A stretching device and method for making a polytetrafluoroethylene film with a bird's nest structure

Abstract

The present invention provides a stretching device for making a polytetrafluoroethylene film with a bird's nest structure, comprising a stretching mechanism, a braking mechanism installed at one end of the stretching mechanism, used to drive the stretching mechanism to rotate, and a stretching strength changing device installed at the other end of the stretching mechanism. Two groups of stretching devices are placed side by side on the ground, thereby forming a stretching roller group I and a stretching roller group II. The device can not only adjust the speed of the two groups of stretching mechanisms and the temperature of the stretching rollers as needed, but also change the stretching strength of the stretching device, and the stretching rollers of the device have good thermal conductivity when stretching a thick polytetrafluoroethylene sheet.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical cosmetic material manufacturing, and in particular relates to a stretching device and a method for manufacturing a polytetrafluoroethylene film with a bird's nest structure. Background Art

[0002] Expanded materials made of polytetrafluoroethylene membranes are widely used in the field of medical cosmetology as plastic materials for implantation into the human body. However, the internal structure of polytetrafluoroethylene membranes produced by traditional processes is neatly arranged, and the resulting expanded plastic materials have a high shrinkage rate after implantation into the human body, which cannot guarantee the implantation effect; in order to facilitate intraoperative cutting, the expanded products made of traditional polytetrafluoroethylene membranes simply increase the hardness of the products, resulting in a low product opening rate, which makes the physical properties of the polytetrafluoroethylene membranes inconsistent in two directions. After implantation into the human body, it cannot form good tissue compatibility with the human body, affecting the postoperative effect; the soft and hardness of the expanded products made of traditional polytetrafluoroethylene membranes is not stably controlled, making it difficult to produce low-deflection, high-opening-rate, easy-to-cut expanded products, resulting in poor surgical implantation effects and poor customer satisfaction.

[0003] Chinese patent publication number CN110341219A provides a polytetrafluoroethylene film with a bird's nest structure and its manufacturing process, which is carried out according to the following steps: 1) using polytetrafluoroethylene dispersed resin as raw material, adding liquid extrusion aid and mixing evenly; 2) pre-pressing the raw material after mixing evenly into an embryo; 3) pushing the pre-pressed embryo into a rod; 4) rolling the calendered rod into a polytetrafluoroethylene thick sheet; 5) high-temperature degreasing the polytetrafluoroethylene thick sheet; 6) under constant high temperature conditions, using stretching rollers of different speeds to stretch the degreased polytetrafluoroethylene thick sheet. The present invention effectively reduces the shrinkage rate of expanded products, effectively guarantees the product opening rate, and effectively controls the hardness of the product.

[0004] However, there is no stretching device for making the polytetrafluoroethylene film with the bird's nest structure in the prior art. Summary of the invention

[0005] In view of the above problems in the prior art, an object of the present invention is to provide a stretching device and method for manufacturing a polytetrafluoroethylene film with a bird's nest structure.

[0006] The present invention provides the following technical solutions:

[0007] A stretching device for making a polytetrafluoroethylene film with a bird's nest structure comprises a stretching mechanism, a braking mechanism installed at one end of the stretching mechanism for driving the stretching mechanism to rotate, and a stretching strength changing device installed at the other end of the stretching mechanism.

[0008] Specifically, the stretching mechanism includes a base; brackets symmetrically installed on both sides of the base; mounting plates are installed on the brackets; stretching roller 2 is movably installed on the mounting plate; one end of stretching roller 1 is movably installed on a device for changing the stretching strength, and the other end of stretching roller 1 passes through the bracket and is movably installed on a braking mechanism; and a cartridge heater is installed inside both stretching roller 2 and stretching roller 1.

[0009] Specifically, the stretching roller includes a roller shaft and a roller installed on the roller shaft, and the stretching rollers are a stretching roller two and a stretching roller one.

[0010] Specifically, the roller and the drum are made of base materials with higher thermal conductivity.

