US1699894A - Adjustable chair back - Google Patents

Description

Jan. .22, 1929.

E. o. KLEMM ADJUSTABLE CHAIR BACK 2 Sheets-Sheet 1 Filed Feb. 9, 1925 Jan. 22, 1929. 1,699,894

E. O. KLEMM ADJUSTABLE CHAIR BACK Filed Feb. 9, 1926 2 Sheets-Sheet 2 Patented Jan. 22, 1929.

ME STATES EDWIN O. KLEMM 0F SAGINAW, MICHIGAN.

ADJUSTABLE CHAIR BACK.

Application filed February The present invention relates to an adjustable back for chairs, and has for its object to provide a device of thischaracter which embodies novel features of construction, whereby the chair back can be readily adjusted to diflt'erent positions and locked at that particular inclination or position which may be desired for the comfort of the occupant of the chair.

Further objects of the invention are to provide a chair back adjusting device which can be readily applied to a chair without disfiguring the same, which enables the inclination of the chair iack to be adjusted by proper manipulation of the chair back without touching any of the parts of the supporting device, and which enables the inclination or position of the chair back to be quickly adjusted by the occupant of the chair, and at the same time prevents such a sudden drop of the chair back as would be accompanied by a heavy shock and perhaps breakage of the parts. I

Certain embodiments of the invention are shown and described in this application for illustrative purposes, although it will be understood that many modifications and changes can be made in the details of construction without departing from the spirit ofthe invention.

For a full understanding of the invention reference is to be had to the following clescription and accompanying drawings, in which, 7

Figure 1 a perspective view of atragmentary portion of a chair provided with a swinging back having a supporting and ad justing mechanism which is constructed in accordance with the invention, aportion of the chair back being broken away to disclose the mechanism at the back thereof.

Figure 2 is a rear view of the rack mechanism, showing the same as detached from the chair. 1

Figure 3 is a longitudinal sectional view through the same.

Figure 4; is an enlarged transverse sectional view on the line H ofFigure 3.

Figures 5 to 9 inclusive are fragmentary portions of a chair back which is provided with a rack mechanism constructed in ac cordance with the invention, showing the s1 ccessive positions which are assumed by the parts as the chair is manipulated to bring the cross rod into engagement with a lower 9, 1926. SerialNo. 87,054.

notch and support the chair back at a slightly greater inclination.

Figures 10 to 13, inclusive are fragmentary views of portions of the main rack and retriever rack showing in a rather diagrammatic manner the action of the rack bars when the cross rod is shifted from engage ment with one of the notches of the main rack into engagement with the next lower notch of the main rack.

Figure 14 is a side view of a portion of a chair back provided with a slightly modified construction of the rack mechanism, the normal position of the retriever rack being shown by full lines, while the positionthereof when swung rearwardly is indicated by dotted lines.

Figure 15 is a transverse sectional view on the line 15-45 of Figure 14:.

Corresponding and like parts are referred to in the following description andfindicated on all of the views of the drawings by like reference characters.

Referring to the drawings, the reference character A designates a chair back which, asshown by Figure 1, has a'pivotal connec tion B with the frame C of the chair, where+ by it can be tilted into difierent angular positions. A mainrrack bar 1 is rigidly se cured to the rear of the chair back by suit-" able fastening members, such as those inclicated at 2, and a selected notch of this rack bar 1s adapted to be engaged by a cross rod 3 to support the back in. an adjusted position.

The crossrod is connected at its ends to the swinging arms 41 which are pivotally connected to the frame G of the chair, so that the cross rod can have the necessary up and down swinging movement to bring it into engagement with any selected one of the notches of the main rack bar 1 tosupport the chair back in the desired position.

The notches of the main rack bar 1 are formed with upwardly facing shoulders or seats i and inclined sides 1 and a keeper 5 is associated with the rack in a spaced and parallel relation thereto so that it will engage the cross rod 3 and serve to guide the cross rod up or down after the cross rod has been disengaged from the notches of the main rack 1 and swung rearwardlytherefrom.

