JPS5959044A - Interface circuit for indicating wear of brush - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an interface electrical circuit for isolating a plurality of detected electric power from an indicator circuit, and more particularly, an interface electrical circuit between a brush wear indicator circuit and a 'fU number of brush wear cleaners. This invention relates to an interface circuit used between the two.

In rotary electric machinery equipped with brushes, brush wear occurs during operation. Various sensors are used to monitor whether a certain degree of brush wear has occurred and to issue a signal. A number of different types of brush wear indicating devices are known prior to the present invention, such as U.S. Pat. In general, a number of conventional brush wear indicating devices are disclosed in the above-mentioned special i1F.
It is described in several patents cited in the application. Specific examples of conventional and well-known brush wear indicator sensor devices are provided below in conjunction with the description of the present invention. There are a number of different types of indicator or alarm circuits that are particularly suitable for use with these brush wear indicator devices. like this'
Some of the tf circuits are, for example, US Pat. No. 3,523.
2ε38 (issued August 4, 1970 (1)). As described in this patent, a normally on or normally off indicating alarm means is provided, and the alarm means is connected to a monitored In response to the occurrence of a predetermined degree of wear on the brushes in use, the switch will switch from one state to another.
It is generally well known to construct a brush wear indicating circuit of this type.

Also, U.S. Special Forces 1st Bow No. 4,024,525 (May 1977)
The brush wear indication circuit C disclosed in the publication (published on May 17th) monitors the wear occurring on multiple brushes at the same time, and also activates one signal indication or generates an alarm signal. Indicates that one or more brushes have experienced a predetermined degree of wear. Selective actuation of the indicator is controlled by a control circuit connected between the brush mill and the indicator.

A common problem encountered with currently known brush wear indicator devices and associated indicator alarm or signal circuits is that the human input signal transmitted to the indicator circuit is often unreliable or undesirable. In addition, many conventional brush wear indicator devices are limited in their ability to utilize the current flowing through the brush being monitored. J: The brush current often fluctuates quite erratically when the brushes are considerably worn and the contact with the commutator in which they are installed becomes uneven.

Further, in a brush wear indicator circuit that uses the voltage of the brush being monitored to generate an indicator signal, a voltage sensitive element in a coupling circuit between the brush wear sensor and the indicator circuit, or an indicator means itself, is used. The high voltage peaks that occur on the brushes that are being monitored can cause damage. Set up an appropriate interface circuit for use (
(1) Provides an efficient and reliable means to create a new brush wear indication system or to improve an existing brush wear indication system so as to avoid some of the above problems. That is desirable.

Therefore, it is a principal object of the present invention to overcome the problems described above (over conventional brush wear indicator devices and associated circuits suitable for use between a number of brush wear sensors and an indicator circuit that provides an alarm). The object of the present invention is to provide an interface circuit that can avoid C.

Another object of the present invention is to provide an interface circuit (11?) for use between a plurality of brush wear sensors and an indicator circuit. The purpose of this invention is to effectively isolate the indicator circuit from voltage surges that could cause damage to the brushes being monitored by the sensor device.

It is a further object of the present invention to provide an interface circuit useful for use with a variety of different brush wear indicator devices and a variety of different indicator alarm circuits, the interface circuit being useful for use with a variety of different brush wear indicator devices and any manual input of a suitably connected brush wear indicator device. The object is to provide a means for safely and reliably operating any one of the alarm circuits from lj,i.

Yet another object of the present invention is to provide one of four brush-wearing lenses for supplying human power signals to the internocourse circuit.
The purpose of the present invention is to provide an interface circuit that operates to latch (hold) an S signal in an indicated state in response to one or more sensor numbers. It is irrelevant whether the brush being monitored by the hinge is energized or disconnected from it.

Further objects and advantages of the present invention will become apparent from the following description in conjunction with the accompanying drawings.

An interface circuit in accordance with a preferred embodiment of the present invention is responsive to a PANO] signal from one or more of a plurality of brush wear indicating devices operatively associated with brushes of a rotating electrical machine, such as a DC motor. The middle alarm circuit (=i'
/3? It is effective for The ace circuit includes an optically coupled isolator whose output is connected to an indicator alarm circuit and connected to the output of a diode/ridge circuit where human power connects a plurality of human power connection points. .

