US3788197A

US3788197A - Fluid lift mechanism and underground housing

Info

Publication number: US3788197A
Application number: US00176480A
Authority: US
Inventors: B Bishop
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-08-31
Filing date: 1971-08-31
Publication date: 1974-01-29
Anticipated expiration: 1991-01-29

Abstract

A pre-molded electrical insulating housing for receiving an underground metal portion of a fluid operated expansible chamber lift mechanism to protect the mechanism from corrosion. The housing includes means for protecting the associated piping effecting operation of the lift mechanism and the lift movement guiding assembly.

Description

United States Patent 1191 Bishop 1 1 Jan. 29, 1974 [5 FLUID LIFT MECHANISM AND 3,507,120 4/1970 Rohmer 61/.5 UNDERGROUND HOUSING 3,203,396 8/1965 Carmichael 52/170 3,403,520 10/1968 Goodman 52/170 Inventor: Billy p, 1111 S. Post a 3,207,046 9/1965 McAlpine 92/77 Houston, Tex. 77027 a Prima Examiner-Charles J. M hre A .31, 1971 Y [22] plld ug Assistant Examiner-R1 H. Lazarus [21 Appl. No.: 176,480 Attorney, Agent, or Firm Pravel, Wilson & Matthews 52 us. 01. 92/77 1571 ABSTRACT [51 J Int. Cl. F01b 29/00 A ti -m l tr insulat ng housing for receiv- [58] Field of Search 92/1, 77; 61/5; 52/170; ing an underground metal Portion of a fluid Operated 174/17 LP, 37, 17 R expansible chamber lift mechanism to protect the mechanism from corrosion. The housing includes [56] References Cited means for protecting the associated piping effecting UNITED STATES PATENTS operation of the lift mechanism and the lift movement 3,644,858 2/1972 Galloway 174 17 LF gudmg assembly 3,465,527 9/1969 Rohmer 61/5 8 Claims, 8 Drawing Figures PATENTED JAN 2 91974 SHEET 1 OF 2 1 lllllllllllll SHEET 2 BF 2 vPATENTEDJAM291914 FLUID LIFT MECHANISM AND UNDERGROUND HOUSING BACKGROUND OF THE INVENTION This invention relates to a method and apparatus for controlling corrosion of an underground metal portion of a fluid operated lift mechanism.

Hydraulic lifts have been widely employed in numcr ous services for many years. One of the most common uses was in elevating an automobile to facilitate the performance of maintenance work on the. automobile. When employed in this manner, a portion of the lift was positioned in the ground where it was subject to eventual damage and destruction from corrosion. The frequent washdowns of the automobile repair bay provided the necessary moisture to effect a galvanic cell for corroding of the underground portions of the lift. To provide temporary corrosion protection to the lift, the casing was either coated by being wrapped and doped or a sacrificial anode was employed to protect the cathodic lift mechanism. When the lift was wrapped and doped any opening or holiday in the coating tended to concentrate the metal loss which accelerated the damaging effect of the corrosion on the lift. The sacrificial anodes were often not replaced after they were consumed which left the lift without any protection. If the sacrificial anodes were employed with a rectifier to insure the proper direction of electrical current flow, the lift protection system was costly to operate and maintain.

SUMMARY OF THE INVENTION I BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view, in section, of one form of the corrosion control apparatus of the present invention having one form of a lift mechanism positioned therein;

FIG. .2 is a perspective view of the form of the corrosion control apparatus illustrated in FIG. 1;

FIGS. 3 and 4 are views taken along lines 33 and 44, respectively, of FIG. 1;

FIG. 5 is a side view, in section, of a second form of the corrosion control apparatus of the present invention having a second form of a lift mechanism positioned therein; 4

FIG. 6 is a perspective view of the form of the corrosion control apparatus illustrated in FIG. 5; and

FIGS. 7 and 8 are views taken along lines 77 and 8-8, respectively, of FIG. 5.

DESCRIPTION OF THE PREFERRED EMBODIMENT Attention is directed to the FIGS. where the corrosion control apparatus of the present invention is illustrated. The corrosion control apparatus, designated A, is used to protect an underground portion of a hydraulie lift mechanism L used to elevate a load with a piston rod R from the destructive effects of corrosion. Both semi-hydraulic (FIG. 1) and full hydraulic (FIG. 5) single post lifts L may be protected with the present invention.

The corrosion control apparatus A includes a premolded housing H for receiving at least a portion of the lift mechanism L. The housing H includes a side wall 10 having an open upper end ll and a bottom wall 12 closing the lower end of the housing H. The side wall 10 and the bottom wall 12 form a recess 13 in the housing H for receiving and containing the lift mechanism L. The lift mechanism L includes a casing or cylindrical member C having a lower annular shoulder surface B adapted to engage the lower wall 12 for supporting the casing C in the recess 13 of the housing 10. The movable piston rod R extends upwardly from the cylinder C.

