Ultrasonic rapid welding process for cutting and splicing tire fiber cords

Abstract

The present invention relates to the technical field of tire fiber cord splicing, and specifically provides an ultrasonic rapid welding process for splicing tire fiber cords after cutting, the welding process comprising: obtaining the tail position of a first cord and the head position of a second cord; picking up the head of the second cord and moving it to the tail of the first cord, so that the tail of the first cord and the head of the second cord overlap; adjusting the welding head of a first welding device so that it is located below the overlapping position of the first cord and the second cord, controlling a clamping block to clamp above the overlapping position of the first cord and the second cord, the clamping block and the welding head clamp the first cord and the second cord, starting an ultrasonic welding program, the welding head welds the overlapping part of the first cord and the second cord, and after welding is completed, lifting the clamping block, wherein the first welding device is an ultrasonic welding structure; the present invention has high welding efficiency and high welding quality, and at the same time, a small overlapping area.

Description

Technical Field

[0001] The invention relates to the technical field of tire fiber cord splicing, and in particular to an ultrasonic rapid welding process for splicing tire fiber cords after cutting. Background Art

[0002] The tire carcass cord layer is its main load-bearing component and the tire's load-bearing skeleton layer. In the tire production process, the single cord cut by the cutting machine needs to be spliced ​​into a whole strip in a specific direction, and then rolled up with an I-shaped wheel for use.

[0003] When splicing existing tire fiber cords, the two ends of the two cords are manually overlapped together, and the single cord is superimposed and pasted when the head and tail are spliced, and then bonded together by roller rolling. Due to manual operation, the error is large, and the dynamic balance data of the produced tire is often not ideal due to the large area of ​​the superimposed part. In addition, the large overlapping area of ​​the cord also increases the loss of materials. Moreover, the efficiency of manual splicing is low, which also increases the labor cost. Therefore, the present application proposes an ultrasonic rapid welding process for splicing tire fiber cords after cutting. Summary of the invention

[0004] The purpose of the present invention is to provide a rapid ultrasonic welding process for splicing tire fiber cords after cutting, so as to solve the problem of low efficiency of the current tire fiber cord splicing process.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A rapid ultrasonic welding process for cutting and splicing tire fiber cords, the welding process comprising the following steps:

[0007] Obtaining the tail position of the first curtain and the head position of the second curtain;

[0008] Pick up the head of the second curtain and move it to the tail of the first curtain so that the tail of the first curtain overlaps with the head of the second curtain;

[0009] The welding head of the first welding device is adjusted so that it is located below the overlapping position of the first curtain and the second curtain, and the pressing block is controlled to press above the overlapping position of the first curtain and the second curtain, and the pressing block and the welding head clamp the first curtain and the second curtain, and the ultrasonic welding program is started. The welding head welds the overlapping part of the first curtain and the second curtain. After the welding is completed, the pressing block is lifted, wherein the first welding device is an ultrasonic welding device;

[0010] Conveying welded cord.

[0011] Furthermore, the overlapping width between the tail of the first cord and the head of the second cord is 1 mm.

[0012] Furthermore, the ultrasonic frequency of the ultrasonic welding device is 20-40KHz.

[0013] Furthermore, the welding time of the welding head is less than 1 s.

[0014] Furthermore, the amplitude of the welding head of the ultrasonic welding device is greater than 30um.

[0015] Furthermore, the pressing force of the welding head of the ultrasonic welding device is greater than 100N.

[0016] Furthermore, after the welded cord fabric is transferred, the following steps are also included:

[0017] Control the movement of the welded cord fabric to a preset distance;

[0018] The welding head of the second welding device is adjusted so that it is located above the overlapping position of the first curtain and the second curtain, the welding head of the second welding device is controlled to press against the unwelded area at the overlapping position of the first curtain and the second curtain, and the second welding device is started to weld the unwelded area, wherein the second welding device is an ultrasonic welding device.

[0019] Furthermore, after welding is completed, cooling water is introduced into the pressing block to reduce the temperature of the pressing block and increase the cooling speed of the welding point between the first cord and the second cord.

