US2360876A - Compressor and the like - Google Patents

Description

AOct. 24, 1944. R M. ||V|D COMPRESSOR AND THE LIKE 3 Sheets-Sheet l Filed March 14, 1941 IsEI.. |12.: i Il ILif III.'

m 'ENTOR Oct. 24, 1944. R. M. HvlD COMPRESSOR AND THE LIKE 5 Sheets-Sheet 2 Filed March 14, 1941 mm @i 5&5 v IVENTOR, BY 234/ VM oct. 24, 1944. R- M |'|V|D oMPREsSOH AND THE LIKE Filed March 14, 1941 s sheets-sheet s'v H Hi INVENTOR. W

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driving motor within ation of the compressor valves, and

patented Oct. 24, 1944 UNITED STATES PATENT OFFICE 2,360,876 COMPRESSOR AND THE LIKE Rasmus M. Hvid, Wilmette, Ill. Application March 14, 1941, serial No. assale 14 claims. (c1. aso-173) This invention relates to compressors, pumps, pressure motors and the like, more particularly to motor-compressorunits for use in hermetically sealed casings or housings, and the invention has for an object the provision of compact and eicient compressor or pump units of this character.

It is becoming more and more the accepted practice in the construction of refrigerating apparatus, particularly household refrigerators of the type utilizing a closed compressor-condenserexpander cycle, to house the compressor and its a. permanently and hermetically .sealed casing. 4Such arrangements of course require-a compact construction of the mtor and compressorunit which will be troublefree and capable of operation over long periods of time without servicing or repairs. While various compressor umts have heretofore been prosystems, problems have been encountered due to failure of the compressor parts or to faulty opersomething is yet to be desired in motor-compressor. units of this character.

It is a further object of this invention to pro vide a 'compact and eilcient-valveless compressor, pump or motor of the reciprocating type `having intake land discharge ports controlled solely by movements imparted to the reciprocat- -ing piston, and wherein the necessity for sepais entirely eliminated. invention in one form `I rately operated valves- In carrying out my provide a compressor ing in the same axial direction but offset from the rotating drive shaft, a piston mounted in the cylinder for both rotary andreciprocatory movement therein, and a driving connection between the rotating shaft and the piston for moving the piston through one complete rotation during each complete reciprocation thereof. Suitable valve ports are provided in the cylinder wall and in having a cylinder extend-,

Fig. 3 is a horizontal sectional view taken substantially along the line 3 3 of Fig. 1;

Figs. 4 and 5 are fragmentary vertical sectional views taken along the lines 4 4 and 5 5, respectively, of Fig. 3;

Figs. 6 and are similar vertical sectional views taken along the lines 6--6 and 'I-, respectively,

of Fig. 2;

Fig. 8 is a detail sectional view taken substantially along the center line of the wrist pin for the reciprocating and rotating pistonv shown in posed and adopted for use in such refrigerating ',20

mounted on a suitable shaft one face of the piston, which valve ports are so` I that the rotary properly timed disposed in cooperative relation movement of the piston eiects suction and compression strokes as the piston reciprocates.

For a more complete understanding of my invention, reference should now be had t-o the drawings, in which:

Fig. 1 is a vertical sectional view taken substantially along the line I-I of Fig. 2;

Fig. 2 is a horizontal sectional view taken along the line 2-2 of Fig. 1;

l Fig. 1; and

Fig. 9 is a somewh'at diagrammatic elevational sectional view showing a modification of theinvention as applied to an internal 'combustion engine.

Referring now to Figs. 1 to 8, inclusive, of the drawings, the invention is shown as embodied in a hermetically sealed motor-compressor unit wherein the hermetically sealed casing, which is formed of an upper shell I0 and a lower shell II, forms the low pressure side of the refrigerating apparatus. The motor, which may be of standard constructioni comprises a stator winding I2 mounted upon a laminated stator frame I3 within which is disposed the rotor I4, the rotor being I5 having an enlarged cylindrical head I 6 on its lower end. As shown, the stator frame I3 is mounted, with a pressed t, within the open upper end of a cupshaped supporting member or shell I'I, the lower wall of which is formed to provide a re-entrant portion I8 having a centrally located aperture therein through which the shaft, I5 of the motor extends.

