Compact twin piston pump

• US 4,884,594 A
• Filed: 02/09/1989
• Issued: 12/05/1989
• Est. Priority Date: 10/07/1987
• Status: Expired due to Fees

• Current Assignee: MRC Holdings, Inc. (Citigroup Incorporated)
• Original Assignee: MRC Holdings, Inc. (Citigroup Incorporated)
• Inventors: Powers, Richard G., Zeets, Joseph S., Currier, Joseph G.
• Primary Examiner(s): RIVELL, JOHN A
• Application Number:
  US07/308,208
• Time in Patent Office: 299 Days
• Field of Search: 137/625.48, 137/625.49, 137/625.4, 417/900, 251/175
• US Class Current: 137/625.48
• CPC Class Codes: F04B 15/023 supply of fluid to the pump by gravity through a hopper, e.g. without intake valve
• CPC Class Codes: F04B 53/147 Mounting or detaching of piston rod
• CPC Class Codes: F04B 7/003 and having a slidable movement
• CPC Class Codes: F04B 7/0088 Sealing arrangements between the distribution members and the housing
• CPC Class Codes: F04B 7/025 and having a slidable movement
• CPC Class Codes: F04B 7/0291 the distribution being realised by moving the cylinder itself, e.g. by sliding or swinging
• CPC Class Codes: Y10S 417/90 Slurry pumps, e.g. concrete
• CPC Class Codes: Y10T 137/86879 Reciprocating valve unit

Abstract

A compact, relatively low cost twin piston pump (20) especially adapted for the pumping of foods (e.g. juices, puddings or particulates such as stews and chilies) is provided which includes quick detach yoke and clevis assemblies (108, 124, 110, 126) connecting the reciprocable pistons (100, 102) with their associated hydraulic cylinders (116, 118), thereby permitting quick cleanup of the machine (20). A jacking screw plate (136) is used for forward mounting of the piston and cylinder assemblies (84, 86, 116, 118) coupled with the sleeves (42, 44) and associated pistons (100, 102). This permits precise adjustment of the working components of the machine, while eliminating expensive bearings and heavy duty framing members. The pump (20) is also provided with a slide plate-type valve (38, 184) for controlling output of product from the pump (20). In one valve embodiment (184) a two-part metallic slide plate assembly (192, 200) is sandwiched between a pair of apertured nylon plates (186). One of the slide plate parts (200) is of lesser thickness than the primary part (192), so as to permit limited fore-and-aft movement of the part (200) for sealing purposes. A unique hydraulic system employing a master pressure reducing valve (222) and a slaved pressure reducing valve (224) is employed for creating a pressure differential across the part (200) in order to bias the same for sealing purposes.

Claims

1. Valve means adapted for coupling to a source of pressurized, flowable material which delivers said material from a pair of spaced outlet openings, said valve means comprising:

a rear plate adjacent said outlet openings and having a pair of apertures therethrough in registry with said outlet openings;

a front plate in face-to-face relationship with said rear plate and having a pair of holes therethrough in alignment with said apertures;

means operatively connecting said front and rear plates together,

there being a channel defined between said front and rear plates;

a valving plate assembly situated within said channel and slidable between a first extreme position completely blocking one of said apertures while permitting free flow through the other of said apertures, and a second extreme position completely blocking said other aperture and permitting free flow through said one aperture,

said valving plate assembly including structure for, at an intermediate position thereof between said extreme positions, permitting simultaneous partial flow of material from both of said apertures,

said valving plate assembly comprising a first plate having a thickness and a continuous opening therethrough,

said first plate opening including respective endmost portions configured for registry with associated rear plate apertures, said endmost portions being farther apart than said rear plate apertures and being interconnected by an elongated connection portion, there being a second, free floating plate member within said elongated connection portion, said second plate member having a thickness less than said first plate and being sized for covering said one aperture when said valving plate assembly is in said first extreme position thereof, and for covering the other of said apertures when said valving plate assembly is in said second extreme position thereof,

there being means for biasing said free floating second plate member towards an associated rear plate aperture when the valving plate assembly is in said extreme positions thereof.

2. Valve means adapted for coupling to a source of pressurized, flowable material which delivers said material from a pair of spaced outlet openings, said valve means comprising:

a rear plate adjacent said outlet openings and having a pair of apertures therethrough in registry with said outlet openings;

a front plate in face-to-face relationship with said rear plate and having a pair of holes therethrough in alignment with said apertures;

means operatively connecting said front and rear plates together,

there being a channel defined between said front and rear plates;

a valving plate assembly situated within said channel, presenting an opening therethrough having an open area greater than either of said apertures or holes, and slidable between a first extreme position completely blocking one of said apertures with said opening out of communication with said one aperture while permitting free flow through the other of said apertures and through said opening, and a second extreme position completely blocking said other aperture with said opening out of communication with said other aperture, while permitting free flow through said one aperture and said opening,

said opening being oriented on said valving plate for, at an intermediate position thereof between said extreme positions, permitting simultaneous partial flow of material from both of said apertures, through said opening,

there being a pair of inner seals respectively disposed adjacent opposite faces of said valving plate assembly and each of said seals being of a size to circumscribe said pair of apertures and said pair of holes and said opening, said valving plate assembly being of a size to maintain constant contact with the entirety of each of said inner seals in all operational positions of said valving plate assembly, whereby to maintain the sealed integrity of the valve means; and

two pairs of outer seals, one pair thereof being disposed adjacent the face of said front plate remote from said valving plate and respectively in circumscribing relationship with said front plate holes, the other pair of outer seals being disposed adjacent the face of said rear plate remote from said valving plate and respectively in circumscribing relationship with said rear plate apertures.

3. The valve means of claim 2;

said seals being respectively seated in corresponding recesses provided in the faces of said rear and front plates adjacent said valving plate assembly, said valving plate assembly being shiftable relative to said seals.