Abstract: Apparatus for operation of a vehicle seat swivel or rotation mechanism are disclosed. A disclosed apparatus includes a cable assembly having a first end and a second end. The first end of the cable assembly is configured to be operatively coupled to a rotation mechanism of a vehicle seat. A release member is operatively coupled to the second end of the cable assembly so that the rotation mechanism is urged toward a locked condition in the absence of a force being applied to the release member by a person.

Abstract: An apparatus and method is disclosed for automatically maintaining the viewing angle of a first display, mounted to a second display, regardless of the viewing angle of the second display. In one embodiment, such an apparatus includes a first display and a pivot mechanism to connect the first display to a second display. The pivot mechanism enables the first display to pivot relative to the second display. An angle retention mechanism is provided to automatically maintain the viewing angle of the first display regardless of the viewing angle of the second display.

Abstract: A projector includes a main body, a lens unit and a lens cover. The main body includes a housing and a groove formed on a bottom face of the housing. The lens unit is provided to the main body. The lens cover is configured to cover the lens unit. The lens cover is further configured to be fitted to the groove so that the lens cover rotatably supports the main body.

Abstract: A display assembly for a retail product has a base and a platform adjustably mounted on an upper end of the base. The platform includes a lower housing which is pivotally supported in a cradle attached to the upper end of the base. The platform is pivotally mounted on the cradle by a pair of pivot pins, at least one of which is threaded to secure the platform in an adjusted titled position on the cradle. A plurality of notches are formed on the platform housing and selectively engage a detent formed on the cradle to retain the platform in an adjusted position. A sensor may be removably mounted on the platform and connected to the product and to the base by an expandable cord to actuate an alarm if the product is removed in an unauthorized manner from the sensor or base.

Abstract: An adapter is provided for mounting a wind turbine on the upper end of a wind turbine tower even though the yaw plate of the wind turbine is not complementary in shape to the upper end of the wind turbine tower.

Abstract: A rotation mechanism of a television includes a rotation unit, a box, a frame which is connected on the box and connected with the television, and a driving unit. The driving unit has a stationary fan-shaped rack with a positioning rod and a pivot. The rack is connected to the rotation unit and box is rotated about the rack when the driving unit is activated so that the rotation unit and the frame are rotated. By this arrangement, the television is rotated with the rotation unit.

Abstract: A directional support structure for use with solar panels, flat satellite antennas, and the like items that are directed toward a point in space. The support structure includes a mounting plate with an extension tube extending outwardly therefrom, pivotally secured to a mounting bracket permitting rotational azimuth alignment of the mounting plate. At least one locking turnbuckle is attached between the extension tube and the mounting bracket to provide locking and vertical adjustable alignment of the mounting plate. The base member includes an attached first flange positioned along an upper end of the base member, an attached flaring positioned on the lower end of the mounting bracket, and an unattached second flange positioned over the flaring, securable to the first flange with fasteners.

Abstract: An apparatus and method is disclosed for automatically maintaining the viewing angle of a first display, mounted to a second display, regardless of the viewing angle of the second display. In one embodiment, such an apparatus includes a first display and a pivot mechanism to connect the first display to a second display. The pivot mechanism enables the first display to pivot relative to the second display. An angle retention mechanism is provided to automatically maintain the viewing angle of the first display regardless of the viewing angle of the second display.

Abstract: A display apparatus includes a stationary base portion and a support member mounted to a top surface of the stationary base portion. A vertically extending pole is disposed through the interior of each of the support member and the base portion along a center axis, thereby permitting selective rotation of the support member. The support member includes a plurality of lateral side panels for displaying graphic and or other materials, such as photographs and advertising. The vertically extending pole permits electrical leads to be routed therethrough to connect, for example, to at least one light source.

Abstract: A stand (3) for a surgical microscope comprising at least one vertical rotary bearing (4). A pivot arm (5) is mounted rotatably in the rotary bearing (4). An electromagnetic brake (6) for blocking the pivoting motion of the pivot arm (5) in the rotary bearing (4) is provided. A mechanical brake (7) with adjustable braking force is additionally present for braking the pivot arm (5) in the rotary bearing (4).

