Pinch valve subassemblies and arrangements

Abstract

A pinch element subassembly (10) for a pinch valve includes a cartridge member (20) and a flexible pinch element (40). The cartridge member includes a through passage extending axially from a first end face (21) of the cartridge member to a second end face (22) of the cartridge member, a first end bearing portion (23) extending radially outward of a central portion (26) of the cartridge member to define a first circumferential sealing portion (33), and a second end bearing portion (24) extending radially outward of the central portion to define a second circumferential sealing portion (34). The flexible pinch element has a tubular portion (45) extending axially through the cartridge member through passage, a first flanged end portion (41) extending over and sealing against the cartridge member first end face, and a second flanged end portion (42) extending over and sealing against the cartridge member second end face.

Description

PINCH VALVE SUBASSEMBLIES AND ARRANGEMENTSCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to and all benefit of U.S. Provisional Patent Application Serial No. 63 / 701,710, filed on October 1, 2024 and entitled PINCH VALVE SUBASSEMBLY, and U.S. Provisional Patent Application Serial No. 63 / 863,674, filed on August 14, 2025 and entitled PINCH VALVE SUBASSEMBLIES AND ARRANGEMENTS, the entire disclosures of each of which are incorporated by reference herein.TECHNICAL FIELD

[0002] This disclosure relates to pinch valve subassemblies for use in fluid control systems and assemblies, such as, for example, pump assemblies for dry particulate material.BACKGROUND

[0003] Pinch valves include elastomeric tubular elements that can be compressed or squeezed from an open position permitting fluid flow to a pinched closed position preventing fluid flow. Pinch valves are used in a variety of applications, including, for example, applications in which it is desirable to minimize or eliminate fluid contamination of the system components or cavities surrounding the valve. One such exemplary system is a dense phase powder pump, in which a dose of fluidized powder material is drawn through an opened fluid receiving pinch valve into a chamber of the pump, and then delivered through an opened fluid delivering pinch valve to a dispensing device, such as a spray gun. An exemplary dense phase powder pump is shown and described in co-owned U.S. Patent No. 7,997,878 (the “’878 Patent”), the entire disclosure of which is incorporated herein by reference.SUMMARY

[0004] According to an exemplary embodiment of the present disclosure, a pinch element subassembly includes a cartridge member defining a through passage extending axially from a first end face of the cartridge member to a second end face of the cartridge member, a first end bearing portion extending radially outward of a central portion of the cartridge member to define a first circumferential sealing portion, and a second end bearing portion extending radially outward of the central portion to define a second circumferential sealing portion, and a flexible pinch element having a tubular portion extending axially through the cartridgemember through passage, a first flanged end portion extending over and sealing against the cartridge member first end face, and a second flanged end portion extending over and sealing against the cartridge member second end face.

[0005] According to another exemplary embodiment of the present disclosure, a valve assembly includes a valve housing block defining an axially extending through bore extending from a first end of the valve housing to a second end of the valve housing, a first body block secured to the first end of the valve housing block and including a first passage aligned with the valve housing block through bore, a second body block secured to the second end of the valve housing and including a second passage aligned with the valve housing block through bore, and a pinch element subassembly installed in the valve housing block through bore. The pinch element subassembly includes a cartridge member and a flexible pinch element. The cartridge member defines a through passage extending axially from a first end face of the cartridge member to a second end face of the cartridge member, a first end bearing portion forming a first circumferential seal between the cartridge member and the valve housing block through bore, and a second end bearing portion forming a second circumferential seal between the cartridge member and the valve housing block through bore. The flexible pinch element includes a tubular portion extending axially through the cartridge member through passage, a first flanged end portion axially compressed between the cartridge member first end face and the first body block, and a second flanged end portion axially compressed between the cartridge member second end face and the second body block.

[0006] According to another exemplary embodiment of the present disclosure, a valve assembly includes a valve body block defining a central passage extending axially from a first end of the valve body block to a second end of the valve body block, with the central passage including a first end counterbore portion at the first end of the valve body block, a first end connector assembled to the first end of the valve body block and providing a first end connection for the central passage, and a first end pinch element subassembly installed in the first end counterbore portion and including a cartridge member defining a through passage and a flexible pinch element having a tubular portion extending axially through the cartridge member through passage, a first flanged end portion extending over and sealing against a cartridge member first end face, and a second flanged end portion extending over and sealing against a cartridge member second end face. The first flanged end portion is axially compressed between the cartridge member first end face and a shoulder surface of thefirst end counterbore portion, and the second flanged end portion is axially compressed between the cartridge member second end face and the first end connector.

[0007] According to another exemplary embodiment of the present disclosure, a pump assembly includes a venturi unit and pump body having an inlet port at a first end, an outlet port at a second end, a central passage extending from the inlet port to the outlet port, a purge port intersecting with a mid-portion of the central passage, a flow port intersecting with an outlet portion of the central passage, and an atomizing port intersecting with the outlet portion of the central passage. A first shutoff valve is installed in the central passage between the purge port and the inlet port, and a second shutoff valve is installed in the central passage between the purge port and the outlet port. The venturi unit includes a pump coupling assembled with the outlet port, an injector retained in an upstream counterbore of the pump coupling, a throat holder retained in a downstream counterbore of the pump coupling, and a throat element retained in the throat holder. When flow air is supplied to the flow port, the flow air passes through one or more upstream openings in the pump coupling and into a duct in the injector to exit through an injector nozzle directing the flow air through the throat element. When atomizing air is supplied to the atomizing port, the atomizing air passes through one or more downstream openings in the pump coupling and through one or more openings in the throat holder to pass along an annular gap between the throat holder and the throat element to exit a downstream end of the throat holder.BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Further advantages and benefits will become apparent to those skilled in the art after considering the following description and appended claims in conjunction with the accompanying drawings, in which:

