US3124152A - Poppet-type valve construction - Google Patents

Description

2 Sheets-Sheet 1 I .37 lb 57 R W m w W M a mm H m 2, W 0,0 m m fi u 21,. d

March 10, 1964 w. H. PAYNE E'IPOPPET-TYPE VALVE CONSTRUCTION Filed March 24, 1961 w w 2 Wm y w. w

BY p W- ATTORNEYS.

March 10, 1964 w, H, P YN POPPET-TYPE VALVE CONSTRUCTION 2 Sheets-Sheet 2 'Filed March 24, 1961 fttlki William H. Payne, Olean,

'for use in compressors of the reciprocating piston type.

United States Patent 3,124,152 Patented Mar. 10, 1964 Free 3,124,152. POPPET-TYPE VALVE CONS'I'RIIQTEQN N.Y., assignor to Dresser Industries, Inc, Dallas, Tex., a corporation of Delaware Filed Mar. 24, 1961, Ser. No. 98,053

2 Claims. (Cl. 137--269.5)

This invention relates to an improved poppet-type valve construction and more particularly to a valve assembly While a valve assembly constructed in accordance with the principles of the present invention can be used either as a suction or discharge valve, it is particularly advantageous for use as a suction valve assembly in a compressor of the aforementioned type wherein the suction pressure is low, that is, around atmospheric pressure.

If the mass of a poppet valve is large and it is opened and closed repetitively, a relatively heavy spring, i.e. one having a high spring rate, is needed to provide sufficient acceleration to close the valve within the cyclic time permitted.

An important object of the present invention is to provide a poppet valve assembly in which the mass of the valve or closure element is low so that the valve can be controlled by a spring having a comparatively low spring rate.

A further object of the present invention is to provide a valve assembly in which a multiplicity of valve passages are provided severally closed by valves of low mass and in which the overall area of the valve assembly is utilized efficiently for such valve passages.

Another object of tie invention is to provide such a valve assembly which utilizes standardized and relatively few parts and because of this and its generally simple construction, is relatively inexpensive to manufacture, is unlikely to get out of order or require repair but if servicing is needed, the valve assembly can readily be taken apart for this purpose.

Other objects and advantages of the present invention will be apparent from the following detailed description of a preferred embodiment and the accompanying drawings wherein:

FIG. 1 is a vertical central longitudinal sectional view through a compressor cylinder assembly of the reciprocating double acting piston type and shown as provided with suction and discharge valves severally constructed in accordance with the pinciples of the present invention.

FIG. 2 is a greatly enlarged vertical central sectional view through one of the upper or suction valve assembles shown in FIG. 1 and this view may also be considered as taken along line 22 of FIG. 3.

FIG. 3 is a top plan view, on a reduced scale, of the stop plate member which is the lower member of the assembly shown in FIG. 2, this view being taken on line 3-3 of FIG. 2.

FIG. 4 is a bottom plan view, on a reduced scale, of the seat member which is the upper member of the valve assembly shown in FIG. 2, this view being taken on line 4-4 of FIG. 2.

FIG. 5 is an enlarged fragmentary sectional view through one of the means for holding the aforesaid seat and stop plate members together.

FIG. 6 is an enlarged fragmentary perspective view of one of the blocks forming part of the stop plate member and illustrating the disposition of web elements which extend laterally therefrom and axially thereof to provide guides for the valve which would be associated with this block but is not illustrated in this figure.

FIG. 7 is an enlarged vertical central sectional view through a modified form of valve element or closure.

Referring to FIG. 1, the numeral 10 represents a cylinder member in which a piston 11 is reciprocably arranged. This piston 11 is suitably fast to one end of a piston rod 12 which extends outwardly through an inner end wall member 13 for the cylinder 10. This end wall 13 is suitably secured to the inner end of the cylinder and is also suitably secured to a cylinder support which is connected to the crankcase (not shown) of an engine or other suitable prime mover. The outer end of the cylinder 10 is shown as closed by an end head 14. As is well known, the cylinder is also surrounded by a spaced casing 15 suitably partitioned to provide a suction chest 16 in the upper half of the space between the cylinder 1t and casing 15 and a discharge chest 18 in the lower half. The suction chest 16 is arranged for communication through the fitting 19 with an inlet header (not shown). Similarly, the discharge chest 18 is arranged for communication through the fitting 20 with an outlet header (not shown).

Since the piston 11 is of the double acting type, the cylinder wall 10 adjacent each end is provided with a plurality of valve assembly openings such as shown typically at 21. In a typical compressor cylinder six such valve assembly openings may be provided at each end of the cylinder and arranged at circumferentially spaced intervals, three to accommodate suction valve assemblies in the upper half and the other three to accommodate discharge valve assemblies in the lower half.

The suction valve assembly 22 as shown at the upper left of FIG. 1 has been selected as a representative valve assembly embodying the present invention and will be described in detail.

Referring to FIG. 2, the valve assembly 22 is shown as comprising an upper seat member 23 and a lower stop plate member 24 secured together by fastening means including screw means indicated generally at 25 in FIG. 2.