Abstract: A 360 degree swivel cushion for bathroom encompassing a rotating device having a base plate, a ball bearing plate and a rotating plate disposedly configured between a lower fixed pad and an upper rotating pad. A plurality of stainless steel ball bearings atop the ball bearing plate are used to rotate within a large circular track and a small circular track of the rotating plate. Upon a mobility handicapped person sitting atop the cushion, the body can be rotated by merely swaying the body left and right, which thereby conveniences a family member or a house keeper to assist bathing and cleaning the body of the mobility handicapped person. Waterproof antiskid pads covering the rotating pad and the fixed pad not only provide for comfortable sitting and prevent slipping; moreover, both upper and lower surfaces are available for use.

Abstract: A rotatable book holder includes a housing having a chamber to rotatably receive a rotary member which has a number of holes. A pole includes a lower portion secured to the rotary member, and a plate is secured to an upper portion of the pole and includes a number of holes facing toward the holes of the rotary member, to receive shanks of books, and for allowing the books to be rotated relative to the housing in concert with the rotary member, and thus for allowing the books to be easily viewed or read by the users. The housing includes a weight to rotatably support the pole and to increase stability of the housing.

Abstract: The invention concerns a stand (1) for a surgical microscope, having a stand column (2) and having at least one pivot arm (3). The pivot arm (3) is arranged pivotably about a vertical rotation axis (5) by way of a rotary bearing (4). A tilting device (6) for adjustably tilting the rotation axis relative to the column is provided, wherein the tilting device (6) includes a bearing shaft (8) supported by the column and defining a substantially horizontal tilting axis, and an adjustment housing (7) mounted on the bearing shaft (8) for rotation about the tilting axis. The rotary bearing (4) is carried by the adjustment housing (7).

Abstract: The invention concerns a stand (1) for a surgical microscope, having a stand column (2) and having at least one pivot arm (3). The pivot arm (3) is arranged pivotably about a vertical rotation axis (5) by way of a rotary bearing (4). A tilting device (6) for adjustably tilting the rotation axis relative to the column is provided, wherein the tilting device (6) includes a bearing shaft (8) supported by the column and defining a substantially horizontal tilting axis, and an adjustment housing (7) mounted on the bearing shaft (8) for rotation about the tilting axis. The rotary bearing (4) is carried by the adjustment housing (7).

Abstract: The invention concerns a stand (3) for a surgical microscope comprising at least one vertical rotary bearing (4). A pivot arm (5) is mounted rotatably in the rotary bearing (4). An electromagnetic brake (6) for blocking the pivoting motion of the pivot arm (5) in the rotary bearing (4) is provided. A mechanical brake (7) with adjustable braking force is additionally present for braking the pivot arm (5) in the rotary bearing (4).

Abstract: An apparatus is provided for removably mounting an electronic device to a surface and for positioning the device with respect to the surface. The apparatus includes a cradle securable to the electronic device and a pivot link, which has a first end and a second end. The first end being pivotally coupled to the cradle. The apparatus also includes a support having a mounting pedestal coupled thereto. The second end of the pivot link is pivotally coupled to the support. The apparatus has a base which has a lower face that can be coupled to the surface and an upper face. The upper face has a receiving slot for the pedestal, the slot having a shoulder extending thereabove to engage the pedestal. The slot further has an open end to allow the pedestal to be moved within the slot. The base further includes a releasable locking arm having a retaining ridge located in line with the open end of the slot to selectively hold the pedestal within the slot.

Abstract: The present invention is an emplacement stand for holding explosive ordnance disposal tools that comprises a support base having tapered pegs evenly spaced around the outside of the support base extending outward at a downward angle. Detachable legs may be attached to the tapered pegs or each other to increase the height of the support base. A pivot arm slides through a hollow bearing ring within the support base and a set screw connector locks the pivot arm into a specific desired position after moving the pivot arm up or down within the support base. A pivot base, having a tool cradle connected to a disc shaped surface attaches to a clevis slot within the pivot arm through a pin that allows the disc shaped surface to freely pivot about the pin within the slot. A second set screw connector locks the disc shaped surface into place within the clevis slot.

Abstract: A rack is designed to hold a plurality of pistol nozzles and is formed of a base and a displaying frame. The base is rested on the floor surface and is provided with a support rod on which the displaying frame is supported such that the displaying frame can be revolved and adjusted in height.

