DD214205A1 - TORQUE MEASUREMENT WITH ELECTRONIC SIGNALING FOR DISPLAY - Google Patents

Abstract

The invention relates to a torque measurement with electronic signal acquisition for the display, without burdening the electrical machine by the measuring process and is particularly advantageous for torque measurement of small and small electrical machines low speed. The aim of the invention is the detection of torque fluctuations or the total torque. The object of the invention is that the torque-dependent display signal is obtained exactly proportional to the torque to be measured with minimum component expenditure. The electrical Wicklungsstranggroessen are analog or digital monolitisch integrated, hybrid or discretely constructed circuits fed to a multiplier whose Ausgangsgroesse is passed to an adder, can abut the one, several or all Wicklungsstraenge whose measurement structure is equal to the first phase winding. With digital measuring methods, the multiplication and addition devices can be taken over by an electronic computer.

Description

a) Title of the invention

Torque nosine with electronic signal acquisition for display

b) Field of application of the invention

The invention relates to the measurement and detection

of torques and torque fluctuations of electrical machines, in particular of small and micro machines low speed ι load without the electric machine by the measuring process au. It is preferably applicable to Gleich

electric motors with mechanical or electronic commutation devices, synchronous motors with permanent magnets and electric machines for the immediate transmission or reception of the. Angular displacement of rotating parts, e.g. B. resolvers, Selsyn (synchronous systems) and linear motors *

c) Characteristic of the known technical solutions

It is described a variety of measurement methods in the Pachlitöratur with which torques can be measured, however, which are applicable only to larger or large electric machines and the measuring method, eg. B # Pronysche bridle, eddy current brake or pendulum machine, not the dynamisehe behavior of torque curves at the

allow measuring wave. The same applies to the

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phm's torque measurement, in which the increase in resistance occurring due to the torsion of the shaft is evaluated and the inductive torque transmitters based on the differential power principle ·

Magneto-elastic or capacitive torque gauges are also unsuitable, as they are ultimately based on the evaluation of the torsion on the shaft to be measured »As with small and very small machines, the shaft

oversized, hardly measurable torsions are given ·

It is also known that DC commutator motors have a linear relationship between torque and motor current. The upstream

However, taking measure for torque measurement is only suitable for determining the average torque, since the conditional by the inertia of the engine mass limit frequency of the mechanical system is very low. "In addition, that the

Current decrease of the motor periodically fluctuates during a revolution of the rotor due to the commutation, so that the evaluation of the dynamic curve of the torque to be measured is difficult ·

From DE-OS 2 414 336 it is known to detect the irregularity of the rotational speed of the rotor by attaching small magnets on the rotor and fixed halves, and to convey them to a device for display.

Further devices for detecting the torque are disclosed in DD-WP 135 672, DE-OS 3 013 or DE-OS 2 702 981, in which

Hall elements or other position indicator elements and additional electronic devices also lead to a display device.

It is also known, with the help of the induced winding strand tension and the winding strand flow

receive an output signal via analogue amplifiers indicating the mean as well as the instantaneous torque.

The disadvantage is that once in the individual measurement methods, the measurement accuracy high requirements

; ments does not correspond, the measuring methods are not

or difficult to combine, for. B. for analog and / or digital display, or a high equipment cost is required *

d) Object of the invention

The object of the invention is to find a circuit arrangement which also in its basic version displays an analog and / or digital measurement of the average torque and / or the torque fluctuations under "

Elimination of identified disadvantages of known circuits and no load on the motor to be measured.

e) Presentation of the essence of the invention

The invention is based on the technical object

To find a torque measuring, the interference of technological tolerances

of the field profile in permanent magnets or the magnetic poles as well as the commutation detected and loaded by the measurement of the engine ·

According to the invention, the object is achieved in that »that the voltage drop of a winding strand

and the associated winding phase current amplifier means are fed, the output variables of which is proportional to the voltage induced in the winding and the winding phase current.

These outputs are at the input of a multi

plotting device whose output is the product of the amplifier devices * The output of the multiplier device is supplied to an adder whose input is connected to one, several or all winding phases

same device structure of the measuring device as a winding strand ·

The output signal of this device for adding the product size of the individual winding strands is proportional to the instantaneous value of the torque

a winding strand, several or all winding strands, The devices for multiplication and for adding the measured values are analog or digitally operating assemblies,

In digital mode, the operations become

the multiplication facilities and the addition

^ device for the winding phase values of one

electronic computer taken at the output directly from a digital measurement can be removed or by means of a digital-to-analog converter

an analogue measured value (signal) is obtained «

The output of the electronic computer is simultaneously connected via control lines to the means for the voltage and current detection of the winding or the winding * Advantageous are used as amplifiers for the voltage and current values as well as for multiplication and addition in analog operation monolithically integrated circuits such as operational amplifiers and quadrature multiplier ,

f) embodiment

The invention will be explained in more detail below using an exemplary embodiment.

In the accompanying drawing show

Pig, 1 is a Signalflußbild the arrangement according to the invention in an analogous operation

KLG. 2 shows a signal flow diagram of the arrangement according to the invention for a motor with two phase windings in digital mode of operation.

