Classifications

• • D—TEXTILES; PAPER
  • D03—WEAVING
  • D03C—SHEDDING MECHANISMS; PATTERN CARDS OR CHAINS; PUNCHING OF CARDS; DESIGNING PATTERNS
  • D03C13/00—Shedding mechanisms not otherwise provided for
  • D03C13/02—Shedding mechanisms not otherwise provided for with independent drive motors
  • D03C13/025—Shedding mechanisms not otherwise provided for with independent drive motors with independent frame drives
• • D—TEXTILES; PAPER
  • D03—WEAVING
  • D03C—SHEDDING MECHANISMS; PATTERN CARDS OR CHAINS; PUNCHING OF CARDS; DESIGNING PATTERNS
  • D03C13/00—Shedding mechanisms not otherwise provided for
• • D—TEXTILES; PAPER
  • D03—WEAVING
  • D03C—SHEDDING MECHANISMS; PATTERN CARDS OR CHAINS; PUNCHING OF CARDS; DESIGNING PATTERNS
  • D03C5/00—Cam or other direct-acting shedding mechanisms, i.e. operating heald frames without intervening power-supplying devices
• • D—TEXTILES; PAPER
  • D03—WEAVING
  • D03C—SHEDDING MECHANISMS; PATTERN CARDS OR CHAINS; PUNCHING OF CARDS; DESIGNING PATTERNS
  • D03C5/00—Cam or other direct-acting shedding mechanisms, i.e. operating heald frames without intervening power-supplying devices
  • D03C5/02—Cam or other direct-acting shedding mechanisms, i.e. operating heald frames without intervening power-supplying devices operated by rotating cams
  • D03C5/04—Construction or shape of cams