Abstract: An apparatus is provided for removably mounting an electronic device to a surface and for positioning the device with respect to the surface. The apparatus includes a cradle securable to the electronic device and a pivot link, which has a first end and a second end. The first end being pivotally coupled to the cradle. The apparatus also includes a support having a mounting pedestal coupled thereto. The second end of the pivot link is pivotally coupled to the support. The apparatus has a base which has a lower face that can be coupled to the surface and an upper face. The upper face has a receiving slot for the pedestal, the slot having a shoulder extending thereabove to engage the pedestal. The slot further has an open end to allow the pedestal to be moved within the slot. The base further includes a releasable locking arm having a retaining ridge located in line with the open end of the slot to selectively hold the pedestal within the slot.

Abstract: A seat assembly including a vehicle seat and a system for rotating a vehicle seat are provided wherein the system is designed to carry integrated seat restraint loads. The seat includes a base having a lower base section and an upper base section which supports the vehicle seat on an upper surface thereof. A reversible DC motor and a transmission including a drive screw are supported on the lower base section. A flexible cable couples an output shaft of the DC motor to the drive screw which rotates about a horizontal axis upon actuation of the DC motor. The transmission also includes a drive nut threadedly mounted on the drive screw to move along the substantially horizontal axis upon actuation of the motor. The transmission further includes a link coupled to the upper base section and the drive nut to transmit linear motion of the drive nut to rotary motion of the upper base section.

Abstract: An improved rotational cake decorating apparatus, commonly known as a Lazy Susan, used in the decoration, display and service of cakes. Said improved rotational cake decorating apparatus has a novel gripping means disposed thereon for improved rotational control. A donut shaped apparatus with a novel gripping means disposed thereon to be fixably attached to an existing rotational cake decorating apparatus. Said donut shaped apparatus with said novel gripping means provides for improved rotational control of said existing rotational cake decorating apparatus. A radial extension apparatus with a novel gripping means disposed thereon that can be removably attached to an existing rotational cake decorating apparatus. The radial extension apparatus provides a larger surface for supporting a work product such as a cake whereby the surface for supporting a cake on the existing rotational cake decorating apparatus is increased allowing for the decoration of larger cakes.

Abstract: A base assembly of indifferent equilibrium. The base assembly includes a stationary member, a rotatable member and a constant-force spring. The rotatable member is rotatably mounted on the stationary member. The constant-force spring member has an end portion connected to the rotatable member and a coiled portion connected to the stationary member, wherein a restoring force of the constant-force spring member is equal to a frictional force between the stationary member and the rotatable member.

Abstract: The present invention is a wheelchair swivel platform that allows a standard, unmodified wheelchair or other non-swiveling chair and an occupant to swivel about an area of a workstation, in much the same way as a modem swivel office chair. The wheelchair swivel platform includes a top plate 16 and a bottom plate. The bottom plate serves as a base for the platform which lies on the floor to support the top plate 16. The top plate 16 swivels about the bottom plate while supporting the wheelchair. A rotation locking device prevents rotation of the platform during positioning of the wheelchair on and off the platform.

Abstract: A seat assembly featuring a seat support assembly having a seat mount assembly and a pedestal post assembly which pivotally supports the seat mount assembly and includes a first component and a second component with the second component being adjustable in height with respect to the first component. The seat support assembly includes a rotation locking assembly with a releasable rotation lock which locks the seat mount assembly from rotating with respect to the pedestal post assembly. Also included is a rotation prevention device or arrangement that is supported by the pedestal post assembly and acts to prevent relative rotation between the first and second components while not interfering with height adjustability between the first and second components. In a preferred embodiment, the first and second components are part of a fluid spring system which has an air spring that varies in height by way of a fluid cushion.

Abstract: A video display stand having dual panning axes suitable for controlling a screen direction of appliances such as a TV set or a personal computer without bumping against a wall even in a state that it is positioned very closely to the wall, and its controlling method for automatically controlling screen directions by using a driving force, including two motors being installed having gear driving shafts at one side of either a rotational base or a rotation support member of the TV set; two movement guide toothed slots each being formed along a circular arc centering a mutually opposite gear driving shaft with a predetermined width and depth, at the opposite side corresponding to the position of each motor, and having a gear portion to be engaged with the gear driving shaft at one side of each wall; and a controller for controlling driving of the motors.

Abstract: A swivel device intended for electronic equipment and having an upper platform that rotates upon a stationary base. The platform is elevated above the base by means of supports, creating a low profile wiring cavity with a cable supporting bottom surface. The cables from the electronic equipment are passed through the cavity in a manner that controls and protects them. In addition, a post located within the wiring cavity controls the cable path so that the cables are not pulled, entangled, or disconnected during rotation of the platform.

