Title of Invention	SPINNING MACHINE WITH FREQUENCY CONVERTERS
Abstract	The invention relates to electronic components (9, 10) in spinning machines, i.e. components such as frequency converters and the like, which develop so much heat that they require cooling. Said electronic components are therefore provided with cooling fins (3) that protrude into the exhaust air flow (2) which removes fly, dust and other impurities from the spinning area by suction. The impurities contained in the exhaust air flow (2) are removed in a filter (5) which, as a result, becomes increasingly clogged. The volume and cooling effect of the filter are thus reduced. In order to nevertheless prevent overheating of the electronic components (9, 10), the latter are provided with thermal sensors (17) which, in the event of an excessive temperature increase, emit a signal to a control device (12) thereby alerting the user of the necessity to clean the filter. The information can be provided progressively and, as a last resort, the power supply of the electronic components switched off or the drives are stopped.

Title of Invention

SPINNING MACHINE WITH FREQUENCY CONVERTERS

Abstract

The invention relates to electronic components (9, 10) in spinning machines, i.e. components such as frequency converters and the like, which develop so much heat that they require cooling. Said electronic components are therefore provided with cooling fins (3) that protrude into the exhaust air flow (2) which removes fly, dust and other impurities from the spinning area by suction. The impurities contained in the exhaust air flow (2) are removed in a filter (5) which, as a result, becomes increasingly clogged. The volume and cooling effect of the filter are thus reduced. In order to nevertheless prevent overheating of the electronic components (9, 10), the latter are provided with thermal sensors (17) which, in the event of an excessive temperature increase, emit a signal to a control device (12) thereby alerting the user of the necessity to clean the filter. The information can be provided progressively and, as a last resort, the power supply of the electronic components switched off or the drives are stopped.