Definitions

• Thread control device for a textile machine in particular for a color forming device
• the invention relates to a thread control device of a textile machine, in particular for a shedding device according to the preamble of claim 1.
• Thread control devices for textile machines are known in large numbers.
• the closest prior art according to WO 97/08373 discloses a thread control device which is designed with a drive and a retraction device for a thread guide member.
• the thread guide member can be moved in one direction of movement by means of the form-fitting drive and in the opposite direction by means of a force-fitting and pneumatically designed retraction device acting against the form-fitting drive.
• the pneumatic retraction device has a cylinder / piston unit, the cylinder chamber of which is designed with a pressure relief valve and a check valve which is connected to a compressed gas source. The gas pressure in the cylinder chamber is set depending on the operating state of the textile machine.
• the gas pressure is kept lower than in a high-speed phase, so that the electric motor can provide the power required to overcome the load resulting from the compression of the cylinder chamber.
• the electric motor delivers sufficient power so that the gas pressure can be increased further to prevent a roller from lifting off on a cam disk of the positive drive.
• the cylinder chamber can be designed with a manually operable pressure relief valve in order to minimize the resistance created by the compression of the cylinder chamber when the textile machine is being set up.
• a disadvantage of the above solution is that the gas pressure in the cylinder chamber has to be adapted to a particular operating state.
• the valve is therefore designed in such a way that oil separation is also possible in addition to the requirements of stationary operation.
• the valve is actuated at regular time intervals for a few seconds in order to drain the oil that has accumulated in the compression chamber.
• care cycle the speed of the textile machine must be reduced during this process. It is also opened in the creep speed so that the pressure in the cylinder chamber does not rise significantly above the feed pressure. This reduces the power required by the motor, which is necessary so that the main motor can run smoothly at low speeds and so that manual turning on the handwheel is possible without too much effort.
• a disadvantage of the above solution is the great effort for the electrical / pneumatic control of the valve.
• the entire control of the pneumatic drive of the thread control device therefore has a large number of components, such as check valves, pressure relief valves, pressure reducing valves, and electronic control units, which make the system more susceptible to faults.
• the economy of the textile machine is reduced by the repeated lowering of the engine speed every 15 minutes to drain the lubricating oil. Lowering the engine speed can also have a negative impact on the weaving quality, for example, it can lead to a slight change in the width of the fabric being produced.
• the object of the invention is to improve a thread control device of the type mentioned at the beginning.
• the valve has a first valve seat connected to a cylinder chamber and a second valve seat, between which a valve member provided with at least one throttle point and biased with a spring against the first valve seat can be moved, the throttle point being ineffective and the valve member communicating with the compressed gas source blocks, when the valve member is in contact with the second valve seat, the valve can work in different operating states without external control. Furthermore, a reliable oil separation without lowering the speed, a reduction of the maximum compression pressure in the cylinder chamber at partial load, as well as a lowering of the compression pressure to feed pressure in the creeper gear without additional measures is guaranteed by the autonomously working valve.
• the valve housing can fundamentally have different shapes, a cylindrical design of the housing according to claim 4 is advantageous. This design allows the piston-like valve member to be guided well in the housing.
• the piston-like valve member can also be provided with a sealing ring in order to seal the cylinder chamber from the outside.
• the valve can be arranged in a connecting line between the cylinder chamber and the feed pressure chamber.
• a direct arrangement in the cylinder of the cylinder / piston unit is advantageous.
• the valve can thus communicate directly with the cylinder chamber and lubricating oil accumulated in the cylinder chamber can thus be guided through the valve into the feed pressure chamber in a short way. Accordingly, the end part of the valve is directly connected to the feed pressure chamber according to claim 8, in order to minimize the flow resistance and the flow path of the oil flowing away.
• the feed pressure chamber can basically have any configuration.
• An embodiment according to claims 9 to 12 is advantageous, where after the feed pressure chamber is formed with an outlet arranged at its bottom for the oil separation and after which a connection for compressed air can be arranged on a side wall at a distance from the bottom of the feed pressure chamber.
• This arrangement of compressed air connection and oil separation outlet prevents oil that has accumulated in the feed pressure chamber from clogging the compressed air connection or flowing into a connecting line of the compressed air connection.
• each retraction device can have a separate feed pressure chamber.
• valves 13 to 16 A particularly simple embodiment of the valve is described in claims 13 to 16, the valve in connection with claims 5 and 6 being able to be arranged in a lower position of the cylinder chamber of the cylinder / piston unit.
• a lower portion of the cylinder can serve as a housing for the valve.
• the valve chamber can advantageously be delimited by the inner surface of the cylinder, by a closing part which closes off the cylinder chamber and by a valve member and can be connected directly to a compressed gas source via a connection arranged on the cylinder wall.
• a first valve seat for the valve member can be formed on an annular stop.
• a second valve seat can be formed on a sleeve part of the end part. If the valve member moves against the second valve seat, the communication between the cylinder chamber and the compressed gas source is blocked and the throttling points on the valve member become ineffective.
• An embodiment according to claims 17 and 18 is advantageous, according to which the pretensioning force can be adjusted from the outside, for example, by means of a screw.
• the maximum compression pressure of the valve is adjustable by means of the flow cross section of the throttle point according to claim 19. If a higher compression pressure is required, the flow cross-section of the throttle point is reduced. Due to the smaller throttle area, communication between the cylinder chamber and the compressed gas source is interrupted earlier, which means that a higher maximum compression pressure is achieved.
• the switching pressure and the maximum compression pressure in the cylinder chamber can be set in a simple manner by means of the embodiments according to claims 17 to 19.
• FIG. 1 is a side view of a needle ribbon loom
• FIG. 2 shows a shaft device with a pneumatic retraction device in a view transverse to the running direction of the warp threads
• Figure 3 shows the pneumatic retraction device shown in Figure 2 in a cutout and on a larger scale in the basic position
• Figure 4 shows the pneumatic retractor shown in Figure 3 in the compression position
• Figure 5 shows another embodiment of a pneumatic retraction device on a larger scale
• Figure 6 shows the pneumatic retractor shown in Figure 5 in the compression position
• FIG. 7b pressure and piston profiles of the pneumatic retraction device at partial load
• FIG. 7c pressure and piston profiles of the pneumatic retraction device at full load.
• FIG. 1 shows a needle ribbon loom with a machine frame 2, in which a main drive shaft 4 is mounted, which drives at least one weft needle 6, a reed 7, a fabric take-off 8 and a thread control device designed as a shaft device 10.
• the needle ribbon loom has a warp beam frame 12 which carries warp beams 14, of which warp threads 16 are fed to the shaft device 10, which opens the warp threads to a shed 18.
• a thread feed device 20 By means of a thread feed device 20, a weft thread 24 is fed from a thread bobbin 22 to the weft needle 6 and introduces a weft thread loop into the shed 18.
• Successive weft thread loops can be tied with themselves or by means of a catch thread 26, which is fed via a further thread feed device 28 to a knitting needle, not shown here, in order to tie off a registered weft thread loop and to secure it.
• FIG. 2 shows the shaft device 10, in which several shaft frames 30 with thread guide members 31 are each connected by means of a link 32 on the one hand via a positive drive 35 to a cam drive 34 and on the other hand to a pneumatic retraction device 36.