Abstract: A seat mounting assembly to rotate a seat in a segment of an inclined rotational plane. The assembly rotates at a predetermined angle with respect to the direction of the force of gravity to bank the seat upward as it traverses to either the left or the right. The seat mounting assembly is constructed and arranged to receive a seat and to be mounted in a vehicle, such as a boat. An anti-rotational assembly is provided to control the rotational speed and the segment within the rotational plane in which the assembly reciprocates.

Abstract: A variable position mailbox comprising an automatically controlled mailbox support structure for translating a mailbox through a series of preset positions including a night storage position, a mail delivery position, and a mail pick-up position such that mail may be retrieved safely and conveniently by the homeowner away from the traffic bearing road, and the mailbox may be conveniently stored in a position away from the road during the nighttime to discourage vandalism.

Abstract: An apparatus is provided for removably mounting an electronic device to a surface where such mounting can be accomplished using only one hand. The apparatus includes a mounting bracket that is securable to the electronic device. The bracket has a mounting pedestal coupled to it which has a lower ratchet surface. The apparatus further has a base which has a lower face that can be coupled to the surface, and an upper face which has a receiving slot for the pedestal. The slot has a shoulder extending thereabove to engage the pedestal, and an open end that allows the pedestal to be moved within the slot. The base further includes a releasable locking arm which has a retaining ridge located in line with the open end of the slot to selectively hold the pedestal within the slot. The locking arm has an upper pawl surface located to engage the ratchet surface when the pedestal is located within the slot.

Abstract: An adjustable television stand is provided including a base fixedly positioned on a recipient surface. Also included is an intermediate portion slidably situated on the base along a vertical axis. An upper support is rotatably coupled to the intermediate portion about a vertical axis and further tiltable about a horizontal axis. A plurality of mechanisms are provided for selectively raising and lowering the intermediate portion and further rotating and tilting the upper support.

Abstract: A screw spindle of a swivel chair according to the present invention comprises a spindle which is placed in an outer case; an elastic body which is placed in the spindle; a bearing support which is placed in the spindle; a ball bearing component which is placed in the spindle; a screw nut and a clutch, each having a corresponding furrow and ridge with curved surfaces, which are placed in the spindle; a screw shaft which is placed in the spindle; a fixer and a clip which hold the screw shaft in place; and a stopper which is formed at the screw shaft and limits the height of the seat; a spindle bushing located between the screw shaft and the elastic body. The screw shaft further includes an idling protection component and a fixing end, and the fixer includes an idling protection hole corresponding to the idling protection component.The screw spindle of the present invention has the following advantages.

Abstract: Adjustable-height column, especially for chairs, includes a guide tube and a pneumatic, selectively blockable piston-cylinder unit for height adjustment located in the guide tube. The piston sealingly subdivides the cylinder into two operational chambers. Beginning at a defined retracted setting of the piston-cylinder unit, the blocking function is compulsorily canceled, in that a fluid flow connection between the two operational spaces is established which overrides the blocking function. An additional spring element is placed in series with the piston-cylinder unit to prevent a sudden collapse of the column.

Abstract: A flat panel display device that rotates smoothly in a horizontal direction and has a wide swiveling angle for easy adjustment of a visual angle. The flat panel display device includes a display unit that has a flat panel for displaying an image, and a stand to support the display unit, with a circular recess located at a top portion of the stand. A hinge member connects the display unit to the stand and includes a ring-shaped rotation member. The rotation member has a first portion and a second portion, with the second portion positioned below the first portion. The second portion has an inner diameter smaller than an inner diameter of the first portion, and two stoppers are positioned in the second portion. A holder is fixed to the circular recess of the stand to secure the rotation member within the stand. The holder includes two claws that are engaged to a bottom surface of the rotation member, and a protrusion member, formed at an outer circumference of the holder, to come in contact with the stoppers.

Abstract: A moveable support arm for a mailbox which includes a cylindrical cap which is sized to fit over a vertical support post. The cap has an open bottom and a closed top with a horizontal support member being attached to said cap, and containing means to attach and support a horizontal post in fixed engagement.

