US3145053A

US3145053A - Stool for dentists

Info

Publication number: US3145053A
Application number: US144862A
Authority: US
Inventors: Elbert O Thompson; Dean H Hale
Original assignee: VACUDENT Manufacturing CO
Current assignee: VACUDENT Manufacturing CO
Priority date: 1961-10-13
Filing date: 1961-10-13
Publication date: 1964-08-18
Anticipated expiration: 1981-08-18
Also published as: SE324219B; DE1429442A1; US3179369A; FR1335964A; GB947849A

Abstract

947,849. Hydraulically adjustable seats. VACUDENT MANUFACTURING CO. Oct. 12, 1962 [Oct. 13, 1961 (2); July 3, 1962], No. 38738/62. Heading B8J. [Also in Division A4] A stool comprises a platform base 13, a seat 10, extendible and retractable post structure 11, 12 rising from the base centrally thereof and supporting the seat 10, power means for extending the post to raise the seat, means such as a valve 34 controlling operation of the power means, and means for actuating the control means, the actuating means having a foot-operated portion 44 at least partially surrounding the post structure 11, 12 above the surface of the base 13. The post structure consists of a post 11 and tube 12 which together form an hydraulic assembly. A sleeve 15 is secured to the upper end of the tube 12. As shown in Fig. 4, the footoperated part of the actuating means consists of a ring 44 encircling the post structure. The actuating means also consists of a lever comprising a pair of rods 45 depending slidably through the base 13 from the ring 44, a bearing ring 47 slidable along the lower end of the post structure (Fig. 5) and a working arm 48 projecting from the ring 47. The arm 48 is secured to another lever arm 49 provided as part of valve 34 and pivoted at 50 to operate a spring-loaded plunger 35. The valve 34 is opened by pressure on the ring 44. This permits entrapped compressed air in a reservoir 32 to expand and force hydraulic fluid from this reservoir 32 into tube 12 to raise the seat 10 when the user takes his weight off the seat. A non-return valve 37 prevents fluid flow in the cylinder-reservoir direction. A bleeder passage 51 provides for gradual return of fluid to the reservoir 32 and thus a gradual lowering of the seat under the weight of the user when pressure is applied to the foot ring 44. The post is made in two parts 11, 11-1 so that the seat 10 can be raised independently of the power system. An abdominal rest 17 is provided which may be adjusted vertically, horizontally and rotatably relatively to the seat 10 by means of members 23, 21 and 29 respectively.

Description

1964 E. o. THOMPSON ETAL 3,145,053

STOOL FOR DENTISTS Filed Oct. 15, 1961 INVENTORS ELBERT 0. THOMPSON DEAN H. HALE fit ATTORNEYS United States Patent 3,145,053 STUGL FOR DENTISTS Elbert 0. Thompson, Salt Lake City, and Dean H. Hale, Logan, Utah, assignors to Vacudent Manufacturing Company, Salt Lake (Iity, Utah, a corporation of Utah Filed Get. 13, 1961, Ser. No. 144,862 4 tjlaims. (Cl. 297--383) This invention relates to seating structures, and particularly to stools for special purposes.

The invention is concerned primarily with providing a stool for dentists and dental assistants to be used while working on or administering to dental patients seated in a dental operating chair, although many other uses are possible.

Dentists and dental assistants normally stand while working on or administering to a patient in the dental chair. However, the necessity of bending over and peering into the mouth of a patient imposes considerable strain on the body and results in fatigue and often in muscular pains of one kind or another.

While seating of the dentist during his work has been proposed heretofore and stools have been provided for this purpose, the needs of a dentist and a dental assistant are such that stools of ordinary construction encumber more than they aid.

Principal objects in the making of the present invention were to provide effective and comfortable support for the waist as the upper trunk of the body is cantilevered forwardly toward the patient from a seated position; to provide this in a manner adaptable to the body charac teristics of various users of the stool, to provide for easily and positively locking adjustable components in their adjusted positions; to enable a short person, usually the dental assistant, to sit comfortably and to maneuver effectively, even though his or her feet do not reach the floor when seated; and to provide all of the above with streamlined and pleasing appearance as well as compactness, ease of handling, and minimum spacial encumbrance.

Features of the invention in the attainment of these objects are the provision of stool structure supporting a seat of circular stool formation, and an abdominal body rest of curved strip formation adapted to be mounted above the seat in an adjustable substantially cantilevered arrangement with respect to a supporting post disposed near the circumference of the seat. The curvature of the body rest largely conforms to that of the stool, and the mounting arrangement is preferably such that the rest may be adjusted more or less inwardly toward the vertical axis of the stool to accommodate thin as well as medium and stout individuals, such body rest retaining much of its cantilever arrangement with respect to the post even in its extreme positions of adjustment so that it will extend across the front of the waist of a person seated on the stool and give effective support when such person leans forwardly to take care of the dental work at hand.

Other features are the provision of a platform-like base affording effective support for the feet, particularly when the user is so short that, when seated, his or her feet do not reach the floor, and the provision for independent swiveling of the seat and body rest relative to each other.