Two of the power connection points of the die A-dozer are each connected to a brush wear sensor, and the input connection point of the pond is connected to the center point of the resistor bridge.

The resistive bridge includes a connection point connected in series with a pair of brushes that are monitored by a brush wear sensor. This interface circuit responds to the occurrence of significant wear on either or both of the brushes associated with the hinge armor due to the brush wear sensor 1. operative to activate a single alarm in the indicating circuit in response to a signal generated or transmitted by the indicating circuit; Once activated, the alarm is latched "on" and remains activated even when power is removed from the brush being monitored by the wear indicator.

Additional brush wear can be easily installed (4) by adding a 1-grade diode to the tie auto bridge for each additional lenght, and inserting an additional 1" diode between the diodes. Connect the points.

Preferred embodiments of the present invention will be explained with reference to the accompanying drawings.

In the drawing, an IC interface circuit 1 configured according to the present invention is shown surrounded by a chain line.

In order to facilitate understanding of the present invention, the interface circuit 1 is shown as being arranged in an operational relationship with respect to the DC motor 2J and the indicating circuit 3. In the configuration shown, the interface circuit 1 is operative to transmit signals from brush wear sensors mounted in operational relationship with each brush of the motor 2 to activate an alarm, e.g. a signal light, in the indicator circuit 3. .

It will be clear that a number of different types of rotating electric machines J3 and associated current-carrying brushes can be combined with the interface circuit 1 of the invention. Likewise, a variety of different forms of indicator circuits ( For example, circuit 3) can be used in combination with the interface circuit 1 of the present invention.Thus, circuit 2 and its associated control equipment, power supply and brush wear sensor 1 are simplified in the drawings. −
Similarly, the instruction circuit 3 is also abbreviated as ffO and shown as C-(d6.A person skilled in the art will be able to combine it with the interface circuit of the present invention in place of b, which is integrally described herein). Being able to use other types of circuits and equipment
You should be able to solve 11. As shown in FIG. is a battery and is operatively connected to a suitable DC power source 6. Suitable conventional motor control means 7 are inserted into this series circuit to complete a simple DC motor circuit of the known type.

A pair of brush wear lenses 8 and 8' are mounted in association with motor brushes 4 and 5 to generate or transmit electrical signals in response to a predetermined degree of wear on one or both brushes. constitute means. It is preferable to refer to brush wear sensor 4-8 a3 and 8' as having the same form, but when applying the C1 wood invention to a specific use for purposes other than economy through standardization, internal maintenance and operation, they may have different forms. It's lil that I can use the form of Leno 1no! It will be understood. In the embodiment of the invention described hereinabove, each of the brushes is parallel to the oriented axis of the associated brush, and the insulating material is embedded in the brush. Cut the conductor. During operation, the brush reaches a predetermined degree.
As it ages, the insulator around the buried conductor wears down as the brush wears, so the innermost end of the buried conductor becomes in a conductive relationship with the DC Tanabata 2 rectifier. . When such a predetermined degree of brush wear occurs, a current flows through the buried conductor, and this signal current is transferred from the buried conductor to the associated brush wear ring 8 or 8.
- is sent to the interface circuit 1.

Before explaining the features of the interface circuit 1, the instruction circuit 3 shown in a simplified form in the drawings will be briefly explained. In the illustrated format of the indicator circuit 33, the alarm lamp 9 is electrically connected in series to the manual switch 10J3 and the secondary voltage 11jl, and the secondary voltage; The indicator alarm of the indicator circuit 3 does not have to be a lamp C, but can be connected to a horn, bell or other conventional type of signal indicator. The operation of these indicators is determined by determining the operation of the interface circuit 1 in the same manner as the operation of the instruction circuit 3, which will be described in detail later.

Those skilled in the art will appreciate that the indicating circuit 3 does not necessarily include a switch such as switch 10 or an auxiliary power source such as a battery 11, depending on the application. Obviously, it would be possible to provide a suitable indication alarm for the indication circuit 3 in the form shown.
, Detailed Description of the Invention - 15 minutes, useful for beating the present invention. The indicator circuit can be used to emit an indicator signal that is powered by power derived from the commutator stream of the machine being monitored, or is completely separate from the machine being monitored. [l?[
It is possible to operate the road. Furthermore, using such a separate power supply for the indication alarm 1. In this case, if 5CR1b" becomes conductive due to human intervention due to the wear of the brush, the alarm remains activated due to the holding action of 5CR15".

