77results about "Trap doors" patented technology

A flexible loft hatch insulation device as suitable to be used on all different types of loft hatches. Manufactured from a variety of different insulation materials including various waste streams. Application includes insulation as well as draught proofing.

The invention discloses a large self-balancing type safe and labor-saving cover plate device which is used for being arranged at a lifting opening of floor slabs, and a framework is arranged around the lifting opening. The large self-balancing type safe and labor-saving cover plate device comprises a pair of guide rails, multiple cover plates and a lifting device, wherein the guide rails are respectively arranged on two opposite sides of the lifting opening, one end of each of the pair of guide rails is connected with the framework in a pivoted mode, the multiple cover plates are movably supported on the pair of guide rails, and the cover plates have an unfolded state and a folded state. The lifting device is used for lifting and descending the other end of each of the pair of guide rails so that the multiple cover plates are enabled to be switched between the unfolded state and the folded state. According to the large self-balancing type safe and labor-saving cover plate device, through the change of the rotation angles of the guide rails relative to the framework, a purpose of adjusting the gravity centers of the cover plates is achieved, and therefore the heavy cover plates can be opened and closed through utilization of self weights of the cover plates without the need of any additional auxiliary devices, the manufacturing cost is lowered, the problem that long cover plates cannot be manufactured on the principle that the folded cover plates only rely on counterweight is solved, and the operation process is enabled to be simpler and more convenient.

A grate apparatus for covering a pit defined in a floor of a vehicle wash facility includes a plurality of rigid rung pieces having a first end, a second end, an upper surface and a lower surface. The rigid rung pieces are secured in generally parallel and spaced apart fashion by a plurality of flexible strap members. The flexible strap members are secured to each of the rung pieces by a plurality of fasteners. The grate apparatus is moveable between an unwound position where the first end of each of the plurality of rigid rung pieces rests on one of a pair of spaced apart rails located adjacent the pit and the second end of each of the plurality of rung pieces rests on the other of the pair of spaced apart rails and a wound position wherein the plurality of rung pieces and the plurality of flexible straps are oriented in generally coiled position around a centerline.

A molded access door assembly for an access opening in a wall or ceiling is provided including a molded frame having a frame channel to form the outside of the access door assembly, the frame channel having spaced apart exterior and interior walls joined at the top edge by a top wall and having a lip extending from the bottom edge of the inner wall into the interior of the molded access door assembly to define an opening. The lip provides a stop rest for the door in the closed position and has a means of attaching the access door assembly to the wall or ceiling. The assembly also includes a door having a top surface and a first part of a hinge assembly along one edge of the top surface which cooperates with a matching second part of the hinge assembly along one edge of the frame channel to allow the door to move between an open and a closed position.

The invention discloses a waterproof object lifting hole. The waterproof object lifting hole comprises a framework, cover plates, a guardrail, a cover plate joint waterproof device which is used for containing water that leaks from a joint of two adjacent cover plates, and a framework diversion trench which is used for containing and guiding water that leaks from connecting gaps between the framework, the cover plates and the guardrail, wherein the framework diversion trench is communicated with a cover plate diversion trench. The waterproof object lifting hole has the advantages of simple structure, easiness in realization and remarkable waterproof effect.

The invention discloses a hoisting hole. The hoisting hole comprises a cover plate and a guardrail and further comprises a linkage device. The guardrail is a folding mechanism, and the linkage device is respectively connected with the cover plate and the guardrail. While the cover plate is opened or closed, the guardrail is driven to be opened or closed through the linkage device. Production cost is saved, and the device is fast to operate and easy to obtain.

The invention described herein relates to a utility vault door, or access door, positionable between closed, partially opened, and fully opened orientations and including at least one compression spring lift-assist mechanism for countering the weight of the vault door when positioning between the various orientations. The door may be selectively locked in the partially opened orientation and opened sufficiently for the convenient ingress and egress of large equipment therethrough.

Cellar or bulk head doors having sidewalls are provided which are made of a polymer and which are strong, durable, attractive, virtually maintenance free, easily assembled, have connection and anchorage points which allow the door assembly to be used over a wide temperature range without damage to the polymer parts making up the assembly and which has an opening preferably in one or both of the sidewalls for inserts such as a window, louver, screen or blank and which insert may be easily changed without tools for the purpose of providing light, ventilation, or security. The doors also may be extended from the structure being enclosed using opposed vertical extenders mated with a horizontal extender.

The present invention relates to a device to assist the opening of a covering element pivotably mounted relative to an edge of a frame. According to the invention, an assistance cylinder (6) includes a hollow shaft (7), a guide pin (10) inserted in the hollow shaft (7) and of which the end thereof opposite the end wall (8) comprises a yoke (11), a spring (13) inserted in the hollow shaft (7) surrounding the guide pin (10) and mounted pre-stressed when unloaded between the end wall (4) of the hollow shaft (7) and the yoke (11) of the guide pin (10), and a means (14) secured to the end of the guide pin (10) and engaging with the end wall (8) of the hollow shaft (7) for keeping the pre-stressed spring (13) in the released state thereof. The invention is useful in the field of road systems.