US2624396A - Chair having an angularly adjustable back rest - Google Patents

Chair having an angularly adjustable back rest Download PDF

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Publication number
US2624396A
US2624396A US676747A US67674746A US2624396A US 2624396 A US2624396 A US 2624396A US 676747 A US676747 A US 676747A US 67674746 A US67674746 A US 67674746A US 2624396 A US2624396 A US 2624396A
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Prior art keywords
lever
frame
rest
locking
chair
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US676747A
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Spraragen Louis
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AUTOMATIC LOCKING DEVICES Inc
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AUTOMATIC LOCKING DEVICES Inc
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60NSEATS SPECIALLY ADAPTED FOR VEHICLES; VEHICLE PASSENGER ACCOMMODATION NOT OTHERWISE PROVIDED FOR
    • B60N2/00Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles
    • B60N2/02Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles the seat or part thereof being movable, e.g. adjustable
    • B60N2/22Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles the seat or part thereof being movable, e.g. adjustable the back-rest being adjustable
    • B60N2/2227Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles the seat or part thereof being movable, e.g. adjustable the back-rest being adjustable and provided with braking systems
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T74/00Machine element or mechanism
    • Y10T74/20Control lever and linkage systems
    • Y10T74/20576Elements
    • Y10T74/20636Detents
    • Y10T74/2066Friction

Definitions

  • This invention relates to chairs or seats such as are used in coaches, busses, and the like, and more particularly to seats having parts which are adjustable as to adapt them for both sitting and reclining use.
  • An object of the invention is to provide an improved coach seat of this type wherein the parts may be quickly and conveniently adjusted by an occupant to any desired position between their limits, and there automatically looked, all
  • the locking and releasing means are connected to the movable back of a chair, and the arrangement is such that when the occupant desires to adjust the back to a new position it is only necessary to grasp the release lever and move same to a releasing position, then move the back as desired, and let go the lever.
  • the wedging members of the lock are automatically moved to locking position again so that the back is held in its new adjusted position until next manually released, and the action is such that the more pressure the chair back is subjected to, the tighter the wedging and the more positive the locking.
  • a feature of the invention is that only comparatively light force is required on the releasing lever to effect release of the seat back, even when the latter is partly supporting an occupants weight. Also, the provision of spring means, connected with the back for urging same forward, functions further to reduce the force required on the lever.
  • Another feature of the invention is the provision of a hand lever which may be located remote from the locking and releasing means for the seat back, and therefore may be mounted at the side of the sitting'surface of the seat, where an occupant has convenient access to it,
  • the locking means may therefore be mounted at the pivot for the back, close to the sturdy supporting structures thereof so that the structures need not be extended.
  • Still another feature of the invention is the provision of a locking and releasing means as above outlined which is selective in its operation so that the seat back is released for either forward or rearward movement in response to either forward or rearward movement respectively of the releasing lever.
  • This provides a better control of the seat back, especially if, as employed by the invention, there are means for continuously yieldably urging the back toward its upright forward position, since the locking means when released in response to movement of the lever functions as a ratchet due to its permitting movement of the seat back in one direction while preventing the same in the other direction.
  • Figure 1 is a fragmentary side elevation of a chair embodying the invention.
  • Fig. 2 is a fragmentary sectional view through the pivot and the locking means for the chair of Fig. 1, with the parts in locked position.
  • Fig. 3 is a view similar to Fig. 2 but showing the parts released in response to operation of the hand lever.
  • Fig. 4 is a fragmentary side elevation of a chair showing a modified form of the invention.
  • Fig. 5' is a section taken on the line 5--5 of Fig. 4 with spring 35a omitted for clarity.
  • Fig. 6 is a fragmentary section taken on the line 6-6 of Fig. 5, showing the parts of the looking mechanism in locked position.
  • Fig. '7 is a view similar to Fig. 6, but with the parts unlocked.
  • Fig. 8 is a section taken on the line 8-8 of Fig. 1, on an enlarged scale.
  • the invention is applied to a coach chair or seat having a frame H3, legs ll, arm rests l2, and a seating portion l3.
  • a back 14 carried in a frame I5 is mounted adjacent its lower edge on the rear portions 16 of the arm rests l2 so that it can be swung forwardly and rearwardly for adjustment.
  • an improved locking and releasing means for the back [4 to enable an occupant to quickly and easily adjust the latter to any desired position between its limits for either sitting or reclining use.
  • the occupant first moves a conveniently located lever which releases the lock, then the back is adjusted, and when the lever is let go, the back is automatically locked in the new position, this all being accomplished with a minimum of effort.
  • the frame portion 15 of one of the arm rests i2 has a stud fastened thereto extending inward and carrying a sleeve is having a cylindrical periphery relieved at its upper portion H] to provide a pair of oppositely directed wedging surfaces.
  • the other arm rest I2 has a pivot (not shown) aligned with the stud l7 and connected with the back I4 in any of various well known manners to support same for pivotal movement.
  • the sleeve I8 and stud serve as an anchor member for the lock, and hence are rigidly fastened together, as by welding and also Welded to the arm frame It to be immovable thereon.
  • a bushing 2 Rotatably carried by the sleeve I8 is a bushing 2:: having an operating arm 2
  • a bracket 22 is mounted on the frame of the back at the lower corner thereof (Figs. 1 and 8), said bracket having an arm 23 fastened to the frame with suitable bolts, and a hub 24 having an inner bearing surface 25 engaging the stud so that the hub is rotatable thereon.
  • the back M is pivotally movable forward or rearward about its mounting, to adapt the chair for various reclining or sitting uses.
  • the locking of the back M in any of the various adjusted positions is accomplished by locking means associated with the bracket 22 and the anchor member comprising the stud l1 and sleeve i8, and one of the characteristics of said locking means is the provision of smooth, as opposed to stepped, locking surfaces making possible substantially an infinite number of adjusted locked positions.
