US2682916A - Medical practice chair with adjustable seat frame - Google Patents

Description

July 6, 1954 MEDICAL PRACTICE CHAIR WITH ADJUSTABLE SEAT FRAME Original Filed July 2, 1946 4 Sheets-Sheet l INVENTOR.

Norma/z .5 la zerbacfi W Hi5 Avior/26y N. E. LAUTERBACH 2,682,916

' y 6, 1954 N. E. LAUTERBACH 2,682,916

MEDICAL PRACTICE CHAIR WITH ADJUSTABLE SEAT FRAME Original Filed July 2, 1946 I 4 Sheets-Sheet 2 INVENTOR. /V0 Mia/1 E. Lauzerbach July 6, 1954 N. E. LAUTERBACH MEDICAL PRACTICE CHAIR WITH ADJUSTABLE SEAT FRAME 4 Sheets-Sheet 5 Original Filed July 2, 1946 Fig, 3

INVENTOR. Norman 5 Lauzerfiaclz W #12: Affomey July 6, 1954 MEDICAL PRACTICE Original Filed N. E. LAUTERBACH CHAIR WITH ADJUSTABLE SEAT FRAME July 2, 1946 4 Sheets-Sheet 4 o ,Q'x N Fa INVENTOR. A orman E. Lauzerbach Hz'; Attorney Patented July 6, 1954 MEDICAL PRACTICE CHAIR WITH ADJUSTABLE SEAT FRAME Norman E. Lauterbach, Newark, N. Y., assignor to Ritter Company, 1110., Rochester, N. Y., a

corporation of Delaware Original application July 2, 1946, Serial No. 680,983. Divided and this application October 1, 1949, Serial No.-119,094

9 Claims.

This invention relates to chairs of the variety adapted for use by the medical profession during examinations, treatments and minor operations, one object of the invention being to provide an improved chair of such character having a more adjustable, convenient, and efficient construction.

Another object is to provide a chair of the above character having head, back, arm, and foot rests adjustable to and from positions 1ying substantially in the plane of the chair seat, for converting the chair into a substantially fiat,

' table-like support.

Another object is to provide such a chair having an adjustable seat frame which may be tilted throughout a range of positions relative to the top of the elevating column.

Another object is to provide an efficient and easily workable means of locking said seat frame in the desired tilted position. I

This application is a division of my copending application, Serial No. 680,983, now Patent No. 2,558,143, filed on July 2, 1946, Medical Prac tice Chair, to which reference may be had for parts disclosed but not claimed herein.

To these and other ends the invention resides in certain improvements and combinations of parts, allas will be hereinafter more fully de-- scribed, the novel features being pointed outin' the claims at the end of the specification.

In the drawings:

Fig. 1 is a side elevation of a chair embodying the'present invention and arranged to support a patient in an uprightsitting position;

Fig. 2 is a top plan view of the chair arranged horizontally with portions of the seat broken away to disclose parts of the mechanism;

Fig. 3 is an enlarged top plan view of the seat frame and associated mechanism partly in section and partly broken away;

Fig. 4 is an enlarged fragmentary view of certain details of the mechanism shown in Fig. 3;

Fig. 5 is a fragmentary side elevation of the seat frame, partly broken away to show a looking means;

Fig. 6 is a sectional view on line 20-20 in Fig. 5, and

Fig. 7 is a sectional view substantially along the line 'l'! in Fig. 4.

The preferred embodiment of the invention herein disclosed, by way of illustration, comprises a chair having a circular base Mi, Fig. 1, supporting an electric motor 4| and a housing 42 for hydraulic mechanism for raising and lowering a chair supporting column 43' which is mounted for rotation also in the housing, as well understood in the art. At 44 is ent invention.

The chair column carries at its top a generally v circular supporting head 4 6 formed with bearings 41, Figs. 2 and 3, for trunnions 48 by which a seat frame 49 is supported for tilting movement on the chair base. Means are provided, as hereafter described, for releasably locking the seat frame in adjustably tilted positions. The seat frame 49 is a generally rectangular, hollow frame, as shown, on which the back rest, arm rests and leg and foot rests, shown generally at 83, 85, 81 and 89, respectively (Fig. 1 are supported in connected relation for movement simultaneous- 1y to difierent adjusted positions.