Abstract: A video display support includes a support arm having an air cylinder suspended on the inside, a bottom plate and a mounting assembly coupled to the support arm at one end, a video display mount coupled to the support arm at an opposite end through an X-axis adjustment connector and a Y-axis adjustment connector, and a angle adjustment structure coupled between the support arm and the bottom plate, wherein the angle adjustment structure includes a holder frame coupled between the support arm and the bottom plate, a shaft rotatably mounted in the holder frame, a locating frame mounted in the holder frame, a slide mounted on the locating frame and coupled to the piston rod of an air cylinder and moved in direction perpendicular to the shaft, and an adjustment screw inserted into an elongated slot at the holder frame and threaded into a screw hole at the shaft and a screw hole at the slide to secure the shaft and the slide together.

Abstract: A rotatable and transferable stanchion assembly includes an elongate body having an upper end portion adapted to receive and secure thereto an accessory, and a lower end portion. A cap is mounted on the lower end portion of the body and has a lower portion with an outer external surface. A location plate, which is fastened to a flat surface, has a socket formed therein shaped for receiving the lower portion of the cap. A stud and bolt assembly secure the cap to the location plate in such a position that the lower portion of the cap is disposed within the socket of the location plate wherein the body and cap are adapted to rotate relative to the location plate. A locking plate of the present invention rotatably locks the elongate body and cap in place with respect to the location plate at a desired angle of rotation.

Abstract: A security mounting assembly for an electrical appliance, such as a color television monitor, includes a mounting ring which may be attached to a flat mounting surface by a series of fasteners. The mounting ring includes glide members disposed thereon radially outwardly of the fasteners and the mounting ring is captured between two flanges attached to a flat support tray. The support tray is attached to the television with fasteners and swivels in place upon the attachment ring.

Abstract: A roadside standard assembly and maintenance method are provided which facilitate installation, maintenance, and repair of an object suspended over a roadway. The standard assembly comprises a support pole and an arm extending from the pole. The object is supported on the arm, and is normally disposed over a roadway. The standard rotates about the pole, allowing the arm to swing from over the roadway to a roadside position from which the object can be accessed for maintenance without resorting to a road closure. An anchoring structure maintains the upward orientation of the pole, and is optionally retrofittable for existing roadside standard installations.

Abstract: A height adjusting device for a chair consists of an inner tube having a top end fixedly connected to a chair seat and a bottom end fixedly connecting with a bushing, a positioning tube extending upwardly from a chair base, having an upper end mounted with a sleeve for receiving the inner tube and a base plate defining a plurality of downward protrusions, a screw having a threaded upper section for threadedly engaging with the bushing and a reduced lower section defining an annular stepped edge and a bottom end extending through the base plate to fixedly attach with an engaging member defining a plurality of upward protrusions for releasably engaging with the downward protrusions of the base plate, the threaded upper section of the screw defining a top projection and a bottom projection for limiting the traveling of the bushing therealong, a spring and a bearing assembly being mounted around the reduced lower section of the screw and located between the base plate and the threaded upper section of the screw.

Abstract: A combination toy and stool is provided that rotates and simultaneously lowers when a child sits on the seat. When the seat lowers fully, the invention can be used as a stool. The invention includes a stool seat that has a helically grooved or twisted central shaft extending below the seat, and a plurality of support shafts spaced about the central shaft also extending below the seat. The seat sets onto a pedestal that incorporates an upper and a lower member that rotate relative to each other similar to a "lazy susan". The upper pedestal member has a plurality of upward extending tubular members that receive the support shafts that extend below the seat. The lower pedestal member has an upward extending central shaft that extends through the center of the upper pedestal member and receives the twisted central shaft of the seat in a vertical aperture in the central shaft.

Abstract: A kind of SWIVEL AND SLIDE assembly including a Slide Base, Swivel Part, Slide Part, Lock Part, and Channels at both sides of the Slide Base. The Swivel Part includes a first Swivel Base and a second Swivel Base. The first Swivel Base includes the Slide Feet extending into the Channel, the female circle of the Ring Part, the Lunar Groove and the Pedestal. The second Swivel Base includes the male circle of the Ring Part, the Lunar Groove and the Swivel Lock Slots. Overlapping of the male circle and female circle is fixed by the rolling balls. By installing a Lock matched with the Lock Slot the swiveling can be started or stopped. This invention provides well distributed pressure when swiveling, easy operation, and reliable lock.