The particular power mechanism and cam locks shown are the sole invention of Dean H. Hale and are separately covered by an application for patent Serial No. 144,980 filed concurrently herewith.

A specific embodiment of the invention representing what is presently regarded as the best mode of carrying out the inventive concepts in actual practice is illustrated in the accompanying drawings.

In the drawings:

FIG. 1 represents an elevational View of the stool looking directly toward the back of the post which supports the body rest;

FIG. 2, a top plan view, with a different adjustment of the body rest being indicated by broken lines;

FIG. 3, a bottom plan view;

FIG. 4, a fragmentary view in vertical section taken on line 44 of FIG. 1 and drawn to a larger scale, showing one of the cam locks in its locked position; and

FIG. 5, a corresponding view, but showing the cam lock in its unlocked position.

Referring to the drawings:

In the form illustrated, the stool comprises a circular seat 10 supported in stool fashion at the upper end of a post 11, which rises centrally from a base 13 and depends centrally from the seat as part of an extendible and retractable hydraulic assembly (not shown) mounted in such base.

Base 13 is platform-like and hollow, being maneuverably supported by casters 14. There must be at least three castors for stability, as is quite apparent, but preferably there are five, so that, regardless of surface irregularities in the floor unevenness, there will always be at least a three-point support for the stool with consequent stability at all times during use. The platform character of this base providing a substantially unbroken expanse of supporting surface coupled with the fact that its diameter significantly exceeds that of the seat 10 so that its periphery extends outwardly beyond the periphery of the seat, enables a person seated on such seat to comfortably and effectively rest his or her feet off the floor when found desirable.

For added strength and to facilitate lubrication, a sleeve 15 extends down to the base 13 as a tube housing, where it is secured as by welding. A ring of oil-impregnated felt (not shown) wipes oil onto the surface of post 11 as it rises and descends relative thereto.

In order to provide support for the trunk of the body of a dentist or dental assistant when working from a seated position and leaning outwardly from the seat 10, an abdominal rest 17 is provided in upwardly spaced relationship with the seat. It is supported in what is essentially cantilever fashion from a post 18, which is preferably a broad and rigid bar or strip of some such material as steel or aluminum rising above the seat near the circumference thereof.

Body rest 17 is of broad strip formation in the sense that it is wide but relatively elongate, so as to provide comfortable and effective support for the body at or near the waist. It and seat 10 are preferably cushioned with foam rubber or the like and upholstered with a washable plastic sheet material.

While in some instances it may be desirable to construct the stool with the body rest permanently fixed to its supporting post, in the illustrated construction rest 17 is adjustably positioned relative to post 18 so as to accommodate thin as well as stout persons. In any event, the rest is largely curved in conformity with the seat and is positioned so that its width extends vertically and so that its length extends horizontally in cantilever fashion from one side of the post.

To enable a person to easily move into and out of position on the seat with respect to the body rest, such body rest preferably has its opposite end portions deviating outwardly from the aforespecified curvature, the end portion 17a nearest the supporting post 18 advantageously being rectilinear or approximately so. Best results are had when the circularly curved intermediate portion of the rest subtends an angle of about For the purpose of adjustment, rest 17 is: provided with a bracket arm 19, which extends from near the middle of such rest backwardly and outwardly along the back of one end portion of the rest, see particularly FIG. 2, and

enemas is firmly secured to post 18 by suitable releasable fastening means, such as a unique cam lock 20 operable by hand lever 21 and constructed as shown in detail in FIGS. 4 and 5. In turn, post 18 is firmly but adjustably secured to the rest of the stool structure by means of a second cam lock 22, FIG. 1, operable by hand lever 23.

While cam lock 22 is illustrated in FIGS. 4 and 5, cam lock 20 is of the same type. As shown, a slotted receptacle 24, FIGS. 4 and 5, defines a throughway for slidably receiving post 18 (bracket arm 19 in the instance of cam lock 20). Extending across the interior of receptacle 24 and journaled in the lateral walls thereof is a cam 25 in the form of a rod whose cross section is circular, except for a sector face 26 which is preferably provided with a continuation in the form of a protuberant lip 27 having a terminal face 27a at substantially right angles thereto merging into the otherwise cylindrical periphery of the rod along a tangent.

The lever arm or operating handle 23 (21 in the instance of cam lock 20) is fixed to one end of the cam rod 25 perpendicularly to the sector face 26 of such rod, so that, when such handle is turned up as shown in FIG. 1 (inwardly in the instance of handle 21 of cam lock 20) a curved portion of such rod exercises cam action against the opposing face of post 11 to frictionally lock it tightly against therewith opposing face portions of receptacle 24.

When it is desired to adjust the height of body rest 17 relative to seat 10, it is only necessary to throw handle 23 downwardly and outwardly to bring sector face 26 into parallel position with the' aforesaid opposing face of post 18, see FIG. 5. Lip 27 prevents over-ride and positively establishes the unlocked position. Likewise with cam lock 20, it is only necessary to turn handle 21 clockwise to a position substantially perpendicular to bracket arm 19 in order to permit positional adjustment of body rest 17 relative to its supporting post 18 and to seat 10.

