due to the fact that the case 1 is filled with oil to a predetermined level designated 35, that regardless of the splashing of the oil by working` parts of the pump mechanism, such forv instance as eccentries hereinafter described, the oil will be retarded and baftled and bythe aid of gravity will be prevented from entering the upper ends of the intake ports 29 and 30 and finding its way into the

hollow pistons

24 and 25 and thence into the compression chambers. f The walls of the cylinders and'pistons are well lubricated from the open ends of the cylinders, as is manifest. v f i Gas taken in through the

intake ports

23 and 29 from the pump chamber passes into the

hollow pistons

24 and 25 through, the slotted piston port openings 30 and y31, re.-Y spectively, and then it passes through the automatic intake valve seat openings 36and 37 of the

pistons

24 and 25, respectively into the compression chambers of their respective cylinders during the outward jor suction stroke of thepistons. The gas during the compression stroke of the

pistons

24 and 25 is forced out of the compression chambers of the

cylinders

16 and 17 through the outlet port openings 38 and 39, respectively in the partition head 18 of the cylinder block 13 and passes over the check valves 40 and 4l, rcspectively in the cylinder block port head 42 and into the

delivery ports

43 and 44, respectively, which ports communicate at 'their upper ends with a single outlet port 45 which latter port communicates with the outlet port 7 in the case head 3, as will be apparent from Figs. 2.and 4.

The means for imparting reciprocating movement to the pistons 24 and 25A through rotary movement of driven means, which is, in its preferred embodiment, the shaft 20, resides in providing the driven means upon opposite sides of the cylinder block 13 with a pair of suitable eccentrics `designated 46. The eccentrics 46 are each suitably fixed to the shaft 20 and are each further held against displacement by means of the nuts 47 which nuts have screw threaded engagement with the driven Vshaft 2O and engage the outer faces of the eccentries 4G, as shown in Figs. 3 and 4. Y'

rese

Mounted `upon `each eccentric 46 is a strap section 48 of a suitable piston driving meinber. The strap section 48 of each driving member is provided at one end with a driving head 49 and at the opposite end with a driving,r ahead 50. The strap section 48 of each piston driving member is preferably connected With the driving heads 49 and 50by means ofsuitable connections, such as arms l and 52, respectively. v'Ihepiston driving members are both arranged to the sides of the cylinder kblock 13, as clearly shown in Figs. l, 3 and 4, andthe axis, or center lines thereof are each at all times maintained in a vposition parallel vto the axis of the cylinders at all points ot the revolution of the eccentrics 4l and merely raising and Ilowering with relation thereto with the movement ofthe eccenv trics. l

rl`he driving-heads 4910i the driving members are each vprovided .With a suitable facial groove 5,3upon its inner tace, which grooves l53am disposed `at a right angle to the axis ot thedrivi-ng members and to the axis of the cylinder 16. Receivable inthe facial groove ot eachpiston driving-heael 49 is a suitable vertically disposed cross-head 54 upon which the grooved driving heads 49 slide, or reciprocate in a vertically disposed pat-h, or in other Words at a right angle to the stroke-of the pist0n 24.

The cross-heads 54 are mounted .to reciprocate upon ,a pair ot spaced slide bars 55 which l,are arranged upon each side ot the cylinder bloc-k 13 so thatthe .motion of the crossheads 54 are coinc-.i.clent.\vitli, or parallel to the axis, or center line of the cylinder 16. In order to transmit reciprocating motion to the piston 24, I provide the piston 24 near its outer end with a Afloating Wrist-pin 55. The wrist-pin 55 extends beyond opposite sides ot the piston 24 and extends through opposed longitudinally disposed slotted openings 56 in the wall ot cylinder 16 and finally seated at its ends in openings 5T disposed centrally of the cross-heads 54. By this arrangement, both cross-heads 54 must move in a path parallel to Vthe faces ot the slide bars 55 on which the cross-heads 54 slide back and fort-h. In this Way, Ythe pressure exerted by the `driving members through the eccentric bears on the slide bars and is resisted by them.

The opposite piston driving heads 5() ot the fthe cylinders and `to the stroke of the pistons, as 1s manifest.

