Data processing: vehicles – navigation – and relative location – Vehicle control – guidance – operation – or indication – Vehicle diagnosis or maintenance indication
Reexamination Certificate
1997-09-23
2001-10-23
Louis-Jacques, Jacques H. (Department: 3661)
Data processing: vehicles, navigation, and relative location
Vehicle control, guidance, operation, or indication
Vehicle diagnosis or maintenance indication
C701S029000, C701S033000
Reexamination Certificate
active
06308121
ABSTRACT:
BACKGROUND OF THE INVENTION
Field of the Invention
The invention relates to an electronic control unit, in particular for a device provided in a motor vehicle, including a computer, a first data memory and a second data memory connected to a temperature sensor, wherein data are transmitted from the first to the second data memory.
Such a control unit is disclosed in U.S. Pat. No. 4,181,944, for example.
Modern electronic control units are increasingly being fitted to actuators to be controlled or integrated in them. In the field of motor vehicle technology, the following may be mentioned as examples of such control units: Transmission controllers integrated in transmissions (so-called Prodmod transmission controllers), integrated hydraulic and electronic systems and engine controllers installed in internal combustion engines.
As a result of attaching the control units to the mechanical and hydraulic devices in that way, the electronic circuits are subjected to increased stresses, in particular to higher temperatures, due to their environment. Thus, for example, temperatures of up to 140° C. or more may occur in automatic transmissions. The meaning thereof is that the electronic components have to be operated right up to the limits of their technical specifications.
Those components that are stressed to a greater extent include, in particular, electrical program and data memories, to which type-specific data and adaptive values of the control unit (for example learning values for wear compensation) are written and which must ensure protected management of such data. Examples of such memory modules are EEPROM and flash modules. Their task is to store variable data (for example learning values, diagnostic information, fault memory contents or calibration values) even when the control unit is disconnected from its supply voltage.
SUMMARY OF THE INVENTION
It is accordingly an object of the invention to provide an electronic control unit, in particular for a device provided in a motor vehicle, which overcomes the hereinafore-mentioned disadvantages of the heretofore-known devices of this general type and which still operates reliably under relatively high ambient loading, especially at higher temperatures. In particular, electrically erasable memory modules contained in the control units are intended to reliably store data written to them.
With the foregoing and other objects in view there is provided, in accordance with the invention, an electronic control unit, in particular for a device provided in a motor vehicle, comprising a first volatile data memory; a second nonvolatile data memory for receiving and storing variable data from the volatile data memory; a temperature sensor supplying information signaling a temperature of the nonvolatile data memory; and a computer receiving the temperature information from the temperature sensor, the computer copying data from the volatile data memory to the nonvolatile data memory only when the temperature signaled by the temperature sensor falls below a predetermined value, and data being read from the nonvolatile data memory up to an upper temperature limit lying above the predetermined value.
In accordance with another feature of the invention, the data are copied cyclically from the volatile data memory to the data memory during normal operation of the control unit.
In accordance with a further feature of the invention, there is provided a switch to be opened by a user of the electronic control unit for enabling the computer to copy data from the volatile data memory to the nonvolatile data memory.
In accordance with an added feature of the invention, there is provided a supply voltage source, the volatile data memory having an operating voltage input connected to the supply voltage source, and a switch opened by the computer after copying has taken place or if a signal of the temperature sensor has exceeded the predetermined value.
In accordance with an additional feature of the invention, the switch is subsequently closed for suppressing copying of values back from the nonvolatile data memory to the volatile data memory.
In accordance with yet another feature of the invention, the predetermined value corresponds to a maximum permissible erasure and writing temperature for the nonvolatile data memory.
In accordance with a concomitant feature of the invention, there is provided an internal operating voltage supply; an operating voltage input of the volatile data memory connected to the operating voltage supply; a supply voltage source for the computer and if appropriate for the volatile data memory and the nonvolatile data memory; and a switch connected to the computer and to the supply voltage source for internally disconnecting the supply voltage source with a command from the computer and if appropriate internally disconnecting the supply voltage source from the volatile data memory and the nonvolatile data memory with a command from the computer; the computer opening the switch after the temperature signaled by the temperature sensor has fallen below the predetermined value and after the data have been copied from the volatile data memory to the nonvolatile data memory.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in an electronic control unit, in particular for a device provided in a motor vehicle, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
REFERENCES:
patent: 4181944 (1980-01-01), Yamauchi et al.
patent: 5276619 (1994-01-01), Chara et al.
patent: 5379219 (1995-01-01), Ishibashi
patent: 5428542 (1995-06-01), Liesveld
patent: 5500797 (1996-03-01), Noger
patent: 5581462 (1996-12-01), Rogers
patent: 5687149 (1997-11-01), Meunier
patent: 0 635 785 A1 (1995-01-01), None
Greenberg Laurence A.
Lerner Herbert L.
Louis-Jacques Jacques H.
Siemens Aktiengesellschaft
Stemer Werner H.
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