Full Text	FIELD OF INVENTION The invention relates to a spinning machine with electronic components, in particular frequency converters, which project with cooling ribs into an exhaust airstream routed in an exhaust air duct. BACK GROUND OF THE INVENTION Spinning machines have electronic components which generate so much heat that they require cooling. It is known to provide electronic components of this type with cooling surfaces which project into the exhaust airstream by means of which fly, dust, thread residues and the like are sucked away out of the spinning region. This presupposes that this exhaust airstream has sufficient volume. Since this exhaust airstream is freed of the entrained impurities by means of filters, its volume diminishes with an increasing coating of the filter. The cooling action brought about by it consequently also diminishes. Prior art EP 0 478 993 A1 discloses a method for cooling the driving units a method for cooling the driving units with power electronics of a ring spinning or twisting machine in a spinning room, in which the air is guided towards a heat exchanger (30) of the power electronics (16), is accelerated before it, is heated on it and discharged behind it to the outside through an outgoing air opening (13), characterized in that the air is a partial stream of the outgoing air of the machine, which partial stream is branched from the machine, which partial stream is branched from the main stream of the outgoing air and is discharged therefrom without producing any air streams in the spinning room. OBJECT OF THE INVENTION But in the present invention, the set object is to draw attention to rising temperatures in electronic components which may be caused by the increasing coating of the filter. It achieves this object by means of the features mentioned in the following description. Here the electronic components, in particular frequency converters, which project with cooling ribs into an exhaust airstream routed in an exhaust air duct, characterized in that the electronic components (9, 10) are provided with thermal sensors (17) which, in the event of an inadmissible rise in temperature in the electronic components, transmit a warning signal to a control device (12) which with a warning signal indicates the need for cleaning the at least one filter (5) in the exhaust airstream (2). This distinguishing feature is not disclosed in EP 0478993 A1. DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION In a first approach, it is presumed that an increase in temperature in electronic components is caused by an increase in coating of the filter with impurities and the resulting decrease in the volume of the exhaust airstream throughput. Attention is therefore drawn first to the need for cleaning the filter. When this cleaning has taken place and a raised temperature is nevertheless signaled, this must have other causes which have to be investigated. The indication of the need for cleaning the filter may take place in steps; in the last step the electronic components are switched off and the spinning machine is stopped, in order to avoid damage to the electronic components. The system of the arrangement is illustrated diagrammatically in the drawing in a top view of a spinning machine. A spinning machine, for example a ring spinning machine or a roving machine, has a suction- extraction duct 1, into which air laden with fly and/or dust is sucked in the direction 2 of the arrow, for example from thread break suction-extraction points not illustrated here, by means of a fan 3. After the fly- and/or dust-laden air has been picked up, it passes through a filter box 4, in which the entrained fly and dust is retained by one or more filters 5. The fan 3 can blow out the cleaned air into the spinning room again in the direction 6 of the arrow. Blow-out may also take place into the air conditioning system, so as not to load the spinning room with the discharged heat. The spinning machine contains a plurality of electric drive motors, of which two, identified by reference numerals 7 and 8, are illustrated here by way of example. These may be drive motors for spindles, for flyers or for other working members of the spinning machine. Let them be three-phase motors of variable rotational speed, the rotational speeds of which are determined by means of adjustable frequency converters 9 and 10. The network frequency supplied via a line 11 passes through a control device 12 and is supplied to the frequency converters 9 and 10 via lines 13. A rotational speed signal is imparted to the frequency converters 9 and 10 via control lines 14, and, in response to this signal, they control the frequency for operating the motors which is transmitted to the motors 7 and 8 via motor lines 15. The frequency converters 9 and 10 contain, inter alia, rectifiers and inverters which unavoidably generate heat and raise the temperature of the frequency converters during operation. In order to discharge this heat and prevent the frequency converters from overheating, they have cooling ribs 16 which project into the airstream prevailing in the suction-extraction duct 1. The heat generated is thus discharged by means of this airstream. Of course, instead of the waste heat from the frequency converters 9 and 10, the waste heat from other electrical or electronic structural units of the spinning machine may also be discharged by means of the airstream in the exhaust air duct 1, these structural units then likewise projecting with cooling ribs into this airstream. Thus, if the network supply of the spinning machine is by direct current, the structural units 9, 10 may comprise only inverters. A sufficiently heat-discharging and cooling airstream 2 in the suction-extraction duct 1 is afforded only when its volume is not throttled excessively due to the coating of the filter 5 with fly and dust. It is therefore necessary to clean the filter from time to time or regularly, that is to say to free it of its coating. If this is neglected, this may lead, due to a lack of sufficient heat discharge, to an overheating and failure of the electrical or electronic subassemblies, that is to say, for example, of the frequency converters 9, 10. In order to ensure that this is prevented, the electronic subassemblies 9, 10 are provided with thermal sensors 17 which transmit a signal to the control device 12 via the signal lines 18 or 19 when a predetermined temperature is overshot. The signal may be coded as a function of the height of the temperature reached, that is to say, for example, may become higher with a rising temperature. The reaction of the control device to this signal may take place in steps. First, the control device 12 can indicate the need for cleaning the filter 5 on a display 20. If this is not complied with in a specific time or if the signal continues to signal a raised temperature, the need for cleaning can be indicated by means of an optical indicator apparatus 21 or by means of an acoustic signal. If the temperature in one or more of the electronic subassemblies does not decrease even after a cleaning of the filter 5, this must have another cause which must be investigated. If the temperature in one of the electrical or electronic subassemblies reaches a height threatening to cause it to fail, the control device 12 can ultimately interrupt the network feed - for this purpose, the network feed line 11/13 is routed through this control device. In many cases, however, it is more expedient if the control device stops the drives in a controlled way. Faults, such as, for example, thread breaks, are thereby avoided. The cooling ribs 16 of the electrical or electronic subassemblies 9, 10 project in the direction of the airstream through the suction-extraction duct 1, downstream of the filter box 4, into the suction- extraction duct and therefore into the cleaned airstream, so that they are not clogged with fly and dust. The suction-extraction duct advantageously has in this region a planar wall into which the cooling ribs can easily be inserted. The cooling ribs 16 project into the cleaned airstream and are therefore not exposed to contamination. However, since, as a rule, the filter 5 does not retain fine dust, orifices closed by means of removable covers 22 are arranged on that side of the suction-extraction duct 1 which lies opposite the cooling ribs, the cooling ribs being accessible through these orifices so that they can occasionally be cleaned of fine dust. List of reference numerals 1 Suction-extraction duct 2 Direction of arrow 3 Fan 4 Filter box 5 Filter 6 Direction of arrow 7 Drive motor 8 Drive motor 9 Frequency converter 10 Frequency converter 11 Network line 12 Control device 13 Network line 14 Control lines 15 Motor lines 16 Cooling ribs 17 Thermal sensor 18 Signal line 19 Signal line 20 Display 21 Optical indicator apparatus 22 Orifices WE CLAIM 1. A spinning machine with electronic components, in particular frequency converters, which project with cooling ribs into an exhaust airstream routed in an exhaust air duct, characterized in that the electronic components (9, 10) are provided with thermal sensors (17) which, in the event of an inadmissible rise in temperature in the electronic components, transmit a warning signal to a control device (12) which with a warning signal indicates the need for cleaning the at least one filter (5) in the exhaust airstream (2). 2. The spinning machine as claimed in claim 1, wherein the control device (12), in a first warning step, indicates on a display the need for cleaning the at least one filter (5) in the exhaust airstream. 3. The spinning machine as claimed in claim 1, wherein the control device (12) in a second warning step indicates by means of an optical and/or acoustic warning apparatus (21) the need for cleaning the at least one filter (5) in the exhaust airstream (2). 4. The spinning machine as claimed in claim 1, wherein the control device (12) in a third warning step interrupts the power supply of the electronic components (9, 10) or stops the drives in a controlled way. 5. The spinning machine as claimed in claim 1, wherein the cooling ribs (16) of the electronic components (9, 12) project, downstream of the filter box (4) in the direction of flow of the exhaust airstream (2), into the cleaned exhaust airstream. 6. The spinning machine as claimed in claim 1, wherein the suction-extract duct (1) has a planar wall at least in the region in which cooling ribs (16) project into it. 7. The spinning machine as claimed in claim 1, wherein the suction-extraction duct (1) has, opposite the region in which cooling ribs (16) project into it, an orifice which is closed by means of a cover (22) and through which the cooling ribs are accessible for cleaning. ABSTRACT SPINNING MACHINE WITH FREQUENCY CONVERTERS The invention relates to electronic components (9, 10) in spinning machines, i.e. components such as frequency converters and the like, which develop so much heat that they require cooling. Said electronic components are therefore provided with cooling fins (3) that protrude into the exhaust air flow (2) which removes fly, dust and other impurities from the spinning area by suction. The impurities contained in the exhaust air flow (2) are removed in a filter (5) which, as a result, becomes increasingly clogged. The volume and cooling effect of the filter are thus reduced. In order to nevertheless prevent overheating of the electronic components (9, 10), the latter are provided with thermal sensors (17) which, in the event of an excessive temperature increase, emit a signal to a control device (12) thereby alerting the user of the necessity to clean the filter. The information can be provided progressively and, as a last resort, the power supply of the electronic components switched off or the drives are stopped.

