BRPI0416975B1 - WIRE CONTROL DEVICE FOR A TEXTILE MACHINE, ESPECIALLY FOR A SHUTTER DEVICE - Google Patents

Abstract

The invention relates to a thread control device for a textile machine, in particular, for a shedding device, with at least one thread guide body ( 31 ) which may be displaced in one displacement direction by means of a positive drive ( 35 ) and in the opposite direction by means of a non-positive, pneumnatic return device ( 36 ). Me return device ( 36 ) thus comprises a cylinder/piston unit ( 64,54 ), the cylinder chamber of which ( 52 ) is connected to a compressed gas source ( 60 ) by means of a valve ( 56 ). An improvement in control is achieved when the valve ( 56 ) comprises a first valve seat ( 72 ) connected to the cylinder chamber ( 52 ) and a second valve seat ( 76 ), between which a valve body ( 82 ), provided with at least one throttle point ( 80 ), may be displaced, pre-tensioned in the rest position by means of a spring ( 84 ) against the first valve seat ( 72 ), in which the throttle point ( 80 ) is ineffective and the valve body ( 82 ) blocks the communication with the compressed gas source ( 60 ) when the valve body ( 82 ) is in contact with the second valve seat ( 76 ).

Description

DETAILED DESCRIPTION REPORT FOR "YARN CONTROL DEVICE FOR A TEXTILE MACHINE, ESPECIALLY FOR A SHUTTER DEVICE." Technical Field The present invention relates to a yarn control device of a textile machine, especially for a shed forming arrangement according to the preamble of claim 1.

State of the art Thread control devices for textile machines are known in large numbers. The closest state of the art according to WO 97/08373 describes a wire control device which is formed with a drive and a return device for a wire guide member. The wire guide member is then movable in a direction of movement by means of the locking drive due to the shape and in the opposite direction of movement by means of a pneumatic or locking driven kickback device acting for the drive. with locking due to shape. The pneumatic return device features a cylinder / piston assembly, the cylinder chamber of which is equipped with a relief valve and a check valve, which is connected with a compressed gas source. The gas pressure in the cylinder chamber is then adjusted according to the operating state of the textile machine. For example, in a idle phase the gas pressure is lower than in a fast stroke phase so that the electric motor can provide the necessary power to overcome the resulting load by compressing the cylinder chamber. In a fast stroke phase, the electric motor provides sufficient power so that the gas pressure can be further increased to prevent lift of a roller on a locking drive cam disc due to the shape. The cylinder chamber can also be configured with a manually activatable pressure relief valve to minimize the compressive strength of the cylinder chamber when installing the textile machine.

Disadvantageous in the above solution is the fact that the gas pressure in the cylinder chamber must be adapted to a respective operating state. This conditions a costly pressure control device for adjusting the cylinder chamber gas pressure, which requires necessary pressure reducing valves and opening valves to activate each cylinder chamber. In addition, expensive electronic valve control is required to adapt the pressure in the cylinder chambers and their operating state.

For lubrication of the cylinder / piston assembly, for example, oil drips onto the piston and penetrates hydrodynamically into the cylinder chamber despite permanent overpressure therein. Accumulated oil in the cylinder chamber can permanently disrupt the operation of the wire control device as it reduces the air volume in the cylinder chamber to an indeterminate level which, in operation, leads to higher compression pressures in the chamber. -calculable. In the extreme case, where a large part of the cylinder chamber is filled with oil, no further displacement of the cylinder is possible and further operation of the textile machine would lead to considerable damage.

In an improved embodiment of the pneumatic return device described in WO 97/08373, therefore, the valve is so configured that in addition to the requirements of stationary operation, an oil separation is also possible. The valve is then activated at regular time intervals for a few seconds to allow the accumulated oil to drain into the compression housing. In order to prevent lifting of the locking drive cam roll due to the shape, the number of revolutions of the textile machine must be reduced during this operation (so-called "Care Cycle"). At idle speed it is also opened so that the pressure in the cylinder chamber does not essentially increase above the supply pressure. This reduces the required engine power, which is necessary for the main engine to be able to operate round at low engine speeds and thus allow manual rotation on the handwheel without applying too much force.

Disadvantageous in the above solution is the large expense for electrical / pneumatic activation of the valve. All pneumatic actuation control of the wire control device therefore has a large number of components, such as check valves, overpressure valves, pressure reducing valves, as well as electronic control units, which make the system more susceptible. to breakdowns. In addition, the economy of the textile machine is reduced by the recurring 15-minute drop in engine speed for lubricating oil blowing. Falling engine speed may also negatively influence fabric quality, for example, leading to a slight change in the width of the continuous article piece produced.