  • the bushing 20 has a segmental section thereof cut away sufficiently to .clear the wedging surfaces
  • the wedging surfaces I9 are arranged to approach the surface 25' as they merge with the cylindrical periphery of the sleeve IS.
  • a pair of locking rollers 26 and 2'5, yieldably held apart by a coil spring 28, are located in the space provided by the cut-away portion-of the bushing 2c, the rollers being large enough to wedge between the surfaces l9 and surface 25 near their closest points, and prevent turning of the hub 24 in either direction.
  • roller 26 is wedged to prevent clockwise rotation of the hub, and the roller 27 to prevent counterclockwise rotation, and'the bushing '26 is cut away sufficiently so that the edge 29 thereof clears the roller 25 when the latter is wedged in place, and the edge 33 similarly clears the roller 2?.
  • the roller 21 will again wedge and lock the hub, and the latter, due to the absence of steps in the bearing surface or race 25, may be locked to hold the back M in any of an infinite number of positions. If the bushing is turned counterclockwise, the edge 29 moves the roller 25 out of wedging position and releases the hub 24 and back M for clockwise or forward adjustment, and the roller 21 then functions as the ratchet, under the pressure of the spring 28. Whenever the bushing 20 is in the locking position of Fig. 2, the spring 28 will hold both rollers 26 and 21 in wedging and locking position.
  • This invention further provides means enabling an occupant of the seat to conveniently and easily operate the arm 2
  • extends forward along the side of the seating surface I3 and terminates at a point approximately midway thereof, where it is operatively connected with a handoperable lever 3
  • comprises a transverse slot 34 in the lever having convex side walls engagin the end of the arm, which is rounded for this purpose.
  • a helical tension spring 35 connected at one end to the frame If! and at the other end to a depending extension 35 on the hub of the lever, said extension being apertured as shown for re ceiving the spring end.
  • the spring 38 will operate so that an occupant need only remove his pressure from the back, and the latter will automatically follow to any new forward position desired.
  • the spring 38 also serves to counteract the effect of a persons weight on the back [4.
  • rollers 26 and 21 which are preferably of hard steel or alloy, provide a positive lock for the back 14 of the seat, and the more pressure the back is subjected to, the tighter the wedging of the roller opposing said pressure, and therefore the stronger the locking action.
  • this can be done with comparatively light pressure, regardless of whether or not that particular roller is opposing a substantial pressure at the time.
  • Fig. 1 provides for all of the comparatively heavy supporting members and the locking members being located at or near the pivotal mounting for the back I4 where they are of compact construction. This results in a saving of weight and materials.
  • the releasing means for the lock is such that the hand operable lever 3
  • a modified form of the invention is shown in Figs. 4 through 7.
  • a seat comprising a frame Illa, legs Ila, arm rests l2a and seating portion [3a has a back l4a carried by a pair of supporting members 22a fastened thereto by suitable bolts and pivotally mounted by means of studs Ila on rear portions lfia of the arm rests. As thus mounted, the back l4a may be moved forward or rearward for adjustment about the pivots Ilia.
  • one of the supporting members 22a is provided with a depending arm 39 apertured at its extremity and pin-connected to one end of a link 40 by means of a bifurcated connector 4
  • the other end of the link 40 is pinconnected to a dependin arm 4! of a bell crank 42 which is mounted for turning about a stud 43 carried by a bracket 44 fastened with bolts to the frame Illa.
  • movement of the back I la will cause turning of the bell crank 42, and if the latter is locked to the frame Illa so that it cannot turn, the back I 4a will be locked against movement.
  • the bracket 44 is provided with a sleeve encircling the stud 43 and having an outer cylindrical bearing surface 45 on which the bell crank 42 is pivotally carried, said sleeve having a portion l8a with an outer cylindrical surface of reduced diameter and which is relieved at its top to provide oppositely directed wedging surfaces Wu.
  • the sleeve portion lBa thus serves as an anchor member for the locking means for the bell crank 42, and to this end the latter has an enlarged bore or race 25: spaced from said sleeve portion, there being provided looking or wedging rollers 26a and 2111 located between the surfaces
  • a lever am is pivotally mounted on the stud 43 to extend through a slot in the arm rest brace 33a, the lever having an annular flange Zila extending into the space between the sleeve [8a and the race 25a.
  • the flange 20a has a segmental portion cut away to provide edges 23a and 30a for respectively engaging the rollers 26a and 21a selectively to move one or the other out of wedging position according to whether the lever 31a is moved forward or backward.
  • the stud 43 is anchored to the bracket by a set screw 46, and a collar 4! is provided at the other end of the stud, fastened by a similar set screw and engaging the side of the lever.
  • a helical coil spring 3811 is anchored at one end to the frame Illa and connected at its other end to an arm 48 of the bell crank 42, the spring being under continual tension and serving to move and yieldably hold the back [4a in a foremost upright position when the latter is not under the restraint of the locking means.
  • a coil spring 3511 (Fig. 4) is provided, having one end connected to the frame “la and the other end connected to a depending apertured lug 49 extending from the hub of the lever. Both the spring 35a and the roller spring 28a function to return the lever 3la to its intermediate position.
  • An adjustable chair having a frame; a rest pivotally mounted thereon and movable relatively thereto; wedging means located at the pivot for the rest for automatically locking the rest on the frame against movement in any and all adjusted positions of the rest; and a pivoted member movable through an arc in opposite directions independently of the rest for releasing the wedging means and freeing the rest for independent movement in either direction.
  • the releasing means includes a projecting hand operable member movable in reverse directions from a projecting neutral position, said releasing means being operative to release the rest for adjustment in one direction or the other depending on whether said member is positioned at one or the other side of said neutral position.
