US2530138A - Jack - Google Patents

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US2530138A
US2530138A US711648A US71164846A US2530138A US 2530138 A US2530138 A US 2530138A US 711648 A US711648 A US 711648A US 71164846 A US71164846 A US 71164846A US 2530138 A US2530138 A US 2530138A
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piston
leg
jacks
jack
housing
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US711648A
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Wallace Paul Eugene
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B66HOISTING; LIFTING; HAULING
    • B66FHOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
    • B66F3/00Devices, e.g. jacks, adapted for uninterrupted lifting of loads
    • B66F3/24Devices, e.g. jacks, adapted for uninterrupted lifting of loads fluid-pressure operated

Definitions

  • XMMIQM to .var ious loads and various shapes. sembly of. a plurality of jacksinto a working unit .permits the load carrying capacity of the unit 1 jack. can be made.
  • the device .to .be described herein is particularly adaptedfor. usein motor vehiclerepair.
  • My novel jack is'especially adapted for re1atively high work and it is particularly adaptable The asto. be increased and permits the lifting heads to ..be,so 'assembled that they are able .to contact the object to be lifted at advantageous points.
  • Figure 1 is an elevation of thejack which is partly in .section.
  • Eigure 2 is a sidegelevation of Figure 1.
  • FigureS is a. section on the line 3 3 of Figure 2.
  • Figure 4 is an elevation ofadouble unit which consists of the assemblygof two 1 of the jacks shown in Figures 1 through 3.
  • FIG. 5 isasection on the line 55 of Fig- In Figure 1 an individual jack I0 is illustrated.
  • the jack comprises a housing H and stationary tubular column 12.
  • the column "ll-is retained .in a vertical position 'andhas its lower en'd sealed by a plu l3 and itsupper endsealed by bearing '14. in the co1umn.l2 and has apiston rod IS secured tothe upper portion .ofthe piston.
  • The, bearing It has an opening which the piston rod pene- A hydraulic piston. is slidablymounted trates.
  • a suitable lifting head .11 provided with clamping screws is secured to the upper end of v the piston rod H5.
  • the housing II is hollow and supports aplurality (preferably-three) of horizontal legs .58.
  • the legs 58 are hollow and form an oil reservoir l8- in .combinationwith the hollow interior of the housing.
  • a threaded plug 19 in housing ll provides an inlet by which oil may be added to the. reservoir.
  • the column 12 is supported in .lor using;ll at two points.- It contacts the lower and provides a fulcrum for a laterallyfeiitehding handle;ZB which isi pivotally mounted on collar 21 atZ Q.
  • connecting rod 1s rotatablycon- .,nected to an intermediate portionof 'the'h andle at 3l. 1 Manual-operation of the handle reciprocates the piston- 24 through the connectingrod'iill and piston rod 2 6.
  • I A tool tray 32 may be mounted on the column I2'if desired. The'trayis preferfairly rotatable relative -to the column.
  • a one way check valve 39 permits fluid to ⁇ travel spat a 8 .tof' a s si i s e e ment of fluidin the opposite direction.
  • permits fluid to travel from chamber "IE to cylinder 23 butprevents the return'movement-thereof.
  • Qrifices 42 and l3 are fprovided in the upper portion of the wall of cylinder 23 and connect the y nd r withthes ambrs J T @93 respectively,
  • a bleedhole 14 is provided inthe upp r mr ig tt .q l imnjl so h ther cape from ,or ,enter thecolumn l2 as" the 'piston :m th r1i
  • closes and valve 39 opens permitting oil to travel from cylinder 23, through orifice 38, past valve 39 into passages 31, 36, and into the pressure chamber below piston l5.
  • the entrance of this oil forces piston l5 upward.
  • valve 39 When the piston 24 has completed its downward stroke and begins to rise the pressure of the piston l5 on the oil below it closes valve 39.
  • the oil trapped below .piston l5 by the closed valve 39 supports the piston l5 until the next successive downward motion of piston 24 again raises piston [5.
  • a valve controlled bleed back to return oil from the chamber below piston IE to the chamber I8 is provided as a means of lowering the piston l5 and lifting head ll.
  • is vertically disposed in the base of supplemental housing 22 and the upper end of cylinder 5
  • a small piston 52 is slidably mounted in cylinder 5
  • a piston rod 53 extends upwardly from piston 52 l and projects through an aligned opening in the upper portion of supplemental housing 22.
  • the piston rod 53 is provided with spaced abutments 54 and 55 which are adapted to engage the upper and lower portions, respectively, of the supplemental housing 22 and limit movement of the piston rod 53.
  • the abutments are so spaced relative to rod 53 and housing 22 that limited movement of the piston 52 is permitted.
  • a spring 55 ton 52 exposes the upper portion of cylinder 5
  • Each individual jack has been illustrated as provided with 3 legs 58 although'more legs could be provided if desired.
  • Each leg is supported by a caster 60.
  • Legs 58 in Figure 3 illustrate one means by which a caster 6
  • Each caster 60 comprises a housing 6
  • a wheel 63 and a bifurcated element 64 are adapted to rotatably support said wheel.
  • the bifurcated element 64 has a vertical shaft portion 65 which is rotatably mounted in the opening 62 of housing 6