C motor 2 and related brush wear + J-8
, ε3-OJ, and other relatively conventional control circuits, and have described a suitable simple indicator circuit 3, a preferred interface circuit 1 of the present invention has been described. An example of the circuit configuration will be explained.

The interface circuit 1 in the form shown in FIG.
Contains C. A typical tie A-to-solage circuit 13 has a plurality of input connections 13G, 13C'J> and 13C' and a pair of output connections 13A and 13B, with six connections as shown. Diodes 14A to 14F- are 1
Pair of output connection points 13△, 1313, etc., three input connection points 1
3G, , 13C'-, 13C''. Here, an additional brush wear sensor can be easily connected to C circuit 1 (
= J configuration (recognizing that there is a disconnection, i.e., one additional pair of diodes for each additional diode (not shown)) is connected to the illustrated diode pair 11j1 at connection points 13A and 13.
A sensor can be easily attached by connecting and covering between B.

Of course, 13 from the midpoint of the conductor between the additional diode pairs.
C"J> J, : Make appropriate connections similar to those shown in 13C". With these changes, circuit 1
can be used to monitor four, six or more brushes on a first machine, or to monitor brushes on several separate machines.

Finally, the interface circuit 1 is an optical coupling isolator 1
Contains 5. Input terminals 15△ and 15B of isolator 1 (5 are connected to the output connection point 13Acl of the diode
A suitable current-limiting stage, for example a resistor 16, is connected in series with the isolator input terminals 15A and 15) 13, respectively electrically connected to the isolator elements 15A and 1313. protects the device from overcurrent damage.

Of course, in other embodiments, resistor 16 may be replaced by a field effect diode or other suitable current constant device to provide the desired current limiting function of C1. Isolator 1! l)
The output terminals 15C and 15D of are electrically connected to appropriate associated communication means (for transmitting signals to the latter. In the illustrated example, the indicating circuit 3 connects these output terminals 1ξi Ci15 J,
and '15D, and responds to the operation of optical coupling isolator 1b.

It is understood that in the interface circuit 1 of the present invention, the particular type of isolator 15 shown may be replaced with any six of a number of suitable commercially available isolators. However, in the preferred embodiment of the present invention, isolator 15 is a commercially available hand-operated type isolator sold by General Electric Corporation under the trade designation GHI-1'11 G3. In such an isolator, as shown in the figure, the light emitting diode 1F) is connected to S.
R1:〕〕　　　　　　　　　　　　　　　　To control the biasing sensitivity of isolator 15, bias resistor 17 is toured as shown.
Electrical connection is made to the output circuit of the sorator 15.

The InternoAce circuit 1 of the present invention can be combined with other devices in various ways! Although it can be used for any desired purpose, in the illustrated preferred embodiment of the present invention, the interface 1-2 circuit 1
is connected to DC heater 2 J5 and its associated pair of brush wear sensors 8.8-.
The brushes 4 and d5 are connected in series with the resistor bridge 12, and the midpoint voltage from the brushes 1 and 5 appears at the midpoint voltage connection point 12C, and the input connection point 1 of the diode bridge 13; Applied to 3C. Brush wear sensors 8 and 8' output signals to two other brush wear sensors when one or both of them (8d3 and 8') detect a predetermined degree of wear of the related brush (4 or 55). The preferred combination includes a DC power supply 6, which is connected to the motor control means 7 as well as the brushes 4 and 5 is operatively connected to the motor.

Finally, the illustrated suitable combination V of the present invention includes an indicator circuit 3.
is included, and the alarm 9 of this indicator circuit 3, such as a voltage coupler or a U-lamp, is optically coupled)' Output terminal 15CJj of the isolator 15 C1! ][) and connected to direct 11C
There is. As mentioned above, this embodiment of the present invention has a battery 1.
The auxiliary DC power supply of the form No. 1 is electrically connected in series with the single-acting switch 10J3 and the indicator lamp 9, so that (-1 indicator lamp ≦) the C
It works. That is, when the isolator 15 is activated and the C battery and 7 RAM circuit are closed to form a series loop, power is supplied to the alarm 9. Of course, the single-acting switch 10 (e.g., by pulling or pulling the starting key switch on the truck to be operated by the battery C' on which the DC motor 2 is mounted) is closed when the DC motor 2 is started (i.e., the indicator circuit The number 3 is put into a state where it appears to be a monkey.