Full Text

FIELD OF INVENTION
The invention relates to a spinning machine with electronic components, in particular frequency
converters, which project with cooling ribs into an exhaust airstream routed in an exhaust air duct.
BACK GROUND OF THE INVENTION
Spinning machines have electronic components which generate so much heat that they require
cooling. It is known to provide electronic components of this type with cooling surfaces which project
into the exhaust airstream by means of which fly, dust, thread residues and the like are sucked away
out of the spinning region. This presupposes that this exhaust airstream has sufficient volume. Since
this exhaust airstream is freed of the entrained impurities by means of filters, its volume diminishes
with an increasing coating of the filter. The cooling action brought about by it consequently also
diminishes.
Prior art EP 0 478 993 A1 discloses a method for cooling the driving units a method for cooling the
driving units with power electronics of a ring spinning or twisting machine in a spinning room, in which
the air is guided towards a heat exchanger (30) of the power electronics (16), is accelerated before it,
is heated on it and discharged behind it to the outside through an outgoing air opening (13),
characterized in that the air is a partial stream of the outgoing air of the machine, which partial
stream is branched from the machine, which partial stream is branched from the main stream of the
outgoing air and is discharged therefrom without producing any air streams in the spinning room.
OBJECT OF THE INVENTION
But in the present invention, the set object is to draw attention to rising temperatures in electronic
components which may be caused by the increasing coating of the filter. It achieves this object by
means of the features mentioned in the following description. Here the electronic components, in
particular frequency converters, which project with cooling ribs into an exhaust airstream routed in an
exhaust air duct, characterized in that the electronic components (9, 10) are provided with thermal
sensors (17) which, in the event of an inadmissible rise in temperature in the electronic components,
transmit a warning signal to a control device (12) which with a warning signal indicates the need for

