US3136479A - Valve for machines having a reciprocating piston - Google Patents

Description

June 1964 N. E. B. LARSSON 79 VALVE FOR MACHINES HAVING A RECIPROCATING PISTON Original Filed March 23, 1959 2 Sheets-Sheet l 14 75 7 Q '-l5 i 27 8 27 JW/Z/ iVI'f/z/ June 1964 N. E. B. LARSSON VALVE FOR MACHINES HAVING A RECIPROCATING PISTON 2, Sheets-Sheet 2 FIG. 71).

Original Filed March 25, 1959 FIG. 7a.

United States Patent ,1 5, 79 VALVE FOR MACHINES HAVING A RECIPROCATING PISTON N r k. 'et awso qdemi msxa .15

a i we en Original application Mar. 23, 1959;, Ser. No. 801,232. Dividedand "this application May 29,1961, Ser. N0 113,338

1 Claim. (Cl. 230-229) The present invention relates to machines haying a reciprocating piston, such as for instance compressors, and more particularly to a valve mechanism, for such machines of a type including an annular or polygonal valve seat having substantially radial openings for the passage of thework in g medium, and an. automatically operating valve body provided in front of said openings or surroundingthe valve seat for controlling the passage of a m m t rou h said op n gs- A feature of the inyention involves that the valve body and the valve seat are i qtatablym ounted with relation to each other in order to permit unloading of the machine by uncovering said openings.

The subject matter of the present invention is disclosed in 'my pending applicationSerial No. 801,232, filed March 23,1959, fro m which the present application is divided out.

In the accompanying drawing FIG. 1 is an axial section of the piston and the uppermost portion of a compressor having a valve mechanism according to the invention. FIGS. la and 1b are diametrically opposite portions of an axial cross-sectional view of a valve mechanism according to the invention used as intake valve for a compressor cylinder. FIGS. 2 and 3 are elevations looking from inside of a portion of said valve mechanism with the valve seat and the valve body shown in two different positions with relation to each other. FIG. 4 is a top plan view of FIG. 1a with certain portions shown in horizontal section. FIGS. 5 and 6 are top plan views of a detail portion of FIG. 4 with the valve body shown in different positions.

With reference to FIG. 1, the numeral 1 designates the cylinder wall of a piston type of compressor, 2 is the up and down movable piston thereof, and 3 is a pivot for hingedly connecting a piston rod, not shown, to the piston 2. Supported on the top edge of the cylinder wall 1 is an annular member 4 forming an extension of the cylinder Wall 1. Said member 4 is constructed and arranged so as to act as the seat of a valve mechanism for admitting to the cylinder the medium to be compressed therein by the action of the piston, said medium being hereinafter referred to as the working medium.

Resting on the top edge of the seat member 4 is an annular member 5 forming the top portion of the cylinder wall. Said annular member 5 is fitted in a boring in the compressor frame designated as a whole by 6 and is tightened therein by means of a sealing ring 7. Resting on the top edge of the wall member 5 is a yoke 8 which supports by means of a central bolt 9 and its head 10 a cylinder cover 11 having, in the embodiment shown, a curved lower surface and a plane upper surface.

Clamped between the cylinder cover and the yoke is a flat disc 12 having a downwardly extended hub portion 13 surrounding the bolt. Said extended hub portion bears upon the cover 11 so as thereby to maintain the disc 12 at a distance above the plane upper surface of the cylinder cover.

The cylinder cover 11, the disc 12 and the yoke 8 are all clamped together in the longitudinal direction of the bolt by means of a nut 14 engaging the threaded upper end of the bolt. A pressure spring 15 is inserted be- 3,136,479 Patented June 9, 1964 en e. yok a the pper Wall of a disc a chamri ch n els 1 p st e valve 18 n th r i ed t te may.

fu th r pa n o the. ischa ge. hamber. 6. v pe ings 21 in the yoke. 8.

