Background of the Invention

This invention relates to flow control, and, more parti cularly, to the control of fluid flow making use of pressure diffe entials. in many situations it is necessary to con-trol the flow fluids, such as liquids and gases. A common device for that purpo is kno-wn as a check valve. It functions fa the deflection of an elastomeric element towards a valve seat in order to prevent flow and away from -the seat to permit flow. one such device is the check valve disclosed in U.S. Pa

3,839.710 which issued to Julien H. 3rost on June 17, 1975. It co ^• ains an elastomeric disc that is de lected towards and away from concave sea-ting surface that surrounds an inlet. The disc is deli erately made smaller than -the seating surface. This is to permit reverse flow around the edges of -the disc. unfortunately, -the use of a concave seating surface wi- a floatable disc. i.e. one that is smaller than the seating surface causes a number of di iculties. In the first place a valve wi-h a concave seating surface is susceptible to malfunction because inevi -table particles of debris -that become trapped be-tween the disc and its concave seat. Once debris becomes trapped it tends to remain on the seat during subsequent operations of the -valve. In addition since -the disc is smaller than its seat it tends to move about with ^• the result -that different portions of the surface become stressed during subsequent operations. Furthermore, there is an undesirable tendency for a portion of the disc to be drawn into the associated inlet during closure operation of the -valve.

Other known valves for controlling flow are those illus¬ trated by -the following patents:

Patent No. Issued Inventor

797,739 8/1905 Meer

1,412,473 4/1922 Lane

1,506,012 8/1924 Lewis 2,547,377 4/1951 Juhasz

3,342,866 4/1966 Sanz

3,664,371 5/1972 Schneider

Still other known valves for controlling flow are those illustrated by the following additional patents: Patent No. Issued Inventor

3,807,445 _ 4/1974 ^* . McPhee

3,954,121 ^* 5/1976 Kardns

Accordingly, it is an object of the invention to facili¬ tate the con_rol of fluid flow. A related object is to facilitate the control of fluid flow using.differential-pressures-.

A further object of the invention is to overcome the difficul-ties associated with prior check valves. A related object is to avoid the difficulties associated with a single disc check valves. Still ano^ther object of the inven-fcio ^' is to avoid -the difficulties associated with "floatable" disc. A related object is to avoid -the difficulties associated wi-th discs that are smaller than their associated seats. Another related object is to avoid the random wear pattern associated with "floatable" discs. ye another object of the inven-ttion is to reduce disc distortion in check -valves. A related object is to reduce -the ten¬ dency for a disc -to be drawn into a flow channel and produce disc distortion.

A yet further object of the invention is to facilitate the seating action of a valve disc and render the valve substantially self purging of debris, such as dirt and dust, that could otherwise ^" interfere witn the seating operation.

Summary of the Invention In accomplishing the foregoing and related objects, the invention provides for the exercise of low control using a resii-

iant and flexible disc which is restricted to movement along -the longitudinal axis of a control channel. This avoids the disadvan¬ tages of variable positionable discs, while retaining their advan¬ tages. In accordance with one aspect of the invention the disc is sy-rametrically positioned with respect to -the control channel to assure uniform performance of -the disc during opening and closure operations.

In accordance wi-th ano-ther aspect of the invention, -the disc has a ring seat with rounded, convex shoulders that facilitate seating during initial preloading of the disc, and facilitate the self-purging of debris from the seat.

In accordance wi-h still ano-ther aspect of the invention, the entrance of -the flow channel is a base depression surrounded by -the ring seat. This helps assure that the disc is securely seated when the valve is fully closed.

In accordance with yet another aspect of -the invention, the base depression of the ring seat includes radial channels that limit the tendency for the disc to be drawn into -the flow channel. According to a further aspect of the invention, -the con¬ trol channel includes peripheral grooves for the flow of fluid durin the open condi-tion of the valve.

According to a still further aspect of the invention, -the disc is prestressed by a member with auxiliary flow channels for accommodating the reverse flow of fluid through the -valve. The latter channels are desirably symmetrically, laterally and radially Dositioned with resoect to a main flow channel.

Descriotion of the Drawings

O-ther aspects of the invention will become apparent after considering several illus-trative embodiments taken in conjunction with -the drawings in which: FIGURE 1 is a perspective view of a con-trol valve in accor¬ dance with the inventionr

FIGURE 2 is a fragmentary cross-sectional view of -the contro valve of FIGURE 1;

FIGURE 3 is an end view of a constituent member of the control valve showing s-tructural channels for reverse operation and tήe avoidance of control disc distortion;

FIGURE 4 is an end.view of a complementary constituent mem¬ ber- of the -valve showing an abu-ment structure for preloading the control disc and facilitating reverse operation; FIGURE 5 is a fragmentary view of the structure of FIGURE 2 showing the control disc in its closed, posi-tion to prevent fluid from flowing through -the -valve;

FIGURE 6 is a fragmentary view similar to that of FIGURE 5 showing the control disc in i-ts open position to permit the passage of fluid through -the valve.

