AU629566B2 - Check valves and plate therefor - Google Patents

Description

To: THE COMMISSIONER OF PATENTS (amember of the firm of DAVIES COLLISON foi, and on behalf of the Applicant).

Davies Collison, Melbourne and Canberra.

yr COMMONWEALTH OF A S 5 6A6 PATENT ACT 1952 COMPLETE SPECIFICATION

(ORIGINAL)

FOR OFFICE USE CLASS INT. CLASS Application Number: Lodged: Complete Specification Lodged: Accepted: Published: #09 0 0@ 0 4 a a a4 Priority: Related Art-: *000 0~ *0 S 00 S C 06 #560 00 S0 4 NAME OF APPLICANT: ADDRESS OF APPLICANT: NAME(S) OF INVENTOR(S) STOCKhti VALVE AUSTRALIA PTY. LTD.

322 Settlement Road, Thomnastown 3074 Victoria

AUSTRALIA

GARY ALLAN HOCKING ADDRESS FOR SERVICE: DAVIES COLLISON, Patent Attorneys 1 Little Collins Street, Melbourne, 3000.

COMPLETE SPECIFICATION FOR THE INVENTION ENTITLED: 4 ,aOa-ECI V2'~i 1" Cve-c< -VC\Vj-eS 'X~e V~ The following statement is a full description of this invention, including the best method of performing it known to us

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Insert place and date of signature.

Signature of declarant(s) (no attestation required) Note, Initial all alterations, Declared at'.*s thij.-' ~d DAVIES COLLISON, MELBOURNE and CANBERRA.

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-2a *9 sq 0 0 etatat a a it 84 aa I a at 0* a. a a a a CHECK VALVES AND PLATE THEREFOR This invention relates to check valves and valve plates therefor.

20 In a known form of check valve, the valve comprises a body having a bore therethrough. A pair of semi-circular valve plates are mounted on a hinge pin which extends across the bore. In the closed position of the valve, the plates are generally co-planar and transverse to the bore through the body. In this position the peripheries of the plates engage a valve seat to form a seal. In the open position, the plates rotate away from the valve seat and a stop pin is normally being provided to limit the extent of rotathn of the plates.

Normally the plates are cast in stainless steel or bronze and need to be machined prior to assembly. It will be appreciated that the known plates are relatively heavy and are laborious to produce. These factors increase the costs of production of the plates.

920630,gcpdat.00 _141012.c,2 Insert place and date of signature, Signature of declarant(s) (no aftestation required) Note: Initial all alterations.

Declareda thisa U aW day o-98s DAVIES COLLISON. MELBOURNE and CANBERRA.

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-3- An object of the present invention is to provide a novel form of plate which subsf -ntiplly reduces these problems.

According to the present invention there is provided a plate for a check valve, comprising: i) a generally semi-circular body; ii) a valve face formed on one side of the body for engaging, in use, a valve seat of the valve; iii) at least one hinge lug for mounting the plate on a hinge pin; and LO iv) a peripheral flange extending from said body on the opposite side to said valve seat characterized in that the body, lug and flange are integrally plastically deformed from sheet metal.

It is further preferred that the plate is formed by deformation of stainless steel a1 a 'fr, a 1a sheet.

The plates can be made in a range of diameters from 40 to 2500mm. It is further preferred that the thidkness of the stainless steel sheet material is at least The ,nvention also provides a check valve which includes the valve plates defined above.

In known forms of check valves, a valve body has a central bore across which a hinge pin is mounted. A pair of valve plates are hingedly connected to the hinge pin. In the closed position, the plates are generally co-planar and extend transversely across the bore. A stop pin is also jXl 1

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920630,gcpdat.002,41012c,3

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~YC~ ilx i; ;r 0 *444 4 C I 4 C It C C C connected across the bore and serves to limit rotational movement of the plates when in their open position.

The known arrangement has a number of disadvantages.

A first disadvantage is the labour cost involved in mounting of the ends of the pins in the valve body. The valve body must be drilled and tapped so that plugs can be inserted to hold the ends of the pins in place. Also pin stabilisers are sometimes fitted between the ends of the pins and the plugs. These manufacturing steps are quite laborious and therefore contribute significantly to the cost of the valve.

Another problem with the known arrangement is that turbulence in the fluid flowing through the valve bore can cause rotation of the pins. This increases the rate of wear and corrosion of the valve body adjacent to the pins, especially where the valve bodies are made from cast iron. Failures can occur because of hole enlargement owing to this rotation.

A further object of the present invention is to provide a clip for supporting the ends of the pins, the provision of the clip at least partially overcoming the problems noted above.

