JPS6054838A - Stepless change gear of peripheral speed of roll in longitudinal stretching machine - Google Patents

Abstract

PURPOSE:To easily and highly accurately change the peripheral speed of the roll of a stretching machine in a short time by a method wherein the rotation on the output side of a stepless transmission provided in a driving system for stepless speed change is given to the center shaft of a cam in a differential gear mechanism. CONSTITUTION:A power transmission gear 22 and a pulley 23 are attached on a roll, which acts as a peripheral speed reference. The gear 22 is connected to an idle gear 24, the spline S of a differential gear mechanism 25, a gear 26 fixed onto the spline S, a spline 27, the pitch of which is the same as that of said spline S and the number of teeth of which is different from that of said spline S, a spline D, the pitch and number of teeth of which are respectively the same as those of said spline S, a gear 26A and a gear 28. The pulley 23 is connected through timing belts 32 and 38 to the output shaft 33 of a stepless transmission 29 and to the center shaft 35 of a cam 34 in the differential gear mechanism 25. Because the rotation on the output side of the stepless transmission 29 is transmitted under the condition that the speed of the rotation is changed to the center shaft 35 in a driving system for power transmission, the speed of the spline D is changed, resulting in changing the speed of a roll 15 continuously.

Description

DETAILED DESCRIPTION OF THE INVENTION [1] Technical Field The present invention relates to an apparatus for steplessly changing the circumferential speed of a roll for longitudinally stretching a plastic film.

[2] Conventional longitudinal stretching machines for glass film use multiple orifices to perform preheating, stretching, and heat setting to remove internal strain and stabilize the product form. The longitudinal stretching of the film is performed by preheating the surface of a plurality of heated preheating rolls, and increasing the circumferential speed of the heatsetting roll between the preheating rolls and the heat setting roll to stretch the film. Longitudinal stretching is carried out by stretching the film in the running direction, but on these preheating rolls, the film is sequentially elongated due to thermal expansion and tension in a softened state, and gradually becomes slack on the rolls. In order to prevent this slack, reduce slippage on the rolls, and provide stable stretching, each preheating roll is set to a predetermined speed minus (deceleration) until the next roll (roll in the film running direction). Therefore, conventionally, the drive system for each roll was created by calculating the peripheral speed ratio of the rolls in advance depending on the material of the film to be processed at the design stage, and the peripheral speed of the rolls was constant. Therefore, when operating conditions or monthly film charges change, the desired roll peripheral speed ratio can be obtained by changing the diameter of the belt drive pulley provided at the final stage of the drive system for each roll. This change was made through trial and error based on experience and intuition, resulting in a great deal of wasted effort and expense.In addition, in the case of new A-3 films that will appear in the future, even more effort and expense will be required. is necessary.

[3] Purpose of the Invention The present invention eliminates the above-mentioned drawbacks, and allows changes in roll circumferential speed to be made more quickly and easily when it is necessary to change the roll circumferential speed due to changes in the drawing ratio and operating conditions due to new materials in the future. Moreover, it is an object of the present invention to provide a continuously variable roll circumferential speed transmission device for a longitudinal stretching machine that enables highly accurate speed changes.

[4] Summary of the invention In a longitudinal stretching machine for plastic film, based on a roll that serves as a peripheral speed reference before or after one of the rolls to be driven, the roll to be driven and the roll that serves as the peripheral speed reference are determined. In the power transmission drive system installed in between, there are two cylinders for input and output, each having spline-shaped teeth with different numbers of teeth on the inner circumference of the cylinder.
Individual Do-I Tsumugi・Place them side by side on top, and press the [ of these two cylinders]
1], insert an elastic ring on the outer periphery with teeth having the same pitch and the same number of teeth as the smaller number of teeth among the two cylinders, and Furthermore, an elliptical cam is provided inside via a ball bearing, and the elastic ring is bent into an elliptical shape by the elliptical cam via the ball bearing, and the long axis connects the inner teeth of the input/output cylinder to the The external teeth of the elastic ring mesh with each other, and due to the total power transmission, the difference in the number of teeth, the input/output direction of the cylinder, and the rotation direction of the cam, the difference between the cylinder with a different number of teeth and the elastic ring. A differential gear mechanism is provided that increases/decelerates the output (IIIO) of the cylinder by varying the relative speed, and, apart from the power transmission drive system, a differential gear mechanism is provided between the roll serving as the circumferential speed reference and the differential gear mechanism. A continuously variable transmission drive system is provided, a continuously variable transmission is incorporated into the continuously variable transmission drive system, and rotation on the output side of the continuously variable transmission is applied to the oval cam of the differential gear mechanism at a variable speed. This is a continuously variable transmission device for a longitudinal stretching machine for plastic film, in which the rotation speed of the output side of the cylinder of the differential gear mechanism is changed, and the rotation speed of the roll to be driven can be changed steplessly.