  • the releasing means includes a projecting hand operable member movable in reverse directions by an operator from a neutral position and yieldably held in said neutral position; and yieldable means for holding said member in said neutral position, said releasing means being operative to release and free the rest for adjustment in one direction or the other selectively in response to movement of the operable member from said neutral position, said yieldable means returning said member to said neutral position when disengaged by the operator.
  • a chair having a frame; a rest pivotally mounted on the frame to be angularly adjustable; wedging means for automatically locking the rest against movement in any and all adjusted positions on the frame, said means being interposed between the frame and rest at the pivot point of the latter; and manually engageable means remote from the said pivot point for releasing said wedging means to permit selected adjustment of the rest to desired position.
  • An adjustable chair having a frame; a rest thereon movable relatively thereto; a pair of relatively movable members operatively connected one to the frame, and the other to the rest to move therewith, one of said members having a race and the other having a surface facing and spaced from the race but extending in a direction approaching same, the members being so shaped and mounted that relative movement between the rest and the frame maintains said spaced relationship between the members substantially constant in all positions thereof; a locking member disposed between said race and surface to engage the race and the surface of the movable members to wedge between and lock same against movement whereby the rest and frame are locked together; and means for selectively moving the locking member out of its wedging position to release the rest for adjustment in either direction.
  • An adjustable chair having a frame; a rest thereon movably mounted thereon; a cylindrical stud rigidly mounted on the frame, having a portion of its periphery relieved; a rotatable member carried on the stud, having an internal annular race facing and spaced from the periphery of the stud, said member being connected to turn in response to movement of the rest; a locking member adapted to engage the race and the relieved periphery of the stud to Wedge between same and lock the rotatable member to the stud whereby the rest is locked to the frame; and means for selectively moving the locking member out of its wedged position to release the rotatable member so that the rest may be adjusted in either direction.
  • the member having the surface facing and approaching the race has a second surface similar to the first but removed therefrom and approaching the race in an opposite relative direction, in which there is a second locking member adapted to engage the race and the second surface whereby each locking member prevents movement of the rest in a direction opposite to the other, and in which there are means for moving the second locking member out of wedging position so that the rest may be adjustably moved in either direction.
  • the member having the surface facing and approaching the race has a second surface similar to the first but removed therefrom and approaching the race in an opposite relative direction, in which there is a second locking member adapted to engage the race and the second surface whereby each locking member prevents movement of the rest in a direction opposite to the other, and in which the means for moving the locking member out of wedging position includes a hand operable member movable in one direction to release said locking movement, movable in a reverse direction and having means operable in response to said reverse movement for releasing the second locking member whereby the rest may be adjustably moved in either direction selectively according to the direction of releasing movement of the operable member.
  • a chair having a frame; a back pivotally mounted at its bottom edge on the frame to be angularly adjustable; a control member pivotally mounted on the frame and connected with the back to control movement thereof, said member having an internal annular race concentrically located with respect to said pivot; an anchor member fastened to the frame to extend inside the race, having a surface facing and spaced from the race but extending in a direction approaching same, the members being so shaped and mounted that relative movement between the back and frame maintains said spaced relationship substantially constant in all positions thereof; a locking member disposed between said race and anchor member to engage the surface of the anchor member and the race of the control member to wedge against and lock the latter to the frame whereby the back is held in an adjusted position; means for yieldably holding the locking member in its wedged position; and a hand operable releasing lever pivotally mounted on the anchor member, having a lug'extending between the latter and the race adapted to engage the locking member and move same out of wedged position to release the back for adjustment.
  • An adjustable chair having a frame having a seat; a back pivotally mounted at its bottom on the rear of the frame to be angularly adjust-'1 able; means connected with the pivotal mounting of the back for automatically locking same to the frame in an adjusted position; means for releasing the locking means, including an elongate lever extending from the said pivotal mounting forwardly alongside the seat to terminate at a point remote from the back and at the side of a sitter; and a bell crank pivotally mounted on the frame at the side of the seat, pivotally and slidably connected with the lever to operate the release lever, said crank having an arm with a handle within easy reach of the sitter.
  • the member having the surface facing and approaching the race has a second surface similar to the first but removed therefrom and approaching the race in an opposite relative direction, in which there is a second locking member adapted to engage the race and the second surface whereby each lockin member prevents movement of the rest in a direction opposite to the other, and in which the means for moving the locking member out of wedging position includes a hand operable member yieldably held in a non-releasing position and movable in one direction and having means responsive to said movement to release said locking member, movable in a reverse direction and having means operable in response to said reverse movementfor releasing the second locking member whereby the rest may be ad- 9 justably moved in either direction selectively according to the direction of releasing movement of the operable member.
  • An adjustable chair having a frame; a rest thereon movable relatively thereto; a control member pivotally mounted on the frame and connected with the rest to control movement thereof, said member having an internal annular race concentrically located with respect to said pivot; an anchor member fastened to the frame to extend inside the race having a pair of surfaces facing and spaced from the race but extending to approach same in opposite directions, the members being so shaped and mounted that relative movement between the rest and the frame maintains said spaced relationship between the members substantially constant in all positions thereof; rollers, each engaging one surface of the anchor member and the race of the control member to wedge against and lock the latter to the frame to prevent bi-directional turning thereof whereby the rest is held in an adjusted position; a spring engaging the rollers to yieldably hold same in wedged position; and a hand operable releasing lever pivotally mounted on the anchor member, having means extending between the latter and the race, for selectively engaging and moving one or the other of the rollers out of wedged position according to movement of the lever in one direction or the other, so that the rest
  • An adjustable chair having a frame having a seat; a back pivotally mounted at its bottom on the rear of the frame, to be angularly movable; a control member pivotally mounted on the frame at one side of the seat so as to be located alongside a sitter, said member being connected by a link with the chair back to control the movement thereof; means for automatically locking the control member to the frame against movement in either direction to maintain the back in adjusted position; and a hand operable lever mounted on the frame and connected to the control member and having means for selectively releasing the locking means to free the back for movement in a predetermined direction whereby movement of the lever to a releasing position in one direction will allow the chair back to be moved to a new position in a corresponding direction.
