Including Pawl And Ratchet, Mating Serrations, Rack And Pinion, Or Gear Patents (Class 248/292.12)
  • Patent number: 7240715
    Abstract: An indexed limit stop for mounting on the headrail of a covering for architectural openings is easily connected to the headrail in overlying relationship with shade material wrapped on a roller in the headrail and has two elements that are pivotally interconnected and movable between selected fixed positions. The second element includes an abutment stop for engagement with the bottom rail of the shade material when the covering is fully retracted and can be positioned such that the abutment stop is spaced from the outer wrap of shade material to avoid damage to the shade material while being desirably positioned for intercepting movement of the bottom rail to limit retracting movement of the roller.
    Type: Grant
    Filed: December 22, 2004
    Date of Patent: July 10, 2007
    Assignee: Hunter Douglas Inc.
    Inventor: Brian M. Hoffmann
  • Patent number: 7209176
    Abstract: A remote camera head has a tilt frame attachable to a pan frame at multiple positions. A roll frame is attachable to the tilt frame at multiple positions. The camera head can be expanded or reduced in size as needed based on the space requirements of the camera and camera accessories mounted on the camera head. Waterproof or sealed slip ring assemblies and connectors allow the camera head to operate in wet environments, or even when submerged in water. The camera head can be quickly installed, set up, balanced, or reconfigured.
    Type: Grant
    Filed: February 19, 2004
    Date of Patent: April 24, 2007
    Assignee: Chapman/Leonard Studio Equipment
    Inventor: Leonard T. Chapman
  • Patent number: 7159831
    Abstract: An adjusting device (3) is suitable especially for use on a stand (1) for a surgical microscope (2). The adjusting device (3) makes it possible to move the surgical microscope (2) in a plane (9) perpendicular to the optical axis (8) of the surgical microscope (2). For this purpose, a transmission is provided in the adjusting device (3) which includes a coupling plate which is operatively connected to two force-transmitting elements. When this transmission is moved, at least one of the force-transmitting elements rolls off on the coupling plate. Alternatively, this transmission can be built up as a four-point linkage chain or contain a rhombic mechanism or lever mechanism. It is also possible to configure the transmission with belt elements or to configure the same as an eccentric arrangement having two offset rotation centers.
    Type: Grant
    Filed: February 23, 2004
    Date of Patent: January 9, 2007
    Assignee: Carl-Zeiss-Stiftung
    Inventors: Hartmut Gärtner, Gerhard Gaida, Franz Krug, Daniel Kolster, Alexander Enns
  • Patent number: 7147191
    Abstract: A display tilting apparatus includes a moving bracket that supports a display, a ratchet mechanism that controls pivoting of the moving bracket to a first direction, an anti-tilting mechanism that inhibits pivoting of the moving bracket to a second direction that is opposite of the first direction, and a fixed bracket that is pivotably connected to the moving bracket via a pivot axis. The anti-tilting mechanism includes a first anti-tilting member, and a second anti-tilting member that is mounted on the fixed bracket. The first anti-tilting member and the second anti-tilting member are mounted so as to make a physical contact to each other.
    Type: Grant
    Filed: July 16, 2004
    Date of Patent: December 12, 2006
    Assignees: Fujitsu Limited, Fujitsu Frontech Limited
    Inventors: Toshiyuki Ichikawa, Kenichi Miyazawa, Noboru Ishii, Takuma Yoshida, Satoshi Nishioka
  • Patent number: 7093313
    Abstract: A linkage mechanism for an adjustable arm assembly. The linkage assembly may be used to support an object, such as a headrest for use in connection with an examination table. The linkage mechanism provides structure to interlock or disengage two adjoining arm sections. The linkage mechanism controls relative movement of two adjoining arm sections without affecting the movement of non-adjoined sections or the headrest. The linkage mechanism further provides friction retention means so that the adjoining arms will retain their relative position to one another even if they are not in an interlocked position.
    Type: Grant
    Filed: September 29, 2003
    Date of Patent: August 22, 2006
    Assignee: The Brewer Company, LLC
    Inventors: Jack A. DeBraal, Michael J. Marchant
  • Patent number: 7063297
    Abstract: A mounting assembly includes first and second mounts that connect two objects, such as an electronic instrument housing and a surface. The first mount engages the second mount at a receptacle by way of cooperating detent members. One mount includes a resilient member, upon which cooperating detent members are disposed. The resilient member provides a bias to cause secure engagement of the cooperating detent members. Other features of the mounting assembly include rotational engagement between first and second cooperating detent members such that the angle of the first mount may be adjusted with respect to the angle of the second mount. Also, lead-ins may be included on the second mount so that the resilient members on the first mount may be depressed to ensure proper engagement of the cooperating detent members.