  • the constructionillustrated on legs 53' of Figure 3 shows a collar 66 which is secured The collar 66 circumscribes the end portion of leg 58 and is secured thereto as by welding.
  • a suitable plug 61 covers the end of leg 58' so that oil will be retained in the leg.
  • This caster construction is of a permanent nature and does not admit of the removal of the caster.
  • a second construction of the caster and leg is designed for use on one or more legs to facilitate the joinder of two or more individual jacks.
  • the end portion of the leg 58 is provided with a vertical flange 10.
  • of the caster is provided with a cooperating vertical plate II which has an external contour that is generally similar to the external contour of the flange 10. The flange 10 and vertical When piston rod 53 is bolted together.
  • are provided with aligned openings (not shown) by means of which bolts 12 may be used to secure the plate H to the flange 10.
  • Corresponding legs of individual jacks may be joined as illustrated in Figures 4 and 5 by removing the bolts 12 and the casters 60 and placing the flanges 10 of the corresponding legs in contact. The bolts 12 may then be inserted and the flanges ill of individual jacks A section of pipe I3 illustrated in dotted lines in Figure 4 may be inserted during assembly to strengthen the joint if desired.
  • a drain plug 75 may be provided in the bottom of housin M if desired so that oil may be drained from the reservoir l8 preparatory to the joinder of individual jacks and so that removal of a caster will not cause a loss of oil. If desired the end of leg 58 may be permanently sealed to prevent the loss of oil although such a construction would not admit of the use of pipe 13.
  • each leg of each jack is provided with a removable caster as illustrated in the drawings then two jacks may be joined. If more than one leg of each jack is provided with a removable caster then an unlimited number of jacks may be joined.
  • the joinder of a plurality of jacks permits the total weight of the load to be distributed between the jacks. Individual manipulation of joined jacks permits the lifting heads to be adjusted so that they will engage the particular contour of the object to be lifted or lowered to their best advantage.
  • a plurality of independently operable jacks each comprising a lifting head, a base, hydraulic means associated with said bases for elevating said lifting heads, a plurality of wheels associated with and supporting each base, at least one of said wheels on each base being removably mounted on said base, and means associated with said removable wheels for connecting said bases together to form an integral unit having a plurality of lifting heads.
  • a pair of individually operable jacks each comprising a lifting head, a base portion, atleast three leg elements secured to each base portion, rotatable means associated with each leg element and supporting said leg element, a second means associated with each base portion for elevating one of said lifting heads, and a third means for selectively connecting a leg element of one of said jacks to a leg element of the other of said jacks, said third means being operable to connect said leg elements upon removal of the rotatable means associated with said connected leg 'elements.
  • An independently operable jack comprising a lifting head, a. base portion, means to elevate said lifting head relative to said base portion, at least three leg elements extending substantially horizontally from said base portion, at least one of said leg elements being provided with a boit receiving element, a plurality of casters each of which supports one of said leg elements, a plurality of bolts securing one of said casters to one of said leg elements by means of said bolt receiving element, whereby said bolts and said caster may be selectively removed and the bolt receiving element of a similar jack bolted to said element to operably unite said jacks.
  • a pair of independently operable jacks each comprising a lifting head, a base portion, a plurality of leg elements secured to each base portion, rotatable means associated with each leg element and supporting said leg element, a sec- 0nd means associated with each base portion for elevating one of said lifting heads, one of the leg elements of each of said jacks being provided with a vertical flange, said flanges being adapted to be selectively coupled together to operably unite said jacks.
  • a pair of independently operable jacks each comprising a lifting head, a base portion, a plurality of leg elements secured to each base portion, rotatable means associated with each leg element and supporting said leg element, a second means associated with each base portion for elevating one of said lifting heads, one of the leg elements of each of said jacks being provided with bolt receiving openings by means of which said leg elements and said jacks may be operably united.
  • a portable hydraulic jack comprising a base operable to support said jack and having a fluid reservoir formed therein, an elevatable column carried by said base, manually operable hydraulic means operatively connected to said reservoir and operable to selectively elevate and lower said column relative to said base, a fixture associated with said base and operable to cooperate with a corresponding fixture on another similar jack REFERENCES CITED