A retriever rack 6 is mounted back of the main rack 1, having a limited movement toward and away therefrom. As shown on the drawings, the ends of the retriever rack 6 are connected by swinging links 7 to corresponding ends of the main rack, and the retriever rack is thereby suspended in such a manner that it normally tends to swing by gravity into engagement with the main rack. In the construction shown by Figures 1 to 4 of the drawings, the retriever rack 6 is arranged back 01" the main rack 1 and is formed with a longitudinal groove 6 which provides a clearance space-to re ceive the keeper 5 when the retriever rack is in normal position against the main rack. A

The teeth of. the retriever rack are formed with the upwardly facing shoulders 6? and inclined sides 6, and are so arranged that the shoulders 6 thereof will be at an elevation above the corresponding shoulders 1 of the main rack bar when the retriever rack is swung against the main rack.

The successive movements of the parts incident to shifting the cross rod 3 from en gagement with one of the notches of the main rack 1 into en agement with the next lower notch thereo to support the chair back at a slightly greater inclination are illustrated in their proper sequence by Figures 5to 9 of the drawings. In Figure 5 thereof the cross rod 3 is shown as engaging the third notch fromthe bottom of the main rack 1. In order to change the adjustment of the chair back it is grasped by the hand and tilted forwardly a sufficient amount to permit the cross bar 3 to swing by gravity away from the rack bar 1 and against the keeper 5. The cross bar at the same time engages the inclined portion of one of the teeth of the retriever rack 6 and swings the retriever rack rearwardly, the parts then assuming the position shown by Figure 6. Should it be desired to swing the chair back upwardly toward a vertical position, the cross rod 3 will be directed upwardly by engagement with the keeper 5 as the chair back is moved upwardly and when the desired inclination has been reached the chair backcan be released, whereupon the cross rod will be brought into engagement with one of the teeth of the main rack to support the chair back. a a a In the event it is desired to lower the chair back, it is permitted to drop rearwardly after being first moved forwardly a suflicient amount to disengage the cross rod 3 from the main rack 1. Upon this subsequent rearward movement of the chair back the cross rod 1 slides downwardly along the keeper 5 until it is engaged by the shoulder 6 of the next lower notch of the retriever rack as shown by Figure 7. This arrests the sliding movement of the cross rod along the keeper and upon further movement of the chair backthe cross rod is moved toward the main rack by means of the retriever rack, as shown by Figure 8. The further downward movement of the chair back causes the cross rod to be moved from the notch of the retriever rack 6 into the notch of the main rack 1 which is just below the notch of the main rack with which the rod was previously in engagement. This movement of the chair back can be repeated to bring the cross rod into engagement with a still lower notch of the main rack if it is desired to support the chair back at a greater inclination. It will thus be obvious that the chair back can be elevated as far as is desired by a single upward movement, although it can only be lowered one notch at a time, this beng desrable as a factor of safety to prevent sudden and unintended drops whic might be caused by carelessness and result in injury or damage to the chair.

The successive steps in a downward adjustment of the chair back are also illustrated by Figures 10 to 13, inclusive of the drawings. In Figure 10 the cross rod 3 is in normal engagement with one of the teeth of the main rack bar 1 and the retriever rack 6 is in engagement with the main rack bar. Figure 11 shows the position of the parts when the chair back is raised sufficiently to disengage the cross rod 3 from the main rack and permit the cross rod to move rearwardly into engagement with the keeper 5 at the same time swinging the retriever rack 6 rearwardly. Figure 12 shows the position of the parts upon the initial rearward movement of the chair back, the cross rod 3 having been arrested in its downward movement along the keeper 5 by engagement with the next lower notch of the re triever rack 6. The final position of the parts is shown by Figure 13, showing tllt' cross rod 3 as aving been brought into engagement with the next lower notch of the main rack 1 by the subsequent downward movement of the chair back. The retriever rack 6 is supported by the links 7 so that it always has a parallel relation to the main rack as it swings downward and away from the same, and it normally swings by gravity against the main rack, although it is not sufliciently heavy to offer material assistance to the downward movement of the cross rod 3 when the latter is disengaged from the main rack.

A slight modification is shown by Figures 14 and 15, in which the keeper 5" is formed integral with the main rack 1", and the re triever rack is mounted. at one side of the keeper, being supported by the swinging arms 4, and engaging stop )lIlS 8 to limit the inward movement thereo The notches of the main rack 1 and the retriever rack 6 are formed and arranged in the same relation to each other as previously described and engage the crossrod 3 in the same man ner. Both forms of the invention provide a construction which will effectively support the chair back at any desired angle and permit the chair back to be adjusted to a different angle without difiiculty, such adjustment being possible by manipulation of the chair back without the necessity oi touching the rack mechanism or cross rod.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is: a a

1. In a device of the character described, the combination with a tiltably mounted back member, of means for adjustably supporting the back member, and means including a rack and a device having a plurality of seats and actuated longitudinally of the rack by movements of the back member to vary the adjustment of the supporting means.

