RU2602616C2 - Device for adjusting tension of thread-like material - Google Patents

Abstract

FIELD: textile and paper.

SUBSTANCE: invention relates to adjust tension of thread-like materials and can be used in textile industry and for equipment for rewinding flexible materials. Device to adjust tension of the filamentous material comprises thread braking assembly, thread tension transducer unit and thread leading eyelets. Thread braking assembly is made in the form of magnet actuated system on an elastic suspension. Suspension comprises magnetic cores, magnet and an inductance coil, coaxially arranged there braking part. Braking part comprises a flexible brake plate to interact with thread and fixed brake plate connected with membranes and inductance coil. Thread tension transducer unit is made with a strain transducer. Strain transducer consists of elastic element with resistance strain gauges attached.

EFFECT: higher efficiency and reliability of tension of thread and accuracy of thread tensioning device.

3 cl, 4 dwg

Description

Technical field

The invention relates to devices for controlling the tension of filamentary materials and can be used in machines of the textile industry and for equipment for rewinding flexible materials, such as wire, tape, etc.

State of the art

One of the necessary conditions for obtaining products from long filamentary materials with the required technical characteristics is to ensure the filamentary material is fed into the working area with a given tension.

In particular, in the weaving industry, when forming the fabric on the weaving machine during the feeding and laying of the weft yarn, it is necessary to maintain a predetermined constant tension of the yarn at each yarn from the throat to the throat. From a technological point of view, stabilization of the constant tension of the weft threads in the fabric allows you to get a uniform weave structure of the weft and warp threads, eliminate defects in the formation of the left and right edges, and also has a positive effect on the uniform load, work time and elongation of the weft thread.

Maintaining a given thread tension is carried out using a thread-like tension regulator. The design of the thread tensioner must meet the following basic conditions:

the constancy of the tension of the thread, the possibility of its regulation;

easy passage of thread irregularities;

quick reaction to thread irregularity or breakage.

In practice, the use of tensioners of two types is known: mechanical and mechanical with electromagnetic control.

Mechanical thread tensioners have a simple design, most often of a disk type, which are configured for a constant braking force created by the force of the spring acting on the movable clamping part (usually in the form of a clamping disc) and through it on the thread, pressing it to the lower stationary part ( lower drive). However, this technical principle of the thread tensioner does not provide reliable maintenance of a constant tension of the filamentary material and does not respond to changes in the conditions of passage and condition of the thread, especially for threads with great unevenness in length. In addition, when working with textile thread, if a nodule or similar defect occurs, the thread may shift to the periphery of the disk and be out of the thread tensioner. The latter problem can, in particular, be solved by the design of a thread tensioner with rotating discs, as proposed, for example, in Chinese patent application CN 103950794 A, publ. 07/30/2014 [1].

The efficiency of the thread tensioner is increased on the basis of designs with an active tension control system that regulate the clamping force of the threadlike material, taking into account the conditions of passage in the zone of creation of the clamping force. This is ensured by structures whose work is based on the electromagnetic control principle.

In known devices of thread tensioners, with electromagnetic control the magnitude of the clamping force of a moving thread passing between the brake elements (see, for example, US Pat. US 6,224,009 (B1), publ. 05/05/2001 [2]), the clamping force of the movable part of the thread tensioner varies in depending on the output tension of the thread. For this, the sensitive element with which the filamentary material interacts is fixed on a movable core-rod carrying a permanent magnet, covered by a coil electrically connected through an analog converter with a microprocessor-based control unit, which in turn is connected to a rod position sensor. A change in the position of the rod under the action of a changing thread tension is detected by the rod position sensor, generates a signal supplied to the microcontroller, which compares it with the signal from the electromagnet coil and, accordingly, changes the position of the rod, gives a signal to change the magnitude of the current flowing through the coil, creating a magnetic field strength, causing a change in the force of pressing the thread to the fixed element of the braking part of the thread tensioner.

However, in the solution [2], the combination of a sensing element and an actuator controlled by magnetic field forces in one movable unit of the load absorbing the filament, reduces the accuracy and speed of regulation to maintain a given tension, which reduces the benefits of active control and regulation.

In a known solution according to US Pat. US Pat. No. 6,095,449, publ. 08/01/2000 [3], control of the tension of filamentary material and regulation of the tension of the thread is carried out by separate units: the node of the sensor of the thread tension and the braking unit of the thread with a planar braking element of the braking part and electromagnetic thread clamping means associated with the thread tension control unit. In this design, the thread passes through three guide eyes, between which the zone of the braking part and the zone of the sensing element in which the thread tension is controlled are sequentially determined.