*Accordi-ng--t-o--.-seCondaspet d of-theinvention there is provided a c' ee O se in a check valve, said c -u ing first and second recess r i ii-n ua. o£ h in- a-n =f pp- nandi projections of the clise ive recesses The invention will now be further described with reference to the accompanying drawings, in which: Figure 1 is an axial view, partly in section, of a check valve of the invention; Figure 2 is a cross-sectional view along the line 2-2; Figure 3 is a fragmentary sectional view along the line 3-3; 0 0 Figure 4 is a side view of a clip of the valve; Figure 5 is an edge view of the clip; Figure 6 is an opposite side view of the clip; Figure 7 is a side view of another clip;of Figure 8 is an edge view of the other clip; o Figure 9 is an opposite side view of the other clip; o Figure 10 is a side view of a valve plate of the invention; Figure 11 is an edge view of the valve *I plate; and Figure 12 is a sectional view along the line 12-12.

The valve diagrammatically shown in Figures 1 and 2 comprises a valve body 2 having a generally hollow cylindrical shape. The body has end flanges 4 and 6, sidewall 8, valve seat 10 and centre rib 12.

i 6 The end flanges could be omitted and a diametrical rib provided on the body. The valve has first and second generally semi-circular plates 14 and 16 pivotally connected on a hinge pin 18 which extends generally parallel to the rib 12. The valve includes a stop pin 20 which extends across the valve body parallel to the hinge pin 18. The stop pin 20 serves to limit the degree of opening of the valve plates 14 and 16, as illustrated the top half of Figure 1 which shows the plate 14 in its fully opened position. The valve includes a spring 22 having end legs 27 and 29 "00 which bias the plates 14 and 16 into sealing contact with the valve seat 10 and the rib 12 (the spring is omitted in Figure 2 for clarity of illustration).

Elastomeric seals 11 are provided on the seat t I The pins 18 and 20 are carried by a pair of clips 24 which are illustrated in Figures 4, 5 and 6. The clips 24 are preferably formed from sheet stainless steel such as 420 or duplex and 06 o subsequently hardened or worked and tempered, if 6 09 necessary, to have the resilience of a spring. As best seen in Figure 5, the clip has a front face 26 9944 9* 4 and rear face 28 connected by a curved portion The front face 26 includes a lower bore 32 and an upper bore 34. The rear face 28 has a central inturned tab 36 which engages the front face 26 and serves to maintain the gap between the faces 26 and 28. The rear face 28 includes a pair of slots 38 extending generally longitudinally and defining outwardly projecting resilient fingers As best seen from Figures 1 and 3, the clips 24 received within recesses 42 formed on opposite sides of the valve body. The recesses 42 have a "'My iNX width which generally corresponds to the width of the clips 24. However, as seen in Figure 2, the recesses include rebates 44 which receive the resilient fingers 40 and thus hold the clips 24 in place. The depth of the recesses 42 is such that the front faces 26 of the clips are located within the bore of the valve, as seen in Figure 1.

The clip 25 illustrated in Figures 7, 8 and 9 is generally similar to that shown in Figures 4, and 6 and functions in the same way. In this (d arrangement however the tab 36 is omitted but the lower corners 27 and 29 of the face 26 are deflected ri inwardly to touch the adjacent face 28 and thereby maintain the gap therebetween.

The valve is assembled by first forming a sub-assembly which comprises the pins 20 and 22 with the plates 14 and 16 and spring 22 mounted thereon.

The sub-assembly includes the clips located on the 4 ends of the pins. The sub-assembly is then pressed into the bore of the valve so that the clips 24 enter the recesses 42 and when the clips 24 are fully seated within the recesses, the resilient fingers will engage the rebates 44 to hold the sub-assembly firmly in place in the valve body. In this position, r' the valve plates 14 and 16 engage the seals 11 bonded to the valve seat The valve can be made in various sizes say from 40 to 2500mm and the clips can be made in corresponding sizes.

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Q t' 8 Figures 10, 11 and 12 illustrate in more detail the novel shape of the valve plates 14 and 16. The plates are identical and therefore only one need be described. The plate 14 is formed from pressed stainless steel sheet material such as SAF 304 stainless steel. It has a generally semi-circular face 50 formed with a central domed depression 52 for stiffening the plate, the front face forming a flat surface which forms a seal against the elastomeric seal 11. The curved edge of the plate is formed with a rearwardly directed strengthening flange 54. The transverse edge of the plate is formed with hinge lugs 56 and 58 which in use permit the plate to be mounted on the hinge pin 18. At the centre of the transverse edge is an abutment formation 60 which includes a leg 62 which t is generally parallel to the face 50 of the plate and an inturned leg 64 which abuts the recess 52 and therefore assists in keeping the required shape of the abutment projection. The transverse edge 444 includes flanges 66 extending between the lugs 56 and 58 and the formation 60 for strengthening purposes.

Figures 1 and 2 show the plates 14 and 16 mounted on the hinge pin 18. The configuration is such that the faces 50 of the plates engage the seals 11 when the mounting clips 24 are correctly seated in the recesses 42. The spacing and lengths of the lugs 56 and 58 and formations 60 is chosen to extend substantially the full length of the pin 18 so as to avoid unwanted axial movement of the plates along the pin. Washers 61 can be provided between adjacent pairs of lugs, as seen in Figure 1. When the valve is opened, the plates 14 and 16 rotate inwardly, 9 inward rotation being stopped on engagement of the abutment face 62 on the stop pin The plates formed as described above are very much cheaper to produce than known plates which are normally cast and then machined. In addition to being much cheaper to produce, the plates have less weight and should improve the efficiency of the valve by lowering pressure losses and reduce closing time.