[0009] FIG. 1 A is a perspective view of an exemplary pump assembly;

[0010] FIG. IB is an exploded perspective of the pump assembly of FIG. 1 A;

[0011] FIG. 1C is another exploded perspective of the pump assembly of FIG. 1A;

[0012] FIG. ID is a side view of the pump assembly of FIG. 1A;

[0013] FIG. IE is a cross-sectional side view of the pump assembly of FIG. 1 A;

[0014] FIG. IF is another side view of the pump assembly of FIG. 1A;

[0015] FIG. 1G is another cross-sectional side view of the pump assembly of FIG. 1 A;

[0016] FIG. 2A is a perspective view of the valve body of the pump assembly of FIG. 1 A;

[0017] FIG. 2B is a cross-sectional side view of the valve body of FIG. 2A;

[0018] FIG. 3A is a perspective view of an exemplary pinch element subassembly, in accordance with an exemplary embodiment of the present disclosure;

[0019] FIG. 3B is a side cross-sectional view of the pinch element subassembly of FIG. 3 A;

[0020] FIG. 3C is a perspective cross-sectional view of the pinch element subassembly of FIG. 3A;

[0021] FIG. 3D is a top cross-sectional view of the pinch element subassembly of FIG. 3 A;

[0022] FIG. 4A is a perspective view of an exemplary pinch element subassembly, in accordance with another exemplary embodiment of the present disclosure;

[0023] FIG. 4B is a side cross-sectional view of the pinch element subassembly of FIG. 4A;

[0024] FIG. 4C is a perspective cross-sectional view of the pinch element subassembly of FIG. 4A;

[0025] FIG. 4D is a top cross-sectional view of the pinch element subassembly of FIG. 4A;

[0026] FIG. 5 is a cross-sectional view of an exemplary valve assembly including a removable pinch element subassembly, in accordance with an exemplary embodiment of the present disclosure;

[0027] FIG. 6 is a cross-sectional view of an exemplary pump assembly, in accordance with an exemplary embodiment of the present disclosure;

[0028] FIG. 6A is a partial enlarged cross-sectional view of the pump assembly of FIG. 6;

[0029] FIG. 7A is a front perspective view of an exemplary pump assembly, in accordance with another exemplary embodiment of the present disclosure;

[0030] FIG. 7B is a rear perspective view of the pump assembly of FIG. 7 A; and

[0031] FIG. 7C is a front cross-sectional view of the pump assembly of FIG. 7A.DETAILED DESCRIPTION

[0032] This Detailed Description merely describes exemplary embodiments and is not intended to limit the scope of the claims in any way. Indeed, the invention as claimed is broader than and unlimited by the described embodiments, and the terms used in the claims have their full ordinary meaning.

[0033] While various inventive aspects, concepts and features of the inventions may be described and illustrated herein as embodied in combination in the exemplary embodiments, these various aspects, concepts and features may be used in many alternative embodiments, either individually or in various combinations and sub-combinations thereof. Unless expressly excluded herein all such combinations and sub-combinations are intended to be within the scope of the present inventions. Still further, while various alternativeembodiments as to the various aspects, concepts and features of the inventions— such as alternative materials, structures, configurations, methods, circuits, devices and components, software, hardware, control logic, alternatives as to form, fit and function, and so on— may be described herein, such descriptions are not intended to be a complete or exhaustive list of available alternative embodiments, whether presently known or later developed. Those skilled in the art may readily adopt one or more of the inventive aspects, concepts or features into additional embodiments and uses within the scope of the present inventions even if such embodiments are not expressly disclosed herein. Additionally, even though some features, concepts or aspects of the inventions may be described herein as being a preferred arrangement or method, such description is not intended to suggest that such feature is required or necessary unless expressly so stated. Still further, exemplary or representative values and ranges may be included to assist in understanding the present disclosure, however, such values and ranges are not to be construed in a limiting sense and are intended to be critical values or ranges only if so expressly stated. Parameters identified as “approximate” or “about” a specified value are intended to include both the specified value, values within 5% of the specified value, and values within 10% of the specified value, unless expressly stated otherwise. Further, it is to be understood that the drawings accompanying the present disclosure may, but need not, be to scale, and therefore may be understood as teaching various ratios and proportions evident in the drawings. Moreover, while various aspects, features and concepts may be expressly identified herein as being inventive or forming part of an invention, such identification is not intended to be exclusive, but rather there may be inventive aspects, concepts and features that are fully described herein without being expressly identified as such or as part of a specific invention, the inventions instead being set forth in the appended claims. Descriptions of exemplary methods or processes are not limited to inclusion of all steps as being required in all cases, nor is the order that the steps are presented to be construed as required or necessary unless expressly so stated.

[0034] In an exemplary dense phase pump assembly disclosed in the above incorporated ’878 Patent, as reproduced in FIGS. 1A - 1G and 2 A - 2B herein, the pump 402 includes a pump manifold body 414 and a valve body 416. The manifold body 414 houses a pair of pump chambers along with a number of air passages, and the valve body 416 houses a plurality of pinch valve elements or pinch elements 480, 481. The pinch elements respond to air pressure signals that are communicated into the valve body 416 from the manifold body 414.

[0035] The upper portion 402a of the pump is adapted for purge air arrangements 418a, 418b, and the lower portion 402b of the pump is adapted for a powder inlet hose connector 420 anda powder outlet hose connector 422. A powder feed hose may be connected to the inlet connector 420 to supply a flow of powder from a supply such as a feed hopper. A powder supply hose may be used to connect the outlet 422 to a spray applicator whether it be a manual or automatic spray gun positioned at a spray booth. The powder supplied to the pump 402 may, but not necessarily must, be fluidized.

