US3472183A - Vertically adjustable table - Google Patents

Vertically adjustable table Download PDF

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US3472183A
US3472183A US682132A US3472183DA US3472183A US 3472183 A US3472183 A US 3472183A US 682132 A US682132 A US 682132A US 3472183D A US3472183D A US 3472183DA US 3472183 A US3472183 A US 3472183A
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bars
cross
pair
bar
vertically adjustable
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US682132A
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Robert Goodman
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    • AHUMAN NECESSITIES
    • A47FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
    • A47BTABLES; DESKS; OFFICE FURNITURE; CABINETS; DRAWERS; GENERAL DETAILS OF FURNITURE
    • A47B9/00Tables with tops of variable height

Definitions

  • One of the sets of cross-bars is operatively connected to an actuating means such as a jack shaft or the like which is, in turn, operated by a drive means which is preferably a reversible motor but which may be any other desired means including even a manually actuated handle.
  • actuating means such as a jack shaft or the like which is, in turn, operated by a drive means which is preferably a reversible motor but which may be any other desired means including even a manually actuated handle.
  • the actuation of one set of cross-bars automatically actuates the other set so that the table top is raised and lowered in a completely horizontal position at all times.
  • This invention relates to an adjustable table, and it particularly relates to a table which may be easily adjusted by infinitely small increments of height.
  • Another object of the present invention is to provide a table of the aforesaid type which is simple in construction, inexpensive to manufacture and easy to operate.
  • FIG. 1 is a perspective view of a table embodying the present invention.
  • FIG. 2 is an enlarged, detailed, perspective view of the operating parts of the table of FIG. 1, with the peripheral skirt deleted to provide a better view.
  • a table generally designated 10, having legs 12 provided with casters 14.
  • the table comprises a table top 16 having a peripheral skirt 17.
  • the table top is mounted on an upper frame consisting of oppositely disposed end bars 18 and 3,472,183 Patented Oct. 14, 1969 20 connected to oppositely disposed side bars 22 and 24.
  • Each end bar 18 and 20 is provided with a dependent flange, as at 26 and 28, respectively.
  • a support frame is provided and comprises oppositely disposed bars 30 and 32 connected by a longitudinal tie bar 34.
  • Each end bar 30 and 32 is provided with legs 12 and casters 14 (as also shown in FIG. 1).
  • the upper and lower frames are connected by a pair of cross-bars 36 and 38 at each end of the table (only one pair of cross-bars being visible since the other pair is hidden behind them).
  • the cross-bars 36 and 38 of each pair are pivotally connected to each other at 40.
  • a coil spring 42 is prefereably provided to interconnect the crossbars 36 and 38 of each pair.
  • the upper end of the cross-bar 36 of eacr pair is pivotally connected, as at 44, to the corresponding flange 26 or 28, while its lower end is provided with a roller 46 movable in a guide channel 48 mounted on the corresponding support bar 30 or 32.
  • the lower end of each cross-bar 38 is pivotally connected a 50 to the corresponding support bar 30 or 32, while its upper end is provided with a roller 52 movable in a guide channel 54 mounted on the corresponding flange 26 or 28.
  • Links 56 pivotally depend from corresponding crossbars 38.
  • a lever 58 is connected at 60 to each of the links 56, these levers being connected to each other by a tie rod 62.
  • the levers 58 are mounted on a rotatable rod 64 journaled at 66 and 68 to the support bars 30 and 32.
  • crank arm 70 Integral with one of the levers 58 is a crank arm 70 to which is connected, as at 72, one end of a shaft 74.
  • the shaft 74 is partially threaded, and the threaded portion extends within an internally threaded jack-screw cylinder 76.
  • the cylinder 76 is connected at 78 to a bracket 80 fixed to the underside of the corresponding support bar 30.
  • a reversible electric motor 82 is operatively connected through gears (not shown) to the shaft 74 to move the shaft in opposite directions relative to the internally threaded cylinder 76.
  • the motor 82 is actuated by a button switch (not shown), or any other desired type of switch, to move the jack-shaft 74 inwardly.
  • a button switch (not shown), or any other desired type of switch, to move the jack-shaft 74 inwardly.
  • This operates the crank arm 70, levers 58 and links 56 to pull the upper ends of the cross-bars 38 downwardly around their pivots 50.
  • the degree of side-angle opening (the angles to the right and left as viewed in FIG. 2) between the bars 36 and 38 is reduced, causing the rollers 52 to come toward the rollers 46.
  • the pivot points 44 and 50 are, in effect, the similar ends of equal and opposite triangles, the pivot points 44 also move toward the pivot points 50 at exactly the same rate of speed.
  • This causes the table top to descend in a continuously level horizontal position.
  • the peripheral skirt may act as a stop for this downward movement or any other desired stop means may be used.
  • the motor is actuated in the reverse direction.
  • An adjustable table comprising an upper frame and a lower frame, a table top mounted on said upper frame, at least two pairs of cross-bars, one at each of two opposite ends of said table, the cross-bars of each pair being pivotally connected to each other intermediate their respective ends, one of the cross-bars of each pair having a roller at its lower end movable in guide means on said lower frame and being pivoted at its upper end to said upper frame, and the other cross-bar of each pair having a roller at its upper end movable in guide means on said upper frame and being pivoted at its lower end to said lower frame, an actuating means, linkage including pivotally connected to each other, said linkage being connected at one end to said actuating means and at the other end to one cross-bar of one pair to move said one cross-bar around its pivoted connection, and connecting means between each pair of cross-bars to provide simultaneous pivotal movement of each pair, said cross-bars constituting both a supporting and a vertical adjusting means for said upper frame.