2. In a device of the character described, the combination with a fixed part of a tilt ably mounted back member, means for adjustably supporting the back member including a toothed member, a cross bar carried by the fixed part, and movable means disposed opposite the toothed member to be actuated by temporary engagement with said cross bar, said movable means having means engaging said cross bar whereby the connecting device is limited in its travel to the distance between two successive teeth of the toothed member to prevent a downward adjustment of the supporting member for more than a single tooth at each operation.

3. In a device of the character described, the combination with a tiltably mounted back member, of means for adjustably supporting the back member, and means including a rack and an opposite carrier having a series of seats staggered in relation to the rack and actuated by successive back and forth movements of the back member to lower the same with a step by step action.

l. In a device of the character described, the combination with a tiltably mounted back member, and a transverse rod, of a rack mounted upon the back member and formed with a series of notches any selected one of which is adapted to engage the rod, and means separate from said rod and disposed to temporarily receive the red when actuated by movements of the back member and limited in its travel to shift the rod from one notch into engagement with the next successive notch of the rack.

5. In a device of the character described, the combination with a tiltably mounted back member and a transverse rod, of a main rack mounted upon the back member and formed with a series of notches any selected one of which is adapted to engage the rod, and a retriever member movable toward and away from the main rack and having a seat adapted to be temporarily engaged by the transverse rod and limited in its travel from a position opposite one notch to a position opposite the next succeeding notch of the main rack to efiect a step step downward adjustment.

6. In a device of the character described, the combination with a tiltably mounted back member and a transverse rod, of a main rack mounted upon the back member and formed with a series of notches any selected one of which is adapted to receive the rod, a retriever member extending longitudinally of said rack and having a plurality of seats, swinging links connecting the retriever member to the rack whereby the retriever member is movable toward and away from the rack and normally swings toward the same by gravity, said retriever member being adapted to temporarily receive the transverse rod and return it to a diilerent notch of the main rack upon a back and forth movement of the back member.

7. In a device of the character described, the combination with a tiltably mounted back member and a transverse rod, of a main rack mounted upon the back and formed with notches any selected one of which is adapted to engage the rod, a keeper extendmg along the rack in a spaced relation thereto for guiding the rod along the rack, and a retriever member movable in parallelism to the rack and having a plurality of seats adapted to en age the rod and return it to a diflerent note 1 of the main rack upon a back and forth movement of the back member.

8. In a device of the character described, the combination with a tiltably mounted back member and a transverse rod, of a main rack mounted upon the back member and formed with a plurality of notches any se lected one of which is adapted to engage the rod, a retriever member, and swinging links connecting the retriever member to the main rack whereby it is movable toward and away from the main rack, said retriever member being formed with notches which have a staggered relation to the notches of the main rack, whereby it will engage the i rod and return it to a different notch of the main rack upon a back and forth movement or the back member.

9. In a device of the character described, the combination with a tiltably mounted back member and a transverse rod, of a main rack mounted upon the back and formed with a plurality of notches any selected one of which is adapted to engage to receive the rod and return it to adifierent notch of the main rack upon a back and forth movement of the back member.

10. In a device of the character described, the combination with a tiltably mounted back member and a transverse rod, of a main rack mounted upon the back member and formed with a plurality of notches any selected one of which adapted to receive the rod, a keeper extending along the rack in a spaced relation thereto for guiding the rod along the rack, a retriever rack, swinging links connecting the ends of the retriever rack to the main rack whereby the retriever rack is movable toward and away from the main rack and always has a parallel relation thereto, the notches of the main rack and retriever rack havin g upwardly facing seats and inclined aides and the seats of the retriever rack being above the corresponding seats of the main rack, whereby upon a back and forth movement of the back member the retriever rack will receive the rod and return it to a di'l'lerent notch of the main rack.

In testimony whereof I aflix my signature.

EDWIN O. KLEMM.

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