As illustrated in FIG. 1, the housing H includes a preformed outwardly projecting longitudinally extending ridge-like portion 14 which extends from the open upper end 1 l to a location below the bottom wall 12 to provide a passageway alongside the cylinder C for an operating fluid conduit or pipe P connected to the lower annular shoulder B of the cylinder C. The pipe P has an insulated fitting I therein for electrically insulating the pipe P to prevent transmission of corrosion inducing electrical current through the pipe P to the casing C.

The housing 10 includes a pair of preformed outwardly projecting ridge-like portions 15 extending downwardly a short distance from the open upper end 11. The enlarged recess 13 adjacent the ridge portion 15 provide movement enabling clearance to thehousing H about the heads of a pair of threaded members (not illustrated) extending inwardly into the casing C to provide an upper movement limit stop to the piston P of the lift mechanism L.

The housing H includes a preformed outwardly projecting portion 16 which extends downwardly from the open upper end 11 to a location above the lower wall 12. The enlargement of the recess 13 provided by the portion 16 enables a lift movement guiding antirotationdevice M having a gravity operated lift lock to be positioned within the recess 13 of the housing H.

As illustrated in FIG. 5 the full hydraulic embodiment of the lift mechanism L has the operating fluid pipe P connected to the'upper portion of the casing C. This difference eliminates the need for the pipe passageway ridge 14 resulting in a simplified second embodiment of the corrosion control apparatus A. Like reference characters are used to identify corresponding portions present in both embodiments of the corrosion control housing H. The self-standing housing H is formed from an elec trical non-conducting material to electrically insulate the underground portion of the lift mechanism positioned in the recess 13. Preferably, the sleeve 10 is preformed from a polyester resin plastic material such as polyvinyl acetate or methyl methacrylate, preferably having fiberglass reinforcing to strengthen the housing H. A polyester resin rich gel coat on the exterior of the housing H enhances the resistance to moisture penetration of the housing H to provide a spaced water barrier about the cylinder C. Adequate structural strength, water proofing and the desired electrical insulating properties have been achieved by forming the

walls

10 and 12 from a one-eighth-inch thickness of the polyester resin with a 1 mil thick gel coat.

The corrosion control apparatus A includes a seal means 17 to effect an annular seal between the housing H and the lift mechanism L adjacent the open upper end 11. The seal means 17 blocks passage of moisture into the recess 13 below the effected seal as well as forming a chamber in the bore 11 below the seal 17 for confining the underground portions of the lift mechanism L therein. By filling the recess 13 with a corrosion inhibiting fluid, such as oil, leakage of fluid past the seal means 17 into the bore 11 will be prevented.

In the use and operation of the present invention, a suitable excavation to receive the preformed housing and the cylinder C of thelift mechanism L is dug. If the semi-hydraulic lift mechanism L, illustrated in FIG. 1, is to be installed, the piping P to extend alongside the cylinder C in the portion 14 to the insulating fitting I is then connected to the cylinder C.

The cylinder C of the lift mechanism L is then wiped clean from dirt or rust and a light coat of oil is applied to the exterior of the cylinder C. The cylinder C is then aligned with the recess 13 and the housing H placed over the cylinder C by inserting the cylinder C into the recess 13 until the lower shoulder B engages the bottom .wall 12 of the housing H. The housing H and the casing C are then placed in the excavated hole with the lift mechanism L in the normal operating position. A small amount of concrete D is carefully poured around the exterior of the housing 10 to be worked under the bottom wall 12 of the housing 10 for supporting the housing 10 and the lift mechanism '1... The concrete D is allowed to set up before back filling the excavation with clean, dry sand E for providing lateral support to the housing H and the lift mechanism L. i

The recess 13 is then filled with oil to eliminate any moisture from forming inside the housing H where it would come in contact with the lift mechanism L. The annular area between the cylinder C, the movement device M and the housing H adjacent the open upper end 11 is then sealed at 17 by asuitable braided packing material. As illustrated in FIG. 1, the seal 17 is also effected with the piping Pin the semi-hydraulic embodiment of the lift mechanism L. The pipe P above the seal 17 extending to the insulatedfitting l is wrapped or coated to protect the pipe P from moisture and block formation of a galvanic cell which would corrode the pipe P or the casing C. The seal 17 forms an enclosed chamber 18 which confines the underground portions is then coated with a corrosion resistant material such as wrapping with a plastic tape. This wrapping not only protects the lift mechanism L from corrosion but also prevents adherence of a poured concrete floor F to the upper portions of the cylinder C. Preferably, the thickness of the concrete floor F is sufficient to extend from a position adjacent the upper edge of the cylinder C to a position below the seal 17 and the open upper end 11 of the housing H. The remainder of the installation of the lift mechanism L is then completed in the normal manner.