[0011] Specifically, the braking mechanism includes a support plate installed on the stretching mechanism; grooves are provided on both sides and the middle of the support plate; one end of the stretching roller 2 passing through the grooves on one side and the middle is installed with a pulley 1; one end of the motor passing through the groove on the other side of the support plate is installed with a pulley 2, and the motor is installed on the support plate; the guide shafts are respectively placed between the pulleys 1, and the two ends of the guide shafts are installed on the support plate through guide shaft fixing seats, and the guide shafts pass through sliders 1 and 2; the roller is installed on the slider 1; the idler wheel is installed on the slider 2; the slider 1 is connected to the support plate through a spring; the pulley 1, the pulley 2, the roller and the idler wheel are connected through belt transmission.

[0012] Specifically, the number of the guide shafts is four, which are symmetrically installed in pairs, and bushings are arranged between the slider 1 and the slider 2 and the guide shafts.

[0013] Specifically, the device for changing the tensile strength includes a ball guide shaft with both ends of the ball guide shaft installed on a bracket; a fixed block is installed on the ball guide shaft, and the stretching roller is movably installed on the fixed block; a steel wire is installed on the fixed block; a fixed plate is installed on the end of the pillar away from the fixed block; guide rollers are movably installed on both sides of the top surface of the fixed plate, and the steel wire passes through the guide rollers; a load sheet is installed on the other end of the steel wire.

[0014] Specifically, it also includes wheels installed on the bottom surface of the base and a handrail installed on one side of the base.

[0015] Specifically, the wheels are level-adjustable casters.

[0016] Based on the above device, the present invention also proposes a method for making a polytetrafluoroethylene membrane with a bird's nest structure using the above device, comprising the following steps:

[0017] S1, passing the degreased polytetrafluoroethylene thick sheet through the lower side of the stretching roller 1 and the upper side of the stretching roller 2 in the two sets of stretching mechanisms;

[0018] S2, turning on the motor and the cartridge heater through the control panel, and controlling the ratio of the speed V2 to the speed V1 of the two sets of stretching mechanisms to be 2:1 to 10:1, and heating the cartridge heater to 220°C to 300°C;

[0019] S3, the motor rotates according to the set speed to drive the second pulley to rotate, thereby driving the second pulley, the roller and the idler wheel to rotate through the belt transmission, thereby driving the first stretching roller and the second stretching roller to rotate;

[0020] S4, the cartridge heater heats the thick polytetrafluoroethylene sheet on the stretching roller 2 and the stretching roller 1 at a high temperature to be stretched;

[0021] S5, if the staff needs to adjust the tensile strength of the stretching device, they can increase or decrease the load sheet to change the position of the stretching roller 1, thereby changing the tensile strength of the stretching device;

[0022] S6, the stretched polytetrafluoroethylene film can be subsequently rolled up.

[0023] The beneficial effects of the present invention are:

[0024] The device can not only adjust the speed of two sets of stretching mechanisms and the temperature of the stretching rollers according to needs, but also change the stretching strength of the stretching device. The stretching rollers of the device have good thermal conductivity when stretching polytetrafluoroethylene thick sheets. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0026] Figure 1 is a side view of the first embodiment of the present invention;

[0027] Figure 2 yes Figure 1 Cross-sectional view at AA in the middle;

[0028] Figure 3 is a front view of the brake mechanism of the present invention;

[0029] Figure 4 It is a schematic diagram of the internal structure of the stretching roller in the present invention;

[0030] Figure 5 is a front view of the device for changing the tensile strength of the present invention;

[0031] Figure 6 In the second embodiment Figure 1 Cross-sectional view at AA in the middle. DETAILED DESCRIPTION Example

[0032] In the process of manufacturing the polytetrafluoroethylene membrane with a bird's nest structure, it is necessary to stretch the degreased polytetrafluoroethylene thick sheet using stretching rollers at different speeds under constant high temperature conditions.