In this solution, the thread in the zone of the sensing element is constantly loaded with elastic force from the sensing element of the tension sensor assembly with an inductive circuit for generating a mismatch signal corresponding to the measured thread tension and supplied to the control unit, where a comparison is made with the set value of the tension value. Such a solution for the tension sensor unit is characterized by insufficient reliability due to a possible violation under the influence of external factors of constant contact of the thread with the sensitive element. Due to transients that occur in the thread tension sensor circuit, the system as a whole works with some delay, which affects the speed of the device. In addition, the use of a braking element in the form of a planar element creates conditions for the accumulation of textile dust in the braking zone of the thread, which reduces the reliability and accuracy of the device.

A similar solution is also used in the device for regulating the tension of the thread according to German patent application DE 102012005478, publ. 09/19/2013 [4], which is adopted as a prototype comprising a thread tension unit with a braking part and a thread tension sensor assembly associated with a control unit for maintaining a predetermined thread tension, guide eyes for a moving thread, two of which are stationary, and the third is movable mechanically connected with the node of the thread tension sensor. The thread tension unit is made with an electromagnetic actuating means for controlling the braking part of the plate type. The device for the technical solution [4] has the same disadvantages as the device for the technical solution [3].

Disclosure of invention

The technical task and the technical result of the present invention is to increase the speed and reliability of the device, the thread tension and the accuracy of the device.

To achieve the indicated technical result, there is provided a device for controlling the tension of filamentary material containing a braking unit for the thread, a node for the thread tension sensor connected to the control unit, and thread conducting eyes, in which the braking unit for the thread is made in the form of a magnetically moving system on an elastic suspension containing magnetic circuits, a magnet and an inductance coil, coaxially with which a braking part is installed with a flexible brake plate for interaction with a thread and a stationary brake plate, connected by means of a connecting supporting element with membranes and an inductor, and the node of the thread tension sensor is made with a strain gauge consisting of an elastic element with glued strain gauges and a wire-conducting eye fixed to the elastic element.

Preferably, the brake part consists of a base with grooves and side cheeks and a flexible brake plate, which is hooked into said base grooves, so that the deformation of the flexible brake plate in the direction of thread movement is limited by said side cheeks forming the profile of the flexible convex brake plate.

Preferably, the thread braking unit is rotatably mounted relative to the thread tension sensor assembly to provide unimpeded threading.

Brief Description of the Drawings

In the drawings, the same elements are denoted by the same reference numerals.

FIG. 1 is a general view of a device for tensioning filamentary material.

FIG. 2 is a cross-sectional view of a filament tensioner in FIG. 1 along line AA with a rotation of 90 °.

FIG. 3 - design of the clamping element.

FIG. 4 is a schematic diagram of controlling the tension of a filamentary material.

Description of the invention

The device for adjusting the tension of the filamentary material of the present invention and its operation are explained with reference to textile yarns for devices for laying the weft yarn by mechanical means for introducing the weft yarn into the throat, for example, on weaving machines with microplayers.

In FIG. 1 shows a general view of a device for tensioning filamentary material, and in FIG. 2 - section of the device along the line AA rotated 90 °.

The device 1 for tensioning the thread contains two functional units: node 2 braking threads with a movable magnetic system and node 3 of the sensor thread tension with strain transducer. The housing 14 (see Fig. 1 and 2) of the magnetic movable system by means of a finger 5, mounted in a ferrule 4, connected by a coupling nut 6 with the housing of the magnetic system, is connected with the housing 7 of the thread tension sensor assembly. The finger 5 with a thread determines the distance between the housing 14 of the movable magnetic system and the housing 7 of the strain transducer. The finger 5 also by means of a magnet 8, mounted on the housing 7, will form a magnetic latch, which ensures, by means of a lock nut 9 and a screw 10, the holder 4 of the housing of the magnetic mobile system relative to the housing 7 of the strain gauge. In FIG. 1 also shows a cracker 11 having an axis 12 and a fork 13.

The braking unit 2 of the thread with a magnetic movable system (see Fig. 2) includes a housing 14, in the inner cavity of which membranes 15 and 16 are installed, separated by bushings 17 and 18, placed along the axis "O" of the membranes, in the central hole of which is installed a connecting bearing element made in the form of a screw 19. An inductor 20 is fixed at the top of the screw 19, at its head, and a sleeve 21 and a braking part 22 are fixed on the bottom of the screw, which will be described later.