• the cam drive 34 has swivel levers 38 which cooperate with cams 42 of a camshaft 44 at a drive point 40.
• the pivot levers 38 are articulated to the links 32 via joints 48.
• the pivot axes given by the joints 48 run at right angles to the planes spanned by the shaft frame 30.
• the distances A between the pivot levers 38 of the drive points 40 and the respective pivot axes 50 are different between adjacent pivot levers, the distances B between the output points 46 and the fixed pivot axes 50 also being different, the whole in such a way that the shaft frames are of different sizes Lines are displaceable to form a continuously expanding and narrowing shed, as can be seen from FIG. 1.
• the pneumatic retraction device 36 is formed by a cylinder chamber 52 in which a piston 54 is displaceable, which is connected to the link 32 in order to positively compress the piston in the working frequency of the cam drive 34.
• the cylinder chamber 52 is connected to a valve 56.
• the latter is preceded by a feed pressure chamber 58, via which a compressed gas source 60 is connected in order to maintain the gas pressure in the cylinder chamber 52.
• FIG. 3 and Figure 4 show the pneumatic retraction device on a larger scale during a compression process.
• 3 shows the piston 54 at an upper dead center 66 and FIG. 4 the piston 54 at a lower dead center 68 in a cylinder 64 after the compression.
• the valve housing consists of two parts, a sleeve-like housing 70 with a first valve seat formed at one end 72, which is connected to the cylinder chamber 52 and a closing part 74, which has a second valve seat 76 and a through channel 78. The latter is connected to the feed pressure chamber 58.
• a valve member 82 provided with throttling points 80 is movably arranged between the valve seats.
• valve member 82 In the initial state of FIG. 3, the valve member 82 is biased against the first valve seat 72 by means of the biasing force of a spring 84, so that the cylinder chamber 52 and the feed pressure chamber 58 are in communication with one another via the throttle points 80 in the valve member 82 and the through-channel 78 of the end part 74 , At high pressure in the cylinder chamber 52, the valve member 82 moves against the second valve seat 76 and interrupts communication between the cylinder chamber 52 and the feed pressure chamber 58, as shown in FIG. 4. In this position the throttling points 80 are ineffective.
• H stands for the stroke of the piston of the cylinder / piston unit with UT as bottom dead center and T T as top dead center and PK for the pressure of the gas in the cylinder chamber.
• PS represents the switching pressure necessary for the valve member to switch from the first to the second valve seat or from the second to the first valve seat.
• the switching pressure PS can be divided into the feed pressure PD of the compressed gas source and the corresponding pressure PF of the spring force.
• VZ represents the position of the blocked and VO that of the valve communicating with the cylinder chamber via the throttle points.
• the piston 54 moves from top to bottom in the cylinder 64 and, in a first phase, displaces air through the throttle points 80 formed on the piston-like valve member 82 against the feed pressure chamber 58.
• the pressure difference (PK-PD) across the valve member 82 increases until the switching force generated by the cylinder chamber pressure PK on the valve member 82 overcomes the biasing force of the spring 84 and the force generated by the feed pressure PD on the valve member 82, and presses the valve member 82 against the second valve seat 76.
• the throttle point 80 of the valve member 82 is no longer effective.
• the cylinder chamber pressure PK rises sharply during the compression process in the cylinder chamber 52 and reaches its maximum at the bottom dead center UT.
• the valve member 80 moves from the second to the first valve seat 76 as soon as the spring force exceeds the force generated by the pressure difference (PK-PD) on the valve member 80.
• the feed pressure PD is established in the cylinder chamber.
• any oil that may have accumulated in the cylinder chamber 52 can now drain through the passage 78.
• the outflowing oil is blown out by the air displaced into the feed pressure chamber 58 and flows out in an outlet 88 formed on a bottom 86 of the feed pressure chamber for oil separation.
• a connection 90 for compressed air is arranged on a side wall 92 of the feed pressure chamber, and thus prevents the oil from flowing back further.
• FIG. 5 and FIG. 6 show a further embodiment variant of a pneumatic retraction device on a larger scale during a compression process.
• 5 shows the piston 54 again at an upper dead center 66 and
• FIG. 6 shows the piston 54 at a lower dead center 68 in the cylinder 64 after the compression of the cylinder chamber 52 ,
• the wall of the cylinder serves as a valve housing and a valve chamber 94 is delimited by the wall of the cylinder 64, a closing part 74a which closes the cylinder 64 and a piston-like valve member 82a.
• a stop 71 designed as a ring is arranged directly in the interior of the cylinder 64 of the cylinder / piston unit and serves as a first valve seat 72a for the piston-like valve member 82a.
• the latter is in turn biased against the first valve seat 72a by a spring 84a.
• the spring 84a is supported on the end part 74a closing the cylinder, which has an inner sleeve part 96 for guiding the spring 84a and whose free end also serves as a second valve seat 76a for the valve member 82a. If the latter strikes the second valve seat 76a, the throttle point 80a formed in the valve member 82a becomes ineffective.
• a connection 90a arranged on the cylinder for a compressed gas source 60 is blocked by means of the valve member 82a. Oil accumulated in the cylinder chamber 52 can flow out via an outlet 88a for oil separation formed on the end part 74a.
• valve member 82a In the initial state of FIG. 5, the valve member 82a is biased against the first valve seat 72a by means of the biasing force of the spring 84a, so that the cylinder chamber 52 is connected to a compressed gas source via the throttle points 80a Valve member 82a communicate. At high pressure in the cylinder chamber 52, the valve member 82a moves against the second valve seat 76a and interrupts the communication between the cylinder chamber 52 and the compressed gas source 60 by blocking the connection 90a arranged in the cylinder wall, as shown in FIG. In this position, the throttling points 80a are ineffective.
• FIGS. 7a, 7b and 7c show the pressure and piston profiles of the retraction device according to the invention over two load cycles in the creeper gear for a speed of 800 rpm (FIG. 7a), for partial load at 1000 rpm (FIG. 7b) and for full load 4000 U / min (Figure 7c) shown.
• the cylinder chamber pressure PK reaches the required switching pressure PS during a cycle, whereupon the valve blocks the communication of the compressed gas source with the cylinder chamber and the compression in the closed cylinder chamber begins.
• the compression in the cylinder chamber reaches its maximum at a bottom dead center UT.
• the cylinder chamber pressure PK again falls below the switching pressure PS.
• the cylinder chamber is now in connection with the compressed gas source again and when the piston reaches an upper dead center TDC, supply pressure PD is established again in the cylinder chamber.
• the compression pressure in the cylinder chamber prevents the roller from lifting off the eccentric of the positive drive at higher operating speeds.
• the required switching pressure PS is reached earlier ( Figure 7c) than at lower operating speeds.
• the compression therefore takes place over a larger stroke and consequently the maximum compression pressure reaches a higher value than at lower operating speeds.
• the necessary switching pressure PS is again reached, whereupon the valve restores the communication of the cylinder chamber with the compressed gas source.
• the maximum compression pressure is a direct function of the speed of the machine, i.e. the maximum compression pressure increases with higher speed. This is advantageous both for economical operation of the machine and for the correct operation of the positive drive.
• the lubricating oil accumulated in the cylinder chamber flows away continuously. This enables the system to be operated safely and continuously, without any maintenance cycles for removing the lubricating oil from the cylinder chamber.
• the tasks and requirements for the valve described above are autonomous, ie without any external control. Due to the dimensioning of the spring force, the throttle cross-section and the valve autonomous control functions of the valve are given.
• the retraction device for a found control device described here thus autonomously fulfills a wide variety of requirements and at the same time has a minimal technical effort.
• the retraction device is therefore particularly inexpensive to manufacture and its operation is largely maintenance-free and trouble-free due to its simple structure.
• the thread control device according to the invention can also be used for a single thread control, for example for a jacquard machine, furthermore in a weft thread device for feeding individual weft threads.