[5] Embodiment An embodiment of the present invention will be explained with reference to the drawings. FIG. 1 is a front view of a longitudinal stretching machine in which rolls 11 and 20 are arranged in a staggered arrangement, and all the rolls are heated by a heat medium. There is. The rolls 11 to 16 are preheating rolls, and the rolls 17 to 20 are heat setting rolls after stretching. The longitudinal stretching of the film is mainly performed between rolls 16 and 17. The preheating rolls from Roll II to Roll 161 steplessly move up to 5 inches between each roll from Roll 15 to Roll 11 based on the circumferential speed of the roll holder; There is.

Further, the heat set rolls of the roll 17 and the color roll 204 have the ability to steplessly increase the speed of rolls 18 to 20 simultaneously by a maximum of 5 inches based on the circumferential speed of the roll 17. To explain the continuously variable transmission device on the preheating roll side as follows, there are 16 rolls that serve as a reference for 5 circumferential speeds, and one end of the shaft of this roll 1 is connected to a drive source 21 as shown in FIG. At the other end, a power transmission III gear 22 provided for driving the rolls 15 to 11 and the rolls 15
A timing belt pulley 23 provided for continuously variable transmission is attached. The power transmission gear 22 has an idle gear 24, a gear 26 fixed to a circular spline S of a differential gear machine +f/j 25 (differential unit manufactured by Harmonic Drive Systems), and spline-shaped teeth on the inner periphery. Said circular spline S
1. A flexspline 27 having two fewer teeth on the outer periphery with the same number of teeth as the Cirquera Spline S, and a circular spline having the same number of teeth as the Flexspline 27 and the same number of teeth. The spline D1 and the circular spline DK are meshed sequentially with a fixed gear 26a and a gear 28 attached to the shaft of the roll 15, thereby driving the roll 15. Further, the timing belt booth 23 is connected to a pulley 31 provided on an input shaft 30 of a continuously variable transmission 29 by a timing belt 32. In addition, continuously variable transmission 29
The output shaft 33 of the differential gear mechanism 25 passes through the center hole of the cam 34 of the differential gear mechanism 25, and the center shaft 35 is fixed to the cam 34 with a key. Pulleys 36 and 37 are respectively attached to the center shaft 35, which are connected by a timing belt 38, and Rotation is applied to the shaft 35. Between roll 15 and roll 14, roll 14
The drive systems between the rolls 13 and 13, between the rolls 13 and 12, and between the rolls 12 and 11 are the same as the drive systems between the rolls 16 and 15 described above. However, roll 15
When the roll size is 11, there is no driving source and the power is transmitted from the roll 16 shaft. The input/output direction of the differential gear mechanism 25 incorporated in the drive system between the shredded rolls 17 and 18 is roll 1.
6 and the roll 15 are reversed, with the circuit spline D side serving as an input and the S side serving as an output side (not shown).