    Type: Grant
    Filed: June 30, 2003
    Date of Patent: June 20, 2006
    Assignee: Lowrance Electronics, Inc.
    Inventor: Kenton Jopling
  • Patent number: 7040589
    Abstract: An adjustable garment rod includes a mounting bracket, an inner housing, a resilient element and a suspension arm. The mounting bracket has an arm slot and a first toothed ratchet surface and second toothed ratchet surface formed alongside the arm slot. The inner housing is mounted pivotally in the arm slot and holds the suspension arm. The suspension arm extends out of the arm slot and has two toothed protrusions. The resilient element presses the suspension arm so that the toothed protrusions engage the toothed ratchet surfaces to hold firmly the suspension arm at a given angular position. Further, the garment rod uses several simple parts so that assembling the garment rod is easy and quick, which saves costs and time.
    Type: Grant
    Filed: March 1, 2004
    Date of Patent: May 9, 2006
    Assignee: Chi Yu Steel Co., Ltd.
    Inventor: Chi-Chung Wang
  • Patent number: 7025313
    Abstract: A side wing support adaptor. The adaptor has an extension wing having an engagement end and an attachment end provided at opposite sides thereof, so as to provide additional space to be hung at a lateral side of the tripod. The attachment end of the extension wing is provided with a fastener for attaching to a four-way locking mechanism that may be mated with add-ons or attachments. The engagement end of the extension wing is provided with an engagement member accommodating an accessory of the tripod. In an embodiment, the engagement member includes the same number of holes as that on a base plate mounted on the tripod platform. In an alternative embodiment, the engagement member includes a substantially circular piece formed with a central opening, and having a first face and a second face opposite the first face each formed with a plurality of meshable teeth.
    Type: Grant
    Filed: April 3, 2003
    Date of Patent: April 11, 2006
    Assignee: Videopart, Inc.
    Inventor: Chan-Min Ma
  • Patent number: 7021593
    Abstract: A vacuum suction apparatus with adjustment lever is disclosed. The structure of the vacuum suction apparatus includes a suction cup and a wheel base, which has a receptacle being attached by the suction cup from underneath, a semi-circular cogwheel being fixed on top of the receptacle, and an adjustment lever pivotally connected through an opening. The adjustment lever has a pinion on the bottom end, where the gearing of the pinion is to fit against corresponding gearing on the vertically erected rack at the center when the lever is in locked position. The upper portion of the lever also has a suction lock/release that allows the user to manually adjust the angle of the lever by pegging onto scooped cogwheel with a slider, so the suction strength can be adjusted desirably for continuously holding onto the same spot in extended use.
    Type: Grant
    Filed: October 26, 2004
    Date of Patent: April 4, 2006
    Inventor: Eagle Fan
  • Patent number: 6899308
    Abstract: Mechanisms for passive gravity compensation for a system of linkage arms are provided. Gravity compensation is provided through a pair of non-circular gear profiles, with an end of each linkage arm connected to a separate gear set of two non-circular cam bodies, by way of separate cables. Springs in the gear sets provide tension in the cables. The tension in each cable varies according to the angle through which the cam bodies have turned as a result of the co-operating non-circular surfaces of the cam bodies. This, in turn is based on the amount the arms have turned and thereby allows the tension in the cables to compensate for the moments on the arms due to gravity, whatever angles they are at, independently of the angle of the other arm. To achieve this for the first arm of the linkage, the tension in the cable leading to the second arm of the linkage is also transmitted as a torque to the first arm through a pulley mounted on the rotation axis of the first arm.
    Type: Grant
    Filed: July 31, 2003
    Date of Patent: May 31, 2005
    Assignee: Agency for Science, Technology and Research
    Inventors: Siew Loong Chow, Cheng Fu Shi
  • Publication number: 20040238714
    Abstract: A clamp assembly is disclosed including a clamp support half having an attachment end, the attachment end engaging a supporting structure, a lower clamp half releasably secured to the clamp support half, and wherein the lower clamp half accommodates an anti-rotation pin to prevent rotation about a longitudinal axis of the clamp assembly.