cleaning the at least one filter (5) in the exhaust airstream (2). This distinguishing feature is not
disclosed in EP 0478993 A1.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION
In a first approach, it is presumed that an increase in temperature in electronic components is caused
by an increase in coating of the filter with impurities and the resulting decrease in the volume of the
exhaust airstream throughput. Attention is therefore drawn first to the need for cleaning the filter.
When this cleaning has taken place and a raised temperature is nevertheless signaled, this must have
other causes which have to be investigated.
The indication of the need for cleaning the filter may take place in steps; in the last step the electronic
components are switched off and the spinning machine is stopped, in order to avoid damage to the
electronic components.
The system of the arrangement is illustrated diagrammatically in the drawing in a top view of a
spinning machine.
A spinning machine, for example a ring spinning machine or a roving machine, has a suction-
extraction duct 1, into which air laden with fly and/or dust is sucked in the direction 2 of the arrow,
for example from thread break suction-extraction points not illustrated here, by means of a fan 3.
After the fly- and/or dust-laden air has been picked up, it passes through a filter box 4, in which the
entrained fly and dust is retained by one or more filters 5. The fan 3 can blow out the cleaned air into
the spinning room again in the direction 6 of the arrow. Blow-out may also take place into the air
conditioning system, so as not to load the spinning room with the discharged heat.
The spinning machine contains a plurality of electric drive motors, of which two, identified by
reference numerals 7 and 8, are illustrated here by way of example. These may be drive motors for
spindles, for flyers or for other working members of the spinning machine. Let them be three-phase
motors of variable rotational speed, the rotational speeds of which are determined by means of
adjustable frequency converters 9 and 10. The network frequency supplied via a line 11 passes
through a control device 12 and is supplied to the frequency converters 9 and 10 via lines 13. A
rotational speed signal is imparted to the frequency converters 9 and 10 via control lines 14, and, in
response to this signal, they control the frequency for

operating the motors which is transmitted to the motors
7 and 8 via motor lines 15.
The frequency converters 9 and 10 contain, inter alia,
rectifiers and inverters which unavoidably generate
heat and raise the temperature of the frequency
converters during operation. In order to discharge this
heat and prevent the frequency converters from
overheating, they have cooling ribs 16 which project
into the airstream prevailing in the suction-extraction
duct 1. The heat generated is thus discharged by means
of this airstream.
Of course, instead of the waste heat from the frequency
converters 9 and 10, the waste heat from other
electrical or electronic structural units of the
spinning machine may also be discharged by means of the
airstream in the exhaust air duct 1, these structural
units then likewise projecting with cooling ribs into
this airstream. Thus, if the network supply of the
spinning machine is by direct current, the structural
units 9, 10 may comprise only inverters.
A sufficiently heat-discharging and cooling airstream 2
in the suction-extraction duct 1 is afforded only when
its volume is not throttled excessively due to the
coating of the filter 5 with fly and dust. It is
therefore necessary to clean the filter from time to
time or regularly, that is to say to free it of its
coating. If this is neglected, this may lead, due to a
lack of sufficient heat discharge, to an overheating
and failure of the electrical or electronic
subassemblies, that is to say, for example, of the
frequency converters 9, 10.
In order to ensure that this is prevented, the
electronic subassemblies 9, 10 are provided with
thermal sensors 17 which transmit a signal to the