[0036] Powder flow into and out of the pump 402 thus occurs on a single end 402b of the pump. This allows a purge function 418 to be provided at the opposite end 402a of the pump thus providing an easier purging operation.

[0037] In order to produce a steady, consistent and adjustable flow of powder from the pump, two or more pump chambers are provided. When two pump chambers are used, they are preferably operated out of phase so that as one chamber is receiving powder from the inlet the other is supplying powder to the outlet. In this way, powder flows substantially continuously from the pump. With a single chamber this would not be the case because there is a gap in the powder flow from each individual pump chamber due to the need to first fill the pump chamber with powder. When more than two chambers are used, their timing can be adjusted as needed. In any case it is preferred though not required that all pump chambers communicate with a single inlet and a single outlet.

[0038] Since each pump chamber communicates with the same pump inlet and outlet in the exemplary embodiment, additional modular units are used to provide branched powder flow paths in the form of branching body blocks or Y blocks. A first Y-block 424 is interconnected between the manifold body 414 and the valve body 416, and a second Y-block 426 forms the inlet / outlet end of the pump and is connected to the side of the valve body 416 that is opposite the first Y-block 424. The first Y-block 424 provides a two branch powder flow path away from each powder chamber. One branch from each chamber communicates with the pump inlet 420 through the valve body 416 and the other branch from each chamber communicates with the pump outlet 422 through the valve body 416. The second Y-block 426 is used to combine the common powder flow paths from the valve body 416 to the inlet 420 and outlet 422 of the pump. In this manner, each pump chamber communicates with the pump inlet through a control valve and with the pump outlet through another control valve. Thus, in the exemplary embodiment, there are four control valves in the valve body that control flow of powder into and out of the pump chambers.

[0039] The manifold 414 includes a body 432 having first and second bores therethrough 434, 436 respectively. Each of the bores receives a generally cylindrical gas permeable filter member 438, 440, described in greater detail in the above incorporated ‘878 Patent. Thefilter members 438, 440 each define an interior volume (438c, 440c) that serves as a powder pump chamber so that there are two pump powder chambers provided in this embodiment. A portion of the bores 434, 436 are adapted to receive the purge air arrangements 418a and 418b. When a pressure chamber has negative pressure applied to it, powder is drawn up into the powder pump chamber and when positive pressure is applied to the pressure chamber the powder in the powder pump chamber is forced out.

[0040] The manifold body 432 includes a series of six inlet orifices 442. These orifices 442 are used to input pneumatic energy or signals into the pump. Four of the orifices 442a, c, d and f are in fluid communication via respective air passages 444 with a respective pressure chamber 446 in the valve block 416 and thus are used to provide valve actuation air. The remaining two orifices, 442b and 442e are respectively in fluid communication with the bores 434, 436 via air passages 444b and 444e. These orifices 442b and 442e are thus used to provide positive and negative pressure to the pump pressure chambers in the manifold body.

[0041] An air supply manifold (described in greater detail in the above incorporated ‘878 Patent) includes a corresponding set of orifices that align with the pump orifices 442 and are in fluid communication therewith when the supply manifold is mounted on the pump manifold 414. In this manner the supply manifold can supply all required pump air for the valves and pump chambers through a simple planar interface. Because of the volume, pressure and velocity desired for purge air, preferably separate purge air connections are used between the supply manifold and the pump manifold.

[0042] In operation, powder enters through a common inlet 420 and branches via paths 502a or 502b in the lower Y-block module 498b (retained in housing 492) to the two inlet or suction pinch valve elements 480. Each of the inlet pinch valve elements 480 is connected to a respective one of the powder pump chambers 434, 436 via a respective one branch 452, 454 of a respective path through the first or upper Y-block 424. Each of the other branches 452, 454 of the upper Y-block 424 receive powder from a respective pump chamber, with the powder flowing through the first Y-block 424 to the two outlet or delivery pinch valve elements 481. Each of the outlet pinch valve elements 481 is also connected to a respective one of the branches 502a, 502b in the lower Y-block module 498a wherein the powder from both pump chambers is recombined to the single outlet 422.

[0043] When any of the pinch valve elements is to be closed, the supply manifold 404 issues a pressure increase at the respective orifice 442 in the manifold body 414. The increased air pressure flows through the respective air passage 442, 444 in the manifold body 414, downthrough the respective air passage 456 in the first Y-block 424 and into the respective air passage 486 in the valve body 416 to the appropriate pressure chamber 446.

[0044] With reference to FIGS. 2A and 2B, the valve body 416 includes four through bores 446a, 446b, 446c and 446d that function as pressure chambers for a corresponding number of pinch valves. The upper surface 466 of the valve body includes two recessed regions 468 and 470 each of which includes two ports, each port being formed by one end of a respective bore 446. In this embodiment, the first recessed portion 468 includes orifices 472 and 474 which are formed by their respective bores 446b and 446a respectively. Likewise, the second recessed portion 470 includes orifices 476 and 478 which are formed by their respective bores 446d and 446c respectively. Corresponding orifices are formed on the opposite side face 479 of the valve body 416.