FIGURE 7 is a persepctive view of an alternative control valve in accordance wi-h the invention;

FIGURE 8A is a cross-sectional view of -the valve of FIGURE 7 with the constituent parts of the valve separa _t ed to show their inter-relationship with greater clarity; and

FIGURE 8B is a cross-sectional view of an alternative valve which is an improvement over the valve of FIGURE 3A, with its constituent parts separated and including an intermediate. segmented annular rib for enhanced flexure control.

Detailed Description With reference to the drawings, illustrative control valves 10, 100, and 100', all in accordance with the invention, are shown in respective FIGURES 1, 3A and 3B. 5 The control valve 10 of FIGURE 1 is formed by complementa body members 20 and 30 with flow channels 21 and 31 that are controlled by a flexible, elastomeric con-trol disk 40, as sho-wn in the cross-sectional view of FIGURE 2.

The control valve 100 of FIGURE 3A is also formed by 10 complementary body members, which are respectively designated 200 and 300. The latter contain respective flow channels 210 and 310 that are controlled by a flexible, elastomeric control disk 400.

The control valve 100' of FIGURE 8B is similar to that 15 of FIGURE 8A. It has complementary body members 200 ^' and 300', wi-fch respective flow channels 210 and 310* . The same elasto¬ meric control disk 400 that is used for the valve of FIGURE 3A is also used in the valve of FIGURE SB.

Considering first the details of the control valve 10 20 of FIGURE 1, its control disk 40 is positioned within the flow channel 21, which serves as a control channel, in the body membe 20. By con-trast with the prior art, -the disk 40 has substantial the same circumferential diameter as the channel 21. It is to be noted that the channel 21 in -the body member 20 includes 25 two concentric portions, a narrowly constricted portion which extends away from the mating body member 30, and diverges into a wider portion towards the body member 30. The disk 40 has substantially the same circumferential diameter as the channel 21 at its wider portion, as clearly demonstrated in FIGURE 2. 30

As a result there is substantially no lateral movement of the disc 40 with respect to the channel 21.

As further indicated in FIGURE 2, -the disc 40 is seated on the flange surface of a ring seat 22. The ring 22 has a hollow inter

5 ior with a convex shoulder 23 to promote secure sealing in accordance with the invention.

In addition, -the ring seat 22 surrounds a base depression 24 containing the inlet of the channel 21. The base depression 24 further includes a set of radial channels 25 (more particularly shown

10 in FIGURE 3} that insure -that the disc 40 will not be pulled into -the inlet of the channel 21, and thus produce undesired distortion and distension of the disc 40. Longitudinal channels 26 are included at the periphery of the control channel 21 to facilita-te reverse flow through -the valve 10.

15 The disc 40 is prebiased to provide initial sea-ting contact against: the ring 22 by prongs 32 of the member 30. These prongs 32, which are illus-trated in end -view in FIGURE 4, are s earated by pass¬ ageways 33 which extend to the outlet channel 31.

It is to be noted that the joinder of the complementary por

20 tions 20 and 30 of the body structure 10 can be made in any convenien way along an interface 11. For the particular embodiment of FIGURE 2 the interface 11 includes a sealing ring 13, but it will be understoo -that such a ring is illustrative only and -that a wide -variety of seal ing techniques may be used.

25 As sho-wn in FIGURE 5, when a differential pressure exits between the channels 21 and 31, with the greater pressure at the channel 31, for excample produced by a vacuum applied to -the channel 21 in -the direction of the arrow A, the disc 40 is drawn away from th prongs 32 into closer con-tact wi-th the shoulder 23 of -the ring seat 2

30 bringing about -the desired closure of the valve 10 and isolation of

the channels 21 and 31. Since the sealing surface of the ring 22 i in.the form of a convex shoulder 23 that extends circumferentially about the base depression 24, the desired seal is achieved without any adverse affect because of the inadvertent pressence of dirt or debris on the sealing edge 23. This is by contrast with, for examp the sealing surfaces of prior art devices in which the presence of dirt and debris will interfere with the desired closure. In such a case the initial application of sealing pressure does not dislodge the debris, but instead traps it between the disc and the sealing sα face. In the case of the present invention, however, any debris on

-the ring seat tends to be moved away by -the appreciable convex curva ture 23 of the ring 22, coupled with the interior void formed by the base depression 24.

It is to be noted that because of -the radial channels 25 i the base depression 24, the disc 40 cannot be drawn into toe inlet channel 21. This avoids -the distension of the con-trol disc frequent found in other devices, caused by having -the disc sucked into a flow channel.

The reverse operation of -the valve 10 is illustrated in FIGURE 6. When the differential pressure that pulls the disc 40 against the shoulder 23 is removed and the flow is reversed, -the dis 40 again is positioned against the prongs 32. Flow can now take pla in the direction indicated by -the arrow B be-tween the ring seat 22 a the edge of the disc 40 through -the auxiliary longitudinal channels 26.. Because of -the channels 26, it is not necessary to reduce -the diameter of the disc 40 below -that of the control channel 21 in orde to permit the desired reverse operation.

