Abstract: Database management system for managing the storage of data and retrieval of stored data, wherein data sets are stored in a table storage means, and wherein data sets which can have a varying number of occupied fields and different declarations for the occupied fields are stored in a common table, and each data set has a definition field which within the common table characterizes the fields valid for the corresponding data set, as well as the field declarations established for the valid fields, wherein particular general information types are allocated to the individual columns of the common table, so that fields of different types of data sets, which jointly relate to a particular general information type, are stored in the same column of the table.

Abstract: A gear motor comprises two meshing gears and a pressure plate pressed against respective lateral surfaces of the gears by pressure in two substantially concentric separate pressure areas arranged on a side of the pressure plate remote from the gears. A control valve controls pressure in one of the pressure areas to adjust a contact pressure of the pressure plate on the gear in such a manner as to increase the contact pressure with an increase in working pressure.

Abstract: A gear pump comprises two gears arranged in engagement with one another, a sealing plate arranged at one side of the gears and insignificantly movable relative to the latter, two pressure fields including a low pressure field and a high pressure field, and forming a narrowing at the side of the high pressure field such that pressure difference at the narrowing act on the sealing plate so as to lift the sealing plate from side surfaces of the gears starting from a predetermined number of revolutions of the gears which is determined by the narrowing.

Abstract: A reversible gear machine which can be used either as a gear pump or as a gear motor regardless of the pressure gradient direction between its inlet and outlet ports includes a housing accommodating meshing gears for rotation about their respective axes which are defined by respective stub shafts extending axially beyond the end faces of the gears. At least one pressure element, which may be constituted by bearing members for the stub shafts, and which is movable axially of the respective stub shafts, has a surface facing away from the gears. A sealing component including a relatively rigid support ring and an elastically yieldable sealing body is accommodated in a groove of the sealing element provided at the aforementioned surface of the latter, such that the support ring contacts the close end wall of the housing and a rib of the sealing body contacts the bottom of the groove and subdivides the latter into two compartments.