Abstract: The invention relates to a device for correcting the levels at which book blocks, emerging from a rounding and backing machine, are transferred to a machine downline, the level corrections being referred to a level predetermined by the latter machine, this level correction device possessing a pair of correcting grippers that grip the book block by means of jaws which can be caused to swing by being driven from a cam mechanism via link motion and lever assemblies that enable the throw of the jaw-swinging movement to be varied by adjusting the slidable link of the link motion within its slot guide.

Abstract: An apparatus for the adsorptive cleaning of gases comprises a rigid hermetically sealed housing provided internally with an inner vessel connected with the outer housing by a fluid carrying duct which is yieldable along the axis of the inner housing. The inner housing rests upon a grate and can be surrounded by a layer of thermal insulation. A filling of the adsorbent is provided in the inner vessel which is free from the usual bottoms carrying beds of adsorbent.

Abstract: Plates of a plate heat exchanger, defining between them a space adapted to be traversed by a heat-exchange fluid, are held together and are soldered in a chamber in which the plates are heated by passing a heating fluid, generally an inert gas, directly through the passages between the plates.

Abstract: Plates of a plate heat exchanger, defining between them a space adapted to be traversed by a heat-exchange fluid, are held together and are soldered in a chamber in which the plates are heated by passing a heating fluid, generally an inert gas, through the passages between the plates. The apparatus comprises means for heating and cooling the fluid and a temperature-monitoring device connected to the heating means for controlling the latter. Preferably the heating fluid circulation path includes a drying station.

Abstract: For the production of high pressure O.sub.

Abstract: A double-flow regenerator has several separate groups of tubes each of which is used for a respective fluid heat-exchange medium. These tubes are all received in a packed housing through which fluids to be treated are passed in heat-exchange relationship with the packing in the housing through the tubes in contact with this packing. Each group of tubes terminates within the housing at each end of a plurality of separate manifold connectors. Thus the middle of the housing is provided with a plurality of manifolds for the inner end of each tubing group and the outer end is provided with a plurality of such manifolds for each group, with several such manifold connectors provided for each group for minimum variation in tube lengths within the group.