Disposed within the re-entrant portion I8 of the supporting shell Il is a bearing ring I9 with- 1n which the cylindrical head I6 on the motor 'which is supported below the bearing ring I9 ing 2I by suitable bolts, as shown closure plate 22a.

As shown best in Figs. 1 and 2, the casting 2| 1s shaped to provide a vertically extending cylinder. 23 having an intake port 24 which com- 2 I aecomo j munlcates with an intake chamber 2l, and an compressor. this chamber is connected to theoutlet port 2l which communicates with an out. interior of the hermetically sealed casing by let chamber 21. Disposed Within the cylinder means of a port 33 which, as shown in Fig. 6. 22 is g piston 22, one wall of which is provided extends through the casting 2l, the bearing ring adjacent the lower end of the piston with a port 5 I9, and the portion I8 of the shell Il, so that Il arranged to cooperate with the intake and the communication occurs just below the motor outlet porta 24 and 26, respectively. in a manner and at a considerable distance above the body which will be more fully described hereinafter. of oil. Also extending through a wall of the The piston 2l is hollow. 3S ShOWn beef? in Fig. 1. shell l0 is a discharge conduit or pipe 40 which and is provided intermediate ite ends with e euit- 10 is connected to the nigh side of the refrigeret able wrist pin 33 to which is pivotaliy connected ing system and tothe discharge chamber 21 oi a connecting rod Il, the ODDOS te @mi 0f the i011- the compressor, as shown best in Figs. 2 and 7. neel-.ins rod being piveteily connected, preiera suitable ntting il (Fig. 'n providing a presably by means 0f a bail and Socket 10mi?, t0 the sure-tight connection between the conduit MI enlarged head I3 on the motor shaft l5. The l5 and the discharge chamber 21.

ball 32. Which iS formed 0n the Olii/er end 0f th In order to insure that the piston and cylinder connecting rod 3l. is lcdted Within 9 4503i??l 33 are properly lubricated, a small oil pump is proiermed in one face. of the heed i6 and reteined vided for transferring lubricating uuid from the therein by B Suitable disc which is Provided body of oil contained in the hermetically sealed with it Spherical f 35 and iS sitted at 35 as 20 chamber to the walls of the cylinder 23 under shown best in Fig. 3. t0 Permit the desired move suitable pressure. This oil pump is formed, as ment of the connect-i118 rod 3|, the Socket 33 and shown best in Figs. 1 and 3, by cutting back a the'fce 33 0n the disc u forming 3 Substantially narrow band on the upper portion of the enspherical seat for the ball 32. 4 larged head i8 to provide an eccentric surface The Socket 33. in which the bagu 32 0n the up' 25 42. Engaging this eccentric surface is a springpei' end 0f the imecting 1`d 3| 1S located i5 on" pressed follower 43 which-ls located in the bearset from the axial Center 0f the Shaft and the mg ring 's' an intake duct being disposed on l enlarged head I3 a distance considerably @Wafer one side of the spring-pressed follower I3 and than -thel QTY-Set distance betwen the cenlf Ime a discharge duct 45 (Fig. 3) being disposed on of the shaft and the center hne of the cylinder 30 the opposite side of the follower g3 23.- This relation between the socket 33, the cen- AS shown in Fig. 1,- the intake duct' 44 extends ter line of the shaft l5 and the center line of downwardly through the castingv 2l to a point the cylinder 231s highly desir'bie in Order t m' below the level of the sure that the socket 33 never occupies a position within the casing and, as shown m plm 4, the coincident with the center line ef the pieten 2 as discharge duct 4s communicates with on -oil in which position retetlen 0f the Pieton would groove 4s which extends about the well of the .be possible independently 0f any movement 0f cylinder 2i. when the shaft is and the heedthe head I6. l I6 rotate in the direction indicated by the ar- When the Darts are in the Position Shown m row in Fig. 3, the oil pump provided by the ecmglrthe Piston f" is at the upper end of its 4 centric portion l2 and the follower 43 will cause itithrgehellgo lieloci 1% -h'svehgprigg oil to be drawn up through the duet 4t and exthe center une of the piston 28 so that the ,my pelled under pressure through the discharge duct tm wm occupy its lowermost position in the l5. and it will be apparent that, by providing oil D grooves in the various faces of the head I6, the Wunder '23' During the next 180 of movement 45 running surfaces between the head, the bearing of the head I3 the piston will be returned to the upper 'end of its stroke. nach rotationM of the cnembers s and may be effec' 2315i: dg, :u' tspghs gvz With the above description of the various elemed m control the intake and discharge of the 56 ments in mind, itis believed that a complete ungas to be compressed Within the cylinder 23 If derstandirig of this invention may be had from the onset distance of the socket 33 fmm'the a description of the operation. As heretofore center litn of tiliie siliaft were only Slgi'illy gegedthhlgah Slr'thfeslwe'hgnggrtl greater an e o settance between e f omg; 213 5 :emettere: successes; geletehgigstgat tgistgnfeo and onecomplete reclprocation of the piston 28 ball and socket approach a position closely adjairsmg'ah revolution 0f the Shaft |5- During centthe center line of the piston and cylinder. th m a otr; the han 32 on the upper end 0f Accordingly a substantial difference in these o e conne@ g rod 3i pivots in its Socket 33' offset, distances is preferred, as shown and during this pivotal movement moves toward The hermetlglly Sealed casing formed by the and away from the center line of' the cylinder 23 shells lll and H, within which the motor-com- S0 as t0 Templi-*Cate the Piston.

