EP0040930A1 - Soupape avec siège constitué de matière plastique renforcée - Google Patents

Soupape avec siège constitué de matière plastique renforcée Download PDF

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Publication number
EP0040930A1
EP0040930A1 EP81302137A EP81302137A EP0040930A1 EP 0040930 A1 EP0040930 A1 EP 0040930A1 EP 81302137 A EP81302137 A EP 81302137A EP 81302137 A EP81302137 A EP 81302137A EP 0040930 A1 EP0040930 A1 EP 0040930A1
Authority
EP
European Patent Office
Prior art keywords
valve
seating
outer body
arms
centre
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP81302137A
Other languages
German (de)
English (en)
Other versions
EP0040930B1 (fr
Inventor
Harold Humphrey Frederick
Harold Humphrey Brock
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
IIC Mechanical Products Ltd
Original Assignee
IIC Mechanical Products Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by IIC Mechanical Products Ltd filed Critical IIC Mechanical Products Ltd
Priority to AT81302137T priority Critical patent/ATE4739T1/de
Publication of EP0040930A1 publication Critical patent/EP0040930A1/fr
Application granted granted Critical
Publication of EP0040930B1 publication Critical patent/EP0040930B1/fr
Expired legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B39/00—Component parts, details, or accessories, of pumps or pumping systems specially adapted for elastic fluids, not otherwise provided for in, or of interest apart from, groups F04B25/00 - F04B37/00
    • F04B39/10—Adaptations or arrangements of distribution members
    • F04B39/102—Adaptations or arrangements of distribution members the members being disc valves
    • F04B39/1033—Adaptations or arrangements of distribution members the members being disc valves annular disc valves