[0020] In summary, the present invention has the following beneficial effects compared with the prior art:

[0021] The ultrasonic rapid welding process for splicing tire fiber cords after cutting disclosed in an embodiment of the present invention picks up the second cord and moves it onto the first cord so that the tail of the first cord overlaps the head of the second cord. Compared with the traditional splicing method, the ultrasonic welding process has high welding efficiency and high welding quality. At the same time, the overlapping area is small, which saves materials. At the same time, the strength of the splicing between the first cord and the second cord is higher. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the process of ultrasonic rapid welding of tire fiber cord after cutting in an embodiment of the present invention. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0024] like Figure 1 As shown, an embodiment of the present invention provides a tire fiber cord fabric cutting and splicing ultrasonic rapid welding process, the welding process comprising:

[0025] Step S100, obtaining the tail position of the first curtain and the head position of the second curtain;

[0026] Step S200, picking up the head of the second curtain and moving it to the tail of the first curtain, so that the tail of the first curtain overlaps with the head of the second curtain;

[0027] Step S300, adjusting the welding head of the first welding device so that it is located below the overlapping position of the first curtain and the second curtain, controlling the pressing block to press above the overlapping position of the first curtain and the second curtain, the pressing block and the welding head clamp the first curtain and the second curtain, starting the ultrasonic welding program, the welding head welds the overlapping part of the first curtain and the second curtain, and after the welding is completed, lifting the pressing block, wherein the first welding device is an ultrasonic welding device;

[0028] Step S400: conveying the welded cord fabric.

[0029] Specifically, in the present embodiment, when welding and splicing tire fiber cords, it is necessary to splice the tail of the first cord and the head of the second cord together. Before welding, the tail of the first cord and the head of the second cord located on the transmission belt are identified, and then the head position of the second cord is picked up by a robot and stacked on the tail position of the first cord, so that the tail of the first cord and the head of the second cord overlap. After the second cord is placed, the welding head of the first welding device is moved to the overlapping position of the first cord and the second cord, and the ultrasonic first welding device is started. The ultrasonic wave generated by the welding head can drive the first cord and the second cord to vibrate at a high frequency. The heat generated by the vibration causes the overlapping part of the first cord and the second cord to melt and combine instantly, thereby completing the welding of the first cord and the second cord.

[0030] The ultrasonic rapid welding process for splicing tire fiber cords after cutting disclosed in an embodiment of the present invention picks up the second cord and moves it onto the first cord so that the tail of the first cord overlaps the head of the second cord. Compared with the traditional splicing method, the ultrasonic welding process has high welding efficiency and high welding quality. At the same time, the overlapping area is small, which saves materials. At the same time, the strength of the splicing between the first cord and the second cord is higher.

[0031] Specifically, in step S100, the tail of the first curtain and the head of the second curtain are obtained through the visual system, wherein the recognition algorithm of the visual system is the prior art, and when the first curtain and the second curtain follow the conveyor belt, the positions of the first curtain and the second curtain in the field of view of the visual system are different, such as the first curtain is located at the downstream position in the conveying direction, and the second curtain is located at the upstream position in the conveying direction. The first curtain and the second curtain are distinguished by identifying the positions of the curtains in the field of view, and then the edge positions of the first curtain and the second curtain are identified by the edge recognition algorithm, then the edge of the first curtain close to the second curtain is the tail of the first curtain, and the edge of the second curtain close to the first curtain is the head of the second curtain. At the same time, the visual system also identifies the coordinates of the edges of the first curtain and the second curtain through the edge recognition algorithm, so as to facilitate the robot to pick up the second curtain.

[0032] The edge recognition algorithm is a prior art, such as an algorithm for industrial cameras to recognize the edges of objects.

[0033] In step S200, the robot picks up the second curtain, such as a robot with a suction cup device sucking the second curtain through the suction cup device. Before the robot picks up the second curtain, the control unit of the robot obtains image information and recognition results (such as edge position information of the first curtain and the second curtain, and position information of the tail of the first curtain and the head of the second curtain) collected by the visual system to control the execution end of the robot to move to a preset position. The robot fixes the second curtain and drives the second curtain to move to the second curtain. At this time, the second curtain overlaps with the first curtain.

[0034] As a preferred implementation manner in this embodiment, the overlapping width of the head of the second cord and the tail of the first cord is 1 mm. In the traditional splicing process, the centering accuracy of the first cord and the second cord is ±1 mm, and the overlapping width of the first cord and the second cord is 3 to 4 mm. In this embodiment, the overlapping size of the first cord and the second cord is small, and each joint saves about 3 mm. If 10,000 tires are calculated, 30 meters of cord can be saved. At the same time, the overlapping size of the first cord and the second cord is small, and the dynamic balance and uniformity of the finished tire are relatively good. Due to the small overlapping size of the splicing, the material is more evenly distributed in the circumferential direction, which can effectively improve the dynamic balance of the tire.