control device 12 via the signal lines 18 or 19 when a
predetermined temperature is overshot. The signal may
be coded as a function of the height of the temperature
reached, that is to say, for example, may become higher
with a rising temperature. The reaction of the control
device to this signal may take place in steps.
First, the control device 12 can indicate the need for
cleaning the filter 5 on a display 20. If this is not
complied with in a specific time or if the signal
continues to signal a raised temperature, the need for
cleaning can be indicated by means of an optical
indicator apparatus 21 or by means of an acoustic
signal. If the temperature in one or more of the
electronic subassemblies does not decrease even after a
cleaning of the filter 5, this must have another cause
which must be investigated.
If the temperature in one of the electrical or
electronic subassemblies reaches a height threatening
to cause it to fail, the control device 12 can
ultimately interrupt the network feed - for this
purpose, the network feed line 11/13 is routed through
this control device. In many cases, however, it is more
expedient if the control device stops the drives in a
controlled way. Faults, such as, for example, thread
breaks, are thereby avoided.
The cooling ribs 16 of the electrical or electronic
subassemblies 9, 10 project in the direction of the
airstream through the suction-extraction duct 1,
downstream of the filter box 4, into the suction-
extraction duct and therefore into the cleaned
airstream, so that they are not clogged with fly and
dust. The suction-extraction duct advantageously has in
this region a planar wall into which the cooling ribs
can easily be inserted.

The cooling ribs 16 project into the cleaned airstream
and are therefore not exposed to contamination.
However, since, as a rule, the filter 5 does not retain
fine dust, orifices closed by means of removable covers
22 are arranged on that side of the suction-extraction
duct 1 which lies opposite the cooling ribs, the
cooling ribs being accessible through these orifices so
that they can occasionally be cleaned of fine dust.

List of reference numerals
1 Suction-extraction duct
2 Direction of arrow
3 Fan
4 Filter box
5 Filter
6 Direction of arrow
7 Drive motor
8 Drive motor
9 Frequency converter
10 Frequency converter
11 Network line
12 Control device
13 Network line
14 Control lines
15 Motor lines
16 Cooling ribs
17 Thermal sensor
18 Signal line
19 Signal line
20 Display
21 Optical indicator apparatus
22 Orifices

WE CLAIM
1. A spinning machine with electronic components, in particular frequency converters,
which project with cooling ribs into an exhaust airstream routed in an exhaust air
duct, characterized in that the electronic components (9, 10) are provided with
thermal sensors (17) which, in the event of an inadmissible rise in temperature in
the electronic components, transmit a warning signal to a control device (12)
which with a warning signal indicates the need for cleaning the at least one filter
(5) in the exhaust airstream (2).
2. The spinning machine as claimed in claim 1, wherein the control device (12), in a
first warning step, indicates on a display the need for cleaning the at least one
filter (5) in the exhaust airstream.
3. The spinning machine as claimed in claim 1, wherein the control device (12) in a
second warning step indicates by means of an optical and/or acoustic warning
apparatus (21) the need for cleaning the at least one filter (5) in the exhaust
airstream (2).
4. The spinning machine as claimed in claim 1, wherein the control device (12) in a
third warning step interrupts the power supply of the electronic components (9,
10) or stops the drives in a controlled way.

5. The spinning machine as claimed in claim 1, wherein the cooling ribs (16) of the
electronic components (9, 12) project, downstream of the filter box (4) in the
direction of flow of the exhaust airstream (2), into the cleaned exhaust airstream.
6. The spinning machine as claimed in claim 1, wherein the suction-extract duct (1)
has a planar wall at least in the region in which cooling ribs (16) project into it.
7. The spinning machine as claimed in claim 1, wherein the suction-extraction duct
(1) has, opposite the region in which cooling ribs (16) project into it, an orifice
which is closed by means of a cover (22) and through which the cooling ribs are
accessible for cleaning.

ABSTRACT

SPINNING MACHINE WITH FREQUENCY CONVERTERS
The invention relates to electronic components (9, 10) in spinning machines, i.e.
components such as frequency converters and the like, which develop so much heat that
they require cooling. Said electronic components are therefore provided with cooling fins
(3) that protrude into the exhaust air flow (2) which removes fly, dust and other
impurities from the spinning area by suction. The impurities contained in the exhaust air
flow (2) are removed in a filter (5) which, as a result, becomes increasingly clogged. The
volume and cooling effect of the filter are thus reduced. In order to nevertheless prevent
overheating of the electronic components (9, 10), the latter are provided with thermal
sensors (17) which, in the event of an excessive temperature increase, emit a signal to a
control device (12) thereby alerting the user of the necessity to clean the filter. The
information can be provided progressively and, as a last resort, the power supply of the
electronic components switched off or the drives are stopped.

SPINNING MACHINE WITH FREQUENCY CONVERTERS

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