The lower member 24 is shown as formed with an out wardly extending annular flange 26 adapted to engage a shoulder or step 28 formed in the cylinder 10 above the opening 21 therein. The upper member 23 is also shown as provided with an outwardly extending annular flange 29 which provides a horizontal upwardly facing shoulder 39. Any suitable device may be provided for holding the valve assembly 22 against its seat 28 on the cylinder wall 10. As shown such device comprises one or more yokes or bridges 31 which span the valve assembly diametrically and have feet 32 at their ends to engage the shoulder 30. A hold-down screw 33 suitably carried by the casing 15 can be adjusted to hold the valve assembly 22 against its seat or the screw can be backed off to permit withdrawal of the valve assembly. The hold-down device forms no part of the present invention.

Referring to FIGS. 2 and 4, the upper or seat member 23 is generally a flat plate of disc shape having a flat lower surface 34. A plurality of holes 35 extend vertically through the member 23. Preferably, such through holes 35 are of uniform diameter and are arranged to include a central hole surrounded by at least one annular row or array of spaced holes. In FIG. 4, two annular rows or" holes are shown as arranged around the single central hole.

A valve or closure element 36 is provided for each of the holes 35. These valves 36 are preferably circular, flat sided and of the same diameter as shown in FIG. 2. They are slightly larger in diameter than the holes 35 so that the marginal portion of a valve overlaps the rim of its hole. The valves 36 are arranged to seat against the flat undersurface 34 of the upper member 22 and when so seated, these valves close the respective valve passages 35 in this member. The material of which the valves 36 are made depends upon the nature of the gas and its temperature being handled by the compressor in which the valve assembly is incorporated. Whether the valves .36 are made of metal or a plastic material such as nylon, it is an important feature to keep their mass low. Also, as shown in FIG. 7 the valve 36a instead of being flat may have a downturned annular flange 36' to provide an extended peripheral guide surface and may also have formed into it a downwardly extending annular spring locating bead 36".

Referring to FIGS. 2 and 3, the lower or stop plate member 24 comprises an outer ring or annular portion 38, :a plurality of mutually spaced generally cylindrical blocks 39 arranged severally opposite the holes 35 in the upper or seat member 23. Each of the blocks 39 is shown as tubular and having a horizontal annular end face which is spaced from the opposing lower surface 34 of the upper member 23. One of the valves 36 is arranged for vertical movement in the space thus provided between the opposing surfaces 34 and 49. The surface 40 limits downward movement of the companion one of such valves away from the surface 34.

As best shown in FIGS. 3 and 6, circumferentially spaced web elements 41 extend between adjacent blocks 39 and also between the ring portion 38 and those of the blocks 39 which are arranged in the outer annular row. Some of the web elements 41 extend radially, some extend circumferentially and some extend diagonally. Preferably the blocks 39, web elements 41 and outer ring portion 39 are formed as an integral member as by casting.

As best shown in FIGS. 2 and 6, the various web elements 41 extend axially upwardly beyond the coplanar end faces 40 of the various blocks 39. Such upward extensions are represented at 42 and these collectively have a coplanar upper surface or edge 43 which is adapted to engage the lower surface 34 of the seat member 23. Inasmuch as the axial extensions 42 of the various web elements 41 rise from the end face 40 of the associated block 39, the ends 44 of such extensions are formed as segments of an imaginary cylinder slightly larger in diameter than the circular valve 36 and thus provide guide surfaces for the valve during its vertical movement. When a valve 36 is unseated or out of en gagement with the lower surface 34 of the seat member 123, gas flowing through the hole or passage 35 can flow over the margin of the valve into the arcuate spaces 45 between the raised portions 42 of the web elements 41.

A recess 46 is provided as a counterbore from the stop surface 40 in each tubular block 39, thereby to provide :an upwardly facing annular shoulder 43. A helical compression valve spring 49 is shown as arranged partially in each recess 46 with its lower end resting on the shoulder 48 and its upper end bearing against the lower surface of the companion valve 36. These springs 49 are relatively weak, i.e. they have a relatively low spring rate. Any other suitable type of spring may be used instead of the helical spring 49. i

The upper rims of the holes 35 in the upper member 23 and the lower corners of the end ring portion 38, blocks 39 and web elements 41 of the lower member 24 are suitably rounded, and the mergence of these Web elements .and blocks are provided with fillets, to reduce turbulence in the gas as it flows vertically downwardly through the valve assembly as illustrated in FIG. 2.

It will be seen that as the piston 11 reciprocates in the cylinder 10 the portion of the cylinder on the trailing side of this piston will tend to create a suction thereby producing a pressure differential between the interior of the cylinder 10 and the suction chest 16 with the predominant pressure in the suction chest. The pressure diiferential thus established across the various valves 36 will cause these valves 36 to open or move downwardly against the urging of their respective return springs 49. Since the valves 36 are of low mass, the valve return springs 49 can be relatively weak so that the force required to open the various valves 36 individually is comparatively low.

It will be seen that when the piston 11 moves in the opposite direction so that the pressure differential tends to reverse with the predominant pressure being on the spring side of the valves 36 the various springs 49 will return their respective valves 36 to their seats against the lower surface 34 of the upper or seat member 23.