[0033] The specific operation is to use stretching rollers with different speeds to stretch the degreased polytetrafluoroethylene thick sheet under constant temperature conditions of 220℃~300℃. The stretching rollers are composed of stretching roller group I and stretching roller group II. The stretching roller group I and stretching roller group II are respectively composed of 4 rollers arranged in sequence. The 4 rollers of the stretching roller group I all run at speed V1, and the 4 rollers of the stretching roller group II all run at speed V2. The ratio of speed V2 to speed V1 is 2:1~10:1. The polytetrafluoroethylene thick sheet is stretched through the stretching roller group I and the stretching roller group II in sequence.

[0034] However, there is no targeted stretching device in the prior art, so the following stretching device is designed according to the needs.

[0035] like Figure 1 As shown, the present invention provides a stretching device for making a polytetrafluoroethylene film with a bird's nest structure, comprising a stretching mechanism 1, a braking mechanism 3 installed at one end of the stretching mechanism 1 for driving the stretching mechanism 1 to rotate, and a stretching strength changing device 2 installed at the other end of the stretching mechanism 1.

[0036] Two groups of stretching devices are placed side by side on the ground, thereby forming a stretching roller group I and a stretching roller group II.

[0037] Please focus on Figure 2 The stretching mechanism 1 includes a base 103, and brackets 104 symmetrically installed on both sides of the base 103 through a support frame 106, and the number of the brackets 104 is four; a mounting plate 105 is installed on each of the brackets 104, and a stretching roller 102 is movably installed on the mounting plate 105, one end of a stretching roller 101 is movably installed on a stretching strength changing device 2, and the other end of the stretching roller 101 passes through the bracket 104 and is movably installed on a braking mechanism 3.

[0038] Please focus on Figure 4 The stretching roller 2 102 and the stretching roller 1 101 are both equipped with a cartridge heater 4.

[0039] Specifically, the stretching roller includes a roller shaft 1012 and a roller 1011 installed on the roller shaft 1012, and the stretching rollers are a stretching roller 2 102 and a stretching roller 1 101.

[0040] The roller 1012 and the drum 1011 are made of a base material with high thermal conductivity such as aluminum alloy.

[0041] Please focus on Figure 1 and Figure 3 The braking mechanism 3 includes a support plate 301 mounted on the stretching mechanism 1, and grooves 315 are provided on both sides and in the middle of the support plate 301. One end of the stretching roller 102 passing through the grooves 315 on one side and in the middle is equipped with a pulley 1 302, and one end of the motor 305 passing through the groove 315 on the other side of the support plate 301 is equipped with a pulley 2 304. The motor 305 is mounted on the support plate 301, and the guide shafts 306 are respectively placed between the pulleys 1 302, and the two ends of the guide shaft 306 are mounted on the support plate 301 through guide shaft fixing seats 307. The guide shafts 306 pass through slider 1 308 and slider 2 309, the roller 312 is installed on the slider 1 308 through a hinge pin 313 and a shaft ring, the idler wheel 314 is installed on the slider 2 309 through a hinge pin 313 and a shaft ring, the slider 1 308 is connected to the support plate 301 through a spring 311 to play a tensioning role, the spring 311 is installed on the slider 1 308 and the support plate 301 through a stretch spring support 310, and the pulley 1 302, the pulley 2 304, the roller 312 and the idler wheel 314 are connected through a belt 303.

[0042] Specifically, there are four guide shafts 306 , which are symmetrically installed in pairs, and bushings are placed between the slider 1 308 and the slider 2 309 and the guide shaft 306 to make the slider 1 308 and the slider 2 309 move more stably.

[0043] Please focus on Figure 5 The tensile strength changing device 2 includes a ball guide shaft 202 installed on the bracket 104 at both ends through a guide shaft support 203, a fixed block 201 is installed on the ball guide shaft 202, and the stretching roller 101 is movably installed on the fixed block 201. A steel wire 205 is installed on the fixed block 201 through a pillar 204, and a fixed plate 207 is installed on the end of the pillar 204 away from the fixed block 201. Guide rollers 206 are movably installed on both sides of the top surface of the fixed plate 207, respectively. The steel wire 205 passes through the guide roller 206, and the other end of the steel wire 205 is installed with a load sheet 208 through a receiving column 209.

