Coiling mechanism
The function of the winding mechanism is to lead the woven fabric away from the cloth fell in a timely and quantitative manner according to the fabric’s requirements for weft density, and roll it onto the winding roller, so that the position of the cloth fell will not change due to the introduction of new weft yarns, thereby ensuring Weaving production can be carried out continuously. 1. Classification and process requirements of coiling mechanism 1. Classification According to the nature of leisure, it can be divided into two categories: intermittent type and continuous type. According to the transmission properties, it can be divided into two categories: mechanical type and electronic type. Mechanical intermittent winding mechanism is not adopted by high-speed looms because its intermittent action will cause large impact wear between transmission parts. On high-speed shuttleless looms, mechanical continuous take-up mechanisms are widely used, and now more and more air-jet looms adopt electronic continuous take-up mechanisms. 2. Winding process requirements (1) The winding mechanism should ensure that the formed fabric is led away from the cloth fell at a fixed length on time to obtain a fabric with a specified weft density, and at the same time, the warp released from the weaving beam by the let-off mechanism should be pulled to Within the fabric forming area. (2) The transmission should be accurate and stable to ensure uniform weft density. The weft density adjustment should be quick and easy, and the adjustment range should meet the process requirements. (3) The cloth rolling roller should be light and easy to carry, and the roll should be large to reduce the number of cloth drops; the cloth rolling tension should be uniform, the cloth surface should not have wrinkles, and the cloth rolling roller should be easy to load and unload. (4) Manual operation should be simple and labor-saving. 2. Mechanical take-up mechanism
Figure 2-25 shows the take-up mechanism of the air-jet loom.
The winding mechanism generally consists of several parts such as winding transmission, weft density adjustment, holding and pulling, winding forming, manual operation, and automatic length measurement. 1. Transmission path: yarn supply side crankshaft – synchronous toothed belt – reduction gear box – weft density conversion and reduction gear train – take-up roller and take-up pressure roller – sprocket on the take-up roller – chain – flywheel – plane friction clutch – Friction shaft – cloth roller. 2. Cloth rolling path (Figure 2-26) The fabric first passes through the stretching roller, bypasses the friction roller (winding roller), and then passes through the front pressure roller, lower pressure roller, cloth pressing roller, and is rolled onto the cloth winding roller. The fabric is close to the friction roller under the action of the front pressure roller and the lower pressure roller, and has a large wrapping angle, so that the friction roller has a large grip on the fabric, achieving the purpose of evenly and accurately guiding the fabric away from the cloth mouth, and Meet the requirement of dropping cloth without stopping. The diameter of the large cloth roll of the cloth roll is generally cam or dobby opening: 600mm; crank or common wheel cam opening: 480mm. The diameter of large rolls of cloth also varies between different models. 3. Characteristics of the mechanical take-up mechanism: It has the advantages of continuous leisure, smoothness and accurate calculation of weft density. However, gears must be selected to change the weft density. The weft density changes in steps, making it difficult to meet the precise design weft density requirements. In order to meet the requirements of the designed weft density of the lower machine, it is necessary to go through trial weaving and adjust the tension of the upper machine. Depending on the product, the shrinkage rate can range from 1% to 5%, but the exact value should be obtained after trial weaving. Overview of the winding mechanism of the ZA series air-jet loom: (1) Transmission mechanism: the main component is a reduction gearbox. There are three-stage gear reduction in the box, and its reduction ratio directly affects the weft density. Under the premise that other conditions in the winding part remain unchanged, the larger the reduction ratio, the larger the weft density. Depending on the reduction ratio, the reduction gearbox is divided into three specifications: standard weft density, medium weft density, and high weft density, all of which can be configured on any model of the ZA series loom. The applicable weft density range for high weft density is 40 to 280 picks/inch, the applicable weft density range for medium weft density is 157 to 822 picks/10cm (39.95 to 208.85 picks/inch), and the applicable weft density range for standard weft density is 100 to 525 picks. /10cm (25.51～133.36 latitude/inch). In the positive continuous coiling transmission mechanism, it is particularly necessary to set up a reduction device with a large reduction ratio. Because the length of the fabric rolled by the loom per revolution is the reciprocal of the weft density, the speed is relatively high. Only after being decelerated by the deceleration device can the speed requirements of the take-up roller be met. (2) Holding and traction mechanism: This mechanism is mainly composed of a coiling roller and a coiling pressure roller. The take-up roller and pressure roller cooperate to hold the fabric. The take-up roller rotates slowly driven by the transmission mechanism, and the pressure roller is driven by the take-up roller to rotate due to friction. The size of the traction force holding the fabric is related to the wrapping angle of the fabric to the take-up roller and the surface material of the take-up roller. There are two types of take-up rollers available for the ZA series air-jet loom. One is a take-up roller with a rough rubber