DEVICE FOR ISOLATED FAN CONTROL AND FAN SYSTEM AND CONTROL METHOD

Abstract

The present disclosure relates to a fan motor control device comprising a control signal input for applying a rotational speed control voltage as the control signal input signal and a control signal output for picking off a control signal output signal for connecting to a fan motor, where modulation means are connected downstream from the control signal input, said modulation means being designed to convert the control signal input signal into a digital and/or pulsed modulation input signal, and isolated transmission means are connected downstream therefrom, which transfer the digital and/or pulsed modulation input signal into a digital and/or pulsed modulation output signal isolated from the control signal input, which is converted into the control signal output signal that can be picked off on the control signal output by means of demodulation means connected downstream from the transmission means.

Claims

1. A fan motor control device, comprising a control signal input for applying a rotational speed control voltage as the control signal input signal and a control signal output for tapping a control signal output signal for connection to a fan motor, wherein connected downstream from the control signal input are modulation means, which are designed for converting the control signal input signal into a digital and/or pulsed modulation input signal and which are upstream from isolating transmission means that transmit the digital and/or pulsed modulation input signal to a digital and/or pulsed modulation output signal isolated from the control signal input, said modulation output signal being converted by demodulation means downstream from the transmission means into the control signal output signal tappable at the control signal output.

2. The device according to claim 1, wherein the control signal input is designed so that the variable rotational speed control voltage can be applied to this signal input with a minimum voltage, including a predetermined voltage interval from the 0V level, wherein a range of the rotational speed control voltage between preferably 3.3V and 20V, especially preferably between 5V and 15V, most especially preferably between 5V and 10V, can be applied.

3. The device according to claim 1, wherein operating voltage power supply means are connected downstream from the control signal input and form a power supply voltage for electronic system(s) provided for the transmission means at the input end from a predetermined dc voltage component of the applied control signal input signal.

4. The device according to claim 1, wherein the control signal output is designed with two poles for connection to the fan motor.

5. The device according to claim 1, wherein the fan motor is designed as a dc motor, preferably single-phase or three-phase, especially brushless.

6. The device according to claim 1, wherein the modulation means are implemented without programmed or programmable logic means and are designed with a control amplifier and/or an operational amplifier wired for digitization of the rotational speed control voltage.

7. The device according to claim 6, wherein the modulation means have a Schmitt trigger, which is designed on the basis of an operational amplifier and compares a periodic, and in particular sawtooth, internal auxiliary signal with the analog control signal input signal, wherein the internal auxiliary signal is preferably generated by means of another operational amplifier.

8. The device according to claim 1, wherein the isolating transmission means have an optocoupler and/or an inductive isolator, in particular implemented by a preferably standardized integrated circuit and/or a capacitive isolator.

9. The device according to claim 1, wherein the demodulation means have an analog low-pass circuit, preferably constructed from discrete components, in particular by connecting a resistor to a capacitor.

10. The device according to claim 1, wherein the transmission means are implemented in two channels so that a second channel is arranged for isolated feedback of a fan motor-specific signal of the connected fan motor, in particular utilizing a second optocoupler of a joint optocoupler housing of the transmission means, preferably for tapping at an additional signal connection on the input end.

11. A fan system, comprising a fan motor control device according to claim 1, wherein as well as a fan motor electronic system controlled by the control signal output and driving the stator windings of a fan motor.

12. The fan system according to claim 11, wherein the fan motor control device and the fan motor electronic system are arranged on a circuit board and/or are arranged in a shared fan housing.

13. The fan system according to claim 11, wherein a side dimension of the fan housing is in the range between 110 mm and 130 mm, in particular between 115 mm and 125 mm, and/or the maximum power consumption by the fan motor electronic system is 15 W, more preferably 10 W, and even more preferably 5 W.

14. A method for controlling a fan motor, in particular a method for operating a fan motor control device according to claim 1 comprising the following steps: Applying a variable rotational speed control voltage having a dc voltage component at the control signal input Generating a pulsed and/or digital modulation input signal from the rotational speed control voltage at the input end by means of modulation means provided, Transmitting the modulation input signal by means of isolating transmission means into a digital and/or pulsed modulation output signal isolated from the control signal input; and Converting the digital and/or pulsed modulation output signal by the demodulation means provided into a control signal output signal that can be tapped at the control signal output for the fan motor.

15. The method according to claim 14, wherein the control signal output signal is applied to a fan motor electronic system, which energizes the stator windings of the fan motor, preferably designed as a single-phase or three-phase dc motor, in particular brushless.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Additional advantages, features and details of the present disclosure are derived from the following description of preferred embodiments and on the basis of the drawings,

[0031] in which

[0032] FIG. 1 shows a block diagram of a first embodiment of the fan motor control device according to the present disclosure with a downstream fan motor electronic system of a fan motor, and

[0033] FIG. 2 shows an embodiment of the modulation means implemented by the circuitry of electronic components comprising an operational amplifier.