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  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Geology (AREA)
  • Mechanical Engineering (AREA)
  • Structural Engineering (AREA)
  • Accommodation For Nursing Or Treatment Tables (AREA)

Description

Nov. 14, 1950 P. E. WALLACE 2,530,138
JACK
Filed Nov. 22, 1946 2 Sheets-Sheet 1 INVENTOR.
1/] Eugene MIL-lee.
Nov. 14, 1950 P. E. WALLACE 2,530,138
JACK
Filed Nov. 22, 1946 2 Sheets-Sheet 2 IN VEN TOR.
Paz/Z 11 27]: n/allace. BY
XMMIQM to .var ious loads and various shapes. sembly of. a plurality of jacksinto a working unit .permits the load carrying capacity of the unit 1 jack. can be made.
Patented Nov. 14, 1950 1 um'rao STATE-S PATENT OFFICE 2,530 138 JACK Paul Eugene Wallace Omaha, N ebl. Application- November 22, 134 Serial N0. 711,648 6 'fllaims. (c1. gsu gs) This invention relates to.ja cks and more ,par-
' .ticularly to jacks so constructed that a plurality .thefeofmay. bejoined to provide a unit having apl'urality' of lifting heads.
The device .to .be described herein is particularly adaptedfor. usein motor vehiclerepair.
Inthe disassembly of motor vehicle components such as the. engine itjisdesirable to elevate the T'Vehicle and thenv lower the 'heavy component rather than-raise the heavy component .by chain fallsetc.
My novel jack is'especially adapted for re1atively high work and it is particularly adaptable The asto. be increased and permits the lifting heads to ..be,so 'assembled that they are able .to contact the object to be lifted at advantageous points.
, It, is .to .beunderstood that although reference a has'been, made to the'use of this 'jack in the servicing of automobiles that the invention i not so' limited and that other applications for. the
In ,thedrawings: Figure 1 is an elevation of thejack which is partly in .section.
Eigure 2 is a sidegelevation of Figure 1. FigureS is a. section on the line 3 3 of Figure 2.
Figure 4 is an elevation ofadouble unit which consists of the assemblygof two 1 of the jacks shown in Figures 1 through 3.
' Figure 5 isasection on the line 55 of Fig- In Figure 1 an individual jack I0 is illustrated.
The jack comprises a housing H and stationary tubular column 12., The column "ll-is retained .in a vertical position 'andhas its lower en'd sealed by a plu l3 and itsupper endsealed by bearing '14. in the co1umn.l2 and has apiston rod IS secured tothe upper portion .ofthe piston. The, bearing It has an opening which the piston rod pene- A hydraulic piston. is slidablymounted trates. A suitable lifting head .11 provided with clamping screwsis secured to the upper end of v the piston rod H5.
The housing II is hollow and supports aplurality (preferably-three) of horizontal legs .58.
The legs 58 are hollow and form an oil reservoir l8- in .combinationwith the hollow interior of the housing. A threaded plug 19 in housing ll provides an inlet by which oil may be added to the. reservoir. The column 12 is supported in .lor using;ll at two points.- It contacts the lower and provides a fulcrum for a laterallyfeiitehding handle;ZB which isi pivotally mounted on collar 21 atZ Q. connecting rod: 1s rotatablycon- .,nected to an intermediate portionof 'the'h andle at 3l. 1 Manual-operation of the handle reciprocates the piston- 24 through the connectingrod'iill and piston rod 2 6. I A tool tray 32 may be mounted on the column I2'if desired. The'trayis preferfairly rotatable relative -to the column.
' suitable valving is provided so 'that reciprocation ofithe piston 24" by operation-of handle-:28
' will effect anelevation of piston l 5, -piston rod .16 and lifting head 11. The screW- ZOfe'Xtends through plugl3 and provides'an abutment that engagesa protrusion on piston l5 illustrated as screw; 33 I to assure that a pressure chamber 34 is provided below the piston l5. Anorifice 35 is aligned withga fluid passagetdprovided in the a base of housing'll. A similar passage 3! is pr'ovided in the base of supplemen talhousing Z2 'and alignedwith passage 36. Apassage 38 coni1'ects LthGJIOWGI; portion of cylinder 23 with passage 31. A one way check valve 39 permits fluid to} travel spat a 8 .tof' a s si i s e e ment of fluidin the opposite direction. An orifice '40 conn ects'fcharnber- 18 with the lower portion of cylinder "23." "A one *way check valve 4| permits fluid to travel from chamber "IE to cylinder 23 butprevents the return'movement-thereof. Qrifices 42 and l3 are fprovided in the upper portion of the wall of cylinder 23 and connect the y nd r withthes ambrs J T @93 respectively,
so that air pressure in these compartments is equalized. A bleedhole 14 is provided inthe upp r mr ig tt .q l imnjl so h ther cape from ,or ,enter thecolumn l2 as" the 'piston :m th r1i In operation, when the handle 28 is raised the piston 24 is raised. The low pressure created below j piston 2: by the upward movement thereof causes joil to'leave chamber 58 and enter cylinder 23 t hr ough orifice M past valve 4!, As the and cylinder into chambers and H3.
, thereby causes the piston to lower. may be arrested at any time by permitting spring leg 58.
. to the housing 5|.
handle 28 and piston 24 are lowered valve 4| closes and valve 39 opens permitting oil to travel from cylinder 23, through orifice 38, past valve 39 into passages 31, 36, and into the pressure chamber below piston l5. The entrance of this oil forces piston l5 upward. When the piston 24 has completed its downward stroke and begins to rise the pressure of the piston l5 on the oil below it closes valve 39. The oil trapped below .piston l5 by the closed valve 39 supports the piston l5 until the next successive downward motion of piston 24 again raises piston [5.
A valve controlled bleed back to return oil from the chamber below piston IE to the chamber I8 is provided as a means of lowering the piston l5 and lifting head ll. A passage connected to passage 31 below valve 39 leads to a small cylinder 5|. Cylinder 5| is vertically disposed in the base of supplemental housing 22 and the upper end of cylinder 5| opens into chamber l8. A small piston 52 is slidably mounted in cylinder 5|.
A piston rod 53 extends upwardly from piston 52 l and projects through an aligned opening in the upper portion of supplemental housing 22. The piston rod 53 is provided with spaced abutments 54 and 55 which are adapted to engage the upper and lower portions, respectively, of the supplemental housing 22 and limit movement of the piston rod 53. The abutments are so spaced relative to rod 53 and housing 22 that limited movement of the piston 52 is permitted. A spring 55 ton 52 exposes the upper portion of cylinder 5| to orifice 50. Oil retained under pressure below piston l5 then flows through passages 35, 36, 50 The weight of piston l5 and any load supported This motion 56 to return valve 52 to its upper position blocking passage 50.