Disclosure of the Invention It is an object of the invention to improve a wire control device of the type mentioned above. The proposed objective is achieved by the features of claim 1. Due to the fact that the valve has a first valve seat joined with a cylinder chamber and a second valve seat, between which a valve element provided with at least one is movable. a choke point and spring-biased to the first valve seat, the choke point being inactive and the valve element blocks communication with the compressed gas source when the valve element abuts the second valve seat, The valve can work without external activation in various operating states. In addition, reliable oil separation is guaranteed without a reduction in the number of revolutions, a reduction in the maximum compression pressure in the partially loaded cylinder chamber as well as a reduction in the compression pressure for non-metered supply pressure. by the valve operating autonomously.

Advantageous embodiments of the invention are described in claims 2 to 19.

In principle, the various embodiments of the valve configured with two valve seats are conceivable. Advantageous is a configuration according to claims 2 and 3, wherein the housing has two parts, one part having at one end the first valve seat and the other being configured as a terminal part of the housing with the second valve seat. valve and a through channel. The valve therefore has as simple a structure as possible, allowing for low cost production and easy valve assembly. The valve housing may in principle have various shapes, and a cylindrical embodiment of the housing according to claim 4 is advantageous. Such embodiment allows for a good conduction in the housing of the valve element executed in the manner of a piston. The valve element executed in the manner of a piston may furthermore be provided with a sealing ring to seal out the cylinder chamber. In the execution according to claim 4 it is advantageous to execute the choke points as choke openings executed as a valve element. According to claim 5, it is also conceivable to perform the valve element without sealing ring, wherein a gap between the valve element and the housing wall can serve as a choke point. The valve may be arranged in a conduit between the cylinder chamber and the supply pressure chamber. However, a direct arrangement in the cylinder / piston cylinder assembly is advantageous according to claim 6. Further, it is advantageous according to claim 7 to arrange the valve at a point at the lowermost point of the cylinder. The valve can thus communicate directly with the cylinder chamber and the accumulated lubricating oil in the cylinder chamber can then be guided shortly through the valve into the supply pressure chamber. Correspondingly, the valve end portion is directly connected with the supply pressure chamber according to claim 8, to again minimize the creep resistance and the flow path of the flowing oil. The supply pressure chamber may in principle have any desired configuration. Advantageous is a configuration according to claims 9 to 12, wherein the supply pressure chamber may be made with an oil separation outlet disposed at its bottom, and whereby a compressed air connection may be arranged. on a side wall with distance from the bottom of the feed pressure chamber. This arrangement of the compressed air connection and oil separation outlet prevents the accumulated oil in the supply pressure chamber from clogging the compressed air connection or flowing into a connecting duct of the compressed air connection. In principle, each return device may have a separate feed pressure chamber. But according to claim 12, it is advantageous to connect several return devices with a feed pressure chamber. This allows a simple structure with only one compressed air connection and only one oil separation outlet for multiple return devices.

In principle, the most diverse embodiments of the pneumatic return device according to the invention are conceivable. A particularly simple valve configuration is described in claims 13 to 16, wherein the valve may be disposed at a lower point in the cylinder / piston cylinder chamber in connection with claims 5 and 6. According to claim 13, a lower segment The cylinder head can serve as a housing for the valve. The valve housing may advantageously be limited by the inner area of the cylinder, an end portion enclosing the cylinder chamber and a valve member, and be directly connected via a cylinder wall connection with a source of compressed gas. A first valve seat for the valve element may according to claim 14 be made in an annular stop. According to claim 15, a second valve seat may be made in a sleeve portion of the end portion. By moving the valve element to the second valve seat, communication of the cylinder chamber with the compressed gas source is then blocked and the choke points in the valve element become inactive. In addition, it is still especially advantageous according to claim 16 to have an oil separation outlet directly at the end portion. The valve is activated as soon as the pressure in the supply pressure chamber exceeds the switching pressure. The latter depends on both the supply pressure chamber pressure and the spring bending force. An arrangement according to claims 17 and 18 wherein the bending force can be adjusted from the outside for example by means of a screw is advantageous. The maximum compression pressure of the valve is adjustable by means of the throttle flow cross section according to claim 19. If a higher compression pressure is required, then the throttle flow cross section is reduced. Due to the smallest choke area, communication between the cylinder chamber and the compressed gas source is prematurely interrupted, whereby a higher maximum compression pressure is obtained.

By the embodiments according to claims 17 to 19 the switching pressure as well as the maximum compression pressure in the cylinder chamber can be adjusted simply.