Definitions

  • the invention relates to self-actuating valves such as are used in compressors, and in particular, to such valves made of synthetic plastic materials.
  • the invention also relates to a method of manufacturing such valves, and other articles made in accordance with such methods.
  • Self acting valves are used in compressors, and in other applications. Such valves simply comprise a body and a valve closure member which is spring actuated into a closed position, and is adapted to lift off its seat on a predetermined pressure differential across the valve.
  • valves particularly when used in compressors, are subjected to continuous duty operation twenty-four hours a day in many cases and are subject to heavy wear.
  • the stresses imposed on such valves during operation are very considerable. As a result they break down frequently, and the replacement and maintenance of such valves is a continuous problem.
  • Valves of this type have always been made of metal such as steel, and are usually machined out in complex shapes requiring many hours of costly machining. Consequently, they represent a substantial cost in the operation of, for example, compressors.
  • valve bodies in an entirely different way, with machine time reduced to a minimum.
  • manufacture such valve bodies out of a material which, in the event of the valve body becoming shattered, e.g. by impact of entrained matter such as liquids and solids moving with the gases at high velocity, does not break up the pistons and score the cylinder walls of the compressor.
  • valve closure members were annular bodies of plastic material.
  • the valve bodies were made of steel.
  • breakage of the closure members did not cause such serious consequences.
  • Pieces of plastic entering the cylinders would not score the cylinder walls or damage the piston in the same way as pieces of steel.
  • the valve bodies were still made of steel, and in the event that a portion of the valve body was broken, then the same consequences would follow as described above.
  • this form of valve incorporated certain inherent problems of its own.
  • the coefficient of expansion of the plastic material is three times greater than that of steel.
  • valve body portions of the valve of some material other than steel, and to fabricate the valve body portions and the valve closures out of material having the same or substantially the same coefficients of expansion, so as to avoid the problems described above, while yet incorporating sufficient inherent stress resistance as to be capable of withstanding the extreme stresses developed in normal operation.
  • a valve structure of the type comprising a seating member defining at least one valve opening therethrough, and a closure member
  • said seating member comprising, an outer body portion, a center core portion, a plurality of arms extending from said center core portion to said outer body portion, seating means formed on said outer body portion and said centre core portion for reception of said closure means thereon, said outer body portion and centre core portion and said arms all being formed integrally in a single homogeneous structure of synethetic plastic materials having reinforcing fibres extending from said centre core through said radial arms into said outer body, said reinforcing fibres being embedded in and completely surrounded by a mouldable plastic resin material.
  • the invention also provides a method of manufacturing a valve structure comprising the steps of forming at least two panels of mouldable plastic resin material, in an outline corresponding to the plan view of the valve structure, forming at least two groups of unidirectional reinforcing fibres, and arranging said at least two groups between said panels, to form a stack, with said groups of fibres intersecting one another in a central area of said valve structure, placing said stack in a mould, closing the mould and applying heat and pressure thereto, thereby to mould and form said stack into a single homogeneous structure, with said fibres completely enveloped and embedded in said plastic resin material.
  • the invention also comprises the fabrication of other articles of manufacture in accordance with such method, and also comprises other such articles of manufacture.
  • further groups of such reinforcing fibres may be arranged around the periphery of such article.
  • valves of the type suitable for use in compressors. It will be understood that such valves are used in pairs, one valve functioning as an inlet and the other as an exhaust. They are usually placed in position in a compressor block or head (not shown) and are held in position by any suitable clamping means (not shown) which may be releasable, so that the valves may be removed and replaced for servicing.
  • the valve will be seen to comprise a seating portion 10, and a spring bearing portion 12, being of generally cylindrical shape in plan.
  • the seating portion 10 is provided with a plurality of gas passageways 14, and the spring bearing portion is provided with a plurality of gas ports 16.
  • the seating portion and spring bearing portion enclose between them two valve closure rings 18 and 20 which are of a generally annular shape in plan, and which are dimensioned and adapted to close off the passageways 14.
  • the rings 18 and 20 are movable, and are held in position by means of springs 22, located in the spring bearing portion 12.
  • valve seating portion 10 will be connected with the incoming supply of gas, and the spring bearing portion 12 will be connected with the compressor.
  • both the seating portion 10 and spring bearing portion 12 and rings 18 and 20 are made of synthetic plastic material, in a manner to be described below, so that the only metal components are in fact the springs 22.
