O&k Orenstein & Koppel Aktiengesellschaft

Horst Kohlmorgen

Ulrich Kr&uuml;ger

Hans-Joachim Waegner

A method and apparatus for braking a revolvable superstructure of a working machine by counter-steering. A working machine has a superstructure which is driven by a motor via a transmission. A control lever operates a control valve which sends signals to a pivoting pump. The control lever has at least one neutral position and at least two switching positions. When the control lever is moved to a braking position, a switching logic circuit coupled to the pivoting pump is actuated and reverses the pivoting pump. This reverses the direction of revolution of the superstructure and brakes the revolution of the superstructure by counter-steering. A monitoring device coupled to the switching logic circuit monitors the number of revolutions of the superstructure. The braking is stopped when the monitoring device detects that the superstructure has come to a standstill.

Method for braking a revolvable superstructure of a working machine and a pivoted brake unit

A method for the power-shiftable change-over of a hydrostatic vehicle drive of a mobile construction machine, comprising at least one hydrostatic capacity pump, a hydrostatic drive motor and a two-stage power-shift transmission, which drives the axle(s) of the construction machine via its drive shaft, wherein the power-shift transmission is shifted with a change-over valve, which method is to be modified such that an operationally safe automatic change-over in dependence on the load is possible between the shifting stages of the power-shift transmission. This object is achieved by activating a switch ( ), which causes at least two pressure switches ( ) that are operatively connected to at least one switching element ( ) to be successively activated with different hydraulic contact pressures for the load-dependent automatic change-over of the power-shiftable transmission ( ), wherein the switching element ( ) is activated by one or the other pressure switch ( ) in dependence on preset load conditions in the hydraulic circuit and this switching element then electrically actuates the change-over valve ( ) in order to effect the change-over of the power-shift transmission ( ).

Growing community of inventors

Dortmund, Germany

Horst Kohlmorgen