US3536355A - Surgical chair or the like - Google Patents

Surgical chair or the like Download PDF

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US3536355A
US3536355A US739334A US3536355DA US3536355A US 3536355 A US3536355 A US 3536355A US 739334 A US739334 A US 739334A US 3536355D A US3536355D A US 3536355DA US 3536355 A US3536355 A US 3536355A
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seat
leg rest
rest
chair
journalled
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US739334A
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Gunnar Ingemar Sigvard Osbeck
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    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61GTRANSPORT, PERSONAL CONVEYANCES, OR ACCOMMODATION SPECIALLY ADAPTED FOR PATIENTS OR DISABLED PERSONS; OPERATING TABLES OR CHAIRS; CHAIRS FOR DENTISTRY; FUNERAL DEVICES
    • A61G15/00Operating chairs; Dental chairs; Accessories specially adapted therefor, e.g. work stands
    • A61G15/02Chairs with means to adjust position of patient; Controls therefor

Definitions

  • the present invention has reference to surgical chairs, in particular chairs for dental treatment of patients.
  • the chair is of the kind having a vertically displaceable post with its upper end shaped as a head carrying a seat, a back rest being swingably attached to the rear border of said seat and a leg rest attached to the front border of said seat.
  • the leg rest is via links journalled to the arm rests on the back rest such that at a folding rearwardly and downwardly of the back rest the leg rest is folded frontwards and upwards.
  • the object of the invention is to provide a sitting 0r lying position of the patient suitable for the treatment of the same and preventing the patient from sliding in forward direction during the treatment by the swinging upwards of the seat. This has been achieved thereby that the seat is swingable in relation to the post head about a horizontal shaft which may comprise a pair of bolts and providing the head with a forwardly directed arm and providing said two portions with sliding guides for engagement with each other.
  • the present invention relates to surgical chairs in particular for dental treatment of patients, said chairs having a vertically displaceable post the upper end of which being shaped as a head carrying a seat, a back rest being attached in a swingable way to the back border and a leg rest being swingably attached to the front edge of said seat.
  • the leg rest is via links journalled to arm rests journalled to the back rest in such a way that at the folding rearwards and downwards of the back rest the leg rest is folded frontwards and upwards.
  • the seat is swingable about a horizontal shaft, e.g. two coaxial bolts, in relation to the post head, that the latter is provided with an elongation portion extending in the forward direction and the leg rest portion is provided with an arm directed rearwards, said two portions being provided with Sliding guides engaging each other. Due to the sliding guides arranged in the indicated way the seat on the chair will at the rearwards folding of the back rest and the frontwards folding of the leg rest caused thereby be swung about said horizontal shaft in such a way that the seat will be lifted to a small extent at its front border. It is hereby obtained a sitting or lying position of the patient suitable for the treatment of the same. The patient is prevented from sliding in frontward direction during the treatment by this swinging upwards of the seat.
  • a horizontal shaft e.g. two coaxial bolts
  • the elongation of the post head is adjustable to different inclination positions in relation to the post in a vertical plane through the longitudinal plane of the same. It is hereby rendered possible to choose the correct inclination of the seat at a back rest being folded up or folded down.
  • FIG. 1 shows a vertical longitudinal section through a dentists chair according to the invention with its back rest folded up
  • FIG. 2 is a side elevation of the chair with the back rest folded down to reclining position
  • FIG. 3 is a plan View of the chair with upholstery and covering removed for sake of clearness
  • FIG. 4 shows on an enlarged scale a side elevation of the seat and the leg rest with associated parts in sitting position
  • FIG. 5 is a similar side elevation with the seat and the leg rest in lying position
  • FIGS. 6 and 7 are views corresponding to FIGS. 4 and 5 but with the seat adjusted such that its front border is lowered
  • FIG. 8 shows a section on the line VIII-VIII in FIG. 4,
  • FIG. 9 shows a vertical section on the line IX-IX in FIG. 5,