  • the present embodiment of the invention is seen to comprise a valve seating portion 10 having a central core 24 of generally cylindrical shape, and intermediate seating ring 26, and an outer ring 28.
  • Outer ring 28 is provided with a stepped shoulder 30 for reasons to be described below.
  • the core 24, ring 26 and ring 28 are all united together in a single integral structure by means of radial arm members 32 which extend from core 24 to intermediate ring 26 and then on to outer ring 28. In the embodiment shown, four such arms 32 are illustrated. It will, however, be appreciated that this is not limiting, and other numbers of such arms 32 may be provided.
  • intermediate ring 26 is shown. It will of course be appreciated that more such intermediate rings may be provided, concentric with one another and concentric with core 24 if a larger valve structure is desired. On the other hand in a much smaller valve structure it may be desirable to dispense with the intermediate ring 26 altogether, in which case the radial arms 32 would simply extend from the centre core 24 to the outer ring 28.
  • the radial arms 32 when viewed in section are of a reduced height in relation to the height of the centre core 24,intermediate ring 26 and outer ring 28. In this way, the core 24 and rings 26 and 28 define between them continuous annular spaces or grooves indicated as 34 and 36, and uninterrupted by the radial arms 32.
  • the gas passageways 14 which are defined between the radial arms 32, communicate with the continuous annular grooves 34 and 36, for free flow of gases therethrough.
  • Angled valve seating surfaces 38 are formed on the core 24 and rings 26 and 28 as shown for reception of the valve closure rings 18 and 20 described above.
  • the valve closures 18 and 20 are generally triangular in cross-section, having two angled upstream surfaces 40 forming a V-shape, and having a generally flat planar downstream surface 42, for engagement by springs 22.
  • the two upstream surfaces 40 rest on the valve seating surfaces 38, and preferably meet at an angle between about 80 and 100 degrees.
  • a substantial portion of the closure rings 18 and 20 thus extends downwardly into the annular grooves 34 and 36.
  • the radial arms 32 being of reduced height, leave a substantial free space all'around such annular grooves. In this way when the valve is open the two surfaces 40 of rings 18 and 20 smoothly divide the gases flowing through grooves 34 and 36 into two streams, with a minimum of turbulence, thus maximizing the efficiency of the valve.
  • the spring bearing portion 12 of the valve is constructed on a generally similar principle to the seating portion 10.
  • the seating portion 10 comprises a centre core portion 44, four radial arms 46 extending therefrom, and intermediate ring 48 supported by the radial arms 46, and an outer ring 50.
  • the core 44,arms 46 and intermediate ring 48 are all of the same thickness in section, and that the outer ring 50 is of a greater thickness, defining a downwardly extending annular junction portion 52, shaped and dimensioned to fit snugly in around shoulder 30 of outer ring 28 on seating portion 10.
  • gas ports 16 in spring bearing portion 12 are defined between the centre core portion 44, arms 46, intermediate ring 48, and outer ring 50, and in fact are located around three essentially circular concentric paths. Such concentric paths are generally speaking off-set with respect to the annular passageways 34 and 36 of seating portion 10, so that gases passing upwardly therethrough and around the rings 18 and 20 may then pass freely through ports 16 with a minimum of obstruction.
  • a central support boss 54 is provided on core 44, in a generally cruciform shape in plan, which is adapted to engage the upper surface of centre core 24 and four further generally rectangular support bosses 56 are provided on the radial arms 46 which are adapted to engage the intermediate ring 26 at various points therearound, registering with the radial arms 32.
  • a plurality of spring receiving recesses 58 are formed in the core 44, being located around a generally annular path corresponding to the diameter of the inner valve closure ring 18.
  • the centre core 44 is made somewhat oversized in order that it may receive such recesses 58, and it will be noted that the recesses 58 are off-set to one side of the axis of the radial arms 46, for reasons to be described below.
  • spring mounting blocks 60 are supported between intermediate ring 48 and outer ring 50, and further such blocks 62 are supported on one side of the radial arms 46, adjacent to the junction of intermediate ring 48 therewith. All of such blocks 60 and 62 are located around a generally annular path corresponding to the diameter of the outer valve closure ring 20, and are provided with spring receiving recesses 64 therein. Each of the recesses 58 and 64 is provided with a small gas vent opening. This permits gases to blow off any particles which may lodge in the spring recesses.
  • the springs 22 are of a generally tapering frusto-conical shape, with the larger diameter end seating within the respective recesses 58 or 64, and in this way the remainder of the spring is held out of contact with the surfaces of the recess, thereby substantially prolonging its life.
  • the seating portion 10 and spring bearing portion 12 are assembled together with the springs 22 and rings 18 and 20 in position as shown. Preferably, they are permanently bonded or otherwise fastened together, both around the surfaces of the junction portion 52 and shoulder 30, and also at the interfaces between core 24 and central bosses 54 and intermediate ring 26 and bosses 56.
  • the entire structure of the seating portions 10 and spring bearing portions 12 are made of plastic resin materials in a manner to be described below.
  • the plastic materials from which the valves according to the invention are manufactured are preferably those known as Sheet Moulding Compound, known in the trade as "SMC".