  • the chair has a seat, in which the rest comprises the back of the chair mounted to pivot at its bottom, and in which the means for moving the locking member out of its wedged position includes a pivotally mounted lever having a common axis with the chair back, and extending forwardly at the side of the seat to terminate alongside a sitter for convenient operation by the latter.

Description

Jan. 6,. 1953 L. SPRARAGEN 2,624,396
CHAIR HAVING AN ANGULARLY ADJUSTABLE BACK REST Filed June 14, 1946 3 Sheets-Sheet 1 INVENTOR.
L. SPRARAGEN CHAIR HAVING AN ANGULARLY ADJUSTABLE BACK REST Jan. 6, 1953 3 Sheets-Sheet 2 Filed June 14, 1946 ATTORNEYS INVENTOR 110111.; .Yprarayefl ,Qtdawd b w QR Jan. 6, 1953 1.. SPRARAGEN CHAIR HAVING AN ANGULARLY ADJUSTABLE BACK REST 5 Sheets-Sheet 3 Filed June 14, 1946 INVENTOR.
.Sfrmrayen Louis WWW ATTOZNEYJ' Patented Jan. 6, 1953 CHAIR HAVING AN ANGULARLY ADJUST- ABLE BACK REST Louis Spraragen, Bridgeport, Conn,
assignor to Automatic Locking Devices, Incorporated, Bridgeport, Conn., a corporation of Connecticut Application June 14, 1946, Serial No. 676,747
V 15 Claims.
This invention relates to chairs or seats such as are used in coaches, busses, and the like, and more particularly to seats having parts which are adjustable as to adapt them for both sitting and reclining use.
An object of the invention is to provide an improved coach seat of this type wherein the parts may be quickly and conveniently adjusted by an occupant to any desired position between their limits, and there automatically looked, all
with a minimum of time and effort being required.
This is accomplished by the provision of a novel locking and releasing means associated with the relatively movable parts of the seat having locking surfaces which are continuous, as opposed to steps, and having wedging members automatically movable into locking position, and easily movable for release by means of a lever or the like located conveniently to the occupant.
In the illustrated embodiments of the invention, the locking and releasing means are connected to the movable back of a chair, and the arrangement is such that when the occupant desires to adjust the back to a new position it is only necessary to grasp the release lever and move same to a releasing position, then move the back as desired, and let go the lever. As the lever is released, the wedging members of the lock are automatically moved to locking position again so that the back is held in its new adjusted position until next manually released, and the action is such that the more pressure the chair back is subjected to, the tighter the wedging and the more positive the locking.
A feature of the invention is that only comparatively light force is required on the releasing lever to effect release of the seat back, even when the latter is partly supporting an occupants weight. Also, the provision of spring means, connected with the back for urging same forward, functions further to reduce the force required on the lever.
Another feature of the invention is the provision of a hand lever which may be located remote from the locking and releasing means for the seat back, and therefore may be mounted at the side of the sitting'surface of the seat, where an occupant has convenient access to it,
' and the locking means may therefore be mounted at the pivot for the back, close to the sturdy supporting structures thereof so that the structures need not be extended.
' Still another feature of the invention is the provision of a locking and releasing means as above outlined which is selective in its operation so that the seat back is released for either forward or rearward movement in response to either forward or rearward movement respectively of the releasing lever. This provides a better control of the seat back, especially if, as employed by the invention, there are means for continuously yieldably urging the back toward its upright forward position, since the locking means when released in response to movement of the lever functions as a ratchet due to its permitting movement of the seat back in one direction while preventing the same in the other direction.
Other features and advantages will hereinafter appear.
In the accompanying drawings:
Figure 1 is a fragmentary side elevation of a chair embodying the invention.
Fig. 2 is a fragmentary sectional view through the pivot and the locking means for the chair of Fig. 1, with the parts in locked position.
Fig. 3 is a view similar to Fig. 2 but showing the parts released in response to operation of the hand lever.
Fig. 4 is a fragmentary side elevation of a chair showing a modified form of the invention.
Fig. 5' is a section taken on the line 5--5 of Fig. 4 with spring 35a omitted for clarity.
Fig. 6 is a fragmentary section taken on the line 6-6 of Fig. 5, showing the parts of the looking mechanism in locked position.
Fig. '7 is a view similar to Fig. 6, but with the parts unlocked.
Fig. 8 is a section taken on the line 8-8 of Fig. 1, on an enlarged scale.
As shown in Fig. 1, the invention is applied to a coach chair or seat having a frame H3, legs ll, arm rests l2, and a seating portion l3. A back 14 carried in a frame I5 is mounted adjacent its lower edge on the rear portions 16 of the arm rests l2 so that it can be swung forwardly and rearwardly for adjustment.
According to the present invention there is provided an improved locking and releasing means for the back [4 to enable an occupant to quickly and easily adjust the latter to any desired position between its limits for either sitting or reclining use. In carrying out this adjustment, the occupant first moves a conveniently located lever which releases the lock, then the back is adjusted, and when the lever is let go, the back is automatically locked in the new position, this all being accomplished with a minimum of effort.
Two embodiments of the invention are shown herein as exemplary thereof. In the form illustrated in Figs. 1, 2, 3 and 8, the locking means is incorporated as part of one of the pivotal mountings of the back, further simplifying the structure of the device.
As shown in Figs. 1 and 8, the frame portion 15 of one of the arm rests i2 has a stud fastened thereto extending inward and carrying a sleeve is having a cylindrical periphery relieved at its upper portion H] to provide a pair of oppositely directed wedging surfaces. The other arm rest I2 has a pivot (not shown) aligned with the stud l7 and connected with the back I4 in any of various well known manners to support same for pivotal movement.