The membranes 15 and 16 are fixed in the housing 14 through the gasket 23 with screws (not shown). The contacts (not shown) of the coil 20 are connected by a flexible wire to a connector (not shown) located on the flange 24. A magnetic circuit consisting of magnetic circuits 25 and 26 and magnet 27, which is closed by a cover 28, is fastened through the flange 24 from the contact side.

A groove 29 is made on the outer surface of the housing 14, which serves as a guide for the screws 10 installed in the coupling nut 6, which allows the coupling nut to rotate and fix in the desired position. By means of a thread made on the inner surface of the coupling nut 6, the latter is connected to a ferrule 4 in which a threaded pin 5 is installed (see Fig. 1), which determines the distance between the housing 14 of the movable magnetic system and the housing 7 of the strain gauge. The lock nut 9, which serves to fix the holder, moves along this thread. The rotation and fixing of the coupling nut 6 in the required position is provided by the screws 10. On the holder 4 are also a cracker 11 having an axis 12 around which the fork 13 is pressed into the housing 7. Moreover, as already mentioned, fixing the holder 4 in the working position relative to the housing 7 is carried out using a magnetic latch, consisting of a finger 5 and a magnet 8, mounted on the housing 7.

The braking part 22 shown in FIG. 3, consists of a base 30 and a flexible brake plate 31. The base 30 has two grooves 32 and 33 and two side cheeks 34 and 35 of a special shape that are installed at certain angles to the base 30. The flexible brake plate 31 has plate hooks 36 and 37. B grooves 32 and 33 of the base freely enter the plate hooks 36 and 37 of the flexible brake plate 31. Due to the non-rigid attachment of the hooks at the base, it is possible to change the shape of the flexible convex brake plate and, accordingly, the braking force over a wide range by moving the base 30 along the "O" tikalnoy axis. This allows you to control the tension in a wider range of linear densities of moving threads and reduce breakage of the threads by stabilizing their tension. In this case, the convex shape of the brake plate significantly reduces the occurrence of conditions of accumulation of textile dust in the zone of pressing the thread to the fixed plate.

The node 3 of the thread tension sensor with a strain gauge includes a housing 7 with a strain gauge 39, mounted in a glass 38 with screws. The strain gauge 39 consists of an elastic element 40 and strain gages 41 glued to it. The elastic element of the strain transducer has a thread-conducting eye 42, and two fixed thread-conducting eyes 43 and 44 are fixed to the housing 7 through which the moving thread passes. On the body 7, opposite the flexible brake plate 31 of the braking part 22, a brake plate 45 made of glass is fixed.

The contacts of the strain gauge are connected to the connector 46 (see Fig. 1) installed in the glass 38.

To ensure unimpeded threading of the thread, the braking unit 2 of the thread is rotatably mounted relative to the node 3 of the thread tension sensor. For this purpose, a cracker 11 is installed on the clip 4, having an axis 12, around which the fork 13 is pressed, pressed into the housing 7. In this case, the fixing of the clip 4 in the working assembled position of the device relative to the housing 7 is carried out using a magnetic latch consisting of a finger 5 and a magnet 8 mounted on the housing 7.

In FIG. 4 is a schematic diagram of a thread tension control applied to a weaving machine with a mechanical weft spacer, which shows the mechanical part and the electrical part of the thread tension control system. The mechanical part includes the fixed conductive eyes 43, 44, the conductive eye 42 of the heat transducer 39 of the thread tension sensor assembly 3, an elastic suspension (UP) with the braking part 22 of the thread braking assembly 2 and the brake plate 45. The electrical part includes a strain gauge 41 of the assembly 3 the tension of the thread, a control unit 47 based on a microcontroller with an analog-to-digital converter (ADC) of the strain gauge and the inductance coil 20 of the thread braking unit 2.

The control unit regulates the tension in accordance with a given sequence diagram of its operation. In the first phase, a fixed current is established that provides the necessary clamping force, in the second phase, when this current is applied, the thread tension is controlled according to the strain gauge readings, in the third phase - free run - the control unit supplies a negative polarity current to the active actuator (inductor 20).

The weft thread 49, wound from the bobbin 48, passes through the eye of the balloon 50, enters the input thread-conducting eye 43 of the thread tension device. Passing between the braking part 22 and the stationary brake plate 45, the weft thread is guided to the conductive eye 42 of the tension sensor assembly 3. Next, the weft thread enters the output thread-conducting eye 44, the compensator eye 51, the guide eye 52 and is clamped by the sponges of the spring of the weft yarn 53.