  • SMC materials comprise reinforcing glass fibres, in a plastic resin base.
  • the plastic resin base is compounded with suitable catalysts, such that at room temperatures it is relatively stable and has an extended shelf life, and is essentially solid so that it may be readily handled, and cut. However, when subjected to heat, it becomes mouldable, and the catalysts are activated so that the material rapidly sets hard.
  • Such SMC material is thus particularly suitable for moulding under heat and pressure in a closed mould. Articles formed in this way are found to have high strength, in some cases equalling that of steel. At the same time, fragments of such material when shattered, are substantially less abrasive then fragments of steel, and thus if such fragments should enter into the cylinders of a compressor, they will do little or no damage.
  • valve body 10 and spring bearing portion 12 of the valve according to the invention are preferably formed of a composite of materials, essentially shown schematically in Figure 7.
  • each such portion of the complete valve will comprise upper and lower panel portions 70 and 72 of SMC material, which may be cut into a circular disc shape as shown, or may be cut into any other desired shape, for example, the shape of a cross, as may be most suitable for fitting in the particular mould.
  • unidirectional reinforcing fibres 74 Sandwiched between the two panel portions 70 and 72 will be groups of unidirectional reinforcing fibres 74.
  • These unidirectional reinforcing fibres may be further filaments of glass fibre material. However, preferably they will be of fibres of carbon, graphite, boron, aramid or even metal, or other reinforcing fibres having a strength greater than that of glass fibres.
  • Each of the groups of fibres 74 will be preferably coated with liquid plastic resin material, incorporating a suitable catalyst, just prior to moulding.
  • additional chunks 76 of SMC material are preferably arranged in the "sandwich" between panel portions 70 and 72.
  • the composite of such materials is then placed in a suitable mould (see Figure 9) and subjected to heat and pressure thereby first of all rendering the SMC material mouldable and flowable, and subsequently setting the plastic resin materials.
  • moulding which may take place in a 15 minute cycle, for example, depending upon the composition of the SMC material, the article is then removed from the mould and cleaned up and any "flashing" is removed.
  • Continuous lengths of unidirectional reinforcing fibres 82 are prepared by passing the same through rollers R, applying plastic resin material thereto, and subsequently cutting the same by means of knife K into bundles 74.
  • the lowermost panel portion 72 is then placed in the bottom of a mould M of a suitable shape.
  • Mould M is provided with suitable heating means, in this place illustrated schematically as electrical heating elements B although heating may be provided by other means such as liquids, or mould M may be placed in an oven.
  • the reinforcing fibres 74 having been arranged preferably in a suitable jig G (not shown) into the form of a cross, or any other suitable arrangement, are then placed in mould M and the chunks 76 of SMC material are then placed in position, more-or-less as shown in Figure 9.
  • the upper panel portion 70 is then placed in position after which the upper half of the mould is then closed.
  • the mould is then subjected to heat and pressure causing the SMC material to become sufficiently plastic that it flows into the shape of the mould, after which the plastic resin material is cured and set.
  • reinforcing fibres 74 In some cases, where making valves for lower pressure compressors, or where making valves of a smaller size, it may be possible to omit the inclusion of the reinforcing fibres 74. It will, however, be appreciated that where these reinforcing fibres 74 are incorporated, they will be completely embedded and covered by the SMC material, and will in fact form the radial arms 32, of the valve seating portion 10, or the radial arms 46 of the spring seating portion 12 respectively.
  • the spring recesses 58 are all formed in areas which are off-set with respect to the arms, in the spring seating portion 12, in the manner described above, so that the recesses 58 and 64 do not cut into such reinforcing fibres 74, which would reduce their effectiveness.
  • a circular article which may be considered as a valve, but may be a variety of different articles, such as a gear wheel or the like, may be provided having a core 90, a plurality of radial arms 92, and an outer rim 94. As shown in Figure 11, openings are defined between arms 92. It will be appreciated that the structure of Figure 11 is essentially schematic, and a variety of different shapes of such an article may be designed as required.
  • unidirectional fibres 74 extend through the core 90 and along the radial arms 92. Additional unidirectional fibres 74a are arranged around the outer ring 94. The unidirectional fibres 74 and 74a are embedded within moulded SMC material in the manner described above, to form a single homogeneous integral article.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Check Valves (AREA)
  • Lift Valve (AREA)
  • Valve Housings (AREA)
  • Laminated Bodies (AREA)
  • Casting Or Compression Moulding Of Plastics Or The Like (AREA)
  • Pens And Brushes (AREA)
  • Temperature-Responsive Valves (AREA)
EP81302137A 1980-05-23 1981-05-14 Soupape avec siège constitué de matière plastique renforcée Expired EP0040930B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT81302137T ATE4739T1 (de) 1980-05-23 1981-05-14 Ventil mit aus armiertem kunststoff bestehenden ventilsitz.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CA000352635A CA1155034A (fr) 1980-05-23 1980-05-23 Robinet en plastique renforce
CA352635 1980-05-23