The sleeve I8 and stud serve as an anchor member for the lock, and hence are rigidly fastened together, as by welding and also Welded to the arm frame It to be immovable thereon.
Rotatably carried by the sleeve I8 is a bushing 2:: having an operating arm 2| extending forward along the side of the seating surface l3, the bushing functioning as a release for the look. For the purpose of pivotally connecting the back id to the frame H3 at the look, a bracket 22 is mounted on the frame of the back at the lower corner thereof (Figs. 1 and 8), said bracket having an arm 23 fastened to the frame with suitable bolts, and a hub 24 having an inner bearing surface 25 engaging the stud so that the hub is rotatable thereon.
As thus supported, the back M is pivotally movable forward or rearward about its mounting, to adapt the chair for various reclining or sitting uses.
The locking of the back M in any of the various adjusted positions is accomplished by locking means associated with the bracket 22 and the anchor member comprising the stud l1 and sleeve i8, and one of the characteristics of said locking means is the provision of smooth, as opposed to stepped, locking surfaces making possible substantially an infinite number of adjusted locked positions.
For this purpose, as shown in Fig. 2', the bushing 20 has a segmental section thereof cut away sufficiently to .clear the wedging surfaces |9 of the sleeve is so that a space exists between said surfaces and the outer bearing surface or race 25 of the hub, Fig. 2. The wedging surfaces I9 are arranged to approach the surface 25' as they merge with the cylindrical periphery of the sleeve IS. A pair of locking rollers 26 and 2'5, yieldably held apart by a coil spring 28, are located in the space provided by the cut-away portion-of the bushing 2c, the rollers being large enough to wedge between the surfaces l9 and surface 25 near their closest points, and prevent turning of the hub 24 in either direction. The roller 26 is wedged to prevent clockwise rotation of the hub, and the roller 27 to prevent counterclockwise rotation, and'the bushing '26 is cut away sufficiently so that the edge 29 thereof clears the roller 25 when the latter is wedged in place, and the edge 33 similarly clears the roller 2?. I
In order to unlock the hub 24 and therefore unlock the back 4 for adjustment either forward or rearward, it is only necessary to turn the bushing 2c in either a clockwise or a counterclockwise direction from the position of Fig. 2, by means of the arm 2 I. When the bushing is turned in a clockwise direction the edge 30 thereof will move the roller 2! out of its wedging position, and release the hub 24 forcounterclockwise turning only. During this turning the roller 26 remains substantially in wedging position due to the pressure of the spring 28, and functions as a clutch which permits counterclockwise turning of the hub, but prevents clockwise turning. When the bushing 20 is returned to the position of Fig. 2, the roller 21 will again wedge and lock the hub, and the latter, due to the absence of steps in the bearing surface or race 25, may be locked to hold the back M in any of an infinite number of positions. If the bushing is turned counterclockwise, the edge 29 moves the roller 25 out of wedging position and releases the hub 24 and back M for clockwise or forward adjustment, and the roller 21 then functions as the ratchet, under the pressure of the spring 28. Whenever the bushing 20 is in the locking position of Fig. 2, the spring 28 will hold both rollers 26 and 21 in wedging and locking position.
This invention further provides means enabling an occupant of the seat to conveniently and easily operate the arm 2| for turning the bushing 23 to release the back M for adjustment.
Referring to Fig. 1, the arm 2| extends forward along the side of the seating surface I3 and terminates at a point approximately midway thereof, where it is operatively connected with a handoperable lever 3| pivotally carried by a bracket 32 mounted on a cross-bar 33 of the arm rest I 2, the lever extending through a slot in the cross-bar, and the connection to the lever being such that forward movement thereof will result in release of back M for forward adjustment, and vice versa. As shown, the connection between the arm 2| "and the lever 3| comprises a transverse slot 34 in the lever having convex side walls engagin the end of the arm, which is rounded for this purpose. When it is desired to adjust the back l4 forward, the lever 3| is pushed forward. This raises the arm 2|, and'turns the bushing 20 counterclockwise which unlocks the back for forward adjustment. To release the back for rearward movement, the lever 3| is moved rearward as seen in Fig. 3, which lowers the arm 2| and turns the bushing in a clockwise direction.
For the purpose'of returning the hand lever 3| and therefore the arm 2|, to intermediate locked position as shown in Fig. 1 and for yieldably holding said lever and arm in this position, there is provided a helical tension spring 35 connected at one end to the frame If! and at the other end to a depending extension 35 on the hub of the lever, said extension being apertured as shown for re ceiving the spring end. Thus, after the seat back has "been adjusted and the occupant lets go of -the lever 3| it will be returned by the spring 35 to the intermediate position, and the spring 28 "acting on the rollers 25 and 2'! will automatically cause these to wedge and lock the back in the new position. The springs 28 and 35 aid'each other in this respect, both acting to return the lever to intermediate position.
I have found it to be advantageous also to yieldably urge the seat back l4 toward its foremost limit, and accordingly the bracket 22 supporting said back is provi ed with a forward extending arm 3'! connected at its free end to the frame It by a helical tension spring; 38. This facilitates the adjustment of the back, since when the lever 3| is moved rearward, the roller 26 which is still in wedging position, continues to oppose the spring 38 but now may function as a ratchet. As a result, an occupant of the seat, after moving the lever rearward, may adjust the back l4 rearward by merely pressing against same to move it to the desired position, and should this .pressure be removed before the lever is let go of, the back will not shift but will stay in the position it was placed. Also, when the back I4 is being adjusted forward after the lever 31 has been moved forward, the spring 38 will operate so that an occupant need only remove his pressure from the back, and the latter will automatically follow to any new forward position desired. The spring 38 also serves to counteract the effect of a persons weight on the back [4.