The rear of the seat frame is formed with an integral, hollow, box-like portion indicated generally at 9| (Fig. 3), with which the back rest is pivotally connected. This portion BI comprises spaced, rearwardly extending walls 93 (Fig. 1), the front and lower sides of which are curved substantially in 'a semi-circle as shown in Figs. 1 and 5. a spindle 95 (Fig. 1) pivotally supporting an irregularly shaped member (not shown) forming the base portion of the back rest. Fixed on and extending upwardly from this irregularly shaped member is a post 91 (Fig. 1) slidably received in a bearing in a member 99 having in its rear face an undercut or dovetailed vertical groove (not shown) slidably receiving a similarly shaped tongueon a member llll. Member IIH is provided with a clamp (not shown) operated by a handle I83 for locking the tongue in a vertical position in the grooves in member 99. Member H is provided at its upper end with lugs I05 between which is pivotally supported a depending arm I87 secured to the rear side of a substantially rectangular, padded back rest [09 shaped to conform substantially to the patients back.

As pointed out in my above copending application, Serial No.' 680,983, when the back rest is tilted backwardly and lowered to a table-like position, back rest pad IE9 is moved towards the seat to maintain a normal distance therebetween. This is an important feature for, otherwise, the pad [09, during such movement, would slide up the patients back, uncomfortably disarranging his clothes, and leaving a gap between it and the seat.

Each arm rest comprises a frame Ill hav- Walls 93 are formed with bearings and r r ing at its lower forward end a trunnion 5! (Fi 3) journaled in the side of the seat frame 49, as hereafter described and as described in my said copending application. The upper rear end H3 (Fig. l) of arm rest frame iii is pivotally connected at l i5 with arms I ll extending forwardly from the part 9% of the back rest which slides on pivoted post 91.

Trunnions 5| are pivotally supported in a hearing in the side of the seat frame A9 comprising an outer boss H9 (Fig. 3) and an inner boss l2! (Fig. 4). Trunnions 51 extend inwardly beyond inner bosses l2! and are connected to one end of a pair of strong coiled springs I23 (Figs. 3 and 4) which are connected at the opposite ends thereof to the seat frame by bolts 125 (Fig. 3). Springs I23 serve to counteract the weight of the patient against the back rest and to assist in lifting the back rest and patient to a sitting position. Trunnions 5% are each also preferably connected to the leg and foot rest supporting mechanism by means of a lever l2! (Fig. 4) keyed thereto which in turn is connected to the leg rest frame mechanism by a pair of bars or links [29 (Figs. 3 and a). Links i29 are connected at the forward ends thereof to a lever [3| keyed to a shaft 533 (Fig. 3) mounted for rocking movement at its opposite ends in bearings (not shown) in the sides of the seat frame. Mounted to rock independently on shaft I33 is a sleeve I35 (Fig. 3) to the opposite ends of which are fixed a pair of spaced arms 13? (Fig. 3) having upper ends of gooseneck shape to avoid interference with the front end of the seat frame. Arms l3? form part of a hinged frame of rigid construction for supporting the leg and foot rests, as described and claimed in my copending application, Serial No. 119,095, Medical Practice Chair with Adjustable Leg and Foot Rest Supports, now Patent No. 2,612,940, granted October '7, 1952.

As explained above, the seat frame is supported for tilting movement on the top 46 of the elevating column 43 and the armrest structure is utilized in part for controlling means for locking the seat frame in adjustably tilted position on the column. Such means preferably comprises a sleeve 55 keyed on the inner end of the trunnion 5! of one of the arm rests (Fig. 4) inwardly of lever :21, as shown in Fig. 4. Fixed in this sleeve are one or more radially extending pins 52 received in inclined slots or notches 53 in a cap 55 rotatably and slidably mounted on the sleeve so as to be controlled for movement both concentrically and axially of the sleeve. The cap 5 5- has a strap 55 clamped thereto and forming part of the end of an angular lever 56, Figs. 3 and 4, extending rearwardly and upwardly along the under side of the adjacent arm rest. Lever 55 has a projecting portion or lug i39 (Fig. 4) which projects outwardly through a rectangular opening, as at M] (Fig. 4), formed in strap 55 for holding one end of said strap in position on said lever while allowing the opposite end thereof to be tightened by a screw i i-3 (Fig. l). Set concentrically in the cap is a threaded plug 52' of hardened steel having therein a socket 58 for the reception of a rounded and hardened bearing surface 59 at the left end of a thrust element or rod fill, as seen in Fig. 3. This end of the rod is thus supported concentrically with the trunnion of the arm rest, so as to be undisturbed by its tilting movement on the seat frame, and it will be seen that the swinging of lever 56 in either direction 4 rotates cap 54 whose inclined slots 53 move the cap axially of the sleeve to press its plug 51 against rod 65 to thrust it longitudinally. Rod 56 thrusts at its opposite end against the resistance of spring-actuated means for operating the locking means controlling the tilting movement of the seat frame on the elevated column of the chair base, as hereafter described. It will also be noted that lever 55 is mounted on cap as and is caused to follow the movements of the arm rests, so as to be conveniently and easily located for actuation by the operator of the chair. Sleeve 59 is keyed to trunnion 5| which in turn is keyed to the arm-rest frame I l I so that the arm rest cannot rotate relative to the seat frame without the corresponding rotation of trunnion 5i and sleeve 55). While cap 5A, to which lever fit is fixed, is rotated relative to sleeve 53 for releasing the seat-frame locking mechanism, cap 5:3 is caused to rotate with trunnions 5i as the arm rests rotate relative to the seat frame. That is, pins 52 on sleeve engage the slots in cap 53, and as the sleeve 5%] and trunnions 5! are rotated, cap 54 will either be rotated therewith, or cammed axially along sleeve 58. However, the camming action of cap St is opposed by the resistance of spring 63 and of the seat-frame locking mechanism, whereas the only resistance to the rotation of cap 54 with sleeve 58 results from the engagement between rounded bearing surface 5d, ofthrust rod 69, and socket 58 of plug 51. As the above resistance to rotation is considerably less than the above forces resisting the camming movement of cap 54, cap 5% is readily rotated with sleeve 59, trunnion 5i and arm rest frame Ill, as the arm rests are raised and lowered relative to the seat frame.

