Compact twin piston pump

• US 4,869,653 A
• Filed: 06/16/1988
• Issued: 09/26/1989
• 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: Currier, Joseph G., Powers, Richard G., Zeets, Joseph S.
• Primary Examiner(s): NOT, DEFINED
• Assistant Examiner(s): NOT, DEFINED
• Application Number:
  US07/207,889
• Time in Patent Office: 467 Days
• Field of Search: 417/339, 417/360, 417/361, 417/401, 417/454, 417/469, 417/516, 417/900, 251/175, 137/625.8, 137/625.4
• US Class Current: 417/339
• 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

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 ducy 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. A piston-type pump, comprising:

means defining a chamber having a material inlet and a material outlet;

an elongated, tubular, axially shiftable sleeve having a rearward end and a forward end;

means mounting said sleeve adjacent said chamber for permitting movement of the sleeve between a retracted position allowing material within the chamber to enter the forward end of the sleeve, and an extended pumping position with the forward end of the sleeve in registry with said outlet allowing material within the sleeve to be pumped out said outlet;

a piston having a rearward connection end and a forward pumping face, said piston being slidably positioned within said sleeve and movable between a retracted position and a forward position adjacent the sleeve forward end;

a pair of hydraulic piston and cylinder assemblies each having a shiftable rod and respectively located for attachment to said sleeve and piston for corresponding movement of each of the same; and

means coupling said assemblies to said sleeve and piston respectively for permitting rapid disassembly thereof to facilitate pump cleanup, said coupling means including first connection structure pivotally connecting one of said rods with said sleeve adjacent the rearward end thereof, and second connection structure pivotally and releasably connecting the other of said rods with said piston adjacent said connection end thereof;

said first and second connection structures cooperatively permitting pivotal movement of the sleeve and piston away from said chamber and about axes transverse to the longitudinal axis of the sleeve,

said second connection structure including means for rapid disconnection thereof to free said piston, whereby said piston may be removed from the rearward end of said sleeve for cleanup purposes when the sleeve and piston are pivoted away from said chamber.

2. The pump of claim 1, said first and second connection structures each comprising a yoke and clevis assembly.

3. The pump of claim 1, including a sleeve guide for slidably receiving said sleeve, said guide comprising a first rigid portion and a second releasable portion, said first and second portions cooperatively defining a sleeve-receiving body, there being means detachably securing said second portion to said first portion.

4. A piston-type pump comprising:

a pair of side-by-side pumping assemblies each including an elongated tubular member adapted to receive material to be pumped and an outlet opening for such material, and a piston slidably positioned within said member for pumping said material out the corresponding outlet opening;

valve means located proximal to said outlet openings for controlling flow of material therefrom, said valve means including-a

rear plate adjacent said outlet openings and having a pair of apertures there-through 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 further 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 further 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 associated with said valve 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.

5. The pump of claim 4, said biasing means comprising means for exerting a pressure on the face of said second plate member remote from said pumping assemblies in excess of the pressure exerted on the face of the second plate member adjacent said pumping assemblies, whereby said second plate member is urged into sealing relationship with an associated rear plate aperture.

6. The pump of claim 5, said pressure-exerting means comprising a bifurcated tubular outlet operatively coupled with and communicating said front plate holes and presenting a product discharge port such that material pumped under pressure through one of said front plate holes contacts the face of the second plate member remote from said pumping assemblies, there being means for maintaining the pressure exerted on the face of said second plate member adjacent said pumping assemblies at a level less than the pressure of said pumped material, when the valving plate assembly is in either of said extreme positions thereof.

7. A piston-type pump consisting:

a pair of side-by-side pumping assemblies each including an elongated tubular member adapted to receive material to be pumped and an outlet opening for such material, and a piston slidably positioned within said member for pumping said material out the corresponding outlet opening;

valve means located proximal to said outlet openings for controlling flow of material therefrom, said valve means including

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, 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 seals respectively disposed adjacent opposite faces of said valving plate assembly and of a size to circumscribe said apertures and openings, said valving plate assembly being of a size to maintain constant contact with the entirety of each of said circumscribing seals in all operational positions of said valving plate assembly, whereby to maintain the sealed integrity of the valve means and inhibit the flow of said material into said channel.

8. The piston type of claim 7, said seals being respectively seated in corresponding recesses provided in said rear and front plates, said valving plate assembly being shiftable relative to said seals.