    Type: Application
    Filed: May 24, 2004
    Publication date: December 2, 2004
    Inventors: Stephen O. Slatter, William E. Kushner, Michael Burnley
  • Patent number: 6786461
    Abstract: A computer armrest includes an elbow supporter, a mouse pad and a connect arm. The elbow supporter and the mouse pad are movably connected with the connect arm so as to freely turn with the position of the elbow or the palm. The elbow supporter can be adjusted more than 90 degrees by means of the connect arm and also bent downward to be collapsed under a computer table not to lake any space on the table in case of not using.
    Type: Grant
    Filed: July 30, 2003
    Date of Patent: September 7, 2004
    Assignee: Horng Sheng Lih Enterprise Co., Ltd.
    Inventors: Hong-Tai Tsai, Hui-Ping Chou
  • Patent number: 6783146
    Abstract: The connecting device consists of a circular disk (7) fixed to the snowboard and fitting into a circular ring (8) holding the binding (1) on the board. The interior circular contour (11) of the ring into which the disk fits is eccentric relative to the exterior contour of the ring. The mechanical continuity provided by the ring guarantees that the binding will be held in position without high pressure needing to be exerted on this ring.
    Type: Grant
    Filed: November 27, 2000
    Date of Patent: August 31, 2004
    Assignee: Emery S.A.
    Inventor: Patrice Coing
  • Publication number: 20040089777
    Abstract: A surgical instrument support device and method for positioning a surgical instrument relative to a surface of a surgical support platform are disclosed. The support device includes a base member, an elongated support member, an extender bar, and a securing mechanism. The base member is fixably mountable to the surgical support platform. The elongated support member has one end mounted to the base member for pivotal movement of the elongated support member relative to the base member within a pivot plane that is nonparallel to the surface of the surgical support platform. The extender bar is adapted for mounting a surgical instrument with respect thereto and is disposed at the other end of the elongated support member. The extender bar projects from the elongated support member such that the pivotal movement of the elongated support member raises or lowers the extender bar and the surgical instrument mounted with respect thereto with respect to the surface of the surgical support platform.
    Type: Application
    Filed: November 7, 2002
    Publication date: May 13, 2004
    Inventors: Janice L. Schilt, William J. Kotelee
  • Patent number: 6663068
    Abstract: An improved structure beverage holder in which the mounting plate of the beverage holder has disposed in its back surface a recess having formed within spur gear teeth or other similar gear teeth and a through-hole, thereby enabling the fastening and emplacement of an oblique-faced conical block, a C-shaped mount, and a reverse C-shaped mount constituting a first type of mounting frame such that the beverage holder is installed to an appliance for utilization at an inclined state on a tube or a rod. Or, the fastening and emplacement only involves the C-shaped mount and the reverse C-shaped mount to constitute a second type of mounting frame such that the beverage holder is fixed and installed to an appliance in a vertical state. Respectively hinged at the inner sides of two clip arms on the beverage holder, arc-shaped retaining elements can be folded downward, but automatically return upward to their original horizontal state.
    Type: Grant
    Filed: September 10, 2001
    Date of Patent: December 16, 2003
    Inventor: Pei-Hsiu Huang
  • Patent number: 6614908
    Abstract: An adjustable apparatus holder used in a carrier and adapted to hold a personal electronic apparatus is disclosed to include a base panel, a first side plate slidably coupled to the base panel at one side, a second side plate pivoted to the base panel at an opposite side and held in a vertical position by springs, and a locking mechanism, which locks the first side plate when the second side plate is maintained in the vertical position, or unlocks the first side plate when the user tilts the second side plate.
    Type: Grant
    Filed: October 31, 2002
    Date of Patent: September 2, 2003
    Inventor: David Huang
  • Patent number: 6598841
    Abstract: The present invention provides a height adjustable table leg including an upper housing attachable to an underside of a table and being formed with an upper tubular portion. A lower tube member is dimensioned and configured to be telescopingly received by the upper tubular portion. A cam member is pivotably mounted to the upper tubular portion and selectively cooperates with an undulating strip attached to the lower tube member in one of a plurality of telescoped positions relative to the upper tubular portion.