BRIEF DESCRIPTION OF THE DRAWINGS Exemplary embodiments of the yarn control device according to the invention will be described in detail below for a needle taping machine using the drawings, which show: Figure 1 - A needle taping machine side view;

Figure 2 is a heald device with pneumatic return device in cross-sectional view of the direction of travel of the warp yarns;

Figure 3 - the pneumatic return device, shown in Figure 2, cut out and enlarged scale in basic position;

Figure 4 - the pneumatic return device shown in Figure 3 in a compressed position;

Figure 5 is another example of a large scale pneumatic return device;

Figure 6 - the pneumatic return device shown in Figure 5 in a compressed position;

Figure 7a - Pressure and piston strokes of the pneumatic return device according to the invention at idle;

Figure 7b - Pressure and piston strokes of the pneumatic return device according to the invention with partial load; and Figure 7c - Pressure and piston strokes of the pneumatic return device according to the invention at full load.

Paths for Carrying Out the Invention Figure 1 shows a needle ribbon weaving machine having a machine frame 2, wherein a central drive shaft 4 is mounted which drives at least one weft needle 6 not shown in more detail, a comb for loom 7, an article 8 outlet and a yarn control device executed as a heald device 10. The needle-taping machine has a warp bar frame 12 carrying warp bars 14, of which warp yarns. warp 16 are fed to the heald device 10, which opens the warp yarns to a loom 18. By means of a yarn addiction device 20, from a yarn bobbin 22 a weft yarn is fed to the weft needle 6, which introduces a weft yarn loop into the loom 18. 18. Subsequent weft yarn loops may be joined by themselves or by means of a capture yarn 26, which is fed by another yarn adduction device. 28 to a needle gill here not shown in greater detail to secure and secure an inserted weft loop. Figure 2 shows the heald device 10, wherein several heald frames 30 with wire guide members 31 are joined respectively by a handlebar 32, on one side, by a locking drive 35 due to the shape, with a cam drive 34 and, on the other hand, with a pneumatic return device 36. The cam drive 34 has pivoting levers 38 which cooperate at a drive point 40 with cams 42 of a cam axis 44. At the movement exit point 46 the pivoting levers 38 are joined by hinges 48 to the handlebars 32.

The pivot axes given by the joints 48 extend at right angles to the planes covered by the heald frames 30. The distances A of the pivot levers 38 of the drive points 40 of the respective pivot axes 50 are different between neighboring pivot levers. that also the distances B from the movement exit points 46 to the fixed pivoting axes 50 are different in total in such a way that the heald frames are displaceable in stretches of different magnitude to form a widening and narrowing loom again continuously as shown in Figure 1. The pneumatic return device 36 is formed by a cylinder chamber 52, in which a piston 54, which is in connection with the handlebar 32, is movable to compress the piston. locking due to the working frequency shape of the cam drive 34. The cylinder chamber 52 is connected with a valve 56. A supply pressure chamber 58 is connected through which a compressed gas source 60 is connected to maintain the gas pressure in the cylinder chamber 52. Figure 3 and Figure 4 show the enlarged scale pneumatic return device during a compression operation. Fig. 3 shows piston 54 at an upper dead end 66 and Fig. 4 shows piston 54 at a lower dead end 68 on a cylinder 64 after compression. The valve housing consists of two parts, a glove type housing 70 with a first valve seat 72 at one end, which is joined with the cylinder chamber 52, and an end portion 74, which has a second valve seat 76 and a passage channel 78. The latter is connected with the supply pressure chamber 58. Between the valve seats is movably disposed a valve element 82 provided with choke points 80.

In the starting state of FIG. 3, the valve member 82 is intended by spring biasing force 84 to the first valve seat 72, so that the cylinder chamber 52 and the supply pressure chamber 58 are in mutually communicating connection via the throttles 80 in the valve member 82 and the through-flow channel 78 of the end portion 74. At high pressure in the cylinder chamber 52, the valve member 82 moves to the second valve seat 76 and interrupts communication between the cylinder chamber 52 and the supply pressure chamber 58 as shown in figure 4. At this position, the choke points 80 are inactive. The compression / expansion operation of the cylinder / plunger assembly is described below based on figures 3 and 4 in connection with the diagrams of figures 7a, 7b and 7c. In the latter, H represents the stroke of the cylinder / piston aggregate piston with UT as bottom dead center and OT as top dead center and PK for gas pressure in the cylinder chamber. PS represents the required switching pressure for the valve element to switch from the first to the second valve seat, respectively from the second to the first valve seat. The switching pressure PS can be divided into the supply pressure PD of the compressed gas source and the corresponding spring force pressure PF. VZ represents the position of the blocked valve and VO that of the valve communicating with the cylinder chamber through the choke points.