[0045] Each of the pressure chambers 446a-d retains either an inlet pinch valve element 480 or an outlet pinch valve 481. Each pinch valve element 480, 481 is a fairly soft flexible member made of a suitable material, such as for example, natural rubber, latex or silicone. Each valve element 480, 481 includes a central generally cylindrical body 482 and two flanged ends 484 of a wider diameter than the central body 482. The flanged ends function as seals and are compressed about the bores 446a-d when the valve body 416 is sandwiched between the first Y-block 424 and the second Y-block 426. In this manner, each pinch valve defines a flow path for powder through the valve body 416 to a respective one of the branches 452, 454 in the first Y-block 424. Therefore, one pair of pinch valves (a suction valve and a delivery valve) communicates with one of the pump chambers 440 in the manifold body while the other pair of pinch valves communicates with the other pump chamber 438. There are two pinch valves per chamber because one pinch valve controls the flow of powder into the pump chamber (suction) and the other pinch valve controls the flow of powder out of the pump chamber (delivery). The outer diameter of each pinch valve central body portion 482 is less than the bore diameter of its respect pressure chamber 446. This leaves an annular space surrounding each pinch valve that functions as the pressure chamber for that valve.

[0046] The valve body 416 includes air passages 486a-d that communicate respectively with the four pressure chamber bores 446a-d. as illustrated in FIG. 2B. These air passages 486a-d include vertical extensions 488a-d (as viewed in FIG. 2B). These four air passage extensions 488a-d respectively are in fluid communication with the vertical portions of the four air passages 444d, f, a, c in the manifold 414 and the vertical passages 456d, f, a, c in the upper Y-block 424. Seals 490 are provided for air tight connections.

[0047] In this manner, each of the pressure chambers 446 in the valve body 416 is in fluid communication with a respective one of the air orifices 442 in the manifold body 414, all through internal passages through the manifold body, the first Y-block and the valve body. When positive air pressure is received into the pump manifold 414, the corresponding pinch element 480, 481 is closed by the force of the air pressure acting against the outer flexible surface of the flexible pinch element. The pinch elements open due to their own resilience and elasticity when external air pressure in the pressure chamber is removed. This true pneumatic actuation avoids any mechanical actuation or other control member being used to open and close the pinch valves. Each of the four pinch valves 480, 481 is preferably separately controlled for the pump 402.

[0048] The valve body recessed portions 468, 470 may be sized and dimensioned to retain the flanged ends 484 of the pinch elements 480, 481. During installation of the pinch element 480, 481, the leading flange end 484 must be radially squeezed or compressed into the corresponding pressure chamber bore 446a-d in the valve body 416, and pushed through the pressure chamber bores for resilient expansion into seating engagement with the corresponding valve body recessed portion 468, 470. When the valve body 416 is assembled between the upper and lower Y-blocks or body blocks 424, 426, the pinch element flange ends 484 are axially compressed between the valve body recessed portion 468, 470 and the Y-blocks to provide a leak tight seal. To remove the pinch element 480, 481 from the valve body 416, the trailing flange end 484 must be squeezed or compressed to pull the flange end through the corresponding pressure chamber bore 446a-d. This squeezing and pushing / pulling of the pinch element may be a time consuming and labor intensive procedure.

[0049] Similar pinch valve body block arrangements may be used in other assemblies, including, for example, venturi style pump assemblies, such as, for example, the venturi VT pump arrangement used in the Spectrum VT Feed Center powder coating system, manufactured by Nordson Corporation.

[0050] According to an exemplary aspect of the present disclosure, a valve assembly, for example, a dense phase or venturi powder pump valve assembly, may be provided with one or more pinch element subassemblies configured to facilitate installation into and / or removal from one or more corresponding through bores of a valve housing block. In some embodiments, a pinch element subassembly includes a cartridge member configured to be slidably installed in and / or removed from a valve housing block through bore, with a flexible pinch element having a tubular portion disposed in a through passage of the cartridgemember, and first and second flanged end portions extending over first and second end faces of the cartridge member.

[0051] FIGS. 3A, 3B, and 3C illustrate an exemplary pinch element subassembly 10 including a cartridge member 20 and a flexible pinch element 40. The cartridge member 20 includes a through passage 25 extending axially from a first end face 21 to a second end face 22. First and second end bearing portions 23, 24 of the cartridge member 20 extends radially outward of a central portion 26 to provide first and second circumferential sealing portions 33, 34. In the illustrated embodiment, the first and second circumferential sealing portion 33, 34 include gasket seals (e.g., O-rings) 31, 32 retained in annular grooves 37, 38 in the bearing portions 23, 24.

[0052] The pinch element 40 includes a tubular portion 45 extending axially through the through passage 25 of the cartridge member 20, and first and second flanged end portions 41, 42 extending radially outward from the tubular portion, over and sealing against the first and second end faces 21, 22 of the cartridge member.

[0053] As shown, the end faces 21, 22 of the cartridge member 20 may be defined by annular ribs 21a, 22a extending axially outward from the bearing portions 23, 24. The annular ribs 21a, 22a may be rounded to provide an annular bead surface. The radial width of the annular ribs 21a, 22a may be smaller than the radial width of the pinch element flanged end portions 41, 42, such that the flanged end portions extend radially beyond the cartridge member end faces 21, 22.

[0054] The cartridge member 20 may be configured to allow pressurized fluid (e.g., air, nitrogen) to constrict and close the tubular portion 45 of the pinch element 40. As shown, the central portion 26 of the cartridge member 20 may be substantially cylindrical and may include one or more laterally extending cross ports or holes 27 allowing pressurized fluid introduced into the valve body through bore (shown in FIG. 5 and described in greater detail below). To allow for uniform pressurization around the periphery of the pinch element tubular portion 45, the cartridge member 20 may include first and second inner lip portions 35, 36 extending radially inward from the central portion 26 of the cartridge member 20 for engagement with the tubular portion of the pinch element, to define an annular gap between the central portion of the cartridge member and the tubular portion of the pinch element. As shown, the first and second lip portions 35, 36 may be at least partially axially aligned with the first and second end bearing portions 23, 24, and may extend axially from the bearing portions to define the first and second end faces 21, 22.