    Type: Grant
    Filed: May 21, 2001
    Date of Patent: July 29, 2003
    Assignee: Hon Technology Inc.
    Inventors: Jason D. Erickson, Craig H. Schultz, Michael J. Bell
  • Patent number: 6598837
    Abstract: An infant nursing bottle holder includes a substantially U-shaped clamping member, a substantially Y-shaped nursing bottle-retaining member, a strap for securing an infant nursing bottle to the bottle-retaining member, multiple elongate members, interconnected end-to-end and, together, coupling the bottle-retaining member to the U-shaped clamping member, and a rotatable hinge joint at the interconnection of each pair of elongate members, each hinge joint having a geared resilient pivot that permits angular positioning of the joined elongate members at discrete arcuate intervals through a range of at least 180 degrees.
    Type: Grant
    Filed: December 6, 2001
    Date of Patent: July 29, 2003
    Inventors: Morris J. Howard, Evelyn L. Howard
  • Publication number: 20030111584
    Abstract: An assembly for hanging picture frames and other objects to a vertical support includes a base adapted to be mounted to the vertical support, a wheel supported by the base and rotatable on the base, and a hook rotatably coupled to the wheel and adapted to rotate upon rotation of the wheel relative to the base. The hook includes a hooked portion that receives an item to be mounted thereon.
    Type: Application
    Filed: February 7, 2002
    Publication date: June 19, 2003
    Inventors: Peter Kamenstein, Joseph P. Opramolla, Robert Howitt
  • Patent number: 6572060
    Abstract: An automatically collapsible prop for propping all kinds of loads such as golf bag, knapsack, coolie rack, etc., comprises a first tubular member having an upper end and an open lower end, a second tubular member relatively moveably inserted in the first tubular member so as to slide down by gravity relative to it to protrude from the open lower end of the first tubular member by a predetermined length when lifting the first member in a sloping or vertical position, and a third member rotationally mounted on a fixed shaft attached to the second tubular member so as to pivot relative to the first and second members about the fixed shaft. A first engaging groove is formed in the surface of the first member in the longitudinal direction to allow the second member with the third member to slide relative to the first member.
    Type: Grant
    Filed: March 6, 2002
    Date of Patent: June 3, 2003
    Assignee: Q-Boak Sports, Inc.
    Inventor: Kyung-Bun Yoon
  • Patent number: 6565060
    Abstract: An attachment stand frame for spa umbrella which includes a shaft supporting an awning thereon, wherein the attachment stand frame includes a stand base including a reinforcing panel extended therefrom adapted for mounting underneath an outdoor spa wherein the spa umbrella is uprightly supported on the stand base, and a supporting frame perpendicularly extended from the stand base for substantially attaching to the outdoor spa so as to securely mount the spa umbrella to the outdoor spa. The attachment stand frame further includes a base body, having a receiving chamber provided thereon, adapted to support the shaft, a rotor, which is rotatably disposed in the receiving chamber, having a rotor axial socket for inserting the shaft thereinto, and a locking arrangement for locking up the rotation movement of the rotor. Therefore, the attachment stand frame is adapted to be rigidly supported by the outdoor spa and rotatably mount the spa umbrella.
    Type: Grant
    Filed: February 27, 2001
    Date of Patent: May 20, 2003
    Inventors: Wanda Yiing Li, Raymond J. Carabotta
  • Publication number: 20020148937
    Abstract: The invention relates to a supporting construction for supporting an object, which supporting construction comprises two elements which are adjustable about an axis of rotation with respect to each other and which can be clamped together in a desired position. The two elements are provided with projecting ridges of conical section and with grooves in which said ridges are received, which ridges and which grooves extend concentrically about the axis of rotation and perpendicularly to an imaginary plane through said axis of rotation.
    Type: Application
    Filed: March 12, 2002
    Publication date: October 17, 2002
    Inventor: Rudolf Franciscus Andreas Obdeijn
  • Publication number: 20020125381
    Abstract: An automatically collapsible prop for propping all kinds of loads such as golf bag, knapsack, coolie rack, etc., comprises a first tubular member having an upper end and an open lower end, a second tubular member relatively moveably inserted in the first tubular member so as to slide down by gravity relative to it to protrude from the open lower end of the first tubular member by a predetermined length when lifting the first member in a sloping or vertical position, and a third member rotationally mounted on a fixed shaft attached to the second tubular member so as to pivot relative to the first and second members about the fixed shaft. A first engaging groove is formed in the surface of the first member in the longitudinal direction to allow the second member with the third member to slide relative to the first member.
