A retractable door sill, including: a mounting base, the mounting base including an upper fixing base and a lower fixing base; a rotating drum, the rotating drum being arranged between the tipper fixing base and the lower fixing base, a partition cloth, a torsion spring being configured to make the rotating drum rotate in one direction around its axis, the rotating drum wind up the partition cloth; and an adjusting device, the adjusting device comprising an adjusting rod and an adjusting mechanism, one end of the torsion spring being connected to the rotating drum, the other end of the torsion spring being connected to the adjusting rod of the adjusting device, the adjusting mechanism being configured to enable the adjusting rod to rotate unidirectionally around its own axis, and the adjusting rod being configured to change a torsional deformation of the torsion spring through its own rotation.

A retractable door sill, including: a mounting base, the mounting base including an upper fixing base and a lower fixing base; a rotating drum, the rotating drum being arranged between the tipper fixing base and the lower fixing base, a partition cloth, a torsion spring being configured to make the rotating drum rotate in one direction around its axis, the rotating drum wind up the partition cloth; and an adjusting device, the adjusting device comprising an adjusting rod and an adjusting mechanism, one end of the torsion spring being connected to the rotating drum, the other end of the torsion spring being connected to the adjusting rod of the adjusting device, the adjusting mechanism being configured to enable the adjusting rod to rotate unidirectionally around its own axis, and the adjusting rod being configured to change a torsional deformation of the torsion spring through its own rotation.

A system for exerting torque on a shaft includes: a spring assembly having; a spring; a companion member to the spring, wherein at least one of the spring and the companion member is in compression and the other of the spring and companion member is in tension; connecting structure for transmitting a force associated with the spring outside of the gear assembly; and a gear train for connecting the connecting structure to the shaft to apply torque to the shaft. A method of exerting torque on a shaft includes: arranging a plurality of spring assemblies arranged in an array around the shaft, each spring assembly having; a spring; connecting structure for transmitting a force associated with the spring; attaching a gear train to the connecting structure; and configuring the gear train to apply the force associated with the spring to the shaft in the form of torque on the shaft.

A system for exerting torque on a shaft includes: a spring assembly having; a spring; a companion member to the spring, wherein at least one of the spring and the companion member is in compression and the other of the spring and companion member is in tension; connecting structure for transmitting a force associated with the spring outside of the gear assembly; and a gear train for connecting the connecting structure to the shaft to apply torque to the shaft. A method of exerting torque on a shaft includes: arranging a plurality of spring assemblies arranged in an array around the shaft, each spring assembly having; a spring; connecting structure for transmitting a force associated with the spring; attaching a gear train to the connecting structure; and configuring the gear train to apply the force associated with the spring to the shaft in the form of torque on the shaft.

A retractable curved door assembly includes a spring-loaded roller assembly having a reel structure configured to rotate about an axis of rotation thereof, a rail extending away from the spring-loaded roller assembly in a direction perpendicular to the axis of rotation of the reel structure with at least a portion of the rail curving about an axis arranged parallel to the axis of rotation of the reel structure, a door end structure slidably engaging the rail, a flexible screen coupled to the reel structure and to the door end structure, and a tension element coupled to the reel structure and the door end structure. A greater tensile force is applied to the tension element than to the flexible screen when the door end structure is slid along the rail in a direction away from the spring-loaded roller assembly to prevent buckling of the flexible screen.

The Invention relates to the field of roller shutter, discloses the automatic landing or rising type roller shutter, the main point of its technical solution is to include the shell, the shell is set with a disc, the side of the shell is set with an extension tube, the side of the disc is set with an extension body, at least part of the extension body extends into the extension tube, through the user pulling the rope body, drive the roller shutter rise or fall, in each with any start-stop structure or can advance to apply the force of the spring roller shutter. The rope body is provided with a pull rod in the part of the rope body that extends out of the shell, and the rope body is pulled by the pull rod to facilitate the user's grip and prevent the rope body from knotting and other situations.

The Invention relates to the field of roller shutter, discloses the automatic landing or rising type roller shutter, the main point of its technical solution is to include the shell, the shell is set with a disc, the side of the shell is set with an extension tube, the side of the disc is set with an extension body, at least part of the extension body extends into the extension tube, through the user pulling the rope body, drive the roller shutter rise or fall, in each with any start-stop structure or can advance to apply the force of the spring roller shutter. The rope body is provided with a pull rod in the part of the rope body that extends out of the shell, and the rope body is pulled by the pull rod to facilitate the user's grip and prevent the rope body from knotting and other situations.

A spring roller blind which can be started and stopped at will, including a transverse rod and a chuck, wherein the transverse rod is fixedly connected to the chuck, a first torsion spring is arranged on the transverse rod, and one end of the first torsion spring is fixedly connected to one end of the transverse rod away from the chuck. When pulled downwards, the roller blind can be stopped at any position by the friction between embracing springs and a pipe plug; and when a pull ring is pulled, the roller blind can be retracted automatically under the action of the restoring force of the first torsion spring.

A spring roller blind which can be started and stopped at will, including a transverse rod and a chuck, wherein the transverse rod is fixedly connected to the chuck, a first torsion spring is arranged on the transverse rod, and one end of the first torsion spring is fixedly connected to one end of the transverse rod away from the chuck. When pulled downwards, the roller blind can be stopped at any position by the friction between embracing springs and a pipe plug; and when a pull ring is pulled, the roller blind can be retracted automatically under the action of the restoring force of the first torsion spring.

The present disclosure belongs to the field of spring roller shutters, and particularly relates to a spring roller shutter with adjustable function, which comprises a spring assembly in a drum, an adjusting assembly and a limiting assembly, wherein one end of the drum includes a concentric adjusting cylinder, the adjusting cylinder is connected with an output end of the spring assembly, one end of the adjusting cylinder away from the drum includes a fixed shell, the fixed shell includes a cavity with an opening facing the adjusting cylinder, the one end of the adjusting cylinder slides in the fixed shell, and the adjusting assembly and the limiting assembly are in the fixed shell, thereby achieving the benefit of adjusting the maximum withdrawal height of the curtain.