The rollers 26 and 21, which are preferably of hard steel or alloy, provide a positive lock for the back 14 of the seat, and the more pressure the back is subjected to, the tighter the wedging of the roller opposing said pressure, and therefore the stronger the locking action. However, when it is desired to move one of the rollers to releasing position this can be done with comparatively light pressure, regardless of whether or not that particular roller is opposing a substantial pressure at the time. i
It will be noted that the construction shown in Fig. 1 provides for all of the comparatively heavy supporting members and the locking members being located at or near the pivotal mounting for the back I4 where they are of compact construction. This results in a saving of weight and materials. Also, the releasing means for the lock is such that the hand operable lever 3| for same may be remote, as shown in the figure, from the locking and mounting members, and located to be especially convenient to the seat occupant, and this lever and the connecting arm 21 need not be of particularly heavy construction.
A modified form of the invention is shown in Figs. 4 through 7. A seat comprising a frame Illa, legs Ila, arm rests l2a and seating portion [3a has a back l4a carried by a pair of supporting members 22a fastened thereto by suitable bolts and pivotally mounted by means of studs Ila on rear portions lfia of the arm rests. As thus mounted, the back l4a may be moved forward or rearward for adjustment about the pivots Ilia.
For the purpose of controlling the positioning of the back Ma, one of the supporting members 22a is provided with a depending arm 39 apertured at its extremity and pin-connected to one end of a link 40 by means of a bifurcated connector 4| threaded on the link and locked by a nut as shown. The other end of the link 40 is pinconnected to a dependin arm 4! of a bell crank 42 which is mounted for turning about a stud 43 carried by a bracket 44 fastened with bolts to the frame Illa. As provided by these connections, movement of the back I la will cause turning of the bell crank 42, and if the latter is locked to the frame Illa so that it cannot turn, the back I 4a will be locked against movement.
Accordingly, as shown in Figs. 5 and 6, the bracket 44 is provided with a sleeve encircling the stud 43 and having an outer cylindrical bearing surface 45 on which the bell crank 42 is pivotally carried, said sleeve having a portion l8a with an outer cylindrical surface of reduced diameter and which is relieved at its top to provide oppositely directed wedging surfaces Wu. The sleeve portion lBa thus serves as an anchor member for the locking means for the bell crank 42, and to this end the latter has an enlarged bore or race 25: spaced from said sleeve portion, there being provided looking or wedging rollers 26a and 2111 located between the surfaces |9a and the race 25a, and a helical compression spring 28a yieldingly holding the rollers in wedging position.
To provide manually engageable means for moving the rollers 26a and 21a selectively out of their wedging positions, a lever am is pivotally mounted on the stud 43 to extend through a slot in the arm rest brace 33a, the lever having an annular flange Zila extending into the space between the sleeve [8a and the race 25a. The flange 20a has a segmental portion cut away to provide edges 23a and 30a for respectively engaging the rollers 26a and 21a selectively to move one or the other out of wedging position according to whether the lever 31a is moved forward or backward.
For the purpose of preventing the bell crank 42 and lever 3 la from sliding off the sleeve of the bracket 44, the stud 43 is anchored to the bracket by a set screw 46, and a collar 4! is provided at the other end of the stud, fastened by a similar set screw and engaging the side of the lever.
A helical coil spring 3811 is anchored at one end to the frame Illa and connected at its other end to an arm 48 of the bell crank 42, the spring being under continual tension and serving to move and yieldably hold the back [4a in a foremost upright position when the latter is not under the restraint of the locking means.
For the purpose of moving the lever 3m to its intermediate locking position when it is let go after adjustment of the back Ma, and to yieldably hold the lever in said position, a coil spring 3511 (Fig. 4) is provided, having one end connected to the frame "la and the other end connected to a depending apertured lug 49 extending from the hub of the lever. Both the spring 35a and the roller spring 28a function to return the lever 3la to its intermediate position.
The functioning of the lock and release in the modified form of the invention shown in Figs. 4 through '7 is substantially similar to that of Figs. 1, 2 and 3, except that the hand operable lever 31a. of the modified form is moved in a direction opposite to that in which the seat back Mat is to be adjusted.
Variations and modifications may be made within the scope of this invention and portions of the improvements may be used without others.
I claim:
1. An adjustable chair having a frame; a rest pivotally mounted thereon and movable relatively thereto; wedging means located at the pivot for the rest for automatically locking the rest on the frame against movement in any and all adjusted positions of the rest; and a pivoted member movable through an arc in opposite directions independently of the rest for releasing the wedging means and freeing the rest for independent movement in either direction.
2. The invention as defined in claim 1 in which the releasing means includes a projecting hand operable member movable in reverse directions from a projecting neutral position, said releasing means being operative to release the rest for adjustment in one direction or the other depending on whether said member is positioned at one or the other side of said neutral position.
3. The invention as defined in claim 1, in which the rest is movable forwardly and rearwardly relatively to the frame, and in which the releasing means includes a projecting hand operable member movable forwardly and rearwardly from a neutral position, said releasing means operating to release the rest for adjustment either forwardly or rearwardly in response to movement of the operable member forwardly or rearwardly respectively from said neutral position.
4. The invention as defined in claim 1 in which the releasing means includes a projecting hand operable member movable in reverse directions by an operator from a neutral position and yieldably held in said neutral position; and yieldable means for holding said member in said neutral position, said releasing means being operative to release and free the rest for adjustment in one direction or the other selectively in response to movement of the operable member from said neutral position, said yieldable means returning said member to said neutral position when disengaged by the operator.
5. A chair having a frame; a rest pivotally mounted on the frame to be angularly adjustable; wedging means for automatically locking the rest against movement in any and all adjusted positions on the frame, said means being interposed between the frame and rest at the pivot point of the latter; and manually engageable means remote from the said pivot point for releasing said wedging means to permit selected adjustment of the rest to desired position.