The cross-.heads59 are also mountedto reciprocate horizontally upon the sameslide bars 55 that-the cross-heads 54 slide upon as the slide ybars extend tromend to end ot the cylinder Vblock 13, so that the motion of the cross-,heads 59 will also `be coincidentwvitlnor parallei to the axis of the cylinders 1G and 17. ln order to transmit ymotion through the driving members to piston 25, I provide piston 25 near its outer end With `a -iioating Wrist pin 6() parts, botheross-heads 59 must move,"asldo 1 t-hecross-he'acls 54 Which are in a path paraflilel to the faces ot the slide ibars '55 upon 'which all the cross :heads slide and -to Ithe axis ot the cylinders 16 andlfr'. Inthis Way, the -pressure exerted iby the driving :mem-bers through both eccentrics bears on fthe slide bars 55 and is resisted by them. j i r A f I Y Tilting movement ofthe cross-:heads 54 and 59 ismade impossible by connecting each pair 0i cross-:heads 54 and 59 by means ot af pair ot connecting bars 613 which .also slide yuponlth'e slide bars 5,5. i

1t Will'be apparent from the foregoing description, that at all times'during rotary motion of the eccentrics 46, circular motion is imparted to the three points ot connection .ot the driving members `withthe cross heads and eccentric which causes a straight reciproca-t ing motion of the cross-heads at both ends ot the cylinder block. The axis ot the driving members are at all times parallel with the axis of the'cylindeiits and pistons although they move above and below kthe axis oli the ,cylinders and pistons during rotary movement ot the eccentrics.v Consequently, at all points of each revolution of the eccentrics 46', the driving members at their sliding connection with both pairs of cross heads have a tendency'to either pull, or push the cross heads excepting at thetwo dead points due to the fact that the grooved driving heads are either pnshi-ng,'or pulling at a tangent during their alternating sliding movement upon the .cross heads at a right angle to the axis and stroke ot the pis-.`

tons. That is to say the driving members pull the pistons in their compression stroke and push the pistons in the outward, or intake stroke. 'The tangent vpull and push is set up bythe circular motion imparted to the drive heads by the eccentrics revolving Within the strap sections of the driving members.

It will be recalled that the oil Within the pump case provides a splash system ot' lubrication tor the Workin g parts ot the pumpv and that theintake ports to the hollow pistons and the compression .chambers'ot the cylinders are sul llil() so guarded and baiiied due to the case walls l0, the upright tubes 3l and 32 and the baille Y plates 34 thereof being disposed in laterally domesticor light commercial electric refrigerators, and when. the pump is used as an air compressor, only the compressed air is free from oil contamination and yet thepump parts are thoroughly lubricated, as is evident.

A refrigerating system for domestic or commercial use employing' the hereindescribed pump will now be described The pump when used in connection with a domestic or a commercial refrigerator is mounted upon and fixed to a suitable base 64 and is actuated by means of asuitable electric motor 65 positioned upon and fixed to the motor base 12 upon the top of the pump case 1. VThe pump is driven through the medium of a belt 66 riding over. a pulley 67 fixed to the armature shaft 68 of the motor and a pulley 69 fixed to the driven shaft 20 of the pump. The pulley 69 is provided with a pluralit of radially directed fan blades 70 which c irect a current of air over the pump case 1 thereby eliminating undue heating of the pump. The armature shaft 68 of the motor 65 is also provided with a plurality of suitable suction fan blades 71 positioned beyond the pulley 67 Y ered by means of a Wire mesh closure 7 3 and is provided at its lower end with a plurality 0f cool air openings 74. The Wall of the conduit adjacent the fan 71 is provided with an air outlet opening 75 in which the suction fan 71 is disposed. Positioned Within the air conduit 72 are suitable` condensing coils 76 which are connected at their upper ends with a. high pressure delivery pipe 77 by means of a suitable coupling 78. The pipe 77 leads from the discharge .side of the pump so that gases compressed in the pump can be conveyed to the coils 76 to be condensed therein.

The condensed gases or liquid flows froml the condensing coils 76 into a suitable liquid receiver 79 through a drain pipe 8O connected with the lower ends of the condensing coils.

The discharge end of the liquid receiver is connected with anevaporator head or casncsaivs ingl 81 by means of a supply pipe 82 which communicates with a valve passage 83 which passage is normally closed by means of a` needle valve stem 84 which is actuated by means of a suitable float 85 fixed to the outer end of a lever arm 86 which lever arm is pivotally connected, as at 87, to a bracket 88 within the evaporator head 8l. The' evaporator head 81 is provided with a plurality of suitable freezing pipes 89 which communicate with the interior evaporating chamber 90 thereof which are filled with a liquid refrigerating agent 91, such .as methol chloride, sulphur dioxide, or their equivalent, the level of which is retained a predetermined level in the evaporator head 81.

