Classifications

• • D—TEXTILES; PAPER
  • D03—WEAVING
  • D03D—WOVEN FABRICS; METHODS OF WEAVING; LOOMS
  • D03D47/00—Looms in which bulk supply of weft does not pass through shed, e.g. shuttleless looms, gripper shuttle looms, dummy shuttle looms
  • D03D47/12—Looms in which bulk supply of weft does not pass through shed, e.g. shuttleless looms, gripper shuttle looms, dummy shuttle looms wherein single picks of weft thread are inserted, i.e. with shedding between each pick
• • D—TEXTILES; PAPER
  • D03—WEAVING
  • D03D—WOVEN FABRICS; METHODS OF WEAVING; LOOMS
  • D03D47/00—Looms in which bulk supply of weft does not pass through shed, e.g. shuttleless looms, gripper shuttle looms, dummy shuttle looms
  • D03D47/27—Drive or guide mechanisms for weft inserting
  • D03D47/271—Rapiers
  • D03D47/272—Rapier bands
• • D—TEXTILES; PAPER
  • D03—WEAVING
  • D03D—WOVEN FABRICS; METHODS OF WEAVING; LOOMS
  • D03D47/00—Looms in which bulk supply of weft does not pass through shed, e.g. shuttleless looms, gripper shuttle looms, dummy shuttle looms
  • D03D47/27—Drive or guide mechanisms for weft inserting
  • D03D47/275—Drive mechanisms
  • D03D47/276—Details or arrangement of sprocket wheels
• • D—TEXTILES; PAPER
  • D03—WEAVING
  • D03D—WOVEN FABRICS; METHODS OF WEAVING; LOOMS
  • D03D47/00—Looms in which bulk supply of weft does not pass through shed, e.g. shuttleless looms, gripper shuttle looms, dummy shuttle looms
  • D03D47/27—Drive or guide mechanisms for weft inserting
  • D03D47/277—Guide mechanisms