Legs 58 extend laterally from the housing Each individual jack has been illustrated as provided with 3 legs 58 although'more legs could be provided if desired. Each leg is supported by a caster 60. Legs 58 in Figure 3 illustrate one means by which a caster 6|) may be secured to a Each caster 60 comprises a housing 6| having a vertical opening 62 therein. A wheel 63 and a bifurcated element 64 are adapted to rotatably support said wheel. The bifurcated element 64 has a vertical shaft portion 65 which is rotatably mounted in the opening 62 of housing 6|. The constructionillustrated on legs 53' of Figure 3 shows a collar 66 which is secured The collar 66 circumscribes the end portion of leg 58 and is secured thereto as by welding. A suitable plug 61 covers the end of leg 58' so that oil will be retained in the leg. This caster construction is of a permanent nature and does not admit of the removal of the caster.
A second construction of the caster and leg is designed for use on one or more legs to facilitate the joinder of two or more individual jacks.
.In this construction the end portion of the leg 58 isprovided with a vertical flange 10. The housing 6| of the caster is provided with a cooperating vertical plate II which has an external contour that is generally similar to the external contour of the flange 10. The flange 10 and vertical When piston rod 53 is bolted together.
plate 1| are provided with aligned openings (not shown) by means of which bolts 12 may be used to secure the plate H to the flange 10. Corresponding legs of individual jacks may be joined as illustrated in Figures 4 and 5 by removing the bolts 12 and the casters 60 and placing the flanges 10 of the corresponding legs in contact. The bolts 12 may then be inserted and the flanges ill of individual jacks A section of pipe I3 illustrated in dotted lines in Figure 4 may be inserted during assembly to strengthen the joint if desired. A drain plug 75 may be provided in the bottom of housin M if desired so that oil may be drained from the reservoir l8 preparatory to the joinder of individual jacks and so that removal of a caster will not cause a loss of oil. If desired the end of leg 58 may be permanently sealed to prevent the loss of oil although such a construction would not admit of the use of pipe 13.
If one leg of each jack is provided with a removable caster as illustrated in the drawings then two jacks may be joined. If more than one leg of each jack is provided with a removable caster then an unlimited number of jacks may be joined. The joinder of a plurality of jacks permits the total weight of the load to be distributed between the jacks. Individual manipulation of joined jacks permits the lifting heads to be adjusted so that they will engage the particular contour of the object to be lifted or lowered to their best advantage.
Iclaim:
1. A plurality of independently operable jacks each comprising a lifting head, a base, hydraulic means associated with said bases for elevating said lifting heads, a plurality of wheels associated with and supporting each base, at least one of said wheels on each base being removably mounted on said base, and means associated with said removable wheels for connecting said bases together to form an integral unit having a plurality of lifting heads.
2. A pair of individually operable jacks each comprising a lifting head, a base portion, atleast three leg elements secured to each base portion, rotatable means associated with each leg element and supporting said leg element, a second means associated with each base portion for elevating one of said lifting heads, and a third means for selectively connecting a leg element of one of said jacks to a leg element of the other of said jacks, said third means being operable to connect said leg elements upon removal of the rotatable means associated with said connected leg 'elements.
3. An independently operable jack comprising a lifting head, a. base portion, means to elevate said lifting head relative to said base portion, at least three leg elements extending substantially horizontally from said base portion, at least one of said leg elements being provided with a boit receiving element, a plurality of casters each of which supports one of said leg elements, a plurality of bolts securing one of said casters to one of said leg elements by means of said bolt receiving element, whereby said bolts and said caster may be selectively removed and the bolt receiving element of a similar jack bolted to said element to operably unite said jacks.
4. A pair of independently operable jacks each comprising a lifting head, a base portion, a plurality of leg elements secured to each base portion, rotatable means associated with each leg element and supporting said leg element, a sec- 0nd means associated with each base portion for elevating one of said lifting heads, one of the leg elements of each of said jacks being provided with a vertical flange, said flanges being adapted to be selectively coupled together to operably unite said jacks.
5. A pair of independently operable jacks each comprising a lifting head, a base portion, a plurality of leg elements secured to each base portion, rotatable means associated with each leg element and supporting said leg element, a second means associated with each base portion for elevating one of said lifting heads, one of the leg elements of each of said jacks being provided with bolt receiving openings by means of which said leg elements and said jacks may be operably united.
6. A portable hydraulic jack comprising a base operable to support said jack and having a fluid reservoir formed therein, an elevatable column carried by said base, manually operable hydraulic means operatively connected to said reservoir and operable to selectively elevate and lower said column relative to said base, a fixture associated with said base and operable to cooperate with a corresponding fixture on another similar jack REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 1,046,207 Lynt Dec. 3, 1912 1,614,697 Snook Jan, 18, 1927 1,907,024 Willard et al. May 2, 1933 FOREIGN PATENTS Number Country Date 451,868 France Feb. 22, 1913
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2695759A (en) * 1951-02-13 1954-11-30 William M Crosslin Lifting device for fiberboard and the like having a braced base supported upright
US2840345A (en) * 1953-06-24 1958-06-24 William A Atkinson Mobile handling rack for differential gear unit
US3084764A (en) * 1961-08-07 1963-04-09 Duffey Billy Joe Tool tray for vehicle grease racks
US4645181A (en) * 1985-09-30 1987-02-24 Schapansky Lloyd D High performance air jack