[0055] The cartridge member 20 may be sized to provide interference fit engagement between the flanged end portions 41, 42 of the pinch element 40 and the end faces 21, 22 of the cartridge member, for example, to provide a continuous circumferential seal between the cartridge member and the flanged end portions. Additionally or alternatively, the flanged end portions 41, 42 of the pinch element may be axially compressed between the valve housing block and the end body blocks, as described in greater detail below.

[0056] The cartridge member 20 may be a single piece or monolithic component, in which the pinch element 40 is installed by radially squeezing or compressing the leading flange end into the cartridge member through passage 25 and pushing the flange end past the through passage for resilient expansion into seating engagement against the cartridge member end face. In other embodiments (not shown), the cartridge member may be formed from multiple elements assembled together (e.g., shell “halves” assembled by snap-fit engagement) to form the cartridge member. In some such embodiments, multiple cartridge member components may be snapped together over the pinch element, thereby eliminating the need for squeezed installation of the pinch element through the cartridge member.

[0057] As shown, the cartridge member 20 may include a single through passage 25 for retaining a single pinch element 40. In other embodiments (not shown), a pinch element subassembly may include a cartridge member having multiple through passages for retaining multiple pinch elements, for example, to facilitate simultaneous replacement of multiple pinch elements in a valve assembly.

[0058] FIGS. 4 A, 4B, and 4C illustrate another each exemplary pinch element subassembly 10' including a cartridge member 20', with grooved bearing portions 23', 24' retaining O- rings 31 ', 32' for sealing with a subassembly retaining passage, and a flexible pinch element 40' including a tubular portion 45' extending axially through a through passage 25' of the cartridge member 20', and first and second flanged end portions 41 ', 42' extending radially outward from the tubular portion, over and sealing against the first and second end faces 21 ', 22' of the cartridge member. As shown, the inner diameter of the cartridge member through passage 25' is substantially uniform, lacking the radially inward extending lip portions provided in the embodiment of FIGS. 3A, 3B, and 3C, for example, for ease of injection molding, and / or to reduce the volume of air required to activate / compress the pinch element /

[0059] While the tubular portion 45, 45' of the pinch element 40, 40' may be provided in a variety of contours and shapes, in the illustrated embodiment, as shown in FIGS. 3D and 4D, the tubular portion may include a central passage 47, 47' that is not circular in cross-section but rather has a cats-eye shape. The pinch element 40, 40' may further have a pair ofdiametrically opposed and longitudinally extending ribs 48, 48' along opposite sides of the tubular portion 45, 45'. These ribs 48, 48' provide a localized stiffness to the pinch element 40, 40' so that when the pinch element is exposed to external positive pressure, the portions 49, 49' of the pinch element between the ribs 48, 48' act as hinge points to allow the pinch valve to close without high stresses on the pinch element. These features are shown and described in co-owned U.S. Patent No. 10,989,316, the entire disclosure of which is incorporated herein by reference.

[0060] Pinch element subassemblies, as described herein, may be used with a variety of valve assemblies, including, for example, pump assemblies like the pump assemblies of the ‘878 Patent and FIGS. 1 A - 2B. FIG. 6 illustrates an exemplary valve assembly 100 configured to accommodate one or more pinch element subassemblies 110. The illustrated valve assembly 100 includes a valve body or valve housing block 150 assembled between first and second body blocks 160, 170 (e.g., by mounting fasteners, not shown). The valve housing block 150, which may be similar to the valve body 416 of the assemblies of FIGS. 1A - 1G and the ‘878 Patent, includes one or more axially extending through bores or pressure chamber bores 151, 152 extending between first and second ends 153, 154 of the valve housing block, each sized to receive and retain a pinch element subassembly 110 (e.g., the pinch element subassemblies 10, 10' of FIGS. 3A - 3C and 4A - 4C), with sealing portions 133, 134 of the cartridge member 120 sealing against the corresponding pressure chamber bore 151, 152. The first and second body blocks 160, 170, which may be similar to the upper and lower Y-blocks 424, 426 of the assemblies of FIGS. 1A - 1G and the ‘878 Patent, each include flow passages 161, 162, 171, 172 aligned with the pinch element tubular portions 145 within the through bores 151, 152 of the valve housing block 150. When the valve housing block 150 is assembled between the upper and lower body blocks 160, 170, the pinch element flange ends 141, 142 are axially compressed between the body blocks 160, 170 and the end faces 121, 122 of the cartridge member 120 to provide a leak tight seal. Additional gaskets or other such seals (not shown) may be provided between the valve housing block 150 and the body blocks 160, 170.

[0061] As shown, the valve housing block 150 may include includes air passages 155, 156 that communicate respectively with the pressure chamber bores 151, 152. These air passages 155, 156 may extend to an external surface of the valve assembly 100 (e.g., via vertical extensions extending through the valve housing block 150 to corresponding passages in the upper body block 160, not shown).

[0062] In this manner, each of the pressure chambers 151, 152 in the valve housing block 150 is configured to receive pressurized actuation fluid (e.g., air, nitrogen) from apressurization port (e.g. in a manifold module of the valve assembly, similar to the manifold body 414 of the assembly of FIGS. 1A - 1G). When positive air pressure is supplied to a selected one of the pressure chambers 151, 152 via the air passages 155, 156, the corresponding pinch element 140 is closed by the force of the air pressure acting against the outer flexible surface of the flexible pinch element. The pinch elements 140 open due to their own resilience and elasticity when external air pressure in the pressure chamber 151, 152 is removed. Each of the pinch elements 140 may thereby be separately controlled.