[0035] In step S300, after the robot overlaps the first curtain and the second curtain, the ultrasonic first welding device presses the welding head to the overlapping position of the first curtain and the second curtain, and the amplitude transformer of the welding head transmits mechanical vibration to the first curtain and the second curtain, and the overlapping position of the first curtain and the second curtain generates high-frequency vibration, and the friction between the first curtain and the second curtain generates heat, and the generated heat melts the material of the contact surface of the first curtain and the second curtain, so that the overlapping part between the first curtain and the second curtain is combined, thereby completing the welding work;

[0036] As a preferred implementation in this embodiment, the ultrasonic frequency of the first ultrasonic welding device is 20-40KHz. Under this vibration frequency, the welding efficiency can meet the requirements and the welding strength is high.

[0037] Preferably, the welding time of the welding head is less than 1s. The welding time between the first curtain and the second curtain affects the tensile strength of the first curtain and the second curtain. A short time is likely to cause a loose welding, while a long time is likely to cause excessive melting, which can also cause a loose welding. In this embodiment, the welding time between the first curtain and the second curtain is 0.2s~1s;

[0038] Preferably, the welding time of the first curtain fabric and the second curtain fabric is 0.5 s.

[0039] As a preferred implementation in this embodiment, the amplitude of the welding head of the first ultrasonic welding device is greater than 30um, so as to obtain higher welding quality;

[0040] As a preferred implementation in this embodiment, the pressing force of the welding head of the first ultrasonic welding device is greater than 100N, so as to obtain higher welding quality; in this embodiment, the pressing force of the welding head is 120N.

[0041] In this embodiment, the amplitude transformer on the welding head of the ultrasonic first welding device is in the shape of a long strip, so that the welding head can cover the overlapping part of the first curtain and the second curtain. The ultrasonic first welding device is a prior art. The welding head controls its rotation through a rotating device, so that the welding head can adapt to the curtain cut at different angles. The pressing block on the manipulator that is lifted or connected by a lifting device is in the shape of a long strip. When welding the first curtain and the second curtain, the pressing block and the welding are located on the upper and lower sides of the contact part of the first curtain and the second curtain, so that the welding head and the pressing block clamp the first curtain and the second curtain.

[0042] It should be noted that the lifting device can also be moved by a horizontal moving device, so that the welding head and the clamping block can be appropriately adjusted according to the positions of the first curtain and the second curtain. The horizontal moving device is a prior art, such as a linear motor, a screw moving structure, etc.

[0043] The pressing block is also fixed to the lifting device by a rotating device, such as a screw rotating device, for adjusting the angle of the pressing block;

[0044] In this embodiment, in order to facilitate the adjustment of the pressing block, the pressing block is installed on the mechanical arm.

[0045] In step S400, after welding is completed, the transmission belt conveys the welded first and second curtains. At the same time, the visual system collects images in real time and identifies the tail of the second curtain. After identifying the tail, the control unit controls the conveyor belt to stop running, and then executes steps S100 to S300 to weld the second and third curtains, and so on, until the welding of all curtains is completed.

[0046] As a preferred implementation in this embodiment, the following steps are further included after the welded curtain fabric is conveyed:

[0047] Step S500, controlling the welded curtain to move a preset distance;

[0048] Step S600, adjusting the welding head of the second welding device so that it is located above the overlapping position of the first curtain and the second curtain, controlling the welding head of the second welding device to press against the unwelded area at the overlapping position of the first curtain and the second curtain, starting the second welding device, and welding the unwelded area, wherein the second welding device is an ultrasonic welding device;

[0049] In this embodiment, since ultrasound cannot perform large-surface welding, in this embodiment, the amplitude transformer on the welding head is arranged in an equidistant manner to be in a long strip shape. During welding, the welding head of the first welding device welds the first curtain and the second curtain at an equidistant distance, so that there is an unwelded area at the contact portion of the first curtain and the second curtain. Therefore, in this embodiment, the first curtain and the second curtain are welded for a second time by the second welding device. The first welding device and the second welding device have the same structure. During the secondary welding, the first curtain and the second curtain are also pressed by the pressing block;

[0050] It should be noted that the pressing blocks used in the first welding and the second welding are two devices with completely identical structures.

