Daimler Ag

Daimler Chrysler Ag

Jan Gaertner

Thomas Koch

Juergen Wertenbach

Roland Caesar

Juergen Schrader

Wolfgang Straub

Thomas Meier

Andreas Zygan

Andreas Franke

Thomas Finkenberger

Dominik Mall

A method and a device for operating a waste heat utilization device for an internal combustion engine of a motor vehicle is disclosed. The waste heat utilization device contains a waste heat utilization circuit in which a working medium circulates. A conveyor, an evaporator, an expansion machine, and a condenser are disposed in the waste heat utilization circuit. A basic adjustment of the waste heat utilization circuit is provided, which as a function of a heat input into the working medium adjusts the mass flow rate at the conveyor and/or the ratio between high pressure and low pressure at the expansion machine. In addition, a pilot control is provided which recognizes a change of the operating point of the internal combustion engine and, when the operating point is changed, controls the condensation output of the condenser in accordance with a mass distribution of the working medium in the waste heat utilization circuit optimized to the new operating point.

Method for operating a waste heat utilization device

In a waste heat utilization arrangement for an internal combustion engine of a motor vehicle including a waste heat utilization circuit in which a working medium is circulated, a pumping device for pressurizing the working medium, an evaporator for vaporizing the working medium by waste heat of the internal combustion engine, an expansion machine for expanding the working medium while extracting mechanical energy therefrom and a condenser for condensing the working medium in a resting state, the waste heat utilization circuit is in communication with a pressure store capable of maintaining a pressure for setting and ensuring a predetermined adjustable minimum pressure of the working medium in the waste heat utilization circuit.

Waste heat utilization device and operating method

A convertible motor vehicle with at least two vehicle seating rows and with at least two side doors is provided. A respectively associated door column is arranged in between the doors, and an active rollover protection system is provided in the region thereof. The door columns end upwards in the region of an associated waistline of the motor vehicle, and the rollover protection system is at least substantially arranged below the waistline of the motor vehicle in a retracted position.

Convertible motor vehicle with active rollover protection

A method for air conditioning a motor vehicle, in which, in a heating mode, the passenger compartment of the motor vehicle is heated via a passenger compartment heat exchanger () through heat pump operation of a refrigerating circuit (). To prevent fogging of the windows of the motor vehicle from the outset, the temperature and humidity in the passenger compartment are recorded by measurement technology, and when the temperature is in a predefined range and the atmospheric humidity reaches a defined threshold, the mass flow of refrigerant in the circuit is throttled upstream of the passenger compartment heat exchanger (), in such a manner that the moisture contained in the air stream passing the passenger compartment heat exchanger () is at least substantially condensed at the passenger compartment heat exchanger (), and the moisture which has already condensed at the heat exchanger () remains at the heat exchanger (). The passenger compartment is heated by a heat source which is outside the circuit () until the temperature in the passenger compartment exceeds an upper limit temperature of the predefined range.

Method for air conditioning a motor vehicle

A refrigerant circuit for a motor vehicle air-conditioning system has a refrigerant compressor, a cooler connected downstream of the refrigerant compressor, a restrictor for expanding the refrigerant, and an evaporator for transferring heat to the refrigerant. Pressure in the refrigerant circuit is measured firstly on the high-pressure side and secondly on the low-pressure side. An air-conditioning system can be driven directly or indirectly by the motor vehicle driving engine. The refrigerant in the refrigerant circuit is almost completely liquefied upstream of the restrictor, so that it is easy to determine the refrigerant mass flow. As a result, it becomes possible to determine the compressor torque which is consumed by the refrigerant circuit and to control the motor vehicle driving engine accordingly.

Growing community of inventors

Leonberg, Germany

Jan Gaertner