Description

Oct. 14, 1969 GOODMAN VERTICALLY ADJUSTABLE TABLE Filed Nov. 13, 1967 /NVN7'0R ROBERT GOODMAN A TTOR/VEY R bu mm h. N, NR & an a I? r mm wm mm ,1- mm .ww vm mm La Fe NM .rl UQ WHPG United States Patent 3,472,183 VERTICALLY ADJUSTABLE TABLE Robert Goodman, 5325 Westminster Ave., Philadelphia, Pa. 19131 Continuation-impart of application Ser. No. 579,158, Sept. 13, 1966. This application Nov. 13, 1967, Bar. No. 682,132
Int. Cl. A47b 9/00; A61g 7/00; B66f 3/22 US. Cl. 108-147 4 Claims ABSTRACT OF THE DISCLOSURE An adustable table comprising a support frame upon which a table top is vertically adjustable in infinite increments of vertical positions. The adjustment is effected by pivotally interconnected cross-bars at opposite ends of the table. These cross-bars serve both to support the table top and to adjust it vertically. They also automatically retain the table top in each vertical position. One of the sets of cross-bars is operatively connected to an actuating means such as a jack shaft or the like which is, in turn, operated by a drive means which is preferably a reversible motor but which may be any other desired means including even a manually actuated handle. The actuation of one set of cross-bars automatically actuates the other set so that the table top is raised and lowered in a completely horizontal position at all times.
This invention relates to an adjustable table, and it particularly relates to a table which may be easily adjusted by infinitely small increments of height.
This is a continuation-in-part of copending application Ser. No. 579,158, filed Sept. 13, 1966.
It is often necessary to provide a table which can be adjusted to almost any desired height within a certain range. This is especially true of tables used by physicians, surgeons and the like either for medical examinations or for surgery. Most such tables used heretofore were of the type which could only be adjusted to specific vertical positions and generally utilized such mechanisms as rack and pinions, pin and slot connections and similar means which could be locked in the positions of adjustment and so hold the table steady. However, with such mechanisms, the table could only be adjusted to a predetermined number of positions, none of which might be exactly right for the particular patient or for the particular situation.
It is, therefore, an object of the present invention to provide a vertically adjustable table which can be adjusted by infinitely small increments and which is, nevertheless, rigidly held in each position of vertical adjustment.
Another object of the present invention is to provide a table of the aforesaid type which is simple in construction, inexpensive to manufacture and easy to operate.
Other objects and many of the attendant advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following description when read in conjunction with the accompanying drawings wherein:
FIG. 1 is a perspective view of a table embodying the present invention.
FIG. 2 is an enlarged, detailed, perspective view of the operating parts of the table of FIG. 1, with the peripheral skirt deleted to provide a better view.
Referring now in greater detail to the figures of the drawings wherein similar reference characters refer to similar parts, there is shown a table, generally designated 10, having legs 12 provided with casters 14.
The table comprises a table top 16 having a peripheral skirt 17. The table top is mounted on an upper frame consisting of oppositely disposed end bars 18 and 3,472,183 Patented Oct. 14, 1969 20 connected to oppositely disposed side bars 22 and 24. Each end bar 18 and 20 is provided with a dependent flange, as at 26 and 28, respectively.
A support frame is provided and comprises oppositely disposed bars 30 and 32 connected by a longitudinal tie bar 34. Each end bar 30 and 32 is provided with legs 12 and casters 14 (as also shown in FIG. 1).
The upper and lower frames are connected by a pair of cross-bars 36 and 38 at each end of the table (only one pair of cross-bars being visible since the other pair is hidden behind them). The cross-bars 36 and 38 of each pair are pivotally connected to each other at 40. A coil spring 42 is prefereably provided to interconnect the crossbars 36 and 38 of each pair.