[0063] To replace one or more pinch elements 140 in the valve assembly 100, either or both of the body blocks 160, 170 may be disassembled from the valve housing block 150, so that the pinch element subassembly 110 may slide (e.g., in response to a pushing or pulling axial force) out of the corresponding pressure chamber 151, 152. While the pinch element 140 of the removed pinch element subassembly 110 may be extracted from the cartridge member 120 for replacement with a new pinch element, in some operations, the entire pinch element subassembly may be replaced, for example, to eliminate the time and effort required for pinch element replacement in the cartridge member. A new pinch element subassembly 110 may therefore be pushed into the corresponding pressure chamber 151, 152 before reassembly of the body block(s) 160, 170 with the valve housing block 150.

[0064] In some arrangements, according to another exemplary aspect of the present disclosure, one or more pinch element subassemblies may be installed in a cavity or passage of a pump body block, with integrated flow passage configurations, instead of being disposed in a separate valve housing block sandwiched between flow passage defining pump body blocks. For example, a pinch element subassembly may be received in a counterbore portion of a body block passage, with an end component or end connector (e.g., plate, coupling) assembled with (e.g., into or over) an end portion of the passage, such that the flanged end portions of the pinch element are axially compressed between the body block counterbore and the end connector. Such arrangements may, for example, allow for fewer components, fewer potential leak points, ease of assembly, and smaller footprint size, while still providing for ease of removal and replacement of the pinch elements.

[0065] FIGS. 6 and 6A illustrate an exemplary venturi style pump assembly 500 including a pump body 505 having an inlet port 501 at a first end and an outlet port 502 at a second end, with a central passage 503 extending from the inlet port to the outlet port. The exemplary pump body further defines a purge port 504, first and second actuator ports 506, 507, a flow port 508, and an atomizing port 509, described in greater detail below. As shown, one or more of the ports 501, 504, 506, 507, 508, 509 may be provided with installed fittings orconnectors 501a, 504a, 506a, 507a, 508a, 509a (e.g., push-to-connect cartridge fittings) to facilitate connection with fluid supply and delivery tubing of the fluid system (e.g., powder coating system).

[0066] The purge port 504 intersects with a mid-portion of the central passage 503, between a first pinch valve 510a operable to block purge air flow to the inlet port 501 and a second pinch valve 510b operable to block purge air flow to the outlet port 502. Similar to the embodiments of FIGS. 3 A - 3C and 4A - 4D, each exemplary pinch valve 510a, 510b may be provided as a pinch element subassembly 510 including a cartridge member 520 and a flexible pinch element 540 including a tubular portion 545 extending axially through the through passage 525 of the cartridge member 520, and first and second flanged end portions 541, 542 extending radially outward from the tubular portion, over and sealing against the first and second end faces 521, 522 of the cartridge member.

[0067] First and second actuator ports 506, 507 in the pump body 505 extend to the first and second pinch valves 510a, 510b, respectively, to selectively close the pinch valves. To purge the powder outlet 502 and any connected components (e.g., powder spray gun), pneumatic pressure is applied to the first actuator port 506, passing through cartridge member cross ports 527 into the cartridge member passage 525 of the first pinch valve 510a to close the first pinch valve, and purge gas is applied to the purge port 504. To purge the powder inlet 501 and any connected components (e.g., powder supply hopper or other powder source), pneumatic pressure is applied to the second actuator port 507, passing through cartridge member cross ports 527 into the cartridge member passage 525 of the second pinch valve 510b to close the second pinch valve, and purge gas is applied to the purge port 504.

[0068] In the illustrated embodiment, the pump body 505 is formed from a pump body block 505a defining the outlet port 502, the central passage 503, the purge port 504, and the actuator ports 506, 507, and a pump body plate 505b secured to the pump body block (e.g., by fasteners 505c) and defining the inlet port 501.

[0069] As shown in FIG. 6, the first and second pinch element subassemblies 510a, 510b may be retained in first and second counterbore portions 503a, 503b of the central passage 503. The flanged end portions 541, 542 of the pinch element 540 of the first pinch valve 510a may be axially compressed between a counterbore shoulder surface 503c of the first counterbore portion 503a and the pump body plate 505b. The flanged end portions 541, 542 of the pinch element 540 of the second pinch valve 510b may be axially compressed between a second counterbore shoulder surface 503d of the second counterbore portion 503b and the pump coupling 560 (described in greater detail below).

[0070] The flow port 508 and the atomizing port 509 intersect with the central passage 503 to supply suction generating pressurized air and powder diluting atomizing air, respectively, to a venturi unit 550 provided at the outlet end of the pump body 505, to direct the flow of fluidized powder through the outlet port 502 to a powder dispensing arrangement (e.g., spray gun). The venturi unit 550 includes a pump coupling 560 assembled with the outlet port 502 (e.g., secured by fasteners 561 tightened against an outer flange portion 562 of the pump coupling, as shown), an injector 570 retained in a lower (upstream) counterbore 563 of the pump coupling, and a throat element 580 and throat holder 590 seated in an upper (downstream) counterbore 564 of the pump coupling (e.g., by a nut 555 tightened on a male threaded end 554 of the pump coupling and against a shoulder portion 591 of the throat holder). The exemplary pump coupling 560 includes grooved bearing portions 565 with Ciring seals 566 for sealing with the pump body central passage 503. The exemplary injector 570 includes grooved bearing portions 571 with O-ring seals 572 for sealing with the lower counterbore 563 of the pump coupling 560, and the exemplary throat holder 590 includes grooved bearing portions 592 with O-ring seals 593 for sealing with the upper counterbore 564 of the pump coupling.