Definitions

• the invention relates to a method and a device for monitoring the wear of a rapier belt of a rapier weaving machine.
• the invention has for its object to provide a method and an apparatus for monitoring the wear of a gripper belt, which is not dependent on a special design of the gripper belt and / or the guides.
• This object is achieved in that the temperature of the gripper belt and / or of a component in contact with the gripper belt is evaluated as a parameter of the wear of the gripper belt.
• the inventors have recognized that the temperature of a gripper belt and also of a component which is in contact with the gripper belt changes during operation depending on the wear of the gripper belt. This effect is used to determine the state of wear of the gripper belt via the temperature of the gripper belt and / or a component in contact with the gripper belt.
• This method of monitoring is practically independent of the shape of the gripper belt and the shape of the guides. It is therefore possible to optimally design the structure of the gripper belt and the shape of guide elements for the gripper belt in order to guide the gripper belt exactly, since the point in time at which the gripper belt is worn out to such an extent that the desired function no longer functions can be recorded is certain.
• the temperature of the gripper belt is recorded directly. This can be done, for example, by means of an infrared detector arranged at a suitable location. In practice, however, it is sufficient in most cases if the temperature of the gripper belt is recorded indirectly. It is advantageous if the temperature of a component is recorded on which the gripper belt is guided.
• the temperature difference between the directly or indirectly recorded temperature of the gripper belt and a temperature recorded at a measuring point located at a distance from it is evaluated. In this way, the influence of the ambient temperature is eliminated.
• the object on which the invention is based is achieved by means of a device in which an evaluation device is provided which evaluates the temperature of the gripper belt and / or of a component in contact with the gripper belt as a parameter of the wear of the gripper belt.
• a first temperature sensor which detects the temperature in the immediate vicinity of the gripper belt
• a second temperature sensor are connected to the evaluation device, which detects the temperature at a point at a distance from it.
• the first temperature sensor is assigned to a guide block that holds the gripper belt in engagement with a drive wheel. This area is outside the shed and is therefore easily accessible. It is advantageously provided that a body made of heat-conducting material is attached to the guide block and receives the first temperature sensor at a point facing the guide block and the second temperature sensor at a point away from the guide block. The temperature sensors are protected inside the body so that the risk of damage is very low.
• the evaluation device is assigned an input device for entering a comparison value. By means of the input device, the operator can input a value which is compared by the evaluation device with the detected temperature or the recorded temperature behavior and when it is reached there is such wear on the gripper belt that an exchange should take place.
• a display is connected to the evaluation device, which indicates the state of wear of the gripper belt. The operator can thus recognize or even be made aware of when the rapier belt has to be exchanged in order to continue to ensure optimal weaving conditions.
• FIG. 1 shows a section of a rapier weaving machine with a drive wheel and a device for detecting the state of wear of a rapier belt
• Fig. 2 shows a section along the line II-II of Fig. 1 and
• Fig. 3 is a partial section similar to Fig. 1 of a modified embodiment.
• the part of a rapier weaving machine shown in FIG. 1 contains a rapier belt 1, which is provided in a manner not shown with a rapier which is used to insert weft threads into a shed of the rapier weaving machine.
• the gripper belt 1 is driven by means of a back and forth drive wheel 2. As can be seen from Fig. 2, is the gripper belt 1 is provided with holes at regular intervals into which teeth of the drive wheel 2 engage.
• the gripper belt 1 is held on the circumference of the drive wheel 2 by means of plate-like guide elements 3, 4 such that the teeth of the drive wheel 2 remain in engagement with the row of holes in the gripper belt 1.
• the plate-shaped guide elements 3, 4 are aligned essentially tangentially to the drive wheel 2. They are attached to bodies 5, 13 which in turn are fastened to the frame of the rapier weaving machine by means of holding means, not shown.
• a first temperature sensor 6 is arranged in the body 5. This temperature sensor 6 is arranged in the region of the point at which the gripper belt 1 is deflected from the horizontal direction in the circumferential direction to the drive wheel 2. The temperature sensor 6 is arranged in the vicinity of the guide element 3, so that it detects the temperature of the guide element 3 and thus indirectly also the temperature of the gripper belt 1.
• a second temperature sensor 7 serves to eliminate the influence of the ambient temperature. It is also arranged in the body 5, but at a point which is not so strongly influenced by the temperature of the gripper belt 1 or of the guide element 3. In the exemplary embodiment, this temperature sensor 7 is located in the uppermost outermost corner of the body 5, which is furthest away from the gripper belt 1.
• the body 5, in which the two temperature sensors 6, 7 are accommodated, consists of a good heat-conducting material, for example aluminum.
• This body 5 is in contact with the guide element 3, which consists of a heat-conducting but wear-resistant material, for example steel. The heat generated by friction between the tape 1 and the guide element 3 is formed, is passed to the temperature sensors 6 and 7.
• the temperature sensors 6, 7 are connected to an evaluation unit 8, which evaluates the temperature difference.