Many modifications will be apparent to those skilled in the art without departing from the spirit and scope of the invention.

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Claims (10)

1. A plate for a check valve, comprising: i) a generally semi-circular body; ii) a valve face formed on one side of the body for engaging, in use, a valve seat of the valve; iii) at least one hinge lug for mounting the plate on a hinge pin; and iv) a peripheral flange extending from said body on the opposite side to said valve seat characterized in that the body, lug and flange are integrally plastically deformed from sheet metal.

2. A plate as claimed in claim 1 wherein the plate includes a stop formation which, in use, comes into engagement with a stop pin for limiting rotation of the plate.

3. A plate as claimed in claim 2 wherein the stop formation extends from the Iplate on the same side as said flange, and is located adjacent t0a the centre of the straight side of the semi-ckcular plate. 1 ,20 It'

4. A plate as claimed in claim 3 wherein there are two of said hinge lugs one located adjacent one end of the straight side of the semi-circular plate and the other being located on said straight side intermediate of the stop formation and the other end of said straight side. A plate as claimed in any one of claims 1 to 4 including a domed depression extending in the same direction as said flange and bounded by said valve face, said domed depression being integrally plastically deformed in said body. 920630,gcpda.002,41012.c,10 U^ j I i I:

11- 6. A plate as described in any preceding claim wherein the sheet metal comprises stainless steel, the thickness of which is at least 7. A check valve comprising: a valve body having valve seats therein; a hinge pin extending across said body; and a pair of plates as described in any preceding claim, the hinge lugs of which are rotatably mounted on said hinge pin to enable rotation of said plates from closed positions in which the valve faces engage respective valve seats to open positions in which the valve faces are spaced from the respective valve seats. 8. A check valve comprising a valve body, a hinge pin having an axis, a pair of valve plates as defined in any one of claims 1 to 6 mounted on the hinge pin, a pair of pin support members carried by the valve body wherein said support members prevent contact of the ends of the pin with the valve body and each includes at least one recess to receive an end of said hinge pin and integral resilient projections for resiliently engaging and interlocking with the valve body, said projections being resiliently deflectable in a plane transverse to said axis. C C 4 5 C S 9. A check valve comprising: a valve body having valve seats therein; a hinge pin extending across said body; a pair of valve plates as defined in any one of claims 1 to 6 rotatably mounted on said hinge pin to enable rotation of said plates from closed positions in which the valve faces engage respective valve seats to open positions in which the valve faces are spaced from the respective valve seats; and a pair of clips, each said clip including at least one recess to receive the end of said hinge pin and being characterized by integral resilient projections for resiliently engaging and interlocking with the valve body to hold the hinge pin in the valve body. 920630,gcdlat.00A,41012.cII

12- A check valve comprising: a valve body having valve seats therein; a hinge pin extending across said body; and a pair of valve plates as defined in any one of claims 1 to 6 rotatably mounted on said hinge pin to enable rotation of said plates from closed positions in which the valve faces engage respective valve seats to open positions in which the valve faces are spaced from the respective valve seats said valve body including recesses for resiliently receiving respective clips, the clips including recesses for supporting of the ends of the hinge pin and means preventing contact of the end of the hinge pin with the valve body, said means being integral with the clip. 11. A check valve as claimed in claim 10 wherein the valve includes a stop pin which is, in use, engaged by the plates in their open positions and wherein the clips 15 include recesses for supporting the ends of the stop pin and means for preventing ii,; contact of the end of the stop pin with the valve body. t t t C I 12. A check valve as claimed in claim 9 wherein the projections of the clips are resilien' deflectable in planes transverse to the axis of said hinge pin. It

13. A check valve as claimed in claim 11 wherein each clip includes a clip body having first and second recesses which receive the hinge and stop pins, said clip body including portions adjacent to the recesses for engaging, in use, the ends of pins and thereby preventing the ends of the pins contacting the valve body and wherein said clip body has a plate-like front face, a plate-like rear face and a connecting portion interconnecting said faces, the faces being spaced and parallel, said first and second recesses being located in said front face and wherein said portions adjacent to the recesses comprises said rear face. ',9206304g"dat.002,41012.c,12 f. :i 13- ce.\c4 va\,le-

14. A elipas claimed in claim 13 wherein resilient fingers of each clip project laterally from the rear face in the plane thereof.

15. A plate for a check valve substantially as hereinbefore described with reference to the accompanying drawings.

16. A check valve substantially as hereinbefore described with reference to the accompanying drawings. I i i rcri r r I r t r r c c rr rrt c r t c DATED this 30th day of June, 1992 STOCKHAM VALVE AUSTRALIA PTY. LTD. 20 By its Patent Attorneys DAVIES COLLISON CAVE 920630,gcpdat.002,41012.c,13 I