presser unit is located,'is connected to the low AS ShOWn best in Fig. 2, the intake Dort 24.

body of lubricating iiuid pressure Side of the refrjgerating system which establishes Communication between the inmelms of a. suitable lnlet pipe 31 which extends take chamber 25 and the lower portion of the through a wall of the shell l0 adjacent the up- Cylinder 23 When the Dort 29 in the Piston iS per end o! the casing, and the lower portion of Opposite the port 24, extends about a substanthe casing contains a. body of lubricating lluld tial portion of the circumference of the cylinder, 'which extends approximately to the level indi- 70 i. e., between the shoulders 52 and 48 (Fig. 2). cated by the line 38.' During operation of the Thepistcn 28 occupies its upper dead center p0- motor-compressor unit this body of lubricating sltion when the port Ml in the piston is subfluid will be subjected to considerable disturb- Stntiaily opposite the shoulder 5I and accordance, and in order to insure that the lubricant ingly the port 29 is in communication with the la not drawn into the intake chamber 25 of the 75 intake port 2l during substantially the entire andere suction stroke. Shortly after the piston 28 has the port 29 in the wall of the piston moves past the shoulder 48, whereupon communication between -the cylinder 23r and the intake chamber 25 is cut ofi and pressure begins to build up within the cylinder 23. The feature of maintaining the inlet port 24 open for a short time after the piston 28 has passed the dead center position affords better charging of the cylinder than would otherwise be obtained. When the intake port 29 passes the shoulder 49 (Fig. 2) in the cylinder wall, .the cylinder` 28 is placed in communication with the discharge passageway 26.

Pressure continues to build up as the piston 28 is rotated and reciprocated, andthe compressed gas is thus discharged 'from the cylinder 23 through the discharge port 26 and into the discharge chamber 21. Disposed between the discharge port 26 and the discharge chamber 21 is a normally closed spring-pressed check valve 66 'which opens as soon as the pressure in the cylinder 23 exceeds the pressureat which the check valve will open. It will of course be understood that the back pressure in the chamber 21 and the pressure'exerted by the check valve spring cooperate to determine the total pressure at which .the check valve 50 will open. The purpose of this check valve is primarily to prevent circulation between the high and low sides of the compressor during idle periods, and it will o1' course be seen that the compressor will function without it inasmuch as positive opening and closing of the intake and discharge ports is accomplished by rotation of the-piston 28. When the discharge port 29 passes the shoulder 5|, communication between the cylinder 23 4and the discharge port 26 is terminated and, as previousvly indicated, this point preferably corresponds approximately with the lower dead center position `oi. the piston. `Further rotation of the pis- Iton as it begins its suction stroke causes the port 29 to'pass the shoulder 52 in the cylinder wall and again establish communication between the cylinder 23 andthe intake chamber 25 through the intake port 24. It will be observed that the timing of the suction and discharge periods is positively controlled by the movement of the` port 29 in the piston 28 past the various shoulders in the cylinder wall, and is independent oithe check valve 58.

In order to insure that a body of compressed liquid is not trapped behind the'check valve, the shell within which the spring of this check valve is located is preferably provided with a' plurality of holes 63 as shown in Fig. 2.