[0071] Pressurized flow air supplied to the flow port 508 passes through lower (upstream) openings 567 in the pump coupling 560 and into a duct 573 in the injector to exit through an injector nozzle 574 directing the air flow through the throat element 580. During the feeding of compressed air into the injector nozzle 574, a negative pressure is produced by the venturi principle in an annular space 575 surrounding the outlet of the injector nozzle, thereby drawing fluidized power through the inlet port 501 and forcing the fluidized powder material through the throat element 580. Pressurized atomizing air supplied to the atomizing port 509 passes through upper (downstream) openings 568 in the pump coupling 560 and through openings 594 in the throat holder 590 to pass along an annular gap 595 between the throat holder and the throat element 580 to exit the downstream end of the throat holder, for diluting or atomizing the fluidized powder as it exits the throat element.

[0072] While the pump assembly 500 may include a single set of fluid ports / passages 501, 502, 503, 504, 506, 507, 508, 509, flow isolating pinch valves 510a, 510b, and venturi unit 550, in some embodiments, a pump assembly may be provided with a single pump body accommodating multiple sets of fluid ports / passages, pinch valves, and venturi units, for example, for reduced footprint size, and / or to facilitate synchronized flow / actuation for multiple sets fluid ports / passages and pinch valves within a powder coating system. FIGS. 7A, 7B, and 7C illustrate an exemplary pump assembly 500' including a pump body 505'(e.g., pump body block 505a' and pump body plate 505b', as shown), including two sets of powder inlet ports 501-1 ', 501-2', powder outlet ports 502-1 ', 502-2', purge ports 504-1 ', 504-2', actuator ports 506-1 ', 506-2', 507-1 ', 507-2', flow ports 508-1 ', 508-2', atomizing ports 509-1 ', 509-2', and central passages 503-1 ', 503-2'. The two central passages 503-1 ', 503-2' accommodate corresponding pinch valves 510a-l ', 510a-2', 510b-l ', 510b-2', and venturi units 550-1 ', 550-2' (for example, with corresponding pump couplings, injectors, throat elements, and throat holders), which may be similar in structure, arrangement, and function to the corresponding components of the pump assembly 500 of FIG. 6. In still other embodiments, a pump assembly may be provided with a single pump body accommodating three or more sets of fluid ports / passages, pinch valves, and venturi units, for example, similar to the components shown and described herein. As shown in FIG. 7B, the pairs of first and second actuator ports 506-1 ', 506-2', 507-1 ', 507-2' may be joined (e.g., using T- fittings) to facilitate simultaneous actuation of the first actuator port and / or the second actuator ports.

[0073] In other arrangements, a pump assembly including integrated purge, flow, and atomizing porting and an installed venturi unit, as described herein, may be provided with different types of shutoff valves, including, for example, mechanically actuated pinch valves.

[0074] The inventive aspects have been described with reference to the exemplary embodiments. Modification and alterations will occur to others upon a reading and understanding of this specification. It is intended to include all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.

Claims

We claim:

1. A pinch element subassembly for a pinch valve, the pinch element subassembly comprising: a cartridge member including a through passage extending axially from a first end face of the cartridge member to a second end face of the cartridge member, a first end bearing portion extending radially outward of a central portion of the cartridge member to provide a first circumferential sealing portion, and a second end bearing portion extending radially outward of the central portion to provide a second circumferential sealing portion; and a flexible pinch element having a tubular portion extending axially through the cartridge member through passage, a first flanged end portion extending over and sealing against the cartridge member first end face, and a second flanged end portion extending over and sealing against the cartridge member second end face.

2. The pinch element subassembly of claim 1, wherein the central portion of the cartridge member is substantially cylindrical.

3. The pinch element subassembly of any of claims 1 and 2, wherein the central portion of the cartridge member includes at least one laterally extending cross port.

4. The pinch element subassembly of any of claims 1-3, wherein the cartridge member includes first and second annular ribs extending axially outward from the first and second bearing portions to define the first and second end faces.

5. The pinch element subassembly of any of claims 1-4, wherein the first and second end faces include rounded surfaces.

6. The pinch element subassembly of any of claims 1-5, wherein the cartridge member is sized to provide interference fit engagement between the first and second flanged end portions of the pinch element and the first and second end faces of the cartridge member.

7. The pinch element subassembly of any of claims 1-6, wherein the first and second flanged end portions of the pinch element extend radially beyond the first and second end faces.

8. The pinch element subassembly of any of claims 1-7, wherein the cartridge member includes first and second lip portions extending radially inward from the central portion of the cartridge member for engagement with the tubular portion of the pinch element, to define an annular gap between the central portion of the cartridge member and the tubular portion of the pinch element.

9. The pinch element subassembly of claim 8, wherein the first and second lip portions are at least partially axially aligned with the first and second end bearing portions.

10. The pinch element subassembly of any of claims 8 and 9, wherein the first and second lip portions define the first and second end faces.

11. The pinch element subassembly of any of claims 1-10, further comprising first and second gasket seals retained in first and second annular grooves in the first and second end bearing portions to define the first and second sealing portions.

12. A valve assembly compri sing : a valve housing block defining an axially extending through bore extending from a first end of the valve housing to a second end of the valve housing; a first body block secured to the first end of the valve housing block and including a first passage aligned with the valve housing block through bore; a second body block secured to the second end of the valve housing and including a second passage aligned with the valve housing block through bore; and a pinch element subassembly installed in the valve housing block through bore and comprising: a cartridge member including a through passage extending axially from a first end face of the cartridge member to a second end face of the cartridge member, a first end bearing portion forming a first circumferential seal between the cartridge member and the valve housing block through bore, and a second end bearing portion forming a second circumferential seal between the cartridge member and the valve housing block through bore; and a flexible pinch element having a tubular portion extending axially through the cartridge member through passage, a first flanged end portion axially compressedbetween the cartridge member first end face and the first body block and a second flanged end portion axially compressed between the cartridge member second end face and the second body block.