Thrust rod 5E has at the opposite end thereof a rounded and hardened bearing surface 61 which is seated in a socket {52 in a lever 63 pivoted at 6 5 on a lug tfion the head of the elevating col umn. The rod socket E2 is located concentrically with the axis of the seat frame trunnions t8, so that the rod is unaffected by tiliting-movements of the seat frame on the column. At is a coiled compression spring having one end seated in a recess in lever 63and the other end seated in a recess in anextended portion 67 of the adjacent column bearing 47. One function of this spring is to press lever 83 against rod 5!) and normally thrust it against plug 5? in cap 54.

1e means for releasably locking the seat frame in its adjustable tilted-positions on the base comprises, preferably, a block 38 (Figs. 3, 5, and 6) pivotally supported by trunnions 59 having hearings in lug 65 and a cooperating lug 'iil spaced therefrom on the head of the column. This pivoted block "53 is formed with a bearing opening which slidably receives a spindle 'H connected with the chair frame, as hereafter de scribed. Block 68 has a slot '52 extending inwardly to its spindle bearing to provide for compressive clamping of the block around the spindle to lock it thereto. Such locking compression of the block is preferably accomplished by means of a rod 73 sliding longitudinally in a bore in lug 65 with one end bearing against lever 53 and the other against the adjacent side of the block. The opposite side of the block is supported by a short stop rod M fixed in lug l6.

Locking spindle "H is carried by a head 15 formed on or otherwise secured to the top of the spindle and pivoted on a spindle is carried in lugs, llprojecting-inwardly from an abutment 18 on the seat frame. A coiled compression spring [9, carried by an adjustable screw 80, on

It will be evident from this construction that.

the pressure of spring 66 against lever 63 normally'thrusts rod 13 longitudinally to compress block 68 into locking engagement with the spindle carried by the seat frame so as to lock the latter in adjusted position. Lever 56 may be rotated through a slight angle, however, to cam cap 56 axially of sleeve 59, as previously explained, and thereby thrust rod 60, against lever 63 and thus release block 68 to relieve its looking action on the seat frame spindle H, thus freeing the seat frame for tilting movement as long as lever 56 is held in such position. During such tilting movement of the seat frame, the

thrust rod 60 is'turned bodily about its end 6| concentric with the tilting axis of the frame, so as not toaffect the operation of the frame locking means, notwithstanding the location of the other end of the thrust rodin eccentric relation to such pivotal axis The invention supplies an improved and advantageous arrangement for locking the seat frame in adjustably tilted position on the elevating column. Such movement of the seat frame relative to the elevating column is controlled by a locking lever uniformly positioned along the rear side of one of the arm rests so as to be easily located by the operator with minimum attention and effort.

It will thus be seen that the invention accomplishes its objects and while it has been herein disclosed by reference to the details of a preferred embodiment, it is to be understood that such disclosure is intended in an illustrative, rather than a limiting sense, as it is contemplated that various modifications in the-construction and arrangement of the parts will readily occur to those skilled in the art, within the spirit of the invention and the scope of the appended claims.

I claim:

1. A chair comprising a base, a frame mounted for tilting movement on said base and provided with a seat, a back rest pivotally and slidably mounted on said frame, arm rests pivotally connecting said frame and back rest for movement of the arm rests with said back rest, means for locking said frame in different tilted positions, and an operating lever for said locking means connected and movable with one of said arm rests during the pivotal movement of the arm rests relative to said frame.