To permit ready assembly and disassembly of the various components of the valve assembly, the same is shown as provided with a pair of fastening means 25 arranged at diametrically opposite positions. Referring to FIG. 5, the upper or seat member 23 is provided with a vertical through hole 50 the upper end portion of which is smaller in diameter and internally threaded as indicated at 51. The lower or stop plate member 24 is provided with an integral boss 52 internally formed with a vertical through hole 53 which alines with the corresponding hole 50 in the upper member 23. The lower portion of the hole 53 in the lower member 24 is shown as being of smaller diameter than the upper portion and is internally threaded as indicated at 54. The fastener is a special form of machine screw including an enlarged head 55, a shank 56 preferably with a reduced central portion and a slightly enlarged externally threaded end portion 58. The shank portion 56 is small enough in diameter to pass through either of the internally threaded portions 51 or 54 and the externally threaded end portion 58 of the fastener is adapted to be screwed into either of the internally threaded end portions 51 and 54, depending upon which end of the combined holes 50, 53 receives the inserted end of the screw. Preferably the head 55 is on the side of the valve assembly when mounted on the cylinder 10 which is remote from the interior of the cylinder. The arrangement described permits the fastener or screw 25 to be inserted either from the top of the assembly of two members 23, 24 as shown in FIG. 5 or from the bottom, in case the same members were used, as the case for discharge valves.

The bosses 52 for accommodating the screws or fasteners 25 are preferably formed as an integral part of the stop plate member 24.

From the foregoing, it will be seen that the present invention provides a two-part cage for a multiplicity of low mass valves and companion low rate springs. The preferred embodiment shown and described is illustrative and not limitative of the present invention the scope of which is measured by the appended claims.

What is claimed is:

1. In a valve construction, the combination comprising a disc-shaped seat member having a flat surface on one side and provided with a plurality of through holes including a central hole surrounded by at least one annular row of holes, a circular valve for each of said holes and of larger diameter so as to close the same when engaging said surface, an integral member including an outer ring, a plurality of mutually spaced generally cylindrical blocks arranged severally opposite said holes in said seat member, each of said blocks having an end face spaced from said surface for limiting movement of the companion one of said valves away from said surface, and circumferentially spaced web elements extending between adjacent pairs of said blocks and also between said ring and those of said blocks opposite said annular row of holes, said web elements having edges axially oifset from said end face and engaging said surface and also having ends which rise from said end faces to provide guides for said valves, each of said blocks having a recess from its said end face, and a spring seated in said recess and bearing against the corresponding one of said valves for urging the same toward said surface.

2. In a valve construction, the combination comprising a seat member provided with a plurality of passages, a valve for each of said passages and closing the same when engaging said seat member, astop plate member for limiting the lift of said valves, spring means urging said valves toward a closed position, and means for securing said members together and including alined through holes provided in said members, the outer portion of each such hole in said members being internally threaded, and a fastener insertable into said alined holes from either end and including a head, shank and externally threaded end having a larger maximum trans verse dimension than said shank, said head bearing against the outside of one of said members, said shank extending through said hole in said one of said members and being unattached thereto and said externally threaded end being received in said interally threaded hole portion in the other of said members.

References Cited in the file of this patent UNITED STATES PATENTS 1,268,720 Jackson June 4, 1918 1,483,153 Baker Feb. 12, 1924 2,727,531 Blackford Dec. 20, 1955 2,804,086 Johnston Aug. 27, 1957 2,891,571 Sparks June 23, 1959

Claims (1)

1. 2. IN A VALVE CONSTRUCTION, THE COMBINATION COMPRISING A SEAT MEMBER PROVIDED WITH A PLURALITY OF PASSAGES, A VALVE FOR EACH OF SAID PASSAGES AND CLOSING THE SAME WHEN ENGAGING SAID SEAT MEMBER, A STOP PLATE MEMBER FOR LIMITING THE LIFT OF SAID VALVES, SPRING MEANS URGING SAID VALVES TOWARD A CLOSED POSITION, AND MEANS FOR SECURING SAID MEMBERS TOGETHER AND INCLUDING ALINED THROUGH HOLES PROVIDED IN SAID MEMBERS, THE OUTER PORTION OF EACH SUCH HOLE IN SAID MEMBERS BEING INTERNALLY THREADED, AND A FASTENER INSERTABLE INTO SAID ALINED HOLES FROM EITHER END AND INCLUDING A HEAD, SHANK AND EXTERNALLY THREADED END HAVING A LARGER MAXIMUM TRANSVERSE DIMENSION THAN SAID SHANK, SAID HEAD BEARING AGAINST THE OUTSIDE OF ONE OF SAID MEMBERS, SAID SHANK EXTENDING THROUGH SAID HOLE IN SAID ONE OF SAID MEMBERS AND BEING UNATTACHED THERETO AND SAID EXTERNALLY THREADED END BEING RECEIVED IN SAID INTERALLY THREADED HOLE PORTION IN THE OTHER OF SAID MEMBERS.

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