A linear extension and retraction mechanism that is mounted in a robot arm mechanism includes: a plurality of first pieces having a flat plate shape which are bendably connected to each other at front and rear end faces; a plurality of second pieces having a groove shape which are bendably connected to each other at front and rear end faces of a bottom part, with the first and second pieces becoming linearly rigid when superposed, and the first and second pieces returning to a bent state when separated from each other; a head section which joins a leading first piece of the plurality of first pieces and a leading second piece of the plurality of second pieces; and a sending-out mechanism section including a plurality of rollers and for firmly superposing the first and second pieces and supporting the first and second pieces movably to front and rear. At least one groove section that extends from front to rear is formed in the surfaces of the first and second pieces that contact the rollers.

A linear extension and retraction mechanism that is mounted in a robot arm mechanism includes: a plurality of first pieces having a flat plate shape which are bendably connected to each other at front and rear end faces; a plurality of second pieces having a groove shape which are bendably connected to each other at front and rear end faces of a bottom part, with the first and second pieces becoming linearly rigid when superposed, and the first and second pieces returning to a bent state when separated from each other; a head section which joins a leading first piece of the plurality of first pieces and a leading second piece of the plurality of second pieces; and a sending-out mechanism section including a plurality of rollers and for firmly superposing the first and second pieces and supporting the first and second pieces movably to front and rear. At least one groove section that extends from front to rear is formed in the surfaces of the first and second pieces that contact the rollers.

A linear expansion mechanism includes: a plurality of linear-motion mechanisms assembled in series; a block train including a plurality of blocks coupled to each other in a row, a block at a leading end being connected to a linear-motion mechanism at a leading end; and a housing part that houses the block train. The housing part has a pair of arc-shaped rails and that being separately arranged on opposite sides of the block train, and a pair of projection bodies to be engaged with the pair of arc-shaped rails are provided on opposite side faces of each of the blocks.

A robot apparatus includes a base, a strut unit, and a linear expansion mechanism 1 rotatably supported on the strut unit. The linear expansion mechanism includes: a plurality of cylindrical bodies assembled in series to each other; a block train including a plurality of blocks coupled to each other in a row, the block at the leading end being connected to the cylindrical body at the leading end; and a housing part that houses the block train along an arc-shaped trajectory, the housing part being arranged below the cylindrical body at the trailing end and above the strut unit.

A scissor lift (100) for use in a stage assembly includes a base portion (110) configured to be supported on a floor or other support surface and a top portion (120) configured to support a platform. A scissor arm assembly (130) connects the base portion (110) and the top portion, and a rigid chain lifting system (150) comprising a rigid chain (151) connecting the base portion (110) and the top portion (120). Extension and retraction of the rigid chain (151) causes the top portion (120) to rise and fall with respect to the base portion (110). The use of a rigid chain lifting system (150) means that the scissors (130) are provided for guidance rather than applying load. The scissor lift (100) can be used in conjunction with one or more passive scissors (200), couplable to the scissor lift (100).

Disclosed is a tracked lifting platform for vehicles (14), comprising at least two tracks (16), wherein each track (16) engages at least at a respective end region of a lifting platform (18) for lifting and lowering the track (16) between a basic position (19) and a working position (21), wherein the lifting platform (18) comprises a push column (21) with multiple push members (23), which can be arranged one above the other so as to be resistant to pressure in the vertical direction.

A rigid drive chain comprises a plurality of links connected end-to-end. The links have a block end including a pair of receptacles, a driving face and a driven face. The links have a connector end including a tongue. The block end and connector end are one-piece members that include a plurality of gear teeth along one side of both the block end and connector end. A plurality of protrusions or pins connect the tongues to the receptacles. The links are adapted to be pivoted by a driving gear between a driving orientation of the links with the driving face engaging the driven face of an adjacent link in a forward direction.

A rigid drive chain comprises a plurality of links connected end-to-end. The links have a block end including a pair of receptacles, a driving face and a driven face. The links have a connector end including a tongue. The block end and connector end are one-piece members that include a plurality of gear teeth along one side of both the block end and connector end. A plurality of protrusions or pins connect the tongues to the receptacles. The links are adapted to be pivoted by a driving gear between a driving orientation of the links with the driving face engaging the driven face of an adjacent link in a forward direction.

Described is a chain including a plurality of links pivotally connected to each other such that the chain is configured to bend in one direction without back-bending. Each of the plurality of links including a link body include: an inner side facing a bending direction of the chain; an outer side facing opposite the bending direction of the chain; a back-bending prevention portion; a post feature extending laterally across the link body, and a connection feature configured to engage with the post feature of the first other of the pivotally connected plurality of links to create one direction pivotal attachment without back-bending between the links. Further disclosed is a chain system and methods of moving devices with a chain or chain system.

A thrust lifting device that is able to transmit a thrust force for lifting loads, includes at least one articulated lift column provided with at least one meshing part, and with at least one arm directed upward from the meshing part, the lift column made up of links with a link of rank 1 at the upper end of the upwardly directed arm and running links of rank n, where n is between 2 and N, the number of links of the lift column, at least one rotary pinion driving the lift column by the meshing part meshing with the pinion, at least one arm opposite the upwardly directed arm and formed by resting links, the resting links being able to pass to the meshing part and to the upwardly directed arm by rotation of the pinion, and at least one stabilizer that is movable along the upwardly directed arm.