After Pig. 1 is connected to terminal 1, which is connected to the input of a device 3 for detecting the induced voltage, the voltage u. the first Wibklungsstranges a DC motor, from which by means of the device 3, a signal is formed, which is proportional to the induced voltage

is at the exit of the device 3 »the terminal 5, is available»

The current i. range is detected via terminal 2, supplied to the input of a device 4 for detecting the phase current of the winding, and converted by the latter into a 3-phase proportional signal which is present at the output of the device 4,

the terminal 6 is provided. The terminals 5 and β are connected to the inputs of the means 7 for multiplying the output signals of the means 3 and 4. The output signal m of the means 7 is proportional to the product of

Input signals, d, h. proportional to the proportion of the moment of the first phase winding in the total torque and can be taken from the output terminal 8 · The terminals 11,. "k are connected to the outputs of the other phase windings

connected devices and their linkage, so that the signals m _2. , "m are applied to them, which 'are proportional to the torque components of the development strands 2 ·· _# except with the outputs of the individual winding

strands 1 ··· _η , the terminals 11 .., ^ connected to the inputs of the device 9 for adding the individual moments.

At the output terminal 10 of the device 9 is thus a signal proportional to the sum of the

Input signals of the device 9 and thus proportional to the total torque m of the engine,

ges

Pig, 2 shows the signal flow diagram for a DC motor with two winding phases in digital mode ·

The strand voltages u. and U ₂ are the input terminals 1 and 21 of the devices 3 and 23 for

O O β

Detecting the winding phase voltages supplied and converted by means of these devices into digital signals.

The winding phase currents i. and ip become the input terminals 2 and 22 of the devices 4 and 24

supplied to the detection of the winding phase current and also converted by means of these devices into digital signals. The outputs of the devices 3 »4, 23 and 24 are via cable bundles

•} Q 25, 26, 27 and 28 with the inputs of a rake

unit 29, z · B · a microcomputer, connected. In this device 29, the digital values of the winding phase voltage and the current are multiplied together for each line and the products are optionally added together

thus corresponds to the torque of one, several or all winding strands.

The digital value of the torque is available at the trunk group 30 for further processing or display *

A further processing can take place via the device 31, whose inputs are connected to the outputs of the device 29 and converts their digital output signal into an analog signal, which is also proportional to ge after switching a,

several or all of the winding strands and can be removed at the output terminal 32 · via the control lines 33 and 34 »connect the devices 3 and 4 or 23 and 24 with the device 29, it is possible, the facilities

3, 4, 23 and 24 from the device 29 to control.

Claims (4)

Erfinaungaanspruch "U torque measurement with electronic signal acquisition for the display of the torque of one, several or all winding phases as well as the torque ens ch fluctuations, characterized that the voltage drop (u 1) of a winding strand as well as its current (I ₁ ) are fed via the terminals (1) or (2) to a device (3) or (4) whose output is proportional to IQ tional of induced in the winding strand Span and the winding phase current (i ^) and via the terminals (5) and (6), respectively, to a device (7) whose output (m ..) is the product of the output variables of the devices (3) and (4) and the output (m.) over the Terminal 8 is fed to a device (9) which is an addition device and, in the case of multi-strand measurement, adds the individual input variables (m, m) to m) and at the output terminal (10) the sum 0 a » _es ) of the input variables (m to m) , which is proportional to the instantaneous value of the torque   is present, the facilities (7) for Multipli cation and the device (9) "for addition * Analog or digital working modules are and in digital mode, the multiplier £ 5 tion / s of institution (s) (7) and additions the device (9) are taken over by an electronic computer (29), at whose output (30) a digital signal is delivered and a device (31) for digital-to-analog conversion can be connected, whose output is an analogue Sends signal and the electronic computer (29) via control lines (33) bzrw. (34) is connected to the devices (3) and (4), 2. Torque measurement according to item 1, characterized in that in analog measurement some or all winding strands are located on the measuring device, the voltage drops (u ^) to (u _n ) at each device (3), bis- (3 _n ) as well as the strand currents (i ^) to (i _n ) at "one Device (4) "bis (4 _a > lie 'whose outputs are connected to the multipliers inrichtungen (7) to (7 _n ) and their outputs" (m ^) to On _n ) of an adder (9) are supplied, the the measurement signal (m _eg ) to "the output terminal (10) provides analog. 3. Drehmomentinsung solution according to item 1, characterized in that in digital measuring some or all winding strands are on the measuring device and the devices (3) to (3 _n ) and (4) to (4 _n ) include analog-to-digital converters and the devices (3) to (3 _n ) and (4) to (4 _n ) are monolithically integrated or hybrid or discrete and the outputs of the devices (3) to (3 _n > and (4) to (4 _n ) an are fed into an electronic computer (29), 4. Torque measurement according to item 1 and 2, characterized in that the devices (3) to (3 _n ), (4) to (4 _n ) and (9) in analog mode as monolithic integrated circuits such as operational amplifier and the device (7 ) are designed as four-quadrant multipliers For this 1 sheet drawings