Publications (2)

Publication Number Publication Date
EP0040930A1 true EP0040930A1 (fr) 1981-12-02
EP0040930B1 EP0040930B1 (fr) 1983-09-21

Family

ID=4117025

Family Applications (1)

Application Number Title Priority Date Filing Date
EP81302137A Expired EP0040930B1 (fr) 1980-05-23 1981-05-14 Soupape avec siège constitué de matière plastique renforcée

Country Status (7)

Country Link
EP (1) EP0040930B1 (fr)
JP (1) JPS5718880A (fr)
AT (1) ATE4739T1 (fr)
AU (1) AU7060881A (fr)
CA (1) CA1155034A (fr)
DE (1) DE3160941D1 (fr)
ZA (1) ZA813181B (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1310712A2 (fr) 2001-11-07 2003-05-14 HOERBIGER KOMPRESSORTECHNIK SERVICES GmbH Eléments d'étanchéité pour soupapes de compresseur
EP1310713A2 (fr) 2001-11-07 2003-05-14 HOERBIGER KOMPRESSORTECHNIK SERVICES GmbH Eléments d'étanchéité pour soupape de compresseur

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU632212B2 (en) * 1991-04-08 1992-12-17 Garlock Pty Ltd Improved multiple-ring compressor valve

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE809501C (de) * 1949-07-21 1951-07-30 Miag Vertriebs Gmbh Ventilplatte
GB674386A (en) * 1950-03-31 1952-06-25 Compressor Accessories Ltd Improvements in or relating to valves for fluids
FR1058907A (fr) * 1952-03-13 1954-03-19 D Applic Mecaniques Soc Ind Perfectionnements aux obturateurs ou soupapes à fonctionnement automatique pour lescompresseurs, surpresseurs, machines soufflantes et machines analogues
GB778884A (en) * 1954-05-31 1957-07-10 Anciens Ets Brisson Improvements in and relating to valves
AT275004B (de) * 1967-03-14 1969-10-10 Halle Maschf Veb Ventilplatte
US3536094A (en) * 1968-03-12 1970-10-27 Flavious E Manley Jr Compressor valve

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE809501C (de) * 1949-07-21 1951-07-30 Miag Vertriebs Gmbh Ventilplatte
GB674386A (en) * 1950-03-31 1952-06-25 Compressor Accessories Ltd Improvements in or relating to valves for fluids
FR1058907A (fr) * 1952-03-13 1954-03-19 D Applic Mecaniques Soc Ind Perfectionnements aux obturateurs ou soupapes à fonctionnement automatique pour lescompresseurs, surpresseurs, machines soufflantes et machines analogues
GB778884A (en) * 1954-05-31 1957-07-10 Anciens Ets Brisson Improvements in and relating to valves
AT275004B (de) * 1967-03-14 1969-10-10 Halle Maschf Veb Ventilplatte
US3536094A (en) * 1968-03-12 1970-10-27 Flavious E Manley Jr Compressor valve

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1310712A2 (fr) 2001-11-07 2003-05-14 HOERBIGER KOMPRESSORTECHNIK SERVICES GmbH Eléments d'étanchéité pour soupapes de compresseur
EP1310713A2 (fr) 2001-11-07 2003-05-14 HOERBIGER KOMPRESSORTECHNIK SERVICES GmbH Eléments d'étanchéité pour soupape de compresseur

Also Published As

Publication number Publication date
DE3160941D1 (en) 1983-10-27
CA1155034A (fr) 1983-10-11
EP0040930B1 (fr) 1983-09-21
ZA813181B (en) 1982-06-30
AU7060881A (en) 1981-11-26
ATE4739T1 (de) 1983-10-15
JPS5718880A (en) 1982-01-30

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