Firstly, the piston 54 in cylinder 64 moves from top to bottom and then moves, in a first phase, through the throttle points 80 made in the piston-type valve element 82 to the supply pressure chamber 58. increasing piston increases the pressure difference (PK-PD) above the valve member 82 until the switching shape produced by the pressure of the cylinder chamber PK on the valve member 82 overcomes the spring bending force 84 and the shape produced by the supply pressure PD on the valve member 82, and press the valve member 82 to the second valve seat 76. The throttling point 80 of the valve member 82 is then no longer active. By further displacing the piston 54 to valve 56, the pressure of the cylinder chamber PK therefore increases during the compression operation in the cylinder chamber 52 and thus reaches its maximum in the lower dead center UT. In the expansion phase, the valve element 80 moves from the second to the first valve seat 76 as soon as the spring force exceeds the force produced by the pressure difference (PK-PD) in the valve element 80. At the end of the expansion phase, which corresponds to the upper dead center 66 of the piston, the supply pressure PD is established in the cylinder chamber. In addition, the oil accumulated in the cylinder chamber 52 can then flow through the passage channel 78. With a next compression operation, the flowing oil is blown out by the air displaced into the supply pressure chamber 58 and flows in. an outlet 88 executed in a bottom 86 of the oil pressure feed pressure chamber. A compressed air fitting 90 is disposed in a side wall 92 of the supply pressure chamber and thus prevents further oil reflux.

Figures 5 and 6 show another embodiment of a larger scale pneumatic return device during a compression operation. Fig. 5 then shows plunger 54 again at an upper dead center 66 and Fig. 6 plunger 54 at a lower dead center 68 on cylinder 64 after compression of cylinder chamber 52. A valve 56a is again disposed directly at a central point. to the lower end of cylinder 64. The cylinder wall then serves as a valve housing and a valve housing 94 is limited by cylinder wall 64, an end portion 74a enclosing cylinder 64 and a piston-like valve member 82a. A ring stop 71 is directly disposed within cylinder 64 of the cylinder / piston assembly and serves as a first valve seat 72a for the piston type valve member 82a. The latter is in turn protected with a spring 84a for the first valve seat 72a. Spring 84a then abuts end portion 74a enclosing the cylinder, which has an inner sleeve guiding portion 96 of spring 84a and whose free end further serves as a second valve seat 76a for valve member 82a. By bumping the latter into the second valve seat 76a, the throttling point 80a executed in the valve element 82a becomes inactive. Also in this position a connection 90a disposed in the cylinder to a compressed gas source 60 by means of the valve element 82a is blocked. Through an oil separation outlet 88a, carried out at the end portion 74a, accumulated oil in the cylinder chamber 52 can flow.

In the starting state of Fig. 5, valve member 82a is biased by spring bending force 84a to first valve seat 72a so that cylinder chamber 52 is in communication with a compressed gas source through choke points 80a on valve member 82a. At high pressure in cylinder chamber 52, valve member 82a moves to second valve seat 76a and interrupts communication between cylinder chamber 52 and compressed gas source 60 by blocking port 90a disposed in the cylinder wall , as shown in Figure 6. At this position, choke points 80a are inactive.

At the end of the expansion phase, supply pressure is established in the cylinder chamber 52. The accumulated oil in the cylinder chamber 52 can then flow through the throttle points 80a to the valve housing 94. With the next operation of Upon compression, the flowing oil is blown by the air displaced into the valve housing 94 and flows into the outlet 88a made in a bottom 98 of the end portion 74a for oil separation. The compressed air fitting 90a is disposed in a cylinder wall 100 spaced from the bottom of the end portion and thus prevents further oil reflux.

Figures 7a, 7b and 7c show pressure and plunger curves of the return device according to the invention for two idle load cycles at a speed of 800 rpm (Figure 7a) for partial load at 1000 rpm (figure 7b) and for full load at 4000 rpm (figure 7c).

At idle speed up to an operating speed of eg 800 rpm (figure 7a), through the valve element choke points, continuous pressure compensation occurs, so that the cylinder pressure PK does not reach the required switching pressure PS to communication interruption between the cylinder chamber and the compressed gas source. The pressure in the cylinder chamber PK is therefore always of the order of high supply pressure PD. The load to the motor resulting from the pneumatic drive is therefore small and enables a smooth stroke of the engine and, especially with the drive off, a movement of the hand held wire control device, for example for adjustment and repair purposes.

