摘要:
A device for setting the speed of, in particular, an excavator engine which is to operate at a speed adapted to the type of work to be done and is automatically shifted to resting speed when no work is done. In this manner, fuel consumption and the disturbing effect of unnecessarily high noise levels are reduced. The setting device includes simple electronic control units and actuates the fuel-controlling lever of the engine fuel injection unit. A d.c. servo motor is connected to said fuel-controlling level and is supplied with a reference value signal corresponding to the desired engine speed. By manual activation of a push-button on the control lever, the device provides the possibility of manually stepping the engine working speed upwards or downwards to at least three different levels. The device also includes a resting speed unit ("idling unit") having a preset high and preset low resting speed. If the manual control means of the machine are not activated for a given short period of time, the unit provides a high resting speed, and if no manual control means is activated for a further period of time, it provides a low resting speed. On activation of any manual control means, the engine resumes the actual working speed.
摘要:
The invention relates to a method and a device for reducing the piston speed in a piston and cylinder assembly (1), as the piston approaches the end position. The piston end position is sensed, and a signal is generated for starting the end position dampening. Dampening is effected in two steps. In the first step (14), a time delay is provided and in the next step (15), the actual braking (retardation) of the piston is effected.The invention also comprises an electronic braking device comprising a dampening activation unit (13) which is connected to transducers (6), a braking delay unit (14) connected to the unit (13) and also to the control lever (5) at issue and a reference signal source, as well as a braking unit (15) connected to the delay unit (14) and adapted, upon activation, to provide a signal (U) to a setting system (3) for controlling the supply of pressure fluid to the piston and cylinder assembly (1).