6. An adjustable chair having a frame; a rest thereon movable relatively thereto; a pair of relatively movable members operatively connected one to the frame, and the other to the rest to move therewith, one of said members having a race and the other having a surface facing and spaced from the race but extending in a direction approaching same, the members being so shaped and mounted that relative movement between the rest and the frame maintains said spaced relationship between the members substantially constant in all positions thereof; a locking member disposed between said race and surface to engage the race and the surface of the movable members to wedge between and lock same against movement whereby the rest and frame are locked together; and means for selectively moving the locking member out of its wedging position to release the rest for adjustment in either direction.
7. An adjustable chair having a frame; a rest thereon movably mounted thereon; a cylindrical stud rigidly mounted on the frame, having a portion of its periphery relieved; a rotatable member carried on the stud, having an internal annular race facing and spaced from the periphery of the stud, said member being connected to turn in response to movement of the rest; a locking member adapted to engage the race and the relieved periphery of the stud to Wedge between same and lock the rotatable member to the stud whereby the rest is locked to the frame; and means for selectively moving the locking member out of its wedged position to release the rotatable member so that the rest may be adjusted in either direction.
8. The invention as defined in claim 6 in which the member having the surface facing and approaching the race has a second surface similar to the first but removed therefrom and approaching the race in an opposite relative direction, in which there is a second locking member adapted to engage the race and the second surface whereby each locking member prevents movement of the rest in a direction opposite to the other, and in which there are means for moving the second locking member out of wedging position so that the rest may be adjustably moved in either direction.
9. The invention as defined in claim 6 in which the member having the surface facing and approaching the race has a second surface similar to the first but removed therefrom and approaching the race in an opposite relative direction, in which there is a second locking member adapted to engage the race and the second surface whereby each locking member prevents movement of the rest in a direction opposite to the other, and in which the means for moving the locking member out of wedging position includes a hand operable member movable in one direction to release said locking movement, movable in a reverse direction and having means operable in response to said reverse movement for releasing the second locking member whereby the rest may be adjustably moved in either direction selectively according to the direction of releasing movement of the operable member.
10. A chair having a frame; a back pivotally mounted at its bottom edge on the frame to be angularly adjustable; a control member pivotally mounted on the frame and connected with the back to control movement thereof, said member having an internal annular race concentrically located with respect to said pivot; an anchor member fastened to the frame to extend inside the race, having a surface facing and spaced from the race but extending in a direction approaching same, the members being so shaped and mounted that relative movement between the back and frame maintains said spaced relationship substantially constant in all positions thereof; a locking member disposed between said race and anchor member to engage the surface of the anchor member and the race of the control member to wedge against and lock the latter to the frame whereby the back is held in an adjusted position; means for yieldably holding the locking member in its wedged position; and a hand operable releasing lever pivotally mounted on the anchor member, having a lug'extending between the latter and the race adapted to engage the locking member and move same out of wedged position to release the back for adjustment.
11. An adjustable chair having a frame having a seat; a back pivotally mounted at its bottom on the rear of the frame to be angularly adjust-'1 able; means connected with the pivotal mounting of the back for automatically locking same to the frame in an adjusted position; means for releasing the locking means, including an elongate lever extending from the said pivotal mounting forwardly alongside the seat to terminate at a point remote from the back and at the side of a sitter; and a bell crank pivotally mounted on the frame at the side of the seat, pivotally and slidably connected with the lever to operate the release lever, said crank having an arm with a handle within easy reach of the sitter.
12. The invention as defined in claim '6 in which the member having the surface facing and approaching the race has a second surface similar to the first but removed therefrom and approaching the race in an opposite relative direction, in which there is a second locking member adapted to engage the race and the second surface whereby each lockin member prevents movement of the rest in a direction opposite to the other, and in which the means for moving the locking member out of wedging position includes a hand operable member yieldably held in a non-releasing position and movable in one direction and having means responsive to said movement to release said locking member, movable in a reverse direction and having means operable in response to said reverse movementfor releasing the second locking member whereby the rest may be ad- 9 justably moved in either direction selectively according to the direction of releasing movement of the operable member.
13. An adjustable chair having a frame; a rest thereon movable relatively thereto; a control member pivotally mounted on the frame and connected with the rest to control movement thereof, said member having an internal annular race concentrically located with respect to said pivot; an anchor member fastened to the frame to extend inside the race having a pair of surfaces facing and spaced from the race but extending to approach same in opposite directions, the members being so shaped and mounted that relative movement between the rest and the frame maintains said spaced relationship between the members substantially constant in all positions thereof; rollers, each engaging one surface of the anchor member and the race of the control member to wedge against and lock the latter to the frame to prevent bi-directional turning thereof whereby the rest is held in an adjusted position; a spring engaging the rollers to yieldably hold same in wedged position; and a hand operable releasing lever pivotally mounted on the anchor member, having means extending between the latter and the race, for selectively engaging and moving one or the other of the rollers out of wedged position according to movement of the lever in one direction or the other, so that the rest is released for adjustment selectively in one direction or the other.
14. An adjustable chair having a frame having a seat; a back pivotally mounted at its bottom on the rear of the frame, to be angularly movable; a control member pivotally mounted on the frame at one side of the seat so as to be located alongside a sitter, said member being connected by a link with the chair back to control the movement thereof; means for automatically locking the control member to the frame against movement in either direction to maintain the back in adjusted position; and a hand operable lever mounted on the frame and connected to the control member and having means for selectively releasing the locking means to free the back for movement in a predetermined direction whereby movement of the lever to a releasing position in one direction will allow the chair back to be moved to a new position in a corresponding direction.
15. The invention as defined in claim 7 in which the chair has a seat, in which the rest comprises the back of the chair mounted to pivot at its bottom, and in which the means for moving the locking member out of its wedged position includes a pivotally mounted lever having a common axis with the chair back, and extending forwardly at the side of the seat to terminate alongside a sitter for convenient operation by the latter.