Th va ve. seat member 4 s ormed w th a c r la y cylindrical internal surface for cooperating with a valve body. The seat member is shown as formed with periphera y pa ed x l rows. f pe res 22 s in ed in FIG. 4. The valve body for cooperation with the internal surface of seat 4 comprises an 'annularly bent strip 25 having ax a y, xt ng t gues t therein wit spaces 27 therebetween. Said tongues are normally located in register with the rows of apertures 22 so as to ye them and may. bar tated to unco e he. per ur 9 a al ow. Pass ge working med m reth ou h by bending inwardly, during thesuction stroke when the,

piston is moving downwards and the pressure decreases.

The inward or uncoveringbending movement of the,

tenan s s. im ted y s p rmetl' y an annular p jection 29 of an uppermost cylinder wall member 5.

. In order to effect a capacity regulation the apertures 22 may be completely uncovered by bringing the tongues 26 out of register with the rows of apertures 22. To this end the valve body 25 is rotatably mounted with relation to the valve seat member 4. For effecting a rotation of the valve body within predetermined limits is shown a snap by means of which such a rotation may be rapidly carried out during the suction stroke of the piston, since during this stroke the rotation is facilitated due to the tongues not being forced against the valve seat.

The turning mechanism comprises two concentric rings 36 and 37 situated on opposite sides of the lowermost portion of the seat member 4, said portion which is designated by the reference numeral 40 in FIGS. 1a and 1b being of a small radial width with relation to the radial width of the remaining portion of the seat member. Said rings 36 and 37 are connected together by means of a substantially radial pin 41 passing freely through a circumferentially elongate opening 42 formed in the seat portion 40.

Thus, by turning the ring 36 which is accessible from outside the inner ring 37 as well as the valve body 25 connected thereto may be rotated from the position shown in FIG. 2 into the position shown in FIG. 3 and back again. In order to prevent the valve seat member 4 from partaking in this rotation it is locked to the cylinder wall 1 by means of a substantially axial pin 43, FIG. 1b.

The valve body 25 and the inner control ring 37 therefor are split like piston rings in order to permit expansion due to increase of temperature.

The rapid rotary movement of rings 36 and 37 hereinbefore referred to may be effected by means of a ring 44 rotatably surrounding the ring 36 while bearing also against the lower surface thereof, as shown in FIGS. 1a and 1b. Said ring 44 may be rotated by movement in the directions of the arrows of an arm 45 connected, for instance, to a hydraulic controlling device, not shown. Inserted between the rings 36 and 44 at circumferentially spaced points thereof are spirally wound springs 46 the ends of which engage holes formed in the ring 36 and the ring 44, respectively.

To elfect setting of the valve body 25 into the inoperative position indicated in FIG. 3 the arm 45 is subjected to a power acting in the direction of the full arrow shown in FIG. 4; The resulting rotary movement of ring 44 puts the springs 46 under tension and, after reaching the position shown in FIG. 5, the springs are released during.

the suction stroke of the piston operating in the cylinder and moves the ring 36 rapidly in clockwise direction to the position shown in FIG. 6 corresponding to the position of the valve body shown in FIG. 3 in which the rows of apertures 22 are in register with the spaces 27. To restore the valve body to normal position with the tongues 26 in register with the rows of apertures the arm 45 is moved in the direction of the dotted arrow in FIG. 4,

causing the ring 44 to again tension the springs 46 and allow them to restore the rings 36 and 37 with the valve body to normal position.

Other quickly operating shifting device than that above described may be used without departing from the idea or scope of the invention.

each other, an annular valve body arranged in said valve seat and extending with its inner wall substantially in extension of the inner wall of said cylinder, said valve body having a plurality of am'ally extending tongues spaced angularly at equal intervals as said openings, a ring extending around the outside of said one end of said cylinder approximately opposite said valve body, said seat portion having an additional opening therein, means extending through said additional opening and engaging said ring and valve body to transmit movement between said ring and valve body, a set of springs operably engaging with their ends between said cylinder and said ring, and means for imparting circumferential movement to said ring to move said valve body angularly and to impart radial bias to said set of springs to cause said spring to quickly shift said ring and valve body to the operative or'inoperative position respectively of said valve tongues.

References (Jited in the file of this patent UNITED STATES PATENTS Germany Feb. 1,

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