It will now be apparent that a motor-compressor unit embodying the present invention is characterized by extreme compactness and the utilization ofv` only a few moving parts which may be inexpensively manufactured. The absence of any separately operated mechanical valves eliminates the necessity of separate setting and timing operations, and materially reduces theprobability of failure of the compressor to operate after being placed in service.

While the above described construction is particularly useful as a compressorfor refrigeratl ing apparatus, it may of course be utilized either as a compressor for any desired gaseous mepassed its upper dead center position, however,

dium or as a pump for any liquid medium which it is desired to transfer from one place to another under pressure. necting the port 26 to a proper sourceof air or Furthermore, merely by conmay be reversely driven and caused to operate as an air motor for driving any suitable mechanism connected to the shaft I6. In Fig. 9 there is shown somewhat diagrammatically an internal combustion engine of the two-stroke cycletype wherein 'a cylinder 65 is provided with an intake port 66am adischarge port 61, the piston the cylinder 68 being connected by a suitable connecting rod 66 to an enlarged head 6| on the engine shaft 62. The engine shaft 62 is supported in suitable bearingsv 63, as shown, and the enlarged head 6| on the shaft 62 is provided with a spherical socket 64 oifset from the center line of the shaft 62 adistance somewhat greater than the oliset distance between the cenport 5B is connected by In this embodiment of the invention the ro-Y tary movement of the piston 58 is not utilized to control the intake and discharge ports, the'operation beingmuch the same as inv heretofore known two-stroke cycle internal combustion enengines, and the discharge ,port 51 being arranged to open a short time prior to opening of the intake port 6'6. Assuming that the piston J8 is at the upper end of its stroke and that ignition of the charge takes place so as to force the piston 58 downwardly, it will be observed that as the piston moves downwardly the Vcombustible mixture contained in the casing 61 will be compressed. When the discharge port 51 ls-uncbvered the burned gases will be discharged through the port 51, and when further downward movement of the piston 58 takes place the intake port l56 is uncovered and a fresh charge under pressure will flow` from the casing 61 through the conduit 66 and the intake port 56' to the cylinder 65. Upon subsequent upward movement of .the piston 59 both the intake and the discharge ports will be closed by movement of the piston and compression of the charge trapped in the cylinder 56 will thereupon occur` in preparation for another iiring stroke. At the same time a suction is created in the chamber 61 so as to open the ap valve 68' and draw a fresh charge from the carburetor 69. Reciprocation of the piston 59 of course causes the shaft 62 and the head 6| to be rotated by the connectingv ro'd 60, the movement being substantially the reverse of that utilized inlthe compressor construction heretofore described in that reciprocatory movement is transformed into rotating movement, while in the compressor,l rotation of the driving motor causes reciprocation of the compressor piston.

While I have shown,particular embodiments of my invention, it will be understood, of course, that I do not wish to be limited thereto since many modifications may be made, and I, there- 1. In a device of the character described, the combination of a cylinder, al piston mounted in said cylinder for reciprocation and rotation 58 -which is located within end of the connectconnection between said nailed in said bearing said cylinder and therein, a connectlng'rod'plvoted at one end to said piston and against rotation with respect to said piston. a shaft rotatable on an axis substantially parallel to but offset from the axis of said cylinder, and means pivotally connecting the opposite end of said connecting rod to said shaft for rotation therewith, the pivotal shaft and said end of assume t 4. The combination set forth in claim 3 where!v said rod being radially spaced from the axis of said shaft a distance greater than the offset distance between the axis of said shaft and said cylinder whereby rotation of said shaft at a constant angular velocity causes said piston to reciprocate and simultaneously rotate through a complete revolution in said cylinder with a cyclically varying angularvelocity during each reciprocation thereof.

2. In a device of the character described, the combinationv of a cylinder having circumferentially spaced and circumferentially extending slots in the side wall thereof forming intake and exhaust ports for said cylinder, a piston in said cylinder having a longitudinally extending slot in one side thereof for selectively connecting said intake and exhaust ports to theinterior of said cylinder beyond said piston when said piston is unidirectionally rotated in said cylinder, a connecting rod pivoted at one end to said piston and restrained against rotation with respect to said piston, a shaft rotatable on an axis substantially parallel to but offset from the axis of said cylinder, and means pivotally connecting the opposite end of said connecting rod to' said shaft for rotation therewith, the tween said shaft and said rod being radially spaced from the axis of said shaft a distance greater than axes of said shaft at a substantially constant angular velocity and said cylinder whereby rotation of said shaft causes said opposite end of said connecting rod 'to move in a circular path offset from the axis of said cylinder simultaneously to nnidirectionally rotate said piston with a cate said piston.

