Patents Assigned to Sifa Sitzfabrik GmbH
  • Patent number: 6467844
    Abstract: Clamping arrangement for seat carriers of chairs, in particular office swivel chairs, whereby the seat carrier is provided with at least two parts which can be pivoted in relation to each other about a common axis and to each of which a lamellar stack is hinged, whereby the lamellar stacks intermesh with each other, whereby both lamellar stacks are provided with recesses through which they are hinged to a common transverse pin, and the recesses of at least one of the lamellar stacks allow the lamellar stack to move across the axis of the common pin, and whereby means are provided which can be moved into and out of a clamped position with the lamellar blades of both stacks, whereby the clamping means are supported on one of the two parts or another additional part of the seat carrier, and a stop for the lamellar blades is provided in the seat carrier opposite to the clamping direction, whereby clamping means (9) are pivotably arranged in part (1), and its pivoting axis extends across the axis of the common pin
    Type: Grant
    Filed: March 14, 2001
    Date of Patent: October 22, 2002
    Assignee: Sifa Sitzfabrik GmbH
    Inventor: Reinhard Gebhard
  • Patent number: 6322144
    Abstract: The invention concerns a seat support for revolving chairs, in particular office revolving chairs, comprising a metal body in the shape of a pan, provided with top fixing elements for the seat lower part or seat plate, a bottom part for receiving the conical end of a support post adjustable in height, rear assembling elements for assembling said support to a seat back support and at least a lateral or front sleeve, provided for at least an actuating lever. The pan-shaped metal body has side walls opening obliquely frontwards at least partially into an angle ranging between 20 and 70 relative to the seat support longitudinal median axis, and are joined therein with a front wall. The pan-shaped metal body horizontal transverse section, formed by the side walls and the front wall tapers towards the tub base.
    Type: Grant
    Filed: March 24, 1999
    Date of Patent: November 27, 2001
    Assignee: Sifa Sitzfabrik GmbH
    Inventor: Reinhard Gebhard
  • Patent number: 6131996
    Abstract: A seat platform carrier for a chair tilts backward and forward relative to a base part when a load, such as a person sitting is the chair, is placed on the seat carrier. A resetting mechanism positioned the seat platform carrier to the same initial position when the load is removed. A lamellar pack attached to a hand lever provides the user with a means to lock the seat platform carrier in a desired tilted position. A height adjusting actuator is included in the base part to permit the user to select an appropriate seat platform height. A user sitting on the seat platform carrier is able to freely tilt forward or backwards.
    Type: Grant
    Filed: June 2, 1999
    Date of Patent: October 17, 2000
    Assignee: Sifa Sitzfabrik GmbH
    Inventor: Reinhard Gebhard
  • Patent number: 5884969
    Abstract: A release for a seat-back height adjuster, especially for office chairs, in which the height adjuster consists of a housing (1) in which a flat seat-back bearer (2) is held by a ball catch clamp (3, 4), where the seat-back bearer (2) has recesses or apertures (3) arranged one behind the other for locking balls (4) which are held in the recesses of apertures by means of spring-loaded clamping bevels (5'), and in which the clamping bevel (5') can be disengaged against the force of the spring by a caliper (8) guided laterally out of the housing (1), where there is a base plate (7) secured in the housing (1) which has a groove (16) fitted in the axis of the caliper (8) having a narrower cross section for the end of the caliper (8) at which the latter is inserted into the housing (1) and the base plate (7), and the groove (16) has a broader cross section in which a shuttle (5) provided with the clamping bevel (5') for the ball (4) and is wider than the narrower cross section of the groove (16), is slidingly guided
    Type: Grant
    Filed: December 19, 1997
    Date of Patent: March 23, 1999
    Assignee: SIFA Sitzfabrik GmbH
    Inventor: Reinhard Gebhard
  • Patent number: 5882078
    Abstract: A clamp (1) for adjustable-height seat-backs, consisting of a guide member (2) for a tubular component (3) of the seat-back and a clamping device for clamping said tubular component in the guide member, the clamping device consisting of a clamping member (10) fitted on an upper pivot to swivel on the tubular component (3) or a component beside and firmly secured to it, and an actuator (6), the actuator (6) being fitted beneath the pivot of the clamping member (10) so as to rotate behind it in relation to the tubular component (3), and the actuator (6) having at least two different diameters from its pivot.
    Type: Grant
    Filed: November 10, 1997
    Date of Patent: March 16, 1999
    Assignee: SIFA Sitzfabrik GmbH
    Inventor: Reinhard Gebhard
  • Patent number: 5882077
    Abstract: The invention concerns the height-adjustment of the back-rests of chairs, especially office chairs, consisting of a housing (1) in which a flat back-rest carrier (2) is held by a ball-stop clamp (3, 4), the back-rest carrier (2) being provided with a series of indentations or holes (3) arranged behind one another in an axial direction for the stop balls (4) which are held in the indentations or holes (3) by means of a spring-loaded clamping bevel (5'). The clamping bevel (5') can be brought out of contact by a push-button (8) guided sideways from outside the housing against the spring force, spring-loaded means (10, 11) being arranged in the housing (1) for the prevention of sideways play of the back-rest carrier (2).
    Type: Grant
    Filed: November 25, 1997
    Date of Patent: March 16, 1999
    Assignee: SIFA Sitzfabrik GmbH
    Inventor: Reinhard Gebhard
  • Patent number: 5638925
    Abstract: The present invention relates to a jerk arresting mechanism to prevent the back rests of office chairs from unexpected movement such as rebounding and impacting upon users in an undesirable fashion. More generally, the mechanism described positively arrests an acceleration of one part moving relative to another part. This is accomplished in a housing fastened to one of the parts, wherein the mechanism resides, through which a spirally contoured shaft is passed that is connected to the other part. As the acceleration exceeds a predictable threshold, a nut with an outer toothed surface is axially translated relative to the shaft movement and engages a complementarily toothed surface integral with the housing. This engagement stops the rotational and linear movement of both the nut and shaft thereby arresting the movement of the parts relative to each other.
    Type: Grant
    Filed: February 24, 1995
    Date of Patent: June 17, 1997
    Assignee: Sifa Sitzfabrik GmbH
    Inventors: Maria Neumueller, Angelika Gebhard
  • Patent number: 5588706
    Abstract: A control mechanism for a seat carrier of a chair, especially a swivel chair. A pivotable part is clamped and released by lamellae with rotatably anchored ends. One set of ends is anchored without play; the other, with play. The ends anchored with play are suspended via holes from a clamping bolt which can slide, inside the clamping mechanism, against a spring that clamps the pivotable part. The lamellae are released by a control lever. The clamping bolt is slideably fitted in a pressure sleeve of diameter greater than the holes in the lamellae. The bolt behind the pressure sleeve has a stop that bears against the pressure sleeve during active clamping. On its other side this bolt passes through the wall at which the clamping action takes place. The outside of the clamping bolt, at a distance from this wall, has a mounting for a pressure spring that acts between the bolt and the wall. The pressure spring pushes the bolt outward, thus directing the clamping force to the lamellae.
    Type: Grant
    Filed: October 14, 1994
    Date of Patent: December 31, 1996
    Assignee: Sifa Sitzfabrik GmbH
    Inventors: Maria Neumueller, Angelika Gebhard