The sheets 20 are moved forward in the direction of the arrow in a staggered state, and are preheated (heated) to a predetermined temperature, and are subjected to stretching after preheating and heat setting after stretching to complete the stretching. The film x heated by the preheating rolls elongates as it goes from between the rolls 11 to the roll 16 side, causing other problems for the reasons mentioned above. To prevent this slack...
・From the 11 side...-zyl ([jj' As the roll circumferential speed increases, the speed is increased (speed-changed) steplessly at a maximum of 5 steps for every roll. However, the roll circumferential speed standard of this preheating roll section is roll 16. In other words, roll 1 is based on roll 16.
The speed between each roll from 6 to 11 is steplessly decelerated by a maximum of 5 inches. The speed change is performed by rotating the output side of the continuously variable transmission 29 provided in the continuously variable transmission drive system to a central shaft 35 provided through the cam 34 of the differential gear mechanism 25 provided in the power transmission drive system. Change the speed and change the rotation of the cam 34,
The relative speed between the circumferential spline S and the flexspline 27 is adjusted to change the rotation speed of the circumferential spline D or S on the output side. The difference in acceleration/deceleration is determined by the difference in the input/output direction of the circular splines S and D of the differential gear mechanism 25 and the difference in the rotation direction of the cam 340.The S side is the input, the D side is the output, and the rotation direction of the cam 340 is the S side. If the direction is the same, the speed will be reduced, and if the D side is the output and the rotation direction of the cam 34 is the same as the D side, the speed will be increased.The rotation speed on the output side of the differential gear mechanism 25 is expressed by the following formula. It will be done.

In the above formula, the circular of the ND differential gear mechanism 25
212470 rotation speed, Ns, represents the rotation speed of the differential gear mechanism 25. In the case of deceleration in this embodiment (Fig. 2), the gear 22
．． 24.26.26a and 28 have the same number of teeth, the speed ratio of the differential gear mechanism 25 is +6o, the rotation speed of the o-le 16 is 45 rpm,
Rotation speed 4 of the central shaft 35 of the cam 34 of the differential gear mechanism 25
5 to 405 rl) m, the rotational speed of the roll 15 is 45 to 42.75 rpm.

[6] Effects of the Invention With the present invention, when it is necessary to change the roll circumferential speed due to selecting the optimal conditions for the drawing ratio or changing the operating conditions using unknown new materials, it is possible to easily change the roll circumferential speed in a shorter time and with high precision. You can change the roll peripheral speed.

[Brief explanation of drawings]

FIG. 1 is a front view showing one embodiment of a longitudinal stretching machine for plastic film, and FIG. 2 is a diagram showing a part of the drive system diagram of the preheating roll section. (1 to 20... roll, 25...', extraction Z
1m horizontal, 27... Flexspline, 29. ・Continuously variable transmission, 34. ・Cam, S, D...
・Saki）U・Spline. Applicant: Toshiba Machine Co., Ltd.

Claims (1)

[Claims] Bring the film surface into contact with the heated surfaces of multiple rolls,
In a longitudinal stretching machine that tensions and stretches the film in the longitudinal direction by giving a peripheral speed difference to the rolls, the peripheral speed of the roll to be driven is determined based on the roll that serves as a peripheral speed reference before or after the roll to be driven. The power transmission drive system installed between the rolls and the rolls that serve as the circumferential speed reference includes two cylinders, one for input and one for output, with the same axis, each having spline-like teeth with different numbers of teeth on the inner periphery of the cylinder. Arrange them side by side on top, and on the inside of these two cylinders over 1] have teeth with the same number of teeth and the same number of teeth as the one with the smaller number of teeth among the two cylinders. An elastic ring provided on the outer periphery is inserted, an oval cam is provided further inside the elastic ring via a ball bearing, and the elastic ring is deflected into an oval shape by the oval cam via the ball bearing. In the long sleeve, the inner teeth of the input/output cylinder and the outer teeth of the elastic ring mesh to transmit power, and due to the difference in the number of teeth, the input/output direction of the cylinder, and the rotation direction of the cam, A differential gear mechanism is provided that increases and decelerates the output side of the cylinder by changing the relative speed between the cylinder and the elastic ring having different numbers of teeth, and also serves as the circumferential speed reference separately from the power transmission drive system. A continuously variable transmission drive system is provided between the roll and the differential gear mechanism, a continuously variable transmission is incorporated in the continuously variable transmission drive system, and the continuously variable transmission is connected to the oval cam of the differential gear mechanism. By changing the rotation speed of the output side of the transmission, the rotation speed of the output side of the cylinder of the differential gear mechanism is changed, and the rotation speed of the roll to be driven can be changed steplessly. Continuously variable speed device for longitudinal stretching machine for plastic film.