[0044] The staff changes the position of the stretching roller 101 by adding a load sheet 208, thereby changing the stretching strength of the stretching device.

[0045] The cartridge heater 4 and the motors 305 of the two sets of stretching mechanisms 1 are externally connected and communicatively coupled to the control panel.

[0046] The control panel contains a PLC controller, which can program the numerical control system. The PLC is used as a central control system, and the touch screen is used to realize the program input and operation control of the whole machine, so as to realize the automation of the whole processing process. The control system can be used as a system that connects various actuators to move according to the logical trajectory, and the actuators can be controlled by programming to run according to the required operation steps.

[0047] The device can not only adjust the speed of the two groups of stretching mechanisms 1 and the temperature of the stretching rollers according to needs, but also change the stretching strength of the stretching device. The stretching rollers of the device have good thermal conductivity when stretching polytetrafluoroethylene thick sheets.

[0048] Based on the above device, the present invention also proposes a method for using a stretching device for making a polytetrafluoroethylene film with a bird's nest structure, comprising the following steps:

[0049] Step 1: Pass the degreased polytetrafluoroethylene thick sheet through the lower side of the stretching roller 1 101 and the upper side of the stretching roller 2 102 in the two sets of stretching mechanisms 1;

[0050] Step 2: start the motor 305 and the cartridge heater 4 through the control panel, and control the ratio of the speed V2 to the speed V1 of the two sets of stretching mechanisms 1 to be 2:1 to 10:1, and heat the cartridge heater 4 to 220° C. to 300° C.;

[0051] Step 3: The motor 305 rotates at a set speed to drive the pulley 2 304 to rotate, thereby driving the pulley 2 304, the roller 312 and the idler wheel 314 to rotate through the belt 303, thereby driving the stretching roller 1 101 and the stretching roller 2 102 to rotate;

[0052] Step 4: the cartridge heater 4 heats the thick polytetrafluoroethylene sheet on the stretching roller 2 102 and the stretching roller 1 101 at a high temperature to be stretched;

[0053] Step 5: If the staff needs to adjust the tensile strength of the stretching device, the load sheet 208 is increased or decreased to change the position of the stretching roller 101, thereby changing the tensile strength of the stretching device;

[0054] Step six, the stretched polytetrafluoroethylene film can be subsequently rolled up. Example

[0055] like Figure 6 As shown, the stretching device also includes wheels 5 installed on the bottom surface of the base 103, and a handrail 6 installed on one side of the base 103, so as to facilitate movement of the staff.

[0056] Specifically, the wheels 5 are level-adjustable casters, which facilitate the fixing of the stretching device.

[0057] The method of use of the second embodiment is the same as that of the first embodiment.