  • FIG. 10 shows a vertical section on the line X-X in FIG. 6,
  • FIG. 11 shows a vertical section on the line XI-XI in FIG. 7.
  • the dentists chair shown on the drawings comprises as main portions a seat 1, a back rest 2 journalled to said seat at the rear border of the same and a leg rest 3 journalled to the seat at the front end of the same, a foot rest 4 being connected to the leg support.
  • the hinge or pivot between the seat 1 and the back rest 2 has been denoted by reference number 5, the pivot between the seat and the leg rest 3 by reference number 6 and the pivot between the leg rest and the foot rest 4 by reference number 7.
  • the supporting frame 8 of the seat 1 is by means of two horizontal coaxial trunnions 9 swingable about the upper end, shaped as a head 10, of a vertically displaceable post 11.
  • Two two-armed levers 13 are journalled about horizontal, coaxial bolts 12 on the supporting frame 8, these levers 13 being with the upper end journalled to the front end of the arm rests 14 which with the rear ends are journalled to the back rest 2.
  • the lower end 15 of the levers 13 are via a link 16 journalled to the leg rest 3. Due to these pivots there is obtained at the folding frontwards and upwards of the leg rest 3 a simultaneous folding rearwards and downwards of the back rest 2.
  • the head 10 is shaped with a forwards directed portion 17, a U-formed elongation portion 20 being at this portion 17 journalled about two horizontal coaxial pins 18 with the rearwards directed branches 19.
  • the elongation portion 20 is provided with a forwards directed guide 21 in which there runs a roller 22, on the free end of a rearwards directed arm 23 on the leg rest 3.
  • the portion 17 directed in frontward direction on the head 10 is provided with a downwards directed nose 24, an internally threaded nut 26 being rotatable on said nose 24 about horizontal coaxial pins 25 and a screw spindle 27 extends through said nut 26.
  • the screw spindle 27 is driven by means of a motor 28, e.g. a hydraulic motor, the stand 29 of which is pivotally connected to the leg rest 3 by means of a bolt 30.
  • the U-shaped elongation portion 20 is made adjustable to different positions of inclination about the pins 18. As shown in FIGS. 8, 9, 10, and 11 the elongation portion 20 is adjustable to different positions of inclination by means of a set screw 33 and a locking screw 32. The higher the guide 21 will be at this adjustment, the higher will be the front border 31 of the seat 1.
  • the guide 21 may be arranged on the rearwards directed arm 23 on the leg rest 3 and the roller 22 may be arranged on the front end of the U-shaped elongation portion 20. Further, the roller 22 may be replaced by a stationary pin or slide piece.
  • a chair adapted for dental treatment of patients said chair having a vertically adjustable post the upper end of which is shaped to form a head carrying a seat, a back rest journalled to the rear border of said seat and a leg rest journalled to the front border of said seat, said leg rest being, by means of links, pivotally connected to arm rests journalled to the back rest in such a way that at a folding rearwards and downwards of the back rest, the leg rest is folded in forward and upward direction, a seat swingable in relation to a post head about a horizontal shaft, wherein the improvement comprises a head with a forwardly directed elongation portion and a leg rest with a rearwardly directed arrn portion, these two portions being provided with sliding means for cooperating with each other such that at a folding up of the leg 4 rest the adjacent ends of the seat. and the leg rest are lifted.
  • the sliding means comprises a pin-like means on the inner end of the arm on the leg rest and a forwardly directed guide on the front end of the elongation portion of the post head, said pinlike means being adapted to slide in said forwardly directed guide at the folding of the leg rest,
  • a chair as claimed in claim 1 in which the sliding means comprises a pinlike means arranged at the front end of the elongation portion of the post head and a rearwards directed guide arranged at the rear end of the rearwards directed arm of the leg rest.
  • a chair as claimed in claim 1, wherein the improvement comprises making the elongation portion of the post head adjustable to different inclination positions in relation to the post in a vertical plane through the longitudinal axis of said post.
  • a chair as claimed in claim 4, wherein the improvement comprises journalling the rear end of the elongation portion about a horizontal shaft and through the post head and making it lockable to the latter in the desired inclination position.