13. The valve assembly of claim 12, wherein the central portion of the cartridge member is substantially cylindrical.

14. The valve assembly of any of claims 12 and 13, wherein the central portion of the cartridge member includes at least one laterally extending cross port.

15. The valve assembly of any of claims 12-14, wherein the cartridge member includes first and second annular ribs extending axially outward from the first and second bearing portions to define the first and second end faces.

16. The valve assembly of any of claims 12-15, wherein the first and second end faces include rounded surfaces.

17. The valve assembly of any of claims 12-16, wherein the cartridge member is sized to provide interference fit engagement between the first and second flanged end portions of the pinch element and the first and second end faces of the cartridge member.

18. The valve assembly of any of claims 12-17, wherein the first and second flanged end portions of the pinch element extend radially beyond the first and second end faces.

19. The valve assembly of any of claims 12-18, wherein the cartridge member includes first and second lip portions extending radially inward from the central portion of the cartridge member for engagement with the tubular portion of the pinch element, to define an annular gap between the central portion of the cartridge member and the tubular portion of the pinch element.

20. The valve assembly of claim 19, wherein the first and second lip portions are at least partially axially aligned with the first and second end bearing portions.

21. The valve assembly of any of claims 19 and 20, wherein the first and second lip portions define the first and second end faces.

22. The valve assembly of any of claims 12-21, further comprising first and second gasket seals retained in first and second annular grooves in the first and second end bearing portions.

23. A valve assembly compri sing : a valve body block defining a central passage extending axially from a first end of the valve body block to a second end of the valve body block, the central passage including a first end counterbore portion at the first end of the valve body block; a first end connector assembled to the first end of the valve body block and providing a first end connection for the axially extending through bore; and a first end pinch element subassembly installed in the first end counterbore portion and comprising the pinch element assembly of any of claims 1-11, wherein the first flanged end portion is axially compressed between the cartridge member first end face and a shoulder surface of the first end counterbore portion, and the second flanged end portion is axially compressed between the cartridge member second end face and the first end connector.

24. The valve assembly of claim 23, wherein the valve body block further defines a first end actuation port intersecting with the first end counterbore portion to supply pressurized gas to compress the tubular portion of the flexible pinch element.

25. The valve assembly of any of claims 23-24, wherein the first end connector comprises a valve body plate secured to the first end of the valve body block.

26. The valve assembly of any of claims 23-24, wherein the first end connector comprises a coupling installed in the first end counterbore portion.

27. The valve assembly of any of claims 23-26, wherein the central passage includes a second end counterbore portion at the second end of the valve housing, with a second end connector assembled to the second end of the valve housing and providing a second end connection for the central passage, and a second end pinch element subassembly installed in the second end counterbore portion of the central passage and comprising the pinch element subassembly of any of claims 1-11, wherein the first flanged end portion of the second endpinch element subassembly is axially compressed between the cartridge member first end face and a shoulder surface of the second end counterbore portion, and the second flanged end portion second end pinch element subassembly is axially compressed between the cartridge member second end face and the second end connector.

28. The valve assembly of claim 27, wherein the valve body block further defines an second end actuation port intersecting with the second end counterbore portion to supply pressurized gas to compress the tubular portion of the flexible pinch element of the second pinch element subassembly.

29. A pump assembly comprising: a pump body including an inlet port at a first end, an outlet port at a second end, a central passage extending from the inlet port to the outlet port, a purge port intersecting with a mid-portion of the central passage, a flow port intersecting with an outlet portion of the central passage, and an atomizing port intersecting with the outlet portion of the central passage; a first shutoff valve installed in the central passage between the purge port and the inlet port; a second shutoff valve installed in the central passage between the purge port and the outlet port; and a venturi unit comprising: a pump coupling assembled with the outlet port; an injector retained in an upstream counterbore of the pump coupling; a throat holder retained in a downstream counterbore of the pump coupling; and a throat element retained in the throat holder; wherein when flow air is supplied to the flow port, the flow air passes through one or more upstream openings in the pump coupling and into a duct in the injector to exit through an injector nozzle directing the flow air through the throat element; and wherein when atomizing air is supplied to the atomizing port, the atomizing air passes through one or more downstream openings in the pump coupling and through one or more openings in the throat holder to pass along an annular gap between the throat holder and the throat element to exit a downstream end of the throat holder.

30. The pump assembly of claim 29, wherein the first shutoff valve comprises a first pinch valve and the second shutoff valve comprises a second pinch valve.

31. The pump assembly of claim 30, wherein the pump body comprises a first actuation port for supplying actuating fluid pressure to the first pinch valve, and a second actuation port for supplying actuating fluid pressure to the second pinch valve.

32. The pump assembly of any of claims 29-31, wherein the first and second pinch valves comprise first and second pinch element subassemblies, each of the first and second pinch element subassemblies comprising the pinch element subassembly of any of claims 1-11.

33. The pump assembly of claim 32, wherein the first pinch element subassembly is installed in a first end counterbore portion of the central passage.

34. The pump assembly of claim 33, wherein the pump body comprises a pump body block and a first end connector assembled to the pump body block to define the inlet port, wherein the first pinch element subassembly is axially compressed between a shoulder surface of the first end counterbore portion and the first end connector.

35. The pump assembly of claim 34, wherein the first end connector comprises a pump body plate mounted to the pump body block.

36. The pump assembly of claim 32, wherein the second pinch element subassembly is installed in a second end counterbore portion of the central passage.

37. The pump assembly of claim 36, wherein the second pinch element subassembly is axially compressed between a shoulder surface of the second end counterbore portion and the pump coupling.

Images