HYDRAULIC ELEVATOR, COMPRISING A PRESSURE ACCUMULATOR WHICH ACTS AS A COUNTERWEIGHT AND A METHOD FOR CONTROLLING AND REGULATING AN ELEVATOR OF THIS TYPE

摘要

The invention relates to a hydraulic elevator, comprising a pressure accumulator (17) which acts as a counterweight. In said elevator, hydraulic oil which can be supplied to or taken from a tank (14) can be conveyed using a first pump (12) through a pump line (11), at least one valve unit (7) and a cylinder line (6), to or from a hydraulic drive (2) for an elevator compartment (1) and can be conveyed using a second pump (15) via a solenoid valve (18) from or to the pressure accumulator (17). The two pumps (12, 15) are rigidly interconnected and can be driven by an electric motor (13). According to the invention, a single valve unit (7) is located between the first pump (12) and the hydraulic drive (2) which consists of a pilotable valve (8) and a first non-return valve, connected in parallel thereto (9). The rotational speed of the electric motor (13) can be regulated. A control and regulating unit (20) is also provided which acts upon a power regulator (21) for the electric motor (13), the solenoid valve (18) and in addition, the pilotable valve (8) during descent, in order to control and regulate the speed of the compartment (1). The invention relates to a hydraulic elevator of this type and to a method for controlling and regulating the same. The invention reduces the demand on the electric energy required to drive the motor (13) and thus to drive the hydraulic elevator.