Receptacle 24 of cam lock '22 is secured, as by welding, to the outer and upwardly turned end of a mounting bar 28, so that its throughway is disposed vertically for slidably receiving post 18, while the receptacle of cam lock 20 is similarly secured to the upper end of post 18 with its throughway disposed horizontally for slidably receiving bracket arm 19.

Mounting bar 28 is secured, as by welding, to the upper end of post 11, and, in order to provide for independent swiveling movement of seat and body rest 17 relative to each other, an anti-friction bearing 29, has its upper race plate secured to the seat, as by bolts, and its lower race plate secured to mounting bar 28 and post 11, as by welding.

The mechanism, indicated 32-34, 37, 41, and 42, FIG. 3, for raising seat 10, and coincidentally, body rest 17, is housed within hollow base 13 and is operated by a foot pedal 31 which projects a convenient distance beyond the outer periphery of the base, see FIGS. 1, 2, and 3, at a location that is preferably diametrically opposite one of the castors 14. In order that the person seated on the stool can easily locate such foot-pedal without looking down, it is preferred to permanently fix such opposite castor against swiveling movement, as by driving a pin (not shown) through the castor shank and its holder.

The height of stool seat 10 is adjusted by pressing footpedal 31. It is not intended that there be a lifting of a person seated on the stool, but, rather, that there be a powered lifting of the stool seat 10 alone, since this is all that is necessary from a practical standpoint. Thus, when the dentists or other person using the stool desires to alter his working position upwardly, he need merely step on the foot-pedal while raising his body. The stool seat will closely follow until the pedal is released, whereupon a sitting position can be resumed without ever having taken eyes or hands from the work in progress.

Whereas there is here illustrated and described a certain preferred construction which we presently regard as the best mode of carrying out our invention, it should be understood that various changes may be made without departing from the inventive concepts particularly pointed out and distinctly claimed herebelow.

We claim:

1. A stool particularly adapted for use by dentists and dental assistants while working on dental patients, comprising, in combination: a maneuverable base structure; a substantially circular seat mounted on said base structure; a supporting post extending upwardly from and in adjacency to the periphery of said seat; means mounting said post for revolution about the periphery of said seat; a trunk rest of strip-like, substantially curved configuration mounted cantilever fashion on said post and having its length extending substantially horizontally therefrom; and means adjustably interconnecting said trunk rest and said post for lateral movement of the former relative to the latter, so that the degree of cantilever extension of said trunk' rest from said post can be adjusted as desired.

2. The stool of claim 1 wherein the means adjustably connecting the trunk rest and the post includes a bracket arm extending from the back of the trunk rest and extending longitudinally along approximately one-half of its length, and locking means for fastening the bracket arm to the post in various positions of adjustment.

3. The stool of claim 1, wherein the base structure is of platform formation extending peripherally outwardly beyond the periphery of the seat and providing a substantially unbroken expanse of supporting surface for the feet of the user, and wherein the seat is supported on said base structure by a center post extending upwardly therefrom.

4. The stool of claim 1, further including means interconnecting the seat and the base structure for rotation of said seat relative to said base.

References Cited in the file of this patent UNITED STATES PATENTS 597,991 Lease Jan. 25, 1898 1,005,542 Harmer Oct. 10, 1911 1,976,449 Lorenz Oct. 9, 1934 2,136,852 Knauth Nov. 15, 1938 2,244,650 Curran June 3, 1941 2,400,630 Cramer May 21, 1946 2,620,863 Cooper 1 Dec. 9, 1952 2,935,120 Naus May 3, 1960 FOREIGN PATENTS 298,795 Great Britain Oct. 18, 1928 880,237 Great Britain Oct. 17, 1958

Claims

1. A STOOL PARTICULARLY ADAPTED FOR USE BY DENTISTS AND DENTAL ASSISTANTS WHILE WORKING ON DENTAL PATIENTS, COMPRISING, IN COMBINATION: A MANEUVERABLE BASE STRUCTURE; A SUBSTANTIALLY CIRCULAR SEAT MOUNTED ON SAID BASE STRUCTURE; A SUPPORTING POST EXTENDING UPWARDLY FROM AND IN ADJACENCY TO THE PERIPHERY OF SAID SEAT; MEANS MOUNTING SAID POST FOR REVOLUTION ABOUT THE PERIPHERY OF SAID SEAT; A TRUNK REST OF STRIP-LIKE, SUBSTANTIALLY CURVED CONFIGURATION MOUNTED CANTILEVER FASHION ON SAID POST AND HAVING ITS LENGTH EXTENDING SUBSTANTIALLY HORIZONTALLY THEREFROM; AND MEANS ADJUSTABLY INTERCONNECTING SAID TRUNK REST AND SAID POST FOR LATERAL MOVEMENT OF THE FORMER RELATIVE TO THE LATTER, SO THAT THE DEGREE OF CANTILEVER EXTENSION OF SAID TRUNK REST FROM SAID POST CAN BE ADJUSTED AS DESIRED.