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  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Accommodation For Nursing Or Treatment Tables (AREA)

Description

6 Sheets-Sheet 1 Filed June `24, 1968 Jlfll GUNNAR l. S. OSBECK INVENTOR Oct. 271, 1970 G. s. osBEcK 3,536,355
. SURGICAL CHAIR OR THE LIKE Filed June 24, 196s e sheets-sheet z GUNNAR |.'s. oslEcK 'INVENTOR BYmPfTm/,MJM
0f- 27 1970 G. l. s.osBEcK 3,536,355
SURGICAL CHAIR 0R THE LIKE Filed. June 24, 196s' v e sheets-sheet s Fig. 4
GUNNAR I. S. OSBECK NVENTOR O 27 1970 G. s. osBEcK I 3,536,355
SURGICAL cima on THE LIKE Filed June 24, 1968 s sheets-sheet U5 LIV* 2X l am a N/ I l V m j N N l GUNNAR l. S. OSBECK v NVENTOR Bymumpgj,
G. s. osBEcK SURGICAL CHAIR R THE LIKE 6 Sheets-Sheet `"l Filed June 24, lee
GUNNAR l. S. OSBECK Oct. 27, 1970 G. s. osBEcK SURGICAL CHAIR OR THE LIKE 6 Sheets-Sheet 6 Filed June 24, 1968 QN om GUNNAR I. YS. OSBECK /N VEN mn Bv wir mtt United States Patent O 3,536,355 SURGICAL CHAIR R THE LIKE Gunnar Ingemar Sigvard Osbeck, Vasagatan 35, Goteborg C, Sweden Filed June 24, 1968, Ser. No. 739,334 Int. Cl. A47c 1/24 U.S. Cl. 297-71 5 Claims ABSTRACT 0F THE DISCLOSURE The present invention has reference to surgical chairs, in particular chairs for dental treatment of patients. The chair is of the kind having a vertically displaceable post with its upper end shaped as a head carrying a seat, a back rest being swingably attached to the rear border of said seat and a leg rest attached to the front border of said seat. The leg rest is via links journalled to the arm rests on the back rest such that at a folding rearwardly and downwardly of the back rest the leg rest is folded frontwards and upwards. The object of the invention is to provide a sitting 0r lying position of the patient suitable for the treatment of the same and preventing the patient from sliding in forward direction during the treatment by the swinging upwards of the seat. This has been achieved thereby that the seat is swingable in relation to the post head about a horizontal shaft which may comprise a pair of bolts and providing the head with a forwardly directed arm and providing said two portions with sliding guides for engagement with each other.
The present invention relates to surgical chairs in particular for dental treatment of patients, said chairs having a vertically displaceable post the upper end of which being shaped as a head carrying a seat, a back rest being attached in a swingable way to the back border and a leg rest being swingably attached to the front edge of said seat. The leg rest is via links journalled to arm rests journalled to the back rest in such a way that at the folding rearwards and downwards of the back rest the leg rest is folded frontwards and upwards.
The main feature of the invention is tobe seen therein that the seat is swingable about a horizontal shaft, e.g. two coaxial bolts, in relation to the post head, that the latter is provided with an elongation portion extending in the forward direction and the leg rest portion is provided with an arm directed rearwards, said two portions being provided with Sliding guides engaging each other. Due to the sliding guides arranged in the indicated way the seat on the chair will at the rearwards folding of the back rest and the frontwards folding of the leg rest caused thereby be swung about said horizontal shaft in such a way that the seat will be lifted to a small extent at its front border. It is hereby obtained a sitting or lying position of the patient suitable for the treatment of the same. The patient is prevented from sliding in frontward direction during the treatment by this swinging upwards of the seat.
According to a further development of the invention, the elongation of the post head is adjustable to different inclination positions in relation to the post in a vertical plane through the longitudinal plane of the same. It is hereby rendered possible to choose the correct inclination of the seat at a back rest being folded up or folded down.
Further characteristics of the invention will be obvious from the following description description with reference to the drawings.
In the drawings:
FIG. 1 shows a vertical longitudinal section through a dentists chair according to the invention with its back rest folded up,
3,536,355 Patented Oct. 27, 1970 ICC FIG. 2 is a side elevation of the chair with the back rest folded down to reclining position,
FIG. 3 is a plan View of the chair with upholstery and covering removed for sake of clearness,
FIG. 4 shows on an enlarged scale a side elevation of the seat and the leg rest with associated parts in sitting position,
FIG. 5 is a similar side elevation with the seat and the leg rest in lying position,
FIGS. 6 and 7 are views corresponding to FIGS. 4 and 5 but with the seat adjusted such that its front border is lowered,
FIG. 8 shows a section on the line VIII-VIII in FIG. 4,
FIG. 9 shows a vertical section on the line IX-IX in FIG. 5,
FIG. 10 shows a vertical section on the line X-X in FIG. 6, and
FIG. 11 shows a vertical section on the line XI-XI in FIG. 7.
The dentists chair shown on the drawings comprises as main portions a seat 1, a back rest 2 journalled to said seat at the rear border of the same and a leg rest 3 journalled to the seat at the front end of the same, a foot rest 4 being connected to the leg support. The hinge or pivot between the seat 1 and the back rest 2 has been denoted by reference number 5, the pivot between the seat and the leg rest 3 by reference number 6 and the pivot between the leg rest and the foot rest 4 by reference number 7. The supporting frame 8 of the seat 1 is by means of two horizontal coaxial trunnions 9 swingable about the upper end, shaped as a head 10, of a vertically displaceable post 11. Two two-armed levers 13 are journalled about horizontal, coaxial bolts 12 on the supporting frame 8, these levers 13 being with the upper end journalled to the front end of the arm rests 14 which with the rear ends are journalled to the back rest 2. The lower end 15 of the levers 13 are via a link 16 journalled to the leg rest 3. Due to these pivots there is obtained at the folding frontwards and upwards of the leg rest 3 a simultaneous folding rearwards and downwards of the back rest 2.