The upper end of the cross-bar 36 of eacr pair is pivotally connected, as at 44, to the corresponding flange 26 or 28, while its lower end is provided with a roller 46 movable in a guide channel 48 mounted on the corresponding support bar 30 or 32. The lower end of each cross-bar 38 is pivotally connected a 50 to the corresponding support bar 30 or 32, while its upper end is provided with a roller 52 movable in a guide channel 54 mounted on the corresponding flange 26 or 28.
Links 56 pivotally depend from corresponding crossbars 38. A lever 58 is connected at 60 to each of the links 56, these levers being connected to each other by a tie rod 62. The levers 58 are mounted on a rotatable rod 64 journaled at 66 and 68 to the support bars 30 and 32.
Integral with one of the levers 58 is a crank arm 70 to which is connected, as at 72, one end of a shaft 74. The shaft 74 is partially threaded, and the threaded portion extends within an internally threaded jack-screw cylinder 76. The cylinder 76 is connected at 78 to a bracket 80 fixed to the underside of the corresponding support bar 30. A reversible electric motor 82 is operatively connected through gears (not shown) to the shaft 74 to move the shaft in opposite directions relative to the internally threaded cylinder 76.
In operation, when it is desired to move the table top 16 from a higher to a lower position, the motor 82 is actuated by a button switch (not shown), or any other desired type of switch, to move the jack-shaft 74 inwardly. This operates the crank arm 70, levers 58 and links 56 to pull the upper ends of the cross-bars 38 downwardly around their pivots 50. As the bars 38 pivot downwardly, causing the rollers 52 to ride laterally in the guides 54, the degree of side-angle opening (the angles to the right and left as viewed in FIG. 2) between the bars 36 and 38 is reduced, causing the rollers 52 to come toward the rollers 46. As the pivot points 44 and 50 are, in effect, the similar ends of equal and opposite triangles, the pivot points 44 also move toward the pivot points 50 at exactly the same rate of speed. This causes the table top to descend in a continuously level horizontal position. The peripheral skirt may act as a stop for this downward movement or any other desired stop means may be used. When it is desired to raise the table top, the motor is actuated in the reverse direction.
Although a motor is illustrated herein as the drive means, any other desired and feasible type of drive means may be substituted, even a manually actuated handle.
Obviously, many modifications and variations of the present invention are possible in the light of the above teachings.
The invention claimed is:
1. An adjustable table comprising an upper frame and a lower frame, a table top mounted on said upper frame, at least two pairs of cross-bars, one at each of two opposite ends of said table, the cross-bars of each pair being pivotally connected to each other intermediate their respective ends, one of the cross-bars of each pair having a roller at its lower end movable in guide means on said lower frame and being pivoted at its upper end to said upper frame, and the other cross-bar of each pair having a roller at its upper end movable in guide means on said upper frame and being pivoted at its lower end to said lower frame, an actuating means, linkage including pivotally connected to each other, said linkage being connected at one end to said actuating means and at the other end to one cross-bar of one pair to move said one cross-bar around its pivoted connection, and connecting means between each pair of cross-bars to provide simultaneous pivotal movement of each pair, said cross-bars constituting both a supporting and a vertical adjusting means for said upper frame.
2. The table of claim 1 wherein said actuating means comprises a jack-screw assembly.
3. The table of claim 2 wherein said jack-screw assembly is operatively connected to a reversible motor.
4. The table of claim 1 wherein the cross-bars of at least one pair are interconnected by a tension means.
References Cited UNITED STATES PATENTS JAMES T. McCALL,
US. Cl. X.R.
Primary Examiner
US682132A 1967-11-13 1967-11-13 Vertically adjustable table Expired - Lifetime US3472183A (en)