Extending into the evaporator above the liquid level therein is a low pressure pipe 92 which is directed from the evaporator head i 81 and connected at its opposite end with the pump case 1 so as to communicate with the interior thereof which interior acts as a sup# ply receiver for the gas discharged from the evaporator and from which they are drawn into the compression chambers of the pump cylinders to be compressed and delivered to the condensing coils for condensation thereof for return to the liquid receiver and evaporator as needed, which is determined by the action of the float 85.

The starting and stopping of the electric motor 65 isshoivn as controlled by' means of what is commercially known as a mercvoid designated 93 which is electrically connected with motor electrical conductors 94 and 95 by means of the

conductors

96 and 97, respectively, which are in turn vconnected with suitable electrical supply conductors 98 and 99, respectively controlled by means of a suitable switch 101. The low pressure pipe 92 is also connected with the mercoid 93 by means of a by-pass pipe 100 .so that whenever the `pressure within the evaporator reaches a predetermined high degree Fahrenheit, the mercoid is tripped andthe electric circuit is closed automatically starting the electric motor for driving the pump. Just as soon as theftemperature within the. refrigerator has again reached its predetermined low degree Fahrenheit, the inercoid is again tripped and the electric circuit to the motor 65 is opened.

llVhat l claim is:

1. In a. pump of the class described, pirton driving mechanism including a pair of arms having facially slotted heads at each end thereof and disposed at 'right angles to the center line of the piston driving mechanism, and means to move the driving` mechanism in fixed circular orbital paths in sliding relation with the pistons.

2. In a pump of the class described, piston driving mechanism including arms having facially slotted heads at their outer ends and disposed at right angles to the stroke of the pistons and in sliding connection therel (lt) l In with to maintain the longitudinal centerline of the driving mechanism in parallel relation With the axis ot the pistons during the full stroke ot the. pistons'in 4either direction.

3. A pump of the class described including aligned cylinders and pistons reciprocable therein, supporting means for the cylinders, driven means, side driving members having connection Withl driven means and with the pistons for imparting reciprocating movement to the pistons, said driving-members being so disposed that the longitudinal center line thereof retains parallel relation with the aXisof the cylinders during the full stroke of the pistons in either direction.

1l. ln a pump construction including` aligned cylinders, pistons withinthe cylinders, a pair ot eccentric-s, means `for rotating the eccenti'ics, elongated means connecting each eccentric with the pistons for reciprocating' the pistons and retaining the longitudinal center lines of said means'in parallelV relation to the axisy ot" the cylinders at all points ota revolution of the ecceiitrics.

5. In a pump construction including` aligned cylinders and pistons, Wrist pins carried near the'outer ends of the pistons, eccentrically driven side members embracing the cylinders and means for connecting' the Wrist pins With the ecccntrically driven members for holding the longitudinal 'centerline ot the driven members in parallel relation with' the axis of theV cylinders at all points of the stroke ot the pistons in either direction. 4

6. In a pump structure including aligned cylinders and Epistons therein, a pair ot eccentiics, means for rotatingthe eccentrics, means movable with the pistons and disposed at right angles tothe pistons on opposite. sides of the cylinders, driven meansmounted upon the eccentrics midway their length having` sliding connection with the means movable ivitli the pistons forl imparting reciprocating movement to the pistons and to maintain the longitudinal center line of the driven means parallel with t-he center line oLt the pistons at all points of a revolution of the eccentrics.

7. In a pump of the class'described includi ing aligned cylinders and pistons therefor, wrist pins'ffor said pistonspassing through slotted 'openings in th-e'side Walls of the cylinders, piston driving mechanism comprising slide members carried by the wrist pins, means for slidably mounting the slide` menibersupon the ycylinders to prevent rotary displacement thereof," ecceiitrics, means for rotating the eccentrics and connections between the eccentrics and the 'slide members tor'reciproc'ating the pistons, the longitudinal center line of said connections being maintained in parallel relation With theaxis of the cylin-l ders at all points of a revolution of eccentricsv but permitted to rise'and Jfally with relation rocating movement'to lthe pistons in the same direction upon rotary movement of the ec 9L In a pump structure, aligned cylinders having outlet openings, a hollow' piston for each cylinder having a. head at each end, said pistons being provided with slotted intake slotted openings inthe upper Walls ofthe cylinders, valves in the inner heads ol" the pistons and means movable in circular paths upon opposite sides oi the cylinders having connection with the pistoiisfor impart-ing reciprocating movement thereto.