Advantages of this preferred embodiment of the present invention (J, isolator 1
5 SC [15'' switches switch 10 to Gtl
It remains in a conductive state. Therefore, C, brush wear sensor →) 8 or 8- sends a signal indicating the occurrence 11 of the above-mentioned degree of wear of the associated brush 4 or 5 to the connection point of the diode bridge 13. 13C″ or 13C″
There is no need to keep sending to either one. In fact, alarm 9
After being activated, the power is cut off from the brushes/IJ'-3 and b, in which case SCI'<15'' continues to supply power to the alarm 9 from the battery 11.

The start input signal from the wires 8 and 8" will be either positive or zero when the signal sent from the brush wear sensor reaches the diode bridge connection points 133C- and 13C". Regardless, the instruction alarm 9 is activated.If only one of the sensors C, 8 and 8' exhibits a predetermined degree of brush wear, C also SCR15" is activated, the C alarm lamp 9 lights up, and the lamp remains lit until the operator stops the alarm transmission. Normally, the operator can stop the alarm immediately after replacing the worn brush. This is done by listening to 10 poetically.

From the above description of the present invention, those skilled in the art will recognize that various other forms of the present invention and changes to the preferred embodiments described above may be made within the scope of the present invention. There is a certain thing that I understand.

[Brief explanation of the drawing]

The drawing shows a non-turf circuit according to the invention, an associated brush wear hinge device, a DC motor d3 for controlling a plurality of brushes, and a signal indicating alarm circuit.
be. 1...Interface circuit, 2...
DC motor, 3... Indication circuit, 4.5... Brush, 6... DC power supply, 7... Monitor control means, 8.8-... ...Brush wear sensor 9...
Alarm lamp, 10...Manual switch, 11...Auxiliary DC power supply, 12...Resistance circuit,

Claims (1)

[Scope of Claims] 1. A plurality of independently operating brush wear units each generating or transmitting an electrical signal in response to a predetermined degree of wear occurring on an associated brush. The interface circuit used between the iJ3 and the indicating circuit includes a resistor bridge circuit having an intermediate voltage connection point, and a die Δ゛-bridge circuit C that connects a plurality of input connection points and a pair of output connection points. one power connection point is electrically connected to the midpoint voltage connection point of the resistor bridge, and the other power connection points each include a die connectable to receive a signal from one of the brush wear centers. Vice-
The optically coupled isolator C has a bridge circuit, an input terminal, and an output terminal.
– the output connection point of the bridge (each electrically connected to
In response to the activation of this optical coupling isolator, the output terminal -
and an optical coupling isolator that can be electrically connected to transmit signals to the two-finger subcircuit. 2. The interface circuit according to claim 1, wherein a bias resistor is electrically connected to the output circuit of the optically coupled isolator to control the operating sensitivity of the C isolator. 3. The interface circuit according to claim 2, wherein the current limiting means is electrically connected in series to the input terminal of the optically coupled isolator. 4. The interface circuit connects multiple public brushes 4.
EJ? A direct current machine J3 is mounted on an operating IMj, each associated with one of said brushes, and used in conjunction with a plurality of brush wear sensors, said brushes being connected in series with said resistor bridge, said brushes being connected in series with said resistor bridge, said In response to any or all of the lenses detecting a predetermined degree of wear on each associated lens, the sensor sends a signal to the other manual connection points of the die bridge. special 8
'(Interface L-circuit according to claim 411. 5. The DC power supply is connected to the upper 11C for driving the
operatively connected to the brush, said indicating circuit comprising an alarm electrically connected in series with the output terminal of said optical coupling isolator, said alarm being actuated in response to actuation of said isolator; The interface circuit according to claim 4, which indicates that a predetermined degree of wear has occurred in Takezen-C. 6. An auxiliary DC power supply is electrically connected in series with the alarm and supplies power to the alarm when the alarm is activated by the action of the isolator.
Interface circuit described in section. 7. The optical coupling isolator includes an SGR, and the SGR
7. The interface circuit according to claim 6, wherein the CR remains conductive and continues to operate the alarm until the CR shuts off the power supply from the auxiliary power source to the SCR.