At a partial load of 1000 rpm (Figure 7b), the pressure in the PK cylinder chamber reaches the required PS switching pressure during a circus, after which the valve blocks communication of the compressed gas source with the cylinder chamber and begins to flow. compression in the closed cylinder chamber. Compression in the cylinder chamber reaches its maximum at a lower dead center UT. With subsequent expansion, the pressure in the PK cylinder chamber falls again below the PS switching pressure. The cylinder chamber is then again in communication with the compressed gas source and, when a top dead end of the piston is reached, the PD supply pressure is again set in the cylinder chamber. Compression pressure in the cylinder chamber prevents the lifting of the locking drive eccentric roller due to the higher operating speed design.

At full load of 4000 rpm, the required PS switching pressure is reached earlier (figure 7c) than at lower operating speeds. Compression therefore takes place over a longer stroke and therefore the maximum compression pressure reaches a higher value than at lower operating speeds. With the subsequent expansion, the required switching pressure PS is reached again, after which the valve restores communication of the cylinder chamber with the compressed gas source. The maximum compression pressure is a direct function of machine speed, ie with higher speed also increases the maximum compression pressure. This is beneficial for both economical machine operation and perfect operation of the locking drive due to its shape.

Claims (19)

1. Yarn control device for a textile machine, especially for a shed forming device, with at least one yarn guide member (31) which is movable in the direction of movement by a drive (35) executed locking due to the shape and the opposite direction of movement by means of a pneumatically operated lifting device (36) and locking due to the force, the latter having a cylinder / piston assembly (64, 54) whose cylinder (52) is joined by a valve (56, 56a) with a compressed gas source (60), characterized in that the valve (56, 56a) has a first valve seat (72, 72a) joined with the cylinder chamber (52) and a second valve seat (76, 76a), between which a valve element (82, 82a) is provided with at least one throttle (80, 80a), which is protected by middle of a spring (84, 84a) to the first valve seat (72, 72a), without the throttling point (80, 80a) is inactive and the valve member (82, 82a) blocks communication with the compressed gas source (60) when the valve member (82, 82a) abuts the second valve seat. valve (76, 76a). Wire control device according to claim 1, characterized in that the valve has a housing (70) at one end of which the first valve seat (72) is provided. Wire control device according to claim 2, characterized in that the second valve seat (76) is made of an end portion (74) made of a through channel (78). Wire control device according to claim 2 or 3, characterized in that the housing (70) is made cylindrical, in which the valve element (82) executed in the piston manner is guided sealed against the wall. from the box. Wire control device according to claim 2 or 3, characterized in that a gap between the valve element (82) and the valve housing wall (56) serves as a choke point. Wire control device according to one of Claims 1 to 5, characterized in that the valve (56, 56a) is arranged in the cylinder chamber (52). Wire control device according to one of Claims 1 to 6, characterized in that the valve (56, 56a) is arranged at the lowest point of the cylinder (64). Wire control device according to one of Claims 1 to 7, characterized in that the end portion (74) of the valve (56) is directly connected with a supply pressure chamber (58). Wire control device according to claim 8, characterized in that the supply pressure chamber (58) has an oil separation outlet (88) for an oil from the cylinder chamber (52). Wire control device according to claim 9, characterized in that the outlet (88) for the oil separation is arranged on a bottom (86) of the supply pressure chamber (58). Wire control device according to claim 10, characterized in that a connection (90) for compressed air is disposed in a side wall (92) of the supply pressure chamber (58) spaced from the bottom ( 86) of the supply pressure chamber. Wire control device according to one of Claims 8 to 11, characterized in that the supply pressure chamber (58) of at least one of the return devices (36) serves as the supply pressure device and oil drainage. Wire control device according to claim 1, characterized in that a lower segment of the cylinder (64) serves as a valve housing and has a connection (90a) for the compressed gas source (60). Wire control device according to claim 13, characterized in that an annular stop (71) is disposed within the cylinder (64) and it is formed as the first valve seat (72a) joined with the chamber. of cylinder (52). Wire control device according to claim 14, characterized in that the cylinder (64) is closed by means of the end portion (74a), the latter having a sleeve portion (96) whose end The free valve serves as a second valve seat (76a). Wire control device according to claim 15, characterized in that an outlet (88a) is arranged for oil separation at the end portion (74a). Wire control device according to claim 1, characterized in that the switching pressure (PS) of the valve (56, 56a) is adjustable by varying the spring biasing force (84, 84a). Wire control device according to claim 17, characterized in that the spring biasing force (84, 84a) is adjustable from the outside. Wire control device according to claim 1, characterized in that the maximum compression pressure (PK) of the cylinder chamber (52) is adjustable by means of the flow cross-section of the choke point (80, 80a).