The weft tension device on the weaving machine is installed on the weft dressing line. The initial braking force is set in two stages. First, manually set a gap equal to the diameter of the moving thread between the stationary brake plate 45, mounted on the housing 7 of the node 3 of the thread tension sensor, and a movable flexible brake plate 31 of the braking part 22 of the node 2 braking thread. This is achieved by turning the coupling nut 6, followed by the displacement of the base 30 along the vertical axis “O” of the device. This moves the coil 20, the bushings 17, 18, the sleeve 21 and the base 30 of the braking part 22 down until the flexible brake plate 31 touches the surface of the thread.

Then, using a potentiometer contained in the control unit 47, voltage is supplied to the coil 20, which, acting on the base 30 of the brake part 22, presses the thread against the stationary brake plate 45 of the housing 7. As a result, when the thread moves, tension arises in it, the value of which is measured in cH, is displayed on the indicator and is supported by electrical connection of the thread tension sensor unit with the braking unit 2, depending on the magnitude of the signal supplied from the strain gauge 39 to the inductor 20.

With a similar installation of the brake plates 45 and 31, the voltage supplied to the coil 20 has a minimum value, which contributes to less heating of the coil and increases the reliability of the entire device.

To stabilize the braking force, which depends on the shape of the flexible brake plate 31, the flexible brake plate 31 is made of heat-treated tape and mounted between the two side cheeks 34 and 35 of the base 30. Fastening the flexible brake plate 31 is carried out using the hooks 36 and 37, available at the ends the plate 31. The deformed plate 31 with hooks enters the grooves 32 and 33 of the base 30 and due to elastic forces is pressed against the side cheeks 34 and 35, which form, due to their profile, a circle or semi-ellipse shape, which reduces the formation of the flexible brake plate 31 from exposure to a moving thread of particularly high linear density. The attached mounting device of the flexible brake plate 31 in the base 30 makes it easier and faster to change the flexible brake plate 31 during maintenance.

The thread tension device operates as follows.

The component of the tension force of the weft thread 49 is converted into a vertical movement of the thread-conducting eye 42 and deformation of the thread section with the strain gauge 41 of the strain gauge 39. The signal from the strain gauge is transmitted through the instrument amplifier (DUT) to the ADC of the microcontroller of the control unit. According to the testimony of the strain gauge, tension control is carried out in accordance with the software of the microcontroller. The control signal of the microcontroller is supplied to the inductor 20. The electric current flowing in the inductor 20 creates a magnetic flux that interacts with the magnetic flux formed by parts 25 and 26 of the magnetic circuit and a permanent magnet 27. This interaction of magnetic fluxes causes an electrodynamic force that causes the coil 20 to move, and with them the connecting the supporting element 19. Thus, when the tension value of the weft thread 49 changes, the clamping force of this thread between the flexible plate 31 of the braking part 22 resiliently suspended by means of brane 15 and 16, and a fixed plate 45. The tension setting by changing the initial clamp current and calibrating the strain gauges is processed by the microcontroller program.

The device of the thread tension in the proposed design provides a constant supply of thread to the processing zone by ensuring:

- automatically reduce the magnitude of the tension of the threads that go beyond the technologically necessary;

- reducing the amplitude of fluctuations in the magnitude of the tension with a minimum control error;

- suitability for all types and linear densities of threads;

- convenience and ease of maintenance with the ability to adjust tension during operation of the equipment.

Claims (3)

1. A device for regulating the tension of filamentary material containing a node (2) for braking the threads, a node (3) for the sensor for tensioning the threads associated with the control unit, and thread-conducting eyes, in which the node (2) for braking the threads is made in the form of a magnetically mobile system on an elastic suspension, containing magnetic circuits (25, 26), a magnet (27) and an inductor (20), coaxially with which the braking part (22) is installed with a flexible brake plate (31) for interacting with the thread and the stationary brake plate (45), connected by a connecting carrier element (19) with membranes (15, 16) and an inductor (20),
moreover, the node (3) of the thread tension sensor is made with a strain gauge (39), consisting of an elastic element (40) with glued strain gauges (41) and a thread-conducting eye (42) fixed to the elastic element. 2. The device according to claim 1, characterized in that the brake part (22) consists of a base (30) with grooves (32, 33) and side cheeks (34, 35) and a flexible brake plate (31), which has its hooks ( 36, 37) is installed in the mentioned grooves of the base, so that the deformation of the flexible brake plate in the direction of movement of the thread is limited to the said side cheeks, forming the profile of a flexible convex brake plate. 3. The device according to claim 1, characterized in that the thread braking unit (2) is mounted rotatably relative to the thread tension sensor assembly (3) to ensure unimpeded threading.

Images