Device with an electromotor
An arrangement having an electric motor ( 10 ) has a microcontroller ( 12 ) for influencing at least one motor function and a nonvolatile storage element ( 14 ) for storing at least one variable as a definition for that motor function. The arrangement also has an interface ( 13 a ) for a data line ( 13 ) for transferring the at least one variable, in particular a current limiting value (I ref ) from or to a storage element ( 14 ) by way of the microcontroller ( 12 ), and optionally by way of an internal data bus ( 15 ). The invention also relates to use of the device in the context of batteries of fans, and program-controlled current limitation for startup of an electric motor ( 10 ).
1. An arrangement comprising
an electric motor ( 10 ; 10 ′), and
a microprocessor ( 12 ), for influencing at least one motor function, having a terminal (A, A′), wherein an output level on said terminal (A, A′) of the microprocessor ( 12 ) is switchable by program-controlled switching operations within said microprocessor between a high level and a low level; and
further comprising a first voltage divider ( 20 , 22 ) having two terminals connected, in operation, to two different predefined potentials and having a tapping point ( 18 ) thereof connected to said microprocessor terminal (A, A′) via a resistor ( 17 ), in order to make the potential at that voltage divider tapping point ( 18 ) switchable between at least two values by program-controlled switching of said level on said terminal, and by switching said potential at said tapping point, to influence a parameter of the motor ( 10 ; 10 ′).
2. The arrangement as defined in claim 1 , wherein
the parameter is a current limiting value (Iref) for limiting motor current (i) of the electric motor ( 10 ; 10 ′).
3. The arrangement as defined in claim 1 , wherein said resistor ( 17 ) is of high-resistance configuration.
4. The arrangement as defined in claim 3 , wherein the value of said resistor ( 17 ) is not less than 50 kilohm.
5. The arrangement as defined in claim 1 , wherein
the output at said terminal (A) of the microprocessor ( 12 ) is switchable in program-controlled fashion to a third, high-resistance, state.
6. The arrangement as defined in claim 1 , wherein
said first voltage divider has branches and there is provided, parallel to one branch ( 22 ) of the first voltage divider ( 20 , 22 ),
a second voltage divider ( 160 ) having a tapping point ( 163 ), the potential at the latter tapping point ( 163 ) influencing the parameter of the motor ( 10 ; 10 ′).
7. The arrangement as defined in claim 6 , wherein
the second voltage divider ( 160 ) has a higher resistance as compared to the resistance value of the branch ( 22 ) of the first voltage divider ( 20 , 22 ) to which it is connected in parallel.
8. The arrangement as defined in claim 6 , wherein
the voltage division ratio of the second voltage divider ( 60 ) is designed so that, when the potential at its tapping point ( 163 ) is used as a comparison potential, the result is a low value for that comparison potential.
9. The arrangement as defined in claim 6 , wherein
the potential at the tapping point ( 163 ) of the second voltage divider ( 160 ) defines a current limiting value (Iref) for limiting the motor current (i) of the electric motor ( 10 ; 10 ′).
10. The arrangement as defined in claim 2 , comprising
a nonvolatile memory element ( 14 ) serving to store at least one time value (Ts) after whose expiration a switchover of said output (A) of the microprocessor ( 12 ) is accomplished in program-controlled fashion.
11. An arrangement for carrying out program-controlled adjustment of limitation of current, passing through windings of a motor controlled by an associated microprocessor ( 12 ), wherein
the microprocessor ( 12 ), for program-controlled switchover of a current limiting value (Iref), comprises at least one terminal (A) whose output signal level is switchable, by program-controlled switching operations within said microprocessor, at least between a high and a low signal level and thereby influences the current limiting value (Iref);
further comprising a first voltage divider ( 20 , 22 ) having two terminals connected, in operation, to two different potentials and having a tapping point ( 18 ) thereof connected to said microprocessor terminal (A) via a resistor, the potential at said tapping point serving, in operation, to influence said current limiting value (Iref);
and wherein said output signal level is modifiable in program-controlled fashion during startup of the motor ( 10 ; 10 ′).
12. The arrangement as defined in claim 11 , wherein
the at least one output (A) is switchable to a high-resistance state called the tristate state.
13. The arrangement as defined in claim 11 , wherein
the potential at said tapping point ( 18 ) serves for comparison with a voltage (u) at a measurement resistor ( 36 ) through which the motor current (i) flows;
and wherein the motor current (i) is interrupted when that voltage (u) reaches a predefined ratio with respect to that potential.
14. The arrangement as defined in claim 11 , wherein there is provided, parallel to one branch ( 22 ) of the first voltage divider ( 20 , 22 ), a second voltage divider ( 160 ) having a tapping point ( 163 ), the potential at the latter tapping point ( 163 ) serving for comparison with a voltage (u) at a measurement resistor ( 36 ) through which the motor current (i) flows;
and wherein the motor current (i) is interrupted when that voltage (u) reaches a predefined ratio with respect to that potential at the latter tapping point ( 163 ).
15. The arrangement as defined in claim 14 , further comprising a comparator ( 28 ), serving to make a comparison with a voltage (u) at a measurement resistor ( 36 ) through which the motor current (i) flows.
16. The arrangement as defined in claim 14 , wherein the second voltage divider ( 160 ) has a higher resistance as compared to the branch ( 22 ) of the first voltage divider ( 20 , 22 ) to which it is connected in parallel.
17. The arrangement as defined in claim 14 , wherein
a voltage division ratio of the second voltage divider ( 60 ) is so chosen that, when the potential at its tapping point ( 163 ) is used as a comparison potential, the result is a low value for that comparison potential.
18. The arrangement as defined in claim 15 , wherein
the voltage (u) at the measurement resistor ( 36 ) is filtered by a low-pass filter ( 38 , 42 ) before comparison with the aforesaid comparison potential.
19. The arrangement as defined in claim 18 , wherein
the low-pass filter is configured as a first-order low-pass filter ( 38 , 42 ).
20. The arrangement according to claim 1 , further comprising a data line ( 13 ) for connection to a data source, and wherein
the microprocessor ( 12 ) comprises a predefined memory element ( 332 ) for storing an address conveyed via the data line ( 13 ), an arrangement ( 14 , 330 ) for storing an address ( 324 ) of the arrangement to be addressed, and a comparator for comparing those two addresses.
21. The arrangement according to claim 1 , further comprising a directory ( 280 ) for storing an object to be transferred via a data line, said obiect having at least one characteristic, and further having a memory element ( 332 ), for storing a variable characterizing said object said memory element being associated with the microprocessor ( 12 ) so that
by using that variable, at least one characteristic ( 286 , 288 , 290 ) of that object can be retrieved, for processing thereof, from said directory ( 280 ).
22. The arrangement as defined in claim 21 , wherein the characteristic is the length ( 286 ) of that object.
23. The arrangement as defined in claim 21 , wherein the characteristic is the hardware address ( 288 , 290 ) of that object.
24. The arrangement as defined in claim 9 , comprising
a nonvolatile memory element ( 14 ) serving to store at least one time value (Ts) after whose expiration a switchover of the output level at said output (A) of the microprocessor ( 12 ) is accomplished in program-controlled fashion.