[0034] FIG. 1 shows a schematic block of a first embodiment of the fan motor control device 1, in which transmission means 9 according to the present disclosure are arranged on the input end and on the output end, subdividing the fan motor control device 1 according to the present disclosure into electronic systems. At the input end, the fan motor control device 1 receives a rotational speed control voltage, which is carried at the output end to signal output 13 via the control signal input 6, in particular a dual-pole control signal output for connection to a fan motor electronic system 2, which energizes the starter windings of a fan motor 3.

DETAILED DESCRIPTION

[0035] The transmission means 9 generate an isolated digital and/or pulsed modulation output signal 11 from a supplied digital (i.e., a signal digitized via means 7 described below) and/or pulsed modulation input signal 10. In the embodiment illustrated here, this is accomplished by an optocoupler that converts the modulation input signal 10 by light pulses into modulation output signal 11, which is detected by detector means. In addition, a second channel is provided for the transmission means 9, permitting output of a measurement signal, based on the input side, in particular a tachometer signal of the fan motor electronic system 1.

[0036] Operating voltage supply means 8, supplying power to the electronic system arranged at the input end, are provided for the input end. It is advantageous in particular that the operating voltage supply means 8 are supplied with power from a dc voltage component contained in the rotational speed control voltage and form the power supply voltage from this, in particular a dc power supply voltage, with which it is possible not only to advantageously reduce the number of contacts provided at the input end, but also to reduce the complexity and cost of the wiring in assembly of the fan motor control device in addition to achieving lower manufacturing costs.

[0037] At the input end, the electronic system is formed by the modulation means 7 as well as proportionally by the transmission means 9 and is thus supplied with power by the operating voltage supply means 8.

[0038] The modulation means 7 generate the pulsed and/or digital modulation input signal 10 from the rotational speed control voltage applied at the input end. A preferred embodiment of the modulation means 7 is described in greater detail below in conjunction with FIG. 2.

[0039] At the output end, the electronic system is formed by the demodulation means 12 and proportionally by the transmission means 9 and supplied with a power supply voltage via power supply unit 4.

[0040] The demodulation means 12 convert the digital and/or pulsed modulation output signals 11 into a control signal output signal that can be tapped at the output of the fan motor control device 1 for connection to a fan motor electronic system 2. In a preferred embodiment, the demodulation means 12 are embodied in the form of a low-pass filter, which is especially preferably embodied by the advantageous circuitry of discrete components, most especially preferably in the form of a resistor and capacitor network.

[0041] The rotational speed control voltage is supplied to a fan motor electronic system 2 consisting of electronic components, comprising power electronics and energizing the stator windings of a dc fan motor 3, designed as a dc motor, preferably a single phase or three-phase dc motor, preferably brushless. The fan motor electronic system 2 is supplied with power via the power supply unit 4 connected to an ac current system (not shown); the power supply unit generates a dc voltage from the line voltage in a known manner. The dc voltage is converted by another dc voltage converter 5 into another dc voltage, in particular a voltage of a different value, supplying power to the electronic system of the fan motor control device 1 situated on the output end, in addition to supplying power to logic units and components of the fan motor electronic system 2.

[0042] An embodiment, in which the fan motor control device 1 according to the present disclosure and the fan motor electronic system 2 are both arranged on a circuit board, is particularly preferred. It is additionally preferred that the circuit board is arranged in a housing having side lengths between 115 mm and 125 mm, which is also associated with the fan motor 3, together forming a module. This standardization (the dimension of the circuit board is one example) ensures a broad field of use for the device as well as the system according to the present disclosure because it can replace established and widely used systems having an identical module size.

[0043] Variants of the fan motor control device according to the present disclosure are also possible, in which the demodulation means 12 deliver a digital control signal output signal, which is processed further in the fan motor electronic system 2 for controlling the fan motor 3.

[0044] FIG. 2 shows an embodiment of the modulation means 7, in which electronic components, comprising operational amplifiers 20, are combined in an otherwise known type of Schmitt trigger. The circuit compares the rotational speed control voltage applied at the control signal input 6 with an internal auxiliary signal. This auxiliary signal is a sawtooth voltage signal having a fundamental frequency of 500 Hz, for example, generated here by means of another operational amplifier having of an arrangement of electronic components as an example. In the present case, the arrangement is given as an example and is preferably designed as a sawtooth generator 22 having an integrated operational amplifier. In a particularly preferred embodiment, the two operational amplifiers are combined for generating the auxiliary signal and for the design of the Schmitt trigger in a shared component housing, which advantageously supports the compact design of the fan motor control device 1 and permits inexpensive acquisition of components. The Schmitt trigger forms the modulation output signal, in that it outputs a level varying between logic one and logic zero at the output end with a correspondence in the voltage signal levels applied at the input, thus resulting in digitization of the analog signal applied at the input.

LIST OF REFERENCE NUMERALS

[0045] 1 fan motor control device [0046] 2 fan motor electronic system [0047] 3 fan motor [0048] 4 power supply unit [0049] 5 dc voltage converter [0050] 6 control signal input [0051] 7 modulation means [0052] 8 operating voltage supply means [0053] 9 transmission means [0054] 10 digital and/or pulsed modulation input signal [0055] 11 digital and/or pulsed modulation output signal [0056] 12 demodulation means [0057] 13 control signal output - [0058] 20 operational amplifier [0059] 21 Schmitt trigger [0060] 22 sawtooth generator