[0058] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention is described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A stretching device for making a polytetrafluoroethylene film with a bird's nest structure, characterized in that: It comprises a stretching mechanism (1), a braking mechanism (3) installed at one end of the stretching mechanism (1) and used to drive the stretching mechanism (1) to rotate, and a stretching strength changing device (2) installed at the other end of the stretching mechanism (1); The stretching mechanism (1) comprises Base (103); A bracket (104), the bracket (104) being symmetrically mounted on both sides of the base (103); A mounting plate (105), each of the brackets (104) being mounted with a mounting plate (105); A second stretching roller (102) movably mounted on a mounting plate (105); A stretching roller (101) has one end movably mounted on the stretching strength changing device (2), and the other end of the stretching roller (101) passes through a bracket (104) and is movably mounted on a braking mechanism (3); A cartridge heater (4), wherein the second stretching roller (102) and the first stretching roller (101) are both equipped with a cartridge heater (4); The stretching roller comprises a roller shaft (1012) and a roller (1011) mounted on the roller shaft (1012), and the stretching rollers are a stretching roller 2 (102) and a stretching roller 1 (101); The roller (1012) and the drum (1011) are made of aluminum alloy as a base material; The braking mechanism (3) comprises A support plate (301), the support plate (301) being mounted on the stretching mechanism (1); Grooves (315), grooves (315) are provided on both sides and in the middle of the support plate (301); Pulley 1 (302), wherein the stretching roller 2 (102) is installed with pulley 1 (302) at one end passing through the groove (315) on one side and in the middle; A motor (305) having a second pulley (304) installed at one end thereof passing through the groove (315) on the other side of the support plate (301), wherein the motor (305) is installed on the support plate (301); The guide shafts (306) are respectively placed between the pulleys 1 (302), and both ends of the guide shafts (306) are mounted on the support plate (301) via guide shaft fixing seats (307), and the guide shafts (306) pass through the slider 1 (308) and the slider 2 (309); A roller (312) mounted on the slider (308); An idler wheel (314) mounted on the second slider (309); Spring (311), the slider 1 (308) is connected to the support plate (301) via the spring (311); A belt (303), wherein the pulley 1 (302), the pulley 2 (304), the roller (312) and the idler wheel (314) are connected by the belt (303); The number of the guide shafts (306) is four, and they are symmetrically installed in pairs, and bushings are arranged between the slider 1 (308) and the slider 2 (309) and the guide shafts (306); The tensile strength changing device (2) comprises A ball guide shaft (202), with both ends of the ball guide shaft (202) mounted on a bracket (104); A fixed block (201), wherein the ball guide shaft (202) is mounted with the fixed block (201), and the stretching roller 1 (101) is movably mounted on the fixed block (201); A steel wire (205), the fixing block (201) being provided with the steel wire (205); A fixing plate (207), wherein the fixing plate (207) is mounted on one end of the pillar (204) away from the fixing block (201); Guide rollers (206) are movably mounted on both sides of the top surface of the fixing plate (207), and the steel wire (205) passes through the guide rollers (206); A load sheet (208), wherein the other end of the steel wire (205) is provided with a load sheet (208).

2. A stretching device for producing a polytetrafluoroethylene film with a bird's nest structure according to claim 1, characterized in that: It also includes wheels (5) mounted on the bottom surface of the base (103), and a handrail (6) mounted on one side of the base (103).

3. A stretching device for producing a polytetrafluoroethylene film with a bird's nest structure according to claim 2, characterized in that: The wheels (5) are level-adjustable casters.

4. A method for making a stretching device for a polytetrafluoroethylene film with a bird's nest structure using the stretching device as claimed in claim 3, characterized in that: The following steps are involved: S1, passing the degreased polytetrafluoroethylene thick sheet through the lower side of the stretching roller 1 (101) and the upper side of the stretching roller 2 (102) in the two sets of stretching mechanisms (1); S2, turning on the motor (305) and the cartridge heater (4) through the control panel, and controlling the ratio of the speed V2 to the speed V1 of the two sets of stretching mechanisms (1) to be 2:1 to 10:1, and heating the cartridge heater (4) to 220° C. to 300° C.; S3, the motor (305) rotates according to a set speed to drive the second pulley (304) to rotate, thereby driving the roller (312) and the idler wheel (314) to rotate through the belt (303), thereby driving the first stretching roller (101) and the second stretching roller (102) to rotate; S4, at the same time, the cartridge heater (4) heats the thick polytetrafluoroethylene sheet wrapped around the second stretching roller (102) and the first stretching roller (101) so that the sheet is stretched at a high temperature; S5, if the staff needs to adjust the tensile strength of the stretching device, the staff increases or decreases the load sheet (208) to change the position of the stretching roller 1 (101), thereby changing the tensile strength of the stretching device; S6, the stretched polytetrafluoroethylene film is subsequently rolled up.

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