• a display unit 9 is connected to this evaluation unit 8, for example in order to display the temperatures detected by the temperature sensors 6 and 7 and the difference.
• the invention is based on the knowledge that as the gripper belt 1 progressively wears out, i.e. when the gripper belt 1 becomes thinner, the temperature of the gripper belt 1 and / or also of the guide element 3 changes. This is probably due to the fact that the position of the gripper belt 1 changes relative to the guide element 3, so that the friction between the two also changes. In such weaving machines, wear usually has the consequence that the friction between the rapier belt 1 and the guide element 3 increases, so that the heat generated as a result of this friction is also increased. This is used to monitor the wear of the gripper belt by evaluating the temperature as a parameter for the wear of the gripper belt 1.
• a first evaluation possibility consists in determining that the gripper belt 1 is thin and worn overall when the temperature measured by the temperature sensor 6 exceeds a predetermined value. This value is entered into the evaluation unit 8 via an input unit 10.
• the evaluation unit 8 can then, for example, give a signal to a control means 11 which causes the rapier weaving machine to stop when the predetermined value is exceeded.
• the control means can also generate a warning signal, for example switch on a lamp, in order to draw the operator's attention to the fact that the gripper belt 1 is worn and therefore needs to be replaced. see is.
• One or more signals can also be given by the evaluation device 8 directly to an optical or acoustic display 9.
• the wear of the gripper belt is preferably monitored by evaluating the difference between the temperature measured by the temperature sensor 6 and the temperature measured by the temperature sensor 7. For example, it is monitored whether the temperature difference exceeds a predetermined value, which is input to the evaluation unit 8 via an input unit 10. This is advantageous because in this way the environmental influences are excluded, for example an increase in temperature in the weaving room.
• the measured temperature difference is essentially only caused by a higher wear-related friction between gripper belt 1 and guide element 3. This difference is thus a value that is representative of the temperature of the gripper belt 1 and / or the guide element 3, regardless of the ambient temperature.
• the temperature sensor 6 and the temperature sensor 7 are arranged in the same body, they measure different temperatures.
• the temperature that the temperature sensor 6 measures is essentially dependent on the friction between the gripper belt 1 and the guide element 3, since it is arranged in the immediate vicinity of the point at which this frictional heat is generated.
• the temperature sensor 7 is arranged at a point at which the body 5 has already essentially given off the heat to the environment.
• the guide element for the gripper belt 1 is a guide block 12, in which, in accordance with the exemplary embodiment according to FIGS. 1 and 2, the first and second temperature sensors 6, 7 are arranged, which are connected to the evaluation unit 8.
• the temperature sensors it is also possible to arrange the temperature sensors elsewhere, for example on the guide block 13 or on a guide block 14 arranged at a distance from the drive wheel 2.
• the temperature value measured with the temperature sensor 6 and the temperature difference measured by the temperature sensors 6, 7 are relatively high. After a running-in phase for the gripper belt of several hours, the temperature or the temperature difference decreases and an operating value increases. However, the temperature value or the temperature difference increase again with increasing wear of the gripper belt.
• the critical value for the wear of the known gripper belts usually occurs after a period of 10,000 operating hours or more.
• the temperature change or the temperature difference change over time can also be evaluated for monitoring the wear of a gripper belt 1. It is also possible to evaluate this change in temperature or change in temperature difference when switching on a machine that was previously switched off, i.e. how quickly the temperature or the temperature difference increases after switching on the loom.
• each gripper belt it is possible to determine for each gripper belt largely exactly when it needs to be replaced. This allows the gripper belt to continue to be used as long as possible. This is also advantageous compared to the method according to which each gripper belt is replaced on schedule after a certain number of operating hours.
• the invention makes it possible to detect a prematurely worn gripper belt in good time and to prevent the gripper belt from breaking. Likewise, a gripper belt that wears out more slowly than usual can be used longer than for periods specified for a scheduled replacement.
• the invention is not limited to the exemplary embodiments shown only by way of example. In particular, it is possible to measure the temperature or the temperature difference in another way, for example at other points or with other temperature sensors, for example with infrared detectors. The scope of protection is determined only by the claims.

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• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Looms (AREA)
• Radiation Pyrometers (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (1)

Family

ID=3892092

Family Applications (1)

Country Status (4)

Cited By (3)

Families Citing this family (2)

Citations (3)

• 1999
  • 1999-09-16 BE BE9900620A patent/BE1012904A6/nl not_active IP Right Cessation
• 2000
  • 2000-09-12 CN CN00813035A patent/CN1375021A/zh active Pending
  • 2000-09-12 WO PCT/EP2000/008886 patent/WO2001020066A1/de not_active Application Discontinuation
  • 2000-09-12 EP EP00965972A patent/EP1212479A1/de not_active Withdrawn

Patent Citations (3)

Non-Patent Citations (1)

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