It will be immediately appreciated that the ease of installation of the protective housing H as well as the superior permanent protection afforded to the lift mechanism make the present invention extremely desirable. While two embodiments of the housing 10 are illustrated, many different shapes may be preformed for different conditions and different shaped lift mechanisms L.

The foregoing disclosure and description of the invention are illustrative and explanatory thereof, and various changes in the size, shape and materials as well as in the details of the illustrated construction may be made without departing from the spirit of the invention.

What is claimed is: l. A corrosion control apparatus with a fluid lift mechanism adapted to be disposed underground, comprising:

a fluid lift mechanism including a cylinder portion; a pre-molded housing closely conforming to and having therein at least the cylinder portion of the fluid lift mechanism, with a recess surrounding the cylinder portion which is narrow enough to prevent substantial lateral shifting of the cylinder in the housing; said housing having a bottom wallbelowthe cylinder portion upon which the cylinder portion rests and a side wall integral with said bottom wall surrounding the cylinder portion and extending upwardly from said bottom wall to an open upper end substantially at the top of the cylinder portion, and said side wall having its lower end terminating at said bottom wall so as to be coterminous therewith;

said housing being formed of an electrical nonconducting material to insulate the cylinder portion of a fluid lift mechanism from corrosion effecting electrical currents wherein said housing electrically insulates the cylinder portion to control corrosion of the lift mechanism; and

corrosion inhibiting fluid in said recess isolating said housing is molded of a plastic resin.

4. The invention as set forth in claim 3 wherein said plastic resin includes a rigid polyester resin.

5. The invention as set forth in claim 3 wherein said plastic resin is reinforced with fiberglass to strengthen the housing.

6. The invention as set forth in claim 2 including:

seal means for effecting a seal between said lift mechanism and an upper portionof said side wall for blocking passage of moisture into said housing and thus forming a closed chamber for confining said lift mechanism therein wherein said underground portion of said lift mechanism is isolated from the underground corrosion producing conditions.

supported; a concrete floor surrounding the upper end of the cylinder portion extending above said housing; and a moisture-proof seal in the upper end of said housing and covered by said concrete floor for sealing off the upper end of said housing.

Claims

1. A corrosion control apparatus with a fluid lift mechanism adapted to be disposed underground, comprising: a fluid lift mechanism including a cylinder portion; a pre-molded housing clOsely conforming to and having therein at least the cylinder portion of the fluid lift mechanism, with a recess surrounding the cylinder portion which is narrow enough to prevent substantial lateral shifting of the cylinder in the housing; said housing having a bottom wall below the cylinder portion upon which the cylinder portion rests and a side wall integral with said bottom wall surrounding the cylinder portion and extending upwardly from said bottom wall to an open upper end substantially at the top of the cylinder portion, and said side wall having its lower end terminating at said bottom wall so as to be coterminous therewith; said housing being formed of an electrical non-conducting material to insulate the cylinder portion of a fluid lift mechanism from corrosion effecting electrical currents wherein said housing electrically insulates the cylinder portion to control corrosion of the lift mechanism; and corrosion inhibiting fluid in said recess isolating said cylinder from moisture to thereby assure the absence of galvanic action with the cylinder portion of the fluid lift mechanism.

2. The invention as set forth in claim 1 wherein: said housing material is also a moisture proof material to provide a spaced water barrier about the lift mechanism wherein said housing prevents moisture contact with the underground portion of the lift mechanism to control corrosion of the lift mechanism.

3. The invention as set forth in claim 2 wherein said housing is molded of a plastic resin.

6. The invention as set forth in claim 2 including: seal means for effecting a seal between said lift mechanism and an upper portion of said side wall for blocking passage of moisture into said housing and thus forming a closed chamber for confining said lift mechanism therein wherein said underground portion of said lift mechanism is isolated from the underground corrosion producing conditions.

7. The invention as set forth in claim 2 including: said housing having a preformed portion closely conforming with an operating fluid line disposed alongside the cylinder portion but also having a recess therebetween, whereby said housing protects the operating fluid line from the effects of corrosion.

8. The apparatus set forth in claim 1, including: a concrete base pad upon which said bottom wall is supported; a concrete floor surrounding the upper end of the cylinder portion extending above said housing; and a moisture-proof seal in the upper end of said housing and covered by said concrete floor for sealing off the upper end of said housing.