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Cited By (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3760436A (en) * 1971-11-05 1973-09-25 Universal Oil Prod Co Suspension system for vehicle mounted bed
US3883105A (en) * 1974-06-05 1975-05-13 Reizou Matsumoto Load handling equipment
US4071222A (en) * 1975-10-24 1978-01-31 Wright Howard S Lifting platform
US4558648A (en) * 1983-09-20 1985-12-17 Lift-R Technologies, Inc. Energy-recycling scissors lift
US4585212A (en) * 1984-12-07 1986-04-29 International Business Machines Corporation Lift device of the scissor-jack type
US4693660A (en) * 1985-12-24 1987-09-15 Lacroix Lloyd A Scissor lift and transport
US4792272A (en) * 1986-05-23 1988-12-20 Standard Manufacturing Company, Inc. Container handling apparatus
US4890692A (en) * 1988-12-06 1990-01-02 Jlg Industries, Inc. Platform elevating apparatus
US5022105A (en) * 1989-08-04 1991-06-11 Michael Catoe Mobile lift-assisted patient transport device for field use
US5285992A (en) * 1992-07-14 1994-02-15 Brown Ronald G Adjustable step stool
US5305482A (en) * 1991-03-28 1994-04-26 Dewert Antriebs-Und Systemtechnik Gmbh & Co Kg Lifting device
US5774915A (en) * 1995-09-13 1998-07-07 Standex International Patient treatment apparatus
US5802638A (en) * 1993-03-18 1998-09-08 Keymed (Medical & Industrial Equipment) Ltd. Adjustable load supporting apparatus
EP1384697A1 (en) * 2002-07-26 2004-01-28 Hans Balle A/S Scissor lift device
US20040118326A1 (en) * 2002-12-02 2004-06-24 Guy Carpentier Pop-up mechanism to raise the top of pieces of furniture
US20040128766A1 (en) * 2002-10-25 2004-07-08 Brian Freeborn Adjustable bed carriage
ES2264604A1 (en) * 2004-06-03 2007-01-01 Pikolin, S.A. Elevating system for furniture, has fixed frame base and upper movable frame supported by straight and non-straight connecting rods under action of gas pistons
US7533429B2 (en) 1999-12-29 2009-05-19 Hill-Rom Services, Inc. Lift system for hospital bed
US7610637B2 (en) 1999-12-29 2009-11-03 Hill-Rom Services, Inc. Lift system for hospital bed
US7653957B1 (en) * 2008-05-07 2010-02-02 Mark Edward Curtiss Collapseable utility ramp
US20110030136A1 (en) * 2008-04-08 2011-02-10 Ki Jun Kim Bed provided with a bathtub
US8065966B1 (en) * 2009-09-24 2011-11-29 Bauer Products, Inc. Odd link work surface lift
US20130341984A1 (en) * 2012-06-20 2013-12-26 develtex ApS Scissor lift and use of a scissor lift
US9107494B2 (en) * 2013-03-14 2015-08-18 Electrolux Home Products, Inc. Refrigerator with a lift mechanism including at least one pivot arm
US9554644B2 (en) 2012-05-24 2017-01-31 Varidesk, Llc Adjustable desk platform
USD854775S1 (en) * 2017-06-28 2019-07-23 G.S.Ace Industry Co., Ltd. Elevation apparatus for lift table
WO2020231677A1 (en) * 2019-05-13 2020-11-19 Huff Ryan Platform leveling apparatus
US11065777B2 (en) * 2018-10-17 2021-07-20 Alexander Homsky Slicing machine

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2412158A (en) * 1944-02-14 1946-12-03 Heil Co Airplane loading and service vehicle
US2706102A (en) * 1951-06-06 1955-04-12 Anthony L Cresci Lifting mechanism for truck body
US2829863A (en) * 1952-07-23 1958-04-08 Raymond Corp Table of adjustable height
US2977168A (en) * 1958-03-03 1961-03-28 F And F Koenigkramer Company Vertically adjustable safety table for near-counter-balanced supporting of instruments
US3110476A (en) * 1960-03-20 1963-11-12 American Mfg Company Inc Thrust linkage supported tables
US3304609A (en) * 1966-02-16 1967-02-21 Horowitz Norman Dental equipment stand
US3308485A (en) * 1964-12-24 1967-03-14 Nesbit Evans & Company Ltd J Beds

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2412158A (en) * 1944-02-14 1946-12-03 Heil Co Airplane loading and service vehicle
US2706102A (en) * 1951-06-06 1955-04-12 Anthony L Cresci Lifting mechanism for truck body
US2829863A (en) * 1952-07-23 1958-04-08 Raymond Corp Table of adjustable height
US2977168A (en) * 1958-03-03 1961-03-28 F And F Koenigkramer Company Vertically adjustable safety table for near-counter-balanced supporting of instruments
US3110476A (en) * 1960-03-20 1963-11-12 American Mfg Company Inc Thrust linkage supported tables
US3308485A (en) * 1964-12-24 1967-03-14 Nesbit Evans & Company Ltd J Beds
US3304609A (en) * 1966-02-16 1967-02-21 Horowitz Norman Dental equipment stand

