Piston Cartridge for Piston Pump

Patent metadata

Field	Value
Publication number	US-2018135622-A1
Application number	US-201615352284-A
Country	US
Kind code	A1
Filing date	Nov 15, 2016
Priority date	Nov 15, 2016
Publication date	May 17, 2018
Grant date	—

Abstract

A hydraulic piston pump includes a piston disposed in a blind housing bore of a piston housing and that reciprocates to generate a pumping action. To accommodate the piston, a piston cartridge is installed in each of the housing bores. The piston cartridge includes a piston sleeve having an inner sleeve periphery, a first outer sleeve periphery, and a second outer sleeve periphery. The inner sleeve periphery is configured to establish sliding contact with the piston. The first outer sleeve periphery has a first outer sleeve diameter that is larger than a second outer sleeve diameter associated with the second outer sleeve periphery. To seal against the blind housing bore, a liner cap having a cylindrical liner wall and an axial liner cover is disposed over the first outer sleeve periphery. The axial liner cover abuts a housing bore ceiling of the blind housing bore and can receive hydraulic fluid there through.

First claim

We claim:

1 . A hydraulic pump comprising:
a piston housing having a plurality of housing bores disposed therein each defining a bore axis, each of the plurality of housing bores further configured as a blind bore including a housing bore wall axially terminating in a housing bore ceiling; a plurality of pistons accommodated one each in the plurality of housing bores to reciprocatingly move with respect to the bore axis; and a piston cartridge concentrically installed in each of the plurality of housing bores, the piston cartridge including a piston sleeve having an inner sleeve periphery that defines a sleeve bore and is configured to allow movement of one of the plurality of pistons; the piston cartridge further having a liner cap disposed on the piston sleeve and having an axial liner cover extending over the sleeve bore configured to establish sealing contact with the housing bore ceiling.

2 . The hydraulic pump of claim 1 , wherein the axial liner cover further includes fluid aperture disposed therethrough that aligns with and receives hydraulic fluid from a fluid passage in the housing bore ceiling.

3 . The hydraulic pump of claim 2 , wherein the axial liner cover include an annular land to provide sealing contact with the housing bore ceiling.

4 . The hydraulic pump of claim 3 , wherein the annular land is an inner annular land disposed circumferentially proximate to the fluid aperture, and the axial liner cover includes an outer annular land disposed circumferentially about the inner annular land.

5 . The hydraulic pump of claim 1 , wherein the piston sleeve axially extends between a first sleeve end and a second sleeve end, the first sleeve end pressing the axial liner cover adjacent the housing bore ceiling.

6 . The hydraulic pump of claim 5 , wherein the piston sleeve including a first outer sleeve periphery proximate the first sleeve end and a second outer sleeve periphery proximate the second sleeve end.

7 . The hydraulic pump of claim 6 , wherein the first outer sleeve periphery has a first outer sleeve diameter and the second outer sleeve periphery has a second outer sleeve diameter that is larger than the first outer sleeve diameter.

8 . The hydraulic pump of claim 7 , wherein the liner cap includes a cylindrical liner wall extending from the axial liner cover, the cylindrical liner wall circumferentially disposed around the first outer sleeve periphery.

9 . The hydraulic pump of claim 8 , wherein the cylindrical liner wall has an outer liner diameter corresponding to the second outer sleeve diameter.

10 . The hydraulic pump of claim 9 , wherein the piston sleeve includes a plurality of radial apertures disposed through the second outer sleeve periphery, each of the plurality of radial apertures axially positioned between the first sleeve end and the second sleeve end to communicate with a groove disposed in the housing bore wall of each of the plurality of the housing bores.

11 . The hydraulic pump of claim 5 , wherein the piston sleeve is made of a relatively harder material than the liner cap such that the liner cap physically deforms between the first sleeve end and the housing bore ceiling.

12 . The hydraulic pump of claim 5 , wherein the piston sleeve includes a plurality of male threads disposed proximate the second sleeve end to engage corresponding female threads in each of the plurality of the housing bores.

13 . A cartridge for accommodating a piston in a housing bore, the cartridge comprising:
a piston sleeve extending between a first sleeve end and a second sleeve end; the piston sleeve including:
an inner sleeve periphery defining a sleeve bore and configured to allow reciprocating movement of the piston;
a first outer sleeve periphery extending from the first sleeve end and having a first outer sleeve diameter; and
a second outer sleeve periphery extending from the second sleeve end and having a second outer sleeve diameter larger than the first outer sleeve diameter;
a liner cap having a cylindrical liner wall defining a liner bore and radially disposed around the first outer sleeve periphery, the liner cap further having an axial liner cover extending over the liner bore and having a fluid aperture disposed there through to receive hydraulic fluid into the sleeve bore.

14 . The cartridge of claim 13 , wherein the axial liner cover includes an annular land concentrically disposed around the fluid aperture for establishing sealing contact with a surface located the housing bore.

15 . The cartridge of claim 14 , wherein is an inner annular land disposed circumferentially proximate to the fluid aperture, and the axial liner cover include an outer annular land disposed circumferentially about the inner annular land.

16 . The cartridge of claim 13 , wherein the in the piston sleeve is made from a relatively harder material than the liner cap.

17 . The cartridge of claim 13 , wherein the piston sleeve includes a plurality of male threads proximate to the second sleeve end to engage correspond female threads in the housing bore.

18 . A cryogenic pump assembly comprising:
a pump body extending along a pump axis between a pump assembly and a drive assembly; the pump assembly including a plurality of pumping elements disposed radially around the pump axis; the drive assembly including a piston housing having a plurality of housing bores disposed in a radial arrangement about the pump axis each defining a bore axis, the piston housing further including a plurality of fluid passages each configured to direct fluid to one of the plurality of housing bores; a plurality of pistons disposed within each of the plurality of housing bores, each of the plurality of pistons arranged to reciprocatingly drive a corresponding one of the plurality of pumping elements; a piston cartridge concentrically installed in each of the plurality of housing bores, the piston cartridge including a piston sleeve and a liner cap, the piston sleeve having an inner sleeve periphery delineating a sleeve bore and configured to establish sliding contact with one of the plurality of pistons, the liner cap including axial liner cover extending over the sleeve bore and having a fluid aperture configured to establish fluid communication with one of the plurality of fluid passages.

19 . The cryogenic pump assembly of claim 18 , wherein each of the plurality of housing bores is configured as a blind bore including a housing bore wall axially terminating at a housing bore ceiling, and the axial liner cover of the liner cap further includes an annular land to provide sealing contact with the housing bore ceiling.

20 . The cryogenic pump assembly of claim 19 , wherein the piston sleeve includes a plurality of radial apertures disposed therein and axially positioned to communicate with a groove disposed in the housing bore wall.

Assignees

• Caterpillar Inc

Inventors

• Bean Sunil J
• Brown Cory A

Classifications

• F04B53/144

  Adaptation of piston-rods · CPC title

• F04B9/1176

  the movement of each piston in one direction being obtained by a single-acting piston liquid motor · CPC title

• F04B1/128

  Driving means · CPC title

• F04B1/12

  having cylinder axes coaxial with, or parallel or inclined to, main shaft axis · CPC title

• F04B2015/081

  Liquefied gases · CPC title