    Type: Application
    Filed: March 6, 2002
    Publication date: September 12, 2002
    Inventor: Kyung-Bun Yoon
  • Patent number: 6446923
    Abstract: A mounting apparatus includes a base and receptacle for receiving the base in a support surface. A mounting assembly for mounting a mobile device may be secured to the base. The mounting apparatus may be secured to a support surface with a securing member, such as a thumbscrew, using one hand. In an embodiment, the mounting apparatus includes a cylindrical base including a mounting hole and a bottom surface having a securing pin. The mounting apparatus also includes a mounting assembly and a receptacle that has a bottom surface and inner surface forming a cylindrical receiving portion having a mounting hole. When the base is inserted into the receiving portion of the receptacle and rotated, the securing pin is received in the securing hole and the bottom surface of the base contacts the bottom surface of the receptacle.
    Type: Grant
    Filed: February 18, 2000
    Date of Patent: September 10, 2002
    Assignee: Nokia Mobile Phones Ltd.
    Inventor: Jari Olkkola
  • Patent number: 6438882
    Abstract: A lighted flexible display device or sign, useful for advertising purposes, and having a battery supply mount. The display device herein is a lighted display and is constructed to be flexible in the presence of inadvertent bumping or deflection thereof. The mounting is resilient such that, when the deflecting force is removed, the sign springs back to its normal lateral position. The mount for the display device includes a battery supply, with such supply being electrically connected to the electrical circuit of the sign proper. This is accomplished by means of electrical leads passing through a deflection restoration spring, by such leads passing through a resilient tongue, or with connectors used in a spring-biased pivotal construction for connecting the battery supply to the electrical lighting circuit of the sign.
    Type: Grant
    Filed: March 6, 1995
    Date of Patent: August 27, 2002
    Inventor: Randy B. Reynolds
  • Publication number: 20020100852
    Abstract: This invention relates generally to the field of restraint systems. Specifically, it relates to clamp restraint systems to achieve the restraint of a particular object, which may be particularly applicable to systems requiring the various and frequent adjustment of the clamped object. More particularly, the invention may relate to clamping systems providing force optimization and direction, facilitating varying degrees of adjustment, and coordinated or varying adjustment of multiple clamped objects within a more complex construction or framework. The invention may be particularly applicable to systems for clamping particular support elements or parts of racks, shelves, stands, or desks, and more particularly, may be particularly applicable for music instrument stands or racks, bicycle stands, and dental racks and stands.
    Type: Application
    Filed: February 1, 2001
    Publication date: August 1, 2002
    Applicant: Ultimate Support Systems, Inc.
    Inventors: Donald H. Eason, Douglas A. Kempel, Robin R. Slaton
  • Patent number: 6422651
    Abstract: In a stepping mechanism for a vehicle seat, in particular for an automobile seat, with a gear and a pivoting pawl that is adapted for pivoting toward the gear and rotating the gear upon engagement, a friction spring is provided for raising the pawl from the gear.
    Type: Grant
    Filed: September 8, 2000
    Date of Patent: July 23, 2002
    Assignee: Keiper GmbH & Co.
    Inventors: Joachim Mühlberger, Kai Schumann
  • Patent number: 6324810
    Abstract: Retrofit connectors that secure together the outside sheathing and underlying structural members of wood-frame or masonry houses, preventing damage when subjected to lateral stresses from a hurricane, or transverse loads from an earthquake. The connectors have special bushings and bearing surfaces that tie the outside sheathing and underlying structural members together, but allow deflection, and transfer of energy to other structural members. Different embodiments of the connectors allow them to adapt to most wood-frame and masonry homes, and to most roof pitches.
    Type: Grant
    Filed: August 10, 1998
    Date of Patent: December 4, 2001
    Inventor: Thomas Thompson
  • Patent number: 6322032
    Abstract: A base assembly for a windshield sunshade of an automobile includes a base unit with an engagement portion, a pivot coupler with a coupling rod, a sunshade holder housing the coupling rod, and pivot members pivotally combining the pivot coupler with the engagement portion. An insertion block inserted through two insertion holes of sunshade holder and two opposite grooves of the coupling rod is adapted to limit against a spring within a cavity of the pivot coupler. Two opposite projecting ridges respectively positioned at two opposite sidewalls of the sunshade holder are engaged with two opposite engagement recesses of the base unit in a position.