The head 10 is shaped with a forwards directed portion 17, a U-formed elongation portion 20 being at this portion 17 journalled about two horizontal coaxial pins 18 with the rearwards directed branches 19. The elongation portion 20 is provided with a forwards directed guide 21 in which there runs a roller 22, on the free end of a rearwards directed arm 23 on the leg rest 3.
The portion 17 directed in frontward direction on the head 10 is provided with a downwards directed nose 24, an internally threaded nut 26 being rotatable on said nose 24 about horizontal coaxial pins 25 and a screw spindle 27 extends through said nut 26. The screw spindle 27 is driven by means of a motor 28, e.g. a hydraulic motor, the stand 29 of which is pivotally connected to the leg rest 3 by means of a bolt 30.
When the motor 28 is started and the screw spindle 27 as a result thereof is screwed in frontward direction in relation to the nut 26, the leg rest 3 is folded in frontward and upward direction and the back rest 2 will thereat via the links 16, the levers 13 and the arm rests 14 be folded rearwardly and downwardly. When the leg rest 3 is folded in frontwards direction about the pivot 6, there is obtained also a turning movement about the roller 22 which at the same time slides in forward direction in the guide 21. This causes that the pivot 6 and thus also the front border 31 of the seat 1 are lifted. When by means of a reversal of the movement direction of the motor 28 the spindle 27 is driven in the opposite direction, the leg rest 3 is swung rearwards and downwards at a simultaneous raising of the back rest 2 and at the same time the roller 22 will slide rearwards in the guide 21 which causes the pivot 6 and the front border 31 of the seat 1 again to be lowered.
So as to obtain an adjustment of the rearwards inclination of the seat 1 as desired, the U-shaped elongation portion 20 is made adjustable to different positions of inclination about the pins 18. As shown in FIGS. 8, 9, 10, and 11 the elongation portion 20 is adjustable to different positions of inclination by means of a set screw 33 and a locking screw 32. The higher the guide 21 will be at this adjustment, the higher will be the front border 31 of the seat 1.
The invention has been described in the aforegoing for purposes of illustration only and is not intended to be limited by this description or otherwise except as dened in the appended claims. Thus, the different portions of the dentists chair may be constructively modified in many ways without departure from the inventive idea. Thus, the guide 21 may be arranged on the rearwards directed arm 23 on the leg rest 3 and the roller 22 may be arranged on the front end of the U-shaped elongation portion 20. Further, the roller 22 may be replaced by a stationary pin or slide piece.
What I claim is:
1. A chair adapted for dental treatment of patients, said chair having a vertically adjustable post the upper end of which is shaped to form a head carrying a seat, a back rest journalled to the rear border of said seat and a leg rest journalled to the front border of said seat, said leg rest being, by means of links, pivotally connected to arm rests journalled to the back rest in such a way that at a folding rearwards and downwards of the back rest, the leg rest is folded in forward and upward direction, a seat swingable in relation to a post head about a horizontal shaft, wherein the improvement comprises a head with a forwardly directed elongation portion and a leg rest with a rearwardly directed arrn portion, these two portions being provided with sliding means for cooperating with each other such that at a folding up of the leg 4 rest the adjacent ends of the seat. and the leg rest are lifted.
2. A chair as claimed in claim 1 in which the sliding means comprises a pin-like means on the inner end of the arm on the leg rest and a forwardly directed guide on the front end of the elongation portion of the post head, said pinlike means being adapted to slide in said forwardly directed guide at the folding of the leg rest,
3. A chair as claimed in claim 1 in which the sliding means comprises a pinlike means arranged at the front end of the elongation portion of the post head and a rearwards directed guide arranged at the rear end of the rearwards directed arm of the leg rest.
4. A chair as claimed in claim 1, wherein the improvement comprises making the elongation portion of the post head adjustable to different inclination positions in relation to the post in a vertical plane through the longitudinal axis of said post.
5. A chair as claimed in claim 4, wherein the improvement comprises journalling the rear end of the elongation portion about a horizontal shaft and through the post head and making it lockable to the latter in the desired inclination position.
References Cited UNITED STATES PATENTS 2,567,222 9/1951 Zorenz 297-79 2,714,922 8/1955 McKibbon et al. 297330 3,053,568 9/1962 Miller 297-78 3,142,509 7/1964 Ehrke et al 297-71 X 3,278,224 10/1966 Dlouhy 297-71 3,330,595 7/1967 Svard 297-71 3,381,997 5/1968 Fritz et al. 297-78 JAMES T. MCCALL, Primary. Examiner U.S. C1. X.R. 297-78
US739334A 1968-06-24 1968-06-24 Surgical chair or the like Expired - Lifetime US3536355A (en)