2. A chair comprising a base, a seat frame mounted on said base for tilting movement about one axis, a back rest pivotally and slidably connected with said frame, arm rests connected with said back rest and pivotally connected with said frame for movement about an axis spaced from said first axis, locking means for securing said frame in adjustably tilted position on said base, actuating means for said locking means having a part concentric with each of said axes, and a lever for operating said actuating means connected and movable with one of said arm rests during the pivotal movement of the arm rests relative to said frame.

3. A chair comprising a base, a seat frame mounted on said base for tilting movement about one axis, a back rest pivotally and slidably connected with said frame, arm rests connected with said back rest and pivotally connected with said frame for movement about anaxis spaced from said first axis, means for locking said frame in adjustably tilted position on said base, and means for operating said locking means comprising a thrust element having opposite end portions located substantially on said axes, respectively.

4. A chair comprising a base, ,a seat frame mounted on said base for tilting movement about an axis, a back rest slidably connected With said frame for pivotal movement about an axis, arm rests movably connected with said back rest and connected with said frame for pivotal movement about an axis, means for locking said frame in adjustably tilted position on said base, actuating means for said locking means having a portion located substantially on the tilting axis of said seat frame, a thrust element having one end connected with said portion and the other end located substantially on the pivotal axis of one of said arm rests, and means comprising a lever connected and movable with said one of said arm rests during the pivotal movement of the arm rests relative to said frame, said lever being movable relative to said arm rest for moving said thrust element and operating said locking means in any adjusted position of said rests and seat frame.

5. A chair comprising a base, a seat frame mounted on said base for pivotal movement about an axis, a back rest pivotally and slidably connected with said frame, an arm rest connected with said back rest and connected with said frame for pivotal movement about an axis, means for locking said frame in adjustably tilted position on said base and having an operating portion located substantiallyon said frame axis, a thrust rod connected at one end with said portion and having its opposite end located substantially on said arm rest axis, cam means on said arm rest axis for moving said rod longitudinally of said axis, and a lever movable with said arm rest during the pivotal movement of the arm rest relative to said frame, said lever being movable relative to said arm rest for actuating said cam means and operating said frame looking means.

6. A chair comprising a base, a seat frame mounted on said base for tilting movement about an axis, a back rest pivotally and slidably connected with said frame, arm rests movably connected with said back rest and connected with said frame for pivotal movement about an axis, means for locking said frame in adjustably tilted position on said base, actuating means forsaid locking means having a lever movably mounted on said base, one end of said lever being located substantially on the tilting axis of the seat frame, and a thrust element having one end in engagement with said end of said lever, the other end of said thrust element being located substanitally on the pivotal axis of one of said arm rests.

7. A chair comprising a base, a seat frame mounted on said base fortilting movement about an axis, a back rest pivotally and slidably connected with said frame, arm rests movably connected with said back rest and connected with said frame for pivotal movement about an axis, means for locking said frame in adjustably tilted position on said base, actuating means for said locking means having a lever pivoted on said base, a spring for moving said lever in one direction for actuating said locking means, one end of said lever being located substantially on the tiltingi axis'vof the seat frame, and a thrust elementv having one end in engagement with said end-70f said lever for moving said lever in the opposite direction to release said locking means, the other ,end of said thrust element being 10- catedcsubstantialiy on the pivotal axis of one of said arm rests.

8. A chair comprising a base, a seat frame mounted on said base for pivotal movement'about an axis, a back rest pivotally and slidably connected with said frame, an arm rest pivotally connected with said back rest and connected with said frame for pivotal movement about an axis, clamping means for locking said frame in adjustably tilted position on said base, actuating means for said clamping means having a part located substantially on the tilting axis of said seat frame, and a thrust element having one end connected with said part and the other end located substantially on the pivotal axis of one of said arm rests.

9. A chair comprising a base, a seat frame mounted on said base for pivotal movement about an axis, a. back rest pivotally and slidablyconnected with said frame, an arm rest pivotally connected with said back-rest and connected with said frame for pivotal movement about an axis, an elongated element pivotally attached to and movable with said seat frame; a clamping means on said base for releasably engaging said element for locking said frame. in adjustably tilted posi tion on said base, actuating means for said clamping means having a part located substantially on the tilting axis of said seat frame, and a thrust element having one end inengagement with said part and the other end located substantially on the pivotal axis of one of said arm rests.

References Cited in the file of this patent UNITED STATES PATENTS ma jaw

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