A large rectangular floor mat having an integral cover providing a substantially smooth, unbroken top surface is constructed in the form of individual sections permanently connected together only by an overall top sheet constituting a part of the cover and arranged so that the entire mat can be readily "roll-folded" inwardly from its two ends to form a long narrow stack of mat sections on the floor which can then be moved away to one side, all without requiring any disassembly of the mat. A sepa...

In a bicycle a free wheel comprises a plurality of sprocket wheels each provided with gear teeth having a different dent on teeth number into which the driving chain can be selectively geared. The free wheel includes a discoidal protective means mounted outside the minimum dent-numbered one of these sprocket wheels at the same interval as that at which the sprockets are mounted for preventing the driving chain from moving outwardly when it is engaged into any selected sprocket wheel.

A power and free conveyor has trolleys driven along a fixed track by abutments on the trolleys being engaged by dogs depending from an endless drive chain. At a station, a stop is spring-biassed into an operative position in which it depresses the abutment of a trolley out of the path of the dogs. A bellcrank lever has one arm which can be moved into that path. When a dog turns the one arm, the other arm retracts the stop, and the dog then moves the trolley from the station. Thereupon, the troll...

Press-free polyester-cotton fabrics of improved durability are obtained by applying a textile resin only to the yarns that travel in one direction in the textile fabric, e.g., either the warp yarn or the filling yarn.

A free rotor vibrator of the class including a case with an internal cylinder race within which a rotor of less diameter orbits in bearing contact therewith so as to exert a radial centrifugal force which is useful in fields such as the placement of concrete. The invention includes valving means for sequentially connecting force means such as plungers to sources of fluid under alternately elevated and reduced pressure so as to cause the rotor to orbit in the case. The valving means comprises a r...

A reaction mixture composed of an acrylonitrile polymer, a water-soluble alkylenepolyamine and a water-soluble alcohol on heating yields a solution of a poly-2-vinylimidazoline in the alcohol. The alcohol separates, usually as a supernatant layer, when the solution is acidified with an aqueous solution of a strong acid.

A free standing foldable cart having a rectangular base shelf with a post in each of the four corners and a pair of longitudinally spaced end frames. The posts of each end frame are pivotally connected to a corresponding post of the base shelf for rotation of each end frame about a single axis of rotation to fold the end frames about the base shelf. In the folded position, two or more carts may be vertically stacked upon and moved about the running gear of the bottom cart.

A multiple free wheel for a bicycle comprising a low speed sprocket wheel and a high speed sprocket wheel, wherein the dents of the low speed sprocket wheel are so formed as to engage with a driving chain at the interval equal to one pitch thereof so that when the driving chain is geared into the high speed sprocket wheel it is not disengaged from the low speed sprocket wheel however big the difference may be in dent number between the two sprocket wheels.

A tandem free-piston machine has two movable trains comprising drive and compressor pistons. Synchronizing means are provided between these trains and include an elastic member to absorb at least partly any momentary difference in the forces to which the movable trains are subjected. The synchronizing means may be rack and pinion, or lever and connecting rod means. The elastic member may be a torsionally elastic shaft connecting two pinions, or a bendable elastic bar constituting one of said lev...

A power-and-free conveyor system of the type having work carriers each consisting of coupled front and rear trolleys adapted to be propelled along a track by lugs on an overhead chain drive and each adapted further to be disconnected from the drive in a localized close pack section of the conveyor by a cam plate on the rear trolley of the preceding carrier, and wherein the drive and the cam plate of each carrier have novel means which are uniquely cooperative to prevent the carrier from back-sli...