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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5462388U (en) * 1977-10-12 1979-05-01
FR2418645A1 (en) * 1978-03-03 1979-09-28 Lundin Sven Dentist's chair enabling working from sitting position - pivots from leg supporting region to subject patient to incline no greater than 30 degrees
US4375902A (en) * 1979-08-23 1983-03-08 Royal Dental Manufacturing, Inc. Locking headrest for dental chair
US4492407A (en) * 1982-07-19 1985-01-08 Syntex (U.S.A.) Inc. Patient support and transverse motion linkage therefor
US5678894A (en) * 1996-04-08 1997-10-21 Eley; Christopher D. Dental chair with headrest
US6056363A (en) * 1997-12-29 2000-05-02 Maddox; Lee W. Reclining computer chair apparatus
US20080303329A1 (en) * 2005-08-04 2008-12-11 Heka Dental Aps Chair or a Bed Having a Seat, a Backrest and an Armrest as Well as Use Thereof

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2567222A (en) * 1944-10-11 1951-09-11 Lorenz Anton Reclining article of furniture
US2714922A (en) * 1952-10-17 1955-08-09 Joseph L Mckibban Adjustable reclining chair
US3053568A (en) * 1960-02-05 1962-09-11 Clarence A Silva Chair-bed combination
US3142509A (en) * 1962-07-17 1964-07-28 Robert L Ehrke Adjustable chair
US3278224A (en) * 1964-12-17 1966-10-11 John A Dlouhy Barber chair with adjustable seating angle
US3330595A (en) * 1965-01-25 1967-07-11 Svard Alf Georg Chair, especially dentist's chair
US3381997A (en) * 1966-09-06 1968-05-07 Edward E. Fritz Adjustable chair

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2567222A (en) * 1944-10-11 1951-09-11 Lorenz Anton Reclining article of furniture
US2714922A (en) * 1952-10-17 1955-08-09 Joseph L Mckibban Adjustable reclining chair
US3053568A (en) * 1960-02-05 1962-09-11 Clarence A Silva Chair-bed combination
US3142509A (en) * 1962-07-17 1964-07-28 Robert L Ehrke Adjustable chair
US3278224A (en) * 1964-12-17 1966-10-11 John A Dlouhy Barber chair with adjustable seating angle
US3330595A (en) * 1965-01-25 1967-07-11 Svard Alf Georg Chair, especially dentist's chair
US3381997A (en) * 1966-09-06 1968-05-07 Edward E. Fritz Adjustable chair

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5462388U (en) * 1977-10-12 1979-05-01
FR2418645A1 (en) * 1978-03-03 1979-09-28 Lundin Sven Dentist's chair enabling working from sitting position - pivots from leg supporting region to subject patient to incline no greater than 30 degrees
US4375902A (en) * 1979-08-23 1983-03-08 Royal Dental Manufacturing, Inc. Locking headrest for dental chair
US4492407A (en) * 1982-07-19 1985-01-08 Syntex (U.S.A.) Inc. Patient support and transverse motion linkage therefor
US5678894A (en) * 1996-04-08 1997-10-21 Eley; Christopher D. Dental chair with headrest
US5865505A (en) * 1996-04-08 1999-02-02 Eley; Christopher D. Method of dental treatment
US6056363A (en) * 1997-12-29 2000-05-02 Maddox; Lee W. Reclining computer chair apparatus
US20080303329A1 (en) * 2005-08-04 2008-12-11 Heka Dental Aps Chair or a Bed Having a Seat, a Backrest and an Armrest as Well as Use Thereof
US7618095B2 (en) * 2005-08-04 2009-11-17 Heka Dental A.P.S. Chair or a bed having a seat, a backrest and an armrest as well as use thereof
AU2006275207B2 (en) * 2005-08-04 2011-04-28 Heka Dental Aps A chair or a bed having a seat, a backrest and an armrest as well as use thereof

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