Abstract: The present invention is related to a hub for a rotatable chair, said hub comprising an essentially pyramidal body having its side faces (1) suited for the mounting of the chair's leg element (2) thereon and further including a centrally aligned cylindrical cavity (3) suited for accommodating the center rod (4) of the chair seat cushion. The hub is characterized in that the lower part of each side face (1) is flared outwardly forming a slanting flank (5) with at least one hole (6) suited to accommodate a fixing screw (7) adapted to be screwed from underneath the hub into each leg element (2), and that each side face (1) further includes an essentially radially projecting support element (8) adapted for insertion into a mating groove (9) provided to each leg element (2).

Abstract: An apparatus for self-administering fluids in patients, children, and persons of limited capabilities, includes a base, a first generally cylindrical, elongate support that extends upwardly from the base, a second generally cylindrical, elongate support that extends generally upwardly from the first support. The second support is pivotable relative to the first support and assumes first and second positions. The second support in the first position and the first support extend generally in a common direction. The second support in the second position extends generally perpendicular to the first support. The second support is rotatable a complete revolution about the first support.

Abstract: A stand assembly for supporting a cylinder head having a threaded spark plug aperture, includes a base for stabilizing the stand assembly and a pivot clamp with a removable mandrel having a threaded end that engages the threaded spark plug aperture of the cylinder head.

Abstract: Disclosed is a pedestal base for furniture, such a chair. The pedestal base is comprised of a plurality of radially oriented leg members which converge on a central hub, the hub and all of the leg members being formed as an integral piece of molded plastic. The central hub has an upper portion which is adapted to receive a plastic bushing and a lower molded portion which in combination with the bushing holds a chair seat height adjustment mechanism, such as a pneumatic cylinder. The chair base is lightweight and less expensive to manufacture than prior metal and wood chair bases.

Abstract: A chair including a seat and a back, the back including a pair of parallel guide plates protruding from a rear surface thereof, each guide plate having a longitudinal groove. The seat and back are supported by first and second front legs and first and second rear legs, and a transverse part extends between the first and second front legs. The transverse part includes a top head portion including two guide tips respectively slidably received in the longitudinal grooves of the guide plates. Additionally, a height adjusting device is provided, including at least one casing slidably mounted on the first front leg, the casing including an operating element having a protrusion adapted to engage recesses formed in the first front leg of the chair.

Abstract: An armrest assembly for attachment to a chair includes a base plate. The base plate can be secured, in a chair of the type including a (i) seat bottom cushion on which a person can sit, (ii) a pedestal assembly supporting the seat bottom cushion, and (iii) a plurality of fasteners securing the pedestal assembly to the underside of the seat bottom cushion, between the seat bottom cushion and the pedestal. The base plate has a plurality of fastener openings equal in number to the number of fasteners in the chair to which the armrest assembly is to be attached. The fastener openings are arranged in the same pattern as the fasteners in the chair to which the armrest assembly is to be attached. The base plate can have at least two sets of fastener openings arranged in different patterns, whereby the base plate can selectively be secured intermediate the pedestal assembly and the seat bottom cushion of at least two different chairs having different fastener patterns.

Abstract: A rotatable seat mounted on a floor includes a seat proper, a lower base member mounted on the floor, an upper base member mounting thereon the seat proper and a retaining member for retaining the upper base member on the lower base member. The lower base member has a first annular portion. The upper base member has an annular flange portion and a second annular portion which is truncated conical in shape. The annular flange portion is rotatably put on the first annular portion such that the upper base member is rotatable relative to the lower base member. The retaining member is secured to the lower base member and has third and fourth annular portions. The third annular portion is opposed to and spaced from the first annular portion such that an annular groove for receiving therein the annular flange portion is defined therebetween.

Abstract: A rotatable and removable bed tray for institutional or private home use. The bed tray is easily adjustable by the bedridden patient or by others. Further, there is provided bed rail adaptor for adopting beds without bed rails to use the bed tray.

Abstract: A lever operated clamping mechanism for adjustably engaging and locking in position structural members comprising two shoulder bolts and a disk spring for attaching and slidably guiding a slotted structure member relative to a fixed support structure. A threaded lever engages one of the shoulder bolts for frictionally locking the position of the structural member relative to the support structure. The device acts as a positional clutch permitting substantially firm frictional engagement of structural members when the lever is in one position and firm yet slidable engagement of the structural members when the lever is in another position.