surface and a diameter of 166.4mm. The other is a take-up roller with a surface sprayed with stainless steel powder and a diameter of 163mm. . The purpose of coating with rough rubber and spraying stainless steel powder is to increase the friction coefficient of the take-up roller so that the casual linear speeds of the fabric and the take-up roller are basically the same. The diameter of the take-up roller will also affect the weft density. When other conditions remain unchanged, the larger the diameter, the greater the linear speed of the take-up, and the thinner the weft density. (3) Weft density conversion adjustment mechanism: When the weft density needs to be changed when changing the fabric type, the weft density conversion gear is mainly replaced. It is more convenient and economical to change the weft density using this method. Weft density conversion gears include 66 types of conversion wheels and 3 types of standard conversion wheels. Each standard conversion wheel and conversion gear is a set, corresponding to one type of on-machine weft density, so there are 66×3=198 types of on-machine weft density. Before determining the weft density gear, you must first understand the diameter of the take-up roller and the specifications of the reduction gearbox installed on the machine, and then use the actual weft density P w of the fabric to calculate the weft on the machine according to the formula P′ =P w (1-α) Density P′, use P′ value to check the corresponding relationship between weft density and gear in the manualSystem table, select the corresponding weft density gear part number, and then use the machine to test weave to determine whether the selected gear meets the requirements. α in the above formula is the shrinkage rate after unloading. Because the fabric is subject to a certain tension on the loom, the tension decreases after the fabric is unloaded, and the fabric will shrink. Therefore, the actual weft density P w is greater than the weft density P′ w on the machine, which is expressed by α the relationship between the two. α is related to many factors such as the performance of the yarn type used in the fabric, fabric structure, tension on the machine, and moisture regain. It is selected between 1% and 5% according to the specific situation. It is a test data. (4) Winding and forming mechanism: After the woven fabric is led away from the cloth mouth under the action of the holding and pulling mechanism, it is regularly wound on the cloth roller under a certain tension under the action of the winding and forming mechanism. The winding forming mechanism consists of sprockets, flywheels, chains, friction clutches, cloth rolling rollers and cloth roller clamping seats. The diameter of the roll cloth is 100~600mm. During the rolling process, the diameter of the cloth roller gradually increases, and the resistance torque produced on the cloth rolling roller will also increase under the same cloth surface tension. This requires the driving torque to increase as the diameter of the cloth roller increases, thus Ensure that the driving torque can effectively drive the cloth rolling roller to work. When the diameter of the cloth roller increases, the cloth roller detection plate in the mechanism is pushed behind the machine, which increases the positive pressure of the friction clutch, so that the driving torque of the cloth winding roller also increases as the diameter of the cloth roller increases. When the driving torque is greater than the resistance torque, the cloth roller rotates synchronously with the flywheel; otherwise, the clutch slips and the cloth roller rotates slower than the flywheel. This method ensures the process requirement of basically constant cloth tension. (5) Manual operating mechanism: It is used for manual winding or reversal of the winding mechanism during warping or when fabric defects occur. It has a simple structure. (6) Length counting device: mechanical decimal counter with fixed-length automatic stop function. The length of the fabric is automatically calculated based on the weft density of the fabric and the number of beat-ups of the loom. 3. Electronic take-up mechanism The electronic take-up mechanism can be combined with the let-off mechanism to adjust the position of the cloth mouth under the control of a microprocessor to improve fabric quality. Advantages of the electronic take-up mechanism: (1) The fabric weft density only needs to be set directly on the computer or control device keyboard. There is no need to replace the weft density gear. The weft density range is large, which enhances the variety adaptability of the fabric. (2) The weft density can be automatically changed as required during the weaving process. This is an obvious and important feature of the electronic take-up mechanism. This feature enables the loom to produce fabrics with variable weft density. There are three types of electronic coiling mechanisms: stepper motor type, servo motor type and frequency conversion speed regulation type. The schematic diagram of the electronic coiling mechanism is shown in Figure 2-27.
Mechanism overview: (1) Transmission path of the coiling roller: the rotating motor of the coiling motor, the toothed belt and the toothed pulley in the coiling gear box, the worm, the worm gear lamination gear, the lamination shaft, the coiling roller Gear take-up roller The take-up roller rotates at a certain speed to ensure a certain weft density. (2) The path of the cloth is the same as that of mechanical winding. (3) The drive of the cloth roller is the same as that of mechanical winding: the sprocket on the winding shaft turns the roller chain flywheel and the winding tension device gear cloth roller is driven.
AAAERT5Y4375JTY
Extendedreading:https://www.alltextile.cn/product/product-4-124.html
Extendedreading:
Extendedreading:
Extendedreading:
Extendedreading:
Extendedreading:
Extendedreading:
ExtendedReading:
Extendedreading:
Extendedread