l0. In a pump, the combination olla cylinder, a piston therein, a'vvrist pin for' said piston, means for controlling the'admission oit' a charge to the `cylinder through the Walls of the cylinder and piston, driving eccentri'cs on opposite sides oit' ythe cylinder and connections between the eccentrics and the `ivviist pins, theeiids of said connections having slidingmovemeiit'at valright angle'to the. stroke of the piston.

ll. in a` pump construction includingY a cylinderY and a piston therefor, `iifiechani'sni toi' reciprocating the pistonv consisting of a driven eccentric, a float-ing Wrist rpin vcarried bythe piston ande-xtending at opposite ends through-and beyo-ndthe sidewallsv thereon cross heads positioned upon the ends of the Wrist pin,.ineans' to prevent rot-ation of the crossheads'and coi'inectionsbetween each eccentric and each cros'shea'd, the'afXis otlsaid connect-ions being maintained in parallel relation to the axis oit' the cylinders at all points y ofa revolution ot' the eccentrics.

' 12. 'In a pump structure, cylinders, pistons workable in said cylinders, Wrist pins for saidpistons, intake ports leading throughthe cylinders and pistons to the conufriession cliainbers'oi" the cylinders, outlet ports orthe cylinders, la pair of side eccentrics, driving means, cross heads carried by the Wrist pins and means for transformingrotaiymotion'of the eccentrics into reciprocating motion at the pistonsv by iiitefrventioiiof the driving means and cross heads intorectilineai motion at all pointso a revolution of the eccentrics.

l13. In a pumpstructure, a cylinderl block having aligned cylinders, a rotatably mounted driven shaft passing transversely through the cylinder block adjacent the inner ends of the cylinders, pistons working Within said cylinders, driving means actuated byV said Vopenings in their upper Walls registering with `mounted connection With the cross heads for alternate sliding movement thereon at a right angle to the movement of said cross heads for imparting reciprocating movement to the pistons.

M14. In a `pump structure, a cylinder block having aligned cylinders, a rotatably mounted driven shaft passing transversely through the cylinder blockv adjacent the inner ends of the cylinders, pistons Working within said cylinders, driving means actuated by said driven shaft, Wrist pinscarried by the pistons, the ends of Whichextend through slotted openings in the Walls of the cylinders, cross heads carried by the ends of said Wrist pins and said driving means having slidably mounted connection with the cross heads for alternate sliding movement thereony at a right angle to the movement of said cross heads for imparting reciprocating movement to the pistons, a casing forV wholly enclosing the aforesaid instrumentalities, an intake port and outlet port for said casing, said intake o ening communicating with the chamber of t e casing, the interior of the pistons and with the cylinder and the outlet port communicating with the cylinders only.

.15.. In a pump structure including aligned cylinders, pistons therein, inlet lport and outlet p0rts,-of a rotatably supported driven shaft, eccentrics fixed to said shaft on opposite xsides of the cylinders, driving members mounted upon said eccentrics,v WristA pins passing through the pistons near the outer ends thereof and passing through opposed slotted openings in the cylinders, cross-heads carried by the ends of said Wrist pins on opposite sides of the cylinders, guide bars integral With the cylinders for mounting said Wrist pins, facially grooved driving heads at the ends ofthe driving members mounted upon said cross-heads for vertical reciprocating-movement thereon to impart horizontal reciprocatingr movement to the pistons through the rotary movement of the eccentric embracing the driving members midway their ends. l

16. In a pump of the class described, a cylinderV block, pistons Within the cylinders,

VWrist pins for said pistons andextending beyond the Walls of the cylinders, cross heads positioned upon the ends of the Wrist pins, driven means, eccentrics fixed to said driven means, driving means mounted upon the eccentric Within which they rotate midway the ends of the driving means and said driving means having facial grooves dlsposed at a right angle to the axis of the cylinders vand sli'dably mounted upon said cross-heads for imparting reciprocating movement to the pistons during rotary movement of the eccentric and to maintain the longitudinal center line to the axis of the cylinders at allpoints of the revolution of the eccentric and said vpistons including relatively moving members affording connections between the driving means and the pistons and causing the center lines of the drivine` means to maintain Dar- 7 allel relation with the axis oitl the cylinders at all points `of the revolution of the eccentrics.