3. In a motor compressor unit, the combination of a cup shaped supporting member having a concentric re-entrant portion in the lower wall thereof and a central aperture in said re-entrant portion, a motor having a stator positioned within said cup shaped member above said lower wall pivotal connection be-4 to the oifset -distance between the eyclically varying angular velocity and reciproand a rotor within said stator, a shaft extending through said aperture for supporting said rotor, an enlarged circular head on said shaft within said re-entrant portion of said supporting member, a bearing ring in said re-entrant portion surrounding said circular head, a cylinder block po'- sitioned beneath said ring and said head and rigidly secured to said ring. and said supporting member whereby said head is supported between said block and said supporting member and jourrlng,'said block havinga cylinder formed therein extending substantially parallel to the axis of said shaft but offset theref rm,a piston in sad cylinder, a connecting rod having' itsv opposite ends respectively pivotally connected to said piston and to said head, the pivotal connection to said head being radially spaced from the axis vof said shaft a distance unequal to the oifset distance between the axis of said shaft and said rod being restrained against rotation relative to said piston whereby rotation of said head by said motor causes' said piston simultaneously 4tc reciprocate and rotate in timed relation in said cylinder.

in said cylinder is provided with circumferentially spaced slots in the side wall thereof forming intake and exhaust ports respectively. and said piston is provided with a longitudinal slot extending to the head end thereof for selectively connecting said ports to the interior of said cylinder beyond the head end' of said piston as said piston is rotated and lreciprocated in timed relation.

5. The combination set forth in claim 3 wherein said enlarged circular head includes an eccentric portio a spring pressed follower supported in said bearing ring engaging said eccentric portion to form therewith a rotary pump, means forming intake and discharge ports on opposite sides of said follower, and means respectively connecting said intake and exhaust ports with a body of oil and with said cylinder whereby .presiii'gdlubcation of said cylinder and piston is pro- 6. In a motor compressor unit, the combination of substantially cup-shaped supporting means having a concentric re-entrant portion at the bottom thereof and a central aperture in said re-entrant portion, a motor having a stator positioned within said cup-shaped means surrounding said re-entrant portion and having a rotor within said Ystator above said re-entr'ant portion. a shaft journaled for rotation extending through said aperture for supporting said rotor, radially extending means on the end of said shaft within said re-entrant portion, a cylinder block rigidly secured to said cup-shaped means positioned below said re-entrant portion and having a cylinder therein' extending substantially parallel to the axis of said shaft but offset therefrom a distance less than the length of said radially extending'means, a piston in said cylinder, a connesting rod having its opposite ends respectively pivotally connected to said piston and to said radially extending means, said rodv being restrained'against rotation relative to said piston whereby rotation of said shaft and said radially tending-to the head end thereof for selectively connecting said ports to the interior of' said cylinder beyond the head end of said piston as said piston is rotated and reciprocated in timed relation.

8. In combintion, a driven element mounted for rotation about an axis and for reciprocation along the axis of rotation, a. driving member mounted in spaced relation to one end of said driven member for rotation in a circular path about an axis said axis of said driving member being parallel to but laterally offset from the axis of said driven member, the offset distance being less than the radius of said circular path, a connecting rod, means connecting said rod to said driving member for universal pivotal movement and rotation with' respect thereto as said driving member is rotated, and means for connecting .the

other end of said rod to said driven element for' by rotation of said driving member at a constant angular velocity eiects simultaneous rotation of said driven member continuously in one direc- -tion with a cyclically varying angular velocity men't therein, a connecting rod pivoted at one end to said piston and restrained against .rotation with respect to said piston, and means for 4moving the opposite end of said connecting rod in a circular path at `a substantially constant angular velocity about an axis of rotation, said axisl of rotation being substantially parallel but offset from the 'axis of said cylinder to reciprocate said piston and impart thereto a rotary movement, said offset distance being unequal to and less than twice the radius of said circular path to impart to said piston a cyclically varying angular velocity which during a portion of the piston travel is greater than said constant angular velocity.