Landscapes

• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Fluid-Pressure Circuits (AREA)
• Spinning Or Twisting Of Yarns (AREA)
• Looms (AREA)
• Sewing Machines And Sewing (AREA)
• Actuator (AREA)
• Yarns And Mechanical Finishing Of Yarns Or Ropes (AREA)
• Lift Valve (AREA)

Priority Applications (8)

Applications Claiming Priority (2)

Publications (1)

Family

ID=34624412

Family Applications (1)

Country Status (11)

Cited By (1)

Families Citing this family (11)

Citations (2)

Family Cites Families (34)

• 2004
  • 2004-11-05 CN CN2004800345919A patent/CN1886540B/zh active Active
  • 2004-11-05 WO PCT/CH2004/000669 patent/WO2005052233A1/de not_active Application Discontinuation
  • 2004-11-05 US US10/581,004 patent/US20070119142A1/en not_active Abandoned
  • 2004-11-05 AT AT04797226T patent/ATE455885T1/de not_active IP Right Cessation
  • 2004-11-05 JP JP2006540128A patent/JP4617314B2/ja active Active
  • 2004-11-05 ES ES04797226T patent/ES2337470T3/es active Active
  • 2004-11-05 EP EP04797226A patent/EP1687472B1/de active Active
  • 2004-11-05 BR BRPI0416975-1A patent/BRPI0416975B1/pt not_active IP Right Cessation
  • 2004-11-05 KR KR1020067010096A patent/KR100754106B1/ko not_active IP Right Cessation
  • 2004-11-05 DE DE502004010685T patent/DE502004010685D1/de active Active
• 2007
  • 2007-02-21 HK HK07101950.9A patent/HK1094812A1/xx not_active IP Right Cessation

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