18. In a refrigerator pump structure, a hollow casing having an inlet port and an outletport, aligned cylinders disposed Within and fixed to the casing having communication with the outlet port and with the inlet port, the latter through t-he chamber of the casing, slotted means for permitting a charge to the compression Chambers of the cylinders through the pistons during the intake stroke of the pistons, a rotatably supported driven shaft, a pair of eccentrics fixed to said shaft on opposite sides of the cylinders, driving members, heads arranged at the ends of the driving members having. facial slots, said driving members being mounted upon said. eccentrics midway their ends for imparting reciprocating motion to the driving members, a Wrist pin carried near the outer end of each piston, the ends of said Wrist pins extending beyond the Walls of the pistons and passing through slotted openings in the side walls of the cylinders and members mounted upon the ends of the Wrist pins With their longitudinal axis disposed at a right angle tothe axis of the Wrist pins and mounted for horizontal reciprocating movement upon the side Walls of the cylinders to maintain the center line of the driving members in parallel relation With the center line of the cylinders during every degree of the revolution of the eccentrics. f

19. In a pump structure, a cylinder including a compression chamber having an outlet and a housing Within Which the lcylinder is fixed, a hollow piston in said cylinder reciprocable relative thereto, an automatic valve mounted in the inner head of the piston, an

intake passage in the cylinder communicating at its intake end with the inte 1ior of the housing `and at its discharge `end With a slotted opening in the Wall of the piston and a bafiie structure adjacent the intake end of the nally slotted openings, hollow pistons reciprocable within the cylinders having slotted intake ports in their upper walls, valves disposed in the inner heads thereof, lateral eX- tensio'ns upon the pistons working 'in the slotted opening of the cylinders, slide bar* upon the outer sideffaces of the cylinders, cross-heads positioned upon the lateral eX- tensioiis and mounted upon said slide bars,

said cross-heads being united upon opposite.. sides of the cylinders, driven eccentrics, pistons connecting and driving means mountedV midway their ends upon the eccentrics and having their outer ends slidably mounted upon the cross-heads in suoli a manner that the axis of the piston connecting means is disposed in parallel relation to the aXis of the.

cylinders at all points of a revolution of the eccentrics. K

2l. A device of the class described comprising a housing having an inlet, a pair of aligned cylinders en bloc removably fixed within the housing and each having an inlet and an outlet passage,`a valve for each cylinder outlet passage, a piston having an inlet and an outlet passage within each cylinder, an automatic valve for eachpiston outlet passage, baffle means within the housing adjacent each cylinder inlet passage and means for reciprocating said pist-ons in unison to compress toward the inner ends thereof.

22. A device of the class described comprising a casing made of two sections having an inlet and an outlet passage and a compressor having horizontally disposed aligned cylinders rigidly but removably carried by one of .the casing sections through a three point connection therewith. 1

23. A device of the class described comprising a casing made of two sect-ions having an case, a compressor having aligned pistons rigidly but removably mounted wholly Within the casing, said compressor having inlet passages coininunicating with the interior of said casing and having outlet passages communicating withthc outlet passage of the casing.

2a. ln a compressor, a housing having a fluidtiglit chamber formed to receive a lubricant and also a fluid above the surface of the lubricant, pumping mechanism arranged in the chamber and having an inlet projecting thereabove andin free communication with the part of the chamber above the level of the lubricant, and means for operating the pumping mechanism having appart Athereof submerged in the lubricant.

25. In a compressor, a housing having a tluidtight chamber` formed to receive a lubricant and also a fluid abolire the surface of the lubricant, a multiple cylinder pump in the chamber having a plurality of separate inlets projecting thereabove and in free communication with the part of the chamber above the level of the lubricant, and a common meansfor actuating the pumping elements having a part thereof submerged in the oil.

26. In a compressor, a housingY having a fluidtight chamberformed to receive a body of the lubricant and also a fluid above the surface of the lubricant, said housing havingl a pocket disposed above the surface of the lubricant, a pump in the chamber having an inlet pipe which latter entends above the top of the pump and intothe pocket, and means to actuate the pump having a part thereof submerged in the lubricant. f

In testimony whereof I have hereunto aliixed my signature.