An alternative control valve 100 in accordance with the invention is illustrated in FIGURE 7. As in the case of -the contro valve 10 of FIGURE 1, the valve 100 of FIGURE 7 is formed by comple mentary body members 200 and 300 with flow channels 210 and 310 tha are controlled by a flexible, elastomeric control disk 400, illus¬ trated in the cross-sectional view of FIGURE 8.

The control disk 400 is positioned wi-fchin the control channel 210 of the body member 200. As in the case of the disk 40 of FIGURE 2, the disk 400 of FIGURE 8 has substantially the same circum erential diameter as the channel 210. In addition the shoulders 201 of the member 200 are provided with a radius in order to prevent the disk 400 from becoming trapped between -the parts 200 and 300 during assembly of the valve. It has been discovered that because of the prebiasing of the disk provided by the. rongs. . 320 of -the member 300 there is otherwise a tendency for the disk

400 to be shifted out of the channel 210 during -the assembly proce¬ dure. ^" The radiusing of the shoulders 2U1 helps to assure that the disk 400 will enter and seat properly in the channel 210. In additi the channel 210 contains a seat 221 of a ring 220 which has substan- tially the same diameter as the disk 400 in its relaxed, unbiased state. The seat 221 extends slightly below the shoulders 201. Between adjoining ones of the shoulders 201 slots 202 are provided which function in a manner similar to that of the longitudinal channels 26 shown in FIGURE 3. However, instead of being semicircul the slots 202 of FIGURE 8 are quadrilateral wi-th side walls 202s that lie along -the raditis from -the central axis A. In addition each slot 202 has a rear wall 202r that is an arc of a cylinder that is concentric with the axis A. This configuration of the slots has been found desirable to facilitate construction of the member 220, as well as promote the operation of the valve. Moreover, it has been found desirable to uniformly distribute the slots along the wall of -the valve wi-fch the slots 202 having the same arc lengrh

as -the shoulders 201. In the illustrative embodiment of FIGURE

8, eight slots are provided and eight shovl ders.

Also indicated in FIGURE S is the extension of the seat 221 below edges of the slots 202. This disposition of the slots relative to the seat has been fotαnd to further promote the operatio of the valve. Additionally, the ring 220 has a base 222 which has a diameter that makes the area of -the base 222 greater than one- fourth the area of -the seat 221. In an illustrative embodiment of the invention the ratio between the diameter of the base 222 and the seat 221 was approximately 3 to 4.

.The entry from the base 222 into the channel 210 at the coupling portion 205 of the member 200 includes a rounded edge 223. This limits the tendency for the disk 400 to be sucked into the channel 210 at the coupling 205. As can be seen for the member 300 of FIGURE 3, the bias¬ ing prongs 320 are provided with outwardly sloping buttresses 321 in order to give -them suitable streng-th. In an illustrative embodi ment of the invention the angle of the buttress with respect to the linear inner wall 322 was approximately 15°. A similar angle of depression was found appropriate for the inwardly tapered surfac 323 extending from -the tip 324 of each prong 320. A channel 330 is provided between adjoining ones of the wedged-shaped prongs 320. The base of each channel 330 has a rounded edge 331 where the chann 310 meets the prong channel 330. A sheif 340 that engages the uppe surfaces of the shoulders 201 when the parts 200 and 300 are assem¬ bled includes a ridge 341 of triangular cross-section that is included in order to promote -the sealing of the parts 200 and 300 together by sonic bonding.

While various aspects of the invention have been set forth by the drawings and specification, it is to be understood that the foregoing detailed description is for illustration only and that various changes in parts, as well as the substitution of

1 Still another control valve 100' in accordance with the invention is illustrated in FIGURE 8B. As in the case of the control valve 100 of FIGURE 8A, the valve 100* of FIGURE 8B is formed by complementary body members. One of the body members

5 200 is identical with -the corresponding body member 200 of FIGURE 8A. The other body member 300* is a modification of the body member 300 of FIGURE SA. In addition, the body member 300* includes a flow channel 310' and a segmented annular ring 350'. The ring 350" includes individual segments 351', 352' , 353',

10 etc.

. The segmented ring 350' functions in connection wi-th the flexible, elastomeric control disk 400 that is positioned at the diverging opening of the control channel 210 in the body member 200._ - ..

15 As in the case of FIGURE 8A, biasing prongs 320 engage the disk 400 when the parts 200 and 300' are brought together. In addition, -the segmented ring 350' is present to prevent the flexible disk 400 from overflexing upwardly when the valve 100* is operated in its open position with the flow into the channel

20 210 and -then ou-twardly into the channel 310* . The presence of the individual segments 351' etc. tends to prevent the disk 400 from inadvertently hanging on to any portion of the body member 300' and assure that the disk 400 will return to its closed position when flow from the channel 210 into the channel

25 310 ^■ is removed. It is to be noted that -the individual segments 351' etc. have complementary, sloping buttresses which diverge from the apex point facing the disk 400 towards the base at the interior of the member 300'.

While various aspects of the invention have been set

30 forth by -the drawings and specification, it is to be understood that the foregoing detailed description is for illus-tration only and that various changes in parts as well as the substitution of

equivalent constituents for those shown and described may be made without departing from the spirit and scope of the invention as set forth in the aooended claims.