Cited By (35)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3760436A (en) * 1971-11-05 1973-09-25 Universal Oil Prod Co Suspension system for vehicle mounted bed
US3883105A (en) * 1974-06-05 1975-05-13 Reizou Matsumoto Load handling equipment
US4071222A (en) * 1975-10-24 1978-01-31 Wright Howard S Lifting platform
US4558648A (en) * 1983-09-20 1985-12-17 Lift-R Technologies, Inc. Energy-recycling scissors lift
US4585212A (en) * 1984-12-07 1986-04-29 International Business Machines Corporation Lift device of the scissor-jack type
US4693660A (en) * 1985-12-24 1987-09-15 Lacroix Lloyd A Scissor lift and transport
US4792272A (en) * 1986-05-23 1988-12-20 Standard Manufacturing Company, Inc. Container handling apparatus
US4890692A (en) * 1988-12-06 1990-01-02 Jlg Industries, Inc. Platform elevating apparatus
US5022105A (en) * 1989-08-04 1991-06-11 Michael Catoe Mobile lift-assisted patient transport device for field use
US5305482A (en) * 1991-03-28 1994-04-26 Dewert Antriebs-Und Systemtechnik Gmbh & Co Kg Lifting device
US5285992A (en) * 1992-07-14 1994-02-15 Brown Ronald G Adjustable step stool
US5802638A (en) * 1993-03-18 1998-09-08 Keymed (Medical & Industrial Equipment) Ltd. Adjustable load supporting apparatus
US5774915A (en) * 1995-09-13 1998-07-07 Standex International Patient treatment apparatus
US10251797B2 (en) 1999-12-29 2019-04-09 Hill-Rom Services, Inc. Hospital bed
US9009893B2 (en) 1999-12-29 2015-04-21 Hill-Rom Services, Inc. Hospital bed
US7533429B2 (en) 1999-12-29 2009-05-19 Hill-Rom Services, Inc. Lift system for hospital bed
US7610637B2 (en) 1999-12-29 2009-11-03 Hill-Rom Services, Inc. Lift system for hospital bed
EP1384697A1 (en) * 2002-07-26 2004-01-28 Hans Balle A/S Scissor lift device
US6941600B2 (en) * 2002-10-25 2005-09-13 M.C. Healthcare Products Inc. Adjustable bed carriage
US20040128766A1 (en) * 2002-10-25 2004-07-08 Brian Freeborn Adjustable bed carriage
US6991199B2 (en) * 2002-12-02 2006-01-31 Guy Carpentier Pop-up mechanism to raise the top of pieces of furniture
US20040118326A1 (en) * 2002-12-02 2004-06-24 Guy Carpentier Pop-up mechanism to raise the top of pieces of furniture
ES2264604A1 (en) * 2004-06-03 2007-01-01 Pikolin, S.A. Elevating system for furniture, has fixed frame base and upper movable frame supported by straight and non-straight connecting rods under action of gas pistons
US20110030136A1 (en) * 2008-04-08 2011-02-10 Ki Jun Kim Bed provided with a bathtub
US7653957B1 (en) * 2008-05-07 2010-02-02 Mark Edward Curtiss Collapseable utility ramp
US8065966B1 (en) * 2009-09-24 2011-11-29 Bauer Products, Inc. Odd link work surface lift
US10413053B2 (en) 2012-05-24 2019-09-17 Varidesk, Llc Adjustable desk platform
US9554644B2 (en) 2012-05-24 2017-01-31 Varidesk, Llc Adjustable desk platform
US9924793B2 (en) 2012-05-24 2018-03-27 Varidesk, Llc Adjustable desk platform
US20130341984A1 (en) * 2012-06-20 2013-12-26 develtex ApS Scissor lift and use of a scissor lift
US8888070B2 (en) * 2012-06-20 2014-11-18 develtex ApS Scissor lift and use of a scissor lift
US9107494B2 (en) * 2013-03-14 2015-08-18 Electrolux Home Products, Inc. Refrigerator with a lift mechanism including at least one pivot arm
USD854775S1 (en) * 2017-06-28 2019-07-23 G.S.Ace Industry Co., Ltd. Elevation apparatus for lift table
US11065777B2 (en) * 2018-10-17 2021-07-20 Alexander Homsky Slicing machine
WO2020231677A1 (en) * 2019-05-13 2020-11-19 Huff Ryan Platform leveling apparatus

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