LOUIS SPRARAGEN.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 830,146 Hamilton et al. Sept. 4, 1906 1,320,014 Lenard Oct. 28, 1919 1,628,764 Beech May 17, 1927 2,001,507 Stribling May 14, 1935 2,311,105 Will Feb. 16, 1943 2,414,341 Spraragen Jan. 14, 1947 FOREIGN PATENTS Number Country Date 358,192 France Dec. 9, 1905 369,645 France Nov. 20, 1906 848,742 France July 31, 1939 694,400 France Sept. 15, 1930 215,604 Great Britain May 15, 1924 352,186 Italy Sept. 8, 1937
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Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2778409A (en) * 1955-04-28 1957-01-22 Manton Ahlberg H Control for posture chairs
DE1116080B (en) * 1958-04-30 1961-10-26 Willy Staude Lockable swivel joint for reclining backrests on seats, especially for motor vehicles
DE1158390B (en) * 1956-12-12 1963-11-28 Daimler Benz Ag Adjustable backrest for vehicle seats
US3216766A (en) * 1962-05-14 1965-11-09 Rockwell Standard Co Infinite positional adjustment and one-way lock mechanism
US4070058A (en) * 1976-10-15 1978-01-24 Muehling Anthony A Infinite position seat back recliner
US4687251A (en) * 1984-06-22 1987-08-18 Aisin Seiki Kabushiki Kaisha Seat cushion for vehicles
FR2729346A1 (en) * 1995-01-13 1996-07-19 Hammerstein Gmbh C Rob OSCILLATING JOINT FERRULE FOR AN ADJUSTABLE VEHICLE SEAT
US6068097A (en) * 1997-12-24 2000-05-30 Ntn Corporation Dual-mode two-way clutch
US20110094356A1 (en) * 2009-04-16 2011-04-28 Robert Dunn Howerton Quick-Change Threading Tool Holder

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FR358192A (en) * 1905-09-30 1906-01-31 Dimitri Peress Improvements in control or adjustment devices or levers for cycles, motorcycles, motor cars, etc.
US830146A (en) * 1905-10-02 1906-09-04 Belton Tattnall Hamilton Locking device.
FR369645A (en) * 1906-01-11 1907-01-16 Belton Tattnall Hamilton Improvements in locking devices
US1320014A (en) * 1919-10-28 Reclining-chair
GB215604A (en) * 1923-06-06 1924-05-15 Foulke Engel Brandt Improvements in adjustable chairs
US1628764A (en) * 1924-05-14 1927-05-17 Kroehler Mfg Co Adjustable armchair
FR694400A (en) * 1930-04-24 1930-12-03 Armchair
US2001507A (en) * 1934-08-16 1935-05-14 George Hunt Latch mechanism
FR848742A (en) * 1938-01-12 1939-11-06 Audi Ag Seat with adjustable backrest
US2311105A (en) * 1940-12-19 1943-02-16 Tropic Aire Inc Chair or seat structure, and control for seat back-adjusting mechanism thereof
US2414341A (en) * 1944-07-20 1947-01-14 Automatic Locking Devices Inc Lever operated control device

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Publication number Priority date Publication date Assignee Title
US1320014A (en) * 1919-10-28 Reclining-chair
FR358192A (en) * 1905-09-30 1906-01-31 Dimitri Peress Improvements in control or adjustment devices or levers for cycles, motorcycles, motor cars, etc.
US830146A (en) * 1905-10-02 1906-09-04 Belton Tattnall Hamilton Locking device.
FR369645A (en) * 1906-01-11 1907-01-16 Belton Tattnall Hamilton Improvements in locking devices
GB215604A (en) * 1923-06-06 1924-05-15 Foulke Engel Brandt Improvements in adjustable chairs
US1628764A (en) * 1924-05-14 1927-05-17 Kroehler Mfg Co Adjustable armchair
FR694400A (en) * 1930-04-24 1930-12-03 Armchair
US2001507A (en) * 1934-08-16 1935-05-14 George Hunt Latch mechanism
FR848742A (en) * 1938-01-12 1939-11-06 Audi Ag Seat with adjustable backrest
US2311105A (en) * 1940-12-19 1943-02-16 Tropic Aire Inc Chair or seat structure, and control for seat back-adjusting mechanism thereof
US2414341A (en) * 1944-07-20 1947-01-14 Automatic Locking Devices Inc Lever operated control device

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2778409A (en) * 1955-04-28 1957-01-22 Manton Ahlberg H Control for posture chairs
DE1158390B (en) * 1956-12-12 1963-11-28 Daimler Benz Ag Adjustable backrest for vehicle seats
DE1116080B (en) * 1958-04-30 1961-10-26 Willy Staude Lockable swivel joint for reclining backrests on seats, especially for motor vehicles
US3216766A (en) * 1962-05-14 1965-11-09 Rockwell Standard Co Infinite positional adjustment and one-way lock mechanism
US4070058A (en) * 1976-10-15 1978-01-24 Muehling Anthony A Infinite position seat back recliner
US4687251A (en) * 1984-06-22 1987-08-18 Aisin Seiki Kabushiki Kaisha Seat cushion for vehicles
FR2729346A1 (en) * 1995-01-13 1996-07-19 Hammerstein Gmbh C Rob OSCILLATING JOINT FERRULE FOR AN ADJUSTABLE VEHICLE SEAT
US6068097A (en) * 1997-12-24 2000-05-30 Ntn Corporation Dual-mode two-way clutch
US6206164B1 (en) 1997-12-24 2001-03-27 Ntn Corporation Dual-mode two-way clutch
US20110094356A1 (en) * 2009-04-16 2011-04-28 Robert Dunn Howerton Quick-Change Threading Tool Holder

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