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1046207A (en) * 1912-06-14 1912-12-03 Richard W Gaffney Hydraulic jack.
FR451868A (en) * 1912-12-13 1913-04-30 Charles Jean Boisselot Adjustable rolling jack with three or four rollers forming a fulcrum
US1614697A (en) * 1925-03-24 1927-01-18 Percy G Cumming Combination crane and motor stand
US1907024A (en) * 1929-12-13 1933-05-02 Willard Portable hoist

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1046207A (en) * 1912-06-14 1912-12-03 Richard W Gaffney Hydraulic jack.
FR451868A (en) * 1912-12-13 1913-04-30 Charles Jean Boisselot Adjustable rolling jack with three or four rollers forming a fulcrum
US1614697A (en) * 1925-03-24 1927-01-18 Percy G Cumming Combination crane and motor stand
US1907024A (en) * 1929-12-13 1933-05-02 Willard Portable hoist

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2695759A (en) * 1951-02-13 1954-11-30 William M Crosslin Lifting device for fiberboard and the like having a braced base supported upright
US2840345A (en) * 1953-06-24 1958-06-24 William A Atkinson Mobile handling rack for differential gear unit
US3084764A (en) * 1961-08-07 1963-04-09 Duffey Billy Joe Tool tray for vehicle grease racks
US4645181A (en) * 1985-09-30 1987-02-24 Schapansky Lloyd D High performance air jack

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