A10. Ina device of the character described, the combination of a cylinder, a piston mounted in said cylinder for reciprocatory and rotary movement therein, a connecting ro'd pivoted at one end to said piston and restrained against rotation with respect to said piston, and means for moving the opposite end of said connecting rod in a circular path at a substantially constant an- Y gular velocity about an axis of rotation, said axis of rotation being substantially parallel but offset from the axis of saidcylinder to reciprocate saidl piston and impart thereto a rotary movement, said offset distance being unequal to and less than twice the radius of said circular path to impart to said piston a cyclically varying angular velocity whichduring a. portion of the piston travel is greter than said constant angular velocity, said cylinder having spaced intake^and discharge ports in the wall thereof, said piston,-

having a slot therein for selectively eiecting opening and cut-off of said ports, said ports and said slot being so related that cut-oil of said ldischarge port is effected during said portion of the piston travel whereby quick cut-off and a large lap is provided. l.

1l. In a device of the character described, the combination of a cylinder, a piston mounted in said cylinder for reciprocatory and rotary movement therein, a connecting rod pivoted at one end to said piston and restrained against rotation with respect to said piston, and means for moving the opposite end of said connecting rod in a circular path at a substantially constant angular velocity about an axis of rotation,v said axis of rotation being-substantially parallel but -olset from the axis of said cylinder to reciprocate said piston and impart thereto a rotary movement, said oii'set distance being unequal to ving edge 'of said inlet portl being so located relative to said piston slot that said slot eiects' cutoff of said discharge port and opening of 4 said intake port during said greater velocity portion `of said piston travel whereby quick cut-off and Y quick opening of said respective ports is provided.

12. In a device of the character described, the combination of a cylinder, a piston mounted in said cylinder for reciprocation and rotation therein, a connecting rod pivoted at one end to said piston and restrained against lrotation with respect to said piston, and means including a rotatable shaft' for moving the opposite end of.

said connecting rodin a circular path at a substantially constant velocity, the axis of said shaft befng substantially parallel to butoffset from the axis of said cylinder, the radius of said circular path being substantially greater than the oiset distance simultaneously to reciprocate said piston-and rotate said piston continuously in one direction in said cylinder with a vcyclically varying angular velocity which during a portion of the piston travel is greater than said constant angular velocity.

13. In a device of the character described, the combination of a cylinder, a piston mounted in said cylinder for reciprocation and rotation therein, a connecting rod pivoted at one end to Asaid piston and restraineda'gainst rotation with respect to said piston, and means including a rotatable shaft for moving the opposite end of said connectingv rod at a constant angular velocity in a circular path, the axis of said shaft being substantially parallel'to but offset from the axis of said cylinder, theradius of said circular path being substantially vgreaterthan the offset distance simultaneously -to rotate said piston through complete revolutions in said cylinder with a "cyclically varying angular velocity and to reciprocate said piston, said cylinder having in the wall thereof intake and discharge ports selectively controlled by the complete revolutions of'said piston during each reciprocation thereof.

14. In a device of fthe character described, the combination 'of a cylinder having circumferentially spaced intake and discharge ports in the side wall thereof, a piston in said cylinder having i ly connecting said ports with the interior of said cylinder beyond the head end of said piston, a

connecting rod pivoted at one end to said piston and restrained against rotation with respect to said piston, and means including a rotatable shaft for moving the opposite end of said conand less than the radius of sai'd circular path to impart to said piston a unidirectionall cyclically varying angular velocity which during a portion of the piston travel is greater than said constant angular velocity, said piston having a slot in one wall extending tothe head end thereof, said cylinder having circumferentially spaced intake and discharge ports in the wall thereof with the cut-off edge of said discharge port and the opennecting rod at a constant angular velocity in a substantially circular path, the axis of said shaft being substantially parallel to 'the axis of said cylinder but offset therefrom avdistance substantially less than the radius of said circular path to reciprocate said piston andsimultaneously rotate said piston continuously in one direction in said cylinder with a cyclically varying angular velocity which during cut-oil' of said discharge port is greater than said constant angular ve- -locityv whereby quick cut-oil is obtained and a large lap is quickly provided to prevent leakage Iback through saiddischarge port.

Rasmus M. Hvin.

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