[0051] As a preferred implementation of this embodiment, after welding is completed, cooling water is introduced into the pressing block to reduce the temperature of the pressing block and increase the cooling speed of the welding point between the first curtain and the second curtain;

[0052] A flow channel for coolant is provided inside the clamping block, and the clamping block is connected to a cooling system. The coolant cools the clamping block by flowing in the clamping block, thereby cooling the welding area to achieve rapid cooling. The clamping blocks during the first and second welding are both connected to the cooling system, and the cooling system is prior art.

[0053] In order to better illustrate the effect of the present application, in this embodiment, a tire fiber cord with a thickness of 1.2 mm and a width of 25 mm is welded and subjected to a tensile test under the same parameters as an unwelded tire fiber cord, wherein the overlapping width of the tire cord is 1 mm, as shown in the following table:

[0054]

[0055] This test was carried out on No. 1 and No. 2 cords, and each cord was tested 3 times. The welded group was stretched after welding, and the non-welded group was directly subjected to the stretching test. The data of the tensile force group refers to the tensile force when the cord is stretched to 150% (the cord does not break), and the data of the tensile strength group refers to the cord breaking data.

[0056] After testing, under the condition of a clamping force of 120N, a welding time of 0.5s, and ultrasonic welding with a frequency of 20KHz and an amplitude of 36um, the joint strength data of the first and second cords are as follows: when the cord with a joint is stretched to 150% (the cord does not break), the average tensile force is 15.29 N / 25cm, and when the cord without a joint is stretched to 150% (the cord does not break), the average tensile force is 15.77 N / 25cm; when the cord with a joint is stretched to break, the average tensile force is 28.6 N / 25cm, and when the cord without a joint is stretched to break, the average tensile force is 29.79N / 25cm. From the above data, it can be seen that the parameters of the cord after welding are almost the same as those of the unwelded cord, and the strength of the cord joint is close to the strength of the unwelded cord, indicating that the ultrasonic welding method can greatly improve the welding strength.

[0057] The terms used in the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The singular forms "a", "the" and "the" used in the present invention and the appended claims are also intended to include plural forms unless the context clearly indicates other meanings. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0058] It should be understood that although the terms first, second, third, etc. may be used in the present invention to describe various information, these information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present invention, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining".

[0059] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A tire fiber cord fabric cutting and splicing ultrasonic rapid welding process, characterized in that: The welding process comprises the following steps: Obtaining the tail position of the first curtain and the head position of the second curtain; Pick up the head of the second curtain and move it to the tail of the first curtain so that the tail of the first curtain overlaps with the head of the second curtain; The welding head of the first welding device is adjusted so that it is located below the overlapping position of the first curtain and the second curtain, and the pressing block is controlled to press above the overlapping position of the first curtain and the second curtain, and the pressing block and the welding head clamp the first curtain and the second curtain, and the ultrasonic welding program is started. The welding head welds the overlapping part of the first curtain and the second curtain. After the welding is completed, the pressing block is lifted, wherein the first welding device is an ultrasonic welding device; Convey the welded cord fabric; After the welded cord is transferred, the following steps are also included: Control the movement of the welded cord fabric to a preset distance; Adjusting a welding head of a second welding device so that it is located above the overlapping position of the first curtain and the second curtain, controlling the welding head of the second welding device to press against the unwelded area at the overlapping position of the first curtain and the second curtain, starting the second welding device, and welding the unwelded area, wherein the second welding device is an ultrasonic welding device; After welding is completed, cooling water is introduced into the pressing block to reduce the temperature of the pressing block and increase the cooling speed of the welding point between the first cord and the second cord.

2. The ultrasonic rapid welding process for cutting and splicing tire fiber cords according to claim 1 is characterized in that: The overlapping width between the tail of the first cord and the head of the second cord is 1 mm.

3. The ultrasonic rapid welding process for cutting and splicing tire fiber cords according to claim 1 is characterized in that: The ultrasonic frequency of the ultrasonic welding device is 20-40KHz.

4. The ultrasonic rapid welding process for cutting and splicing tire fiber cords according to claim 1 is characterized in that: The welding time of the welding head is less than 1 s.

5. The ultrasonic rapid welding process for cutting and splicing tire fiber cords according to claim 1 is characterized in that: The amplitude of the welding head of the ultrasonic welding device is greater than 30um.

6. The ultrasonic rapid welding process for cutting and splicing tire fiber cords according to claim 1 is characterized in that: The pressing force of the welding head of the ultrasonic welding device is greater than 100N.

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