    Type: Grant
    Filed: September 18, 2000
    Date of Patent: November 27, 2001
    Inventor: Shu-Chen Su
  • Patent number: 6296217
    Abstract: A movable body supporting mechanism supports a movable body (12, 42) to be moved in a direction orthogonal to a flat surface, on which a fixed member (11, 41) and the movable body are both mounted. The movable body supporting mechanism is provided with: a lever (13a, 13b, 46a, 46b) rotatably linked to the fixed member and the movable body; a movable body gear (18a, 18b, 52) mounted on the movable body at a side thereof opposed to the fixed member; and a pinion (14a, 14b, 44a, 44b) engaged with the movable body gear and driven in conjunction with the lever.
    Type: Grant
    Filed: September 28, 1999
    Date of Patent: October 2, 2001
    Assignee: Pioneer Corporation
    Inventors: Yuji Ikedo, Masamitsu Ohkawara, Kenjiro Oizumi, Katsuhiro Onodera, Hideo Ito
  • Publication number: 20010022336
    Abstract: This invention intends to provide a bracket for mounting an accessory to a vehicle body capable of simplifying installation work and eliminating connector coupling failure.
    Type: Application
    Filed: March 14, 2001
    Publication date: September 20, 2001
    Applicant: Yazaki Corporation
    Inventor: Masahiro Sawayanagi
  • Patent number: 6286738
    Abstract: A bicycle rack for carrying a bicycle adjacent the rear of a vehicle. The bicycle rack includes an adjustable frame assembly having a first frame member attached to a housing and a second frame member attached to a connecting member. The connecting member is rotationally coupled to the housing to allow relative pivotal movement between the first and second frame members. A locking member is disposed within the housing and selectively movable between a first position, in which the locking member engages the connecting member to impede relative rotational movement between the connecting member and the housing, and a second position, in which the locking member is disengaged from the connecting member to allow relative rotational movement between the connecting member and the housing. At least one support arm is coupled to the housing and configured for sliding and pivotal movement between a stowed position and an extended position in which the arm engages the housing to support a bicycle adjacent the vehicle.
    Type: Grant
    Filed: December 17, 1999
    Date of Patent: September 11, 2001
    Assignee: Yakima Products, Inc.
    Inventors: Duncan Robins, Joseph J. Settelmayer, Scott R. Allen
  • Patent number: 6196507
    Abstract: A clamp assembly for releasably securing a cab or other truck toppers to a pick-up truck box includes master and slave assemblies mounted to a transverse section of the sidewall of the cab and spaced-apart from each other. Each assembly has an engagement member pivotable between an operative position in which the engagement member extends beneath an inwardly extending flange of the sidewall of the truck box and abuts the undersurface of the flange, and an inoperative position in which the engagement member clears the flange. A set of worm and worm gear is provided in the master assembly and a worm gear shaft extends through the master and slave assemblies to drive the engagement members in the pivotal movement. The clamp assembly is operated using a rotating tool from inside of the cab so that unauthorized removal of the cab from the truck is prevented.
    Type: Grant
    Filed: November 1, 1999
    Date of Patent: March 6, 2001
    Inventors: Yvon Morin, Kenneth J. Morey
  • Patent number: 6189845
    Abstract: A tripod, in particular a mini tripod for mounting lockably a photographic apparatus, includes a platform, a base, and a plurality of legs. The joint between the platform and the base serves as a pivot whereby the platform can perform deviation within a limited distance. A through hole is provided to go through from one lateral side of the base to the other lateral side. An axial block 44 is fitted into one end of the through hole 21 for abutting a corresponding surface of the platform. The other end of the through hole is provided with a nut receiving recess and a left clutch receiving recess for receiving a nut and a left clutch, respectively. A right clutch is provided on a corresponding side of the platform. A rotary knob having a screw rod passes through the platform to screwably join the right clutch, the left clutch, and the nut. The rotary knob is turnable to drive the screw rod into the base so that the teeth of the left and right clutches inter-engage to achieve firm positioning of the platform.
    Type: Grant
    Filed: March 5, 1999
    Date of Patent: February 20, 2001
    Inventor: Amy Chen