KR20100053948A - Device of controlling extruder of non-product strip for tire and method thereof - Google Patents

Abstract

PURPOSE: A device and a method for controlling extrusion of semi-products of tire are provided to stabilize the dimension of semi-products by regulating the speed of extrusion line. CONSTITUTION: A device for controlling extrusion of semi-products of tire comprises an extruder(10), a lead-out conveyor(20), a compression conveyor(30), first and second scale conveyors(40,80), a cooling conveyer(60), a loader(100), transfer conveyors(50,70,90), a width detection sensor(120), a distance marker(130), distance detection sensors(140a,140b,140c), and a controller(110). The controller measures the distance between distance marks of an extruded product with the first distance detection sensor, and computes the actual shrinkage rate by comparing the distance mark with initial distance mark. The speed of the lead-out conveyor, compression conveyor, and cooling conveyor is reduced at the actual shrinkage rate less than the computed shrinkage rate, while the speed is raised at the actual shrinkage rate greater than the computed shrinkage rate.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a semi-finished product extrusion control apparatus for a tire,

The present invention relates to a semi-finished product extrusion control apparatus for a tire and an extrusion method thereof, and more particularly, to a semi-finished product extrusion control apparatus for a tire by controlling the extrusion speed in consideration of die expansion and contraction So as to improve the quality of the tire.

Generally, semi-finished product extrudates for molding tires, especially semi-finished product extrudates that make up treads, account for up to 50% of the rubber compound content by weight.

Therefore, the dimensional uniformity of the extrudate is an important goal of the manufacturing process since the quality of the extrudate has a great influence on tire performance.

However, since rubber compounds are visco-elastic materials with both viscous and elastic properties, they exhibit different behaviors from other materials that are only viscous or elastic, making it difficult to achieve the desired uniformity .

Furthermore, unlike viscous fluids, the flow of viscoelastic materials, such as rubber compounds, has elastic memory to recover quickly after experiencing strain due to stress in the extruder, Shrinkage occurs when the die swells or the flow stops, causing the tensile force in the fluid to move the particles backward.

That is, in the extruder, the deformed particles are restored to their original shape as they pass through the extrusion die head, and exhibit elastic recovery. Further, when the extrusion flow is stopped, a recoil phenomenon occurs backward. Therefore, the expansion and contraction phenomena of the viscoelastic material are different due to the lapse of time, but they coexist and can not be considered separately from each other.

Therefore, the expansion and contraction phenomenon necessarily occurs when the rubber compound, which is a viscoelastic material, is extruded. By effectively controlling the expansion and contraction of the rubber compound, it is possible to ensure the uniformity of the dimensions of the extrudate at the required level. Finally, Is required.

Numerous efforts have been made by many utilities and tire manufacturers to improve the dimensional uniformity of semi-finished products to the present day, and many of these efforts are focused on controlling the extrusion lines.

In the prior art, Korean Patent Publication No. 2005-0028547 discloses a method for measuring the width of extrudate, which is measured through a width measuring device at the upper end of a drawing conveyor located at a stage immediately after the extruder head to uniformize the width and weight of the extrudate, An extruded semi-finished product control device of an extruder is disclosed to adjust the speed of an extruder using a weight value measured through a continuous metering machine.

However, in the case of the extrusion semi-finished product control device of the extruder described above, the applied extruder for field use usually measures the width and weight in real time and feeds back more than 4.5 inches, especially in the case of treads, Controlling the speed of the extruder means that the speed changes at every moment.

Therefore, it is preferable to keep the speed of the extruder evenly, because there is a possibility that the difference in the extruded flow rate in the extruder may be caused by the above-mentioned speed change, or the change in width due to the flow rate difference may be accompanied more more. There is a limit in controlling the shrinkage of the extrudate on the long extrusion line because it controls only the outgoing conveyor and the scale conveyor which are part of the extrusion lines composed of several conveyors.

In addition, U.S. Patent No. 4,097,566, which was filed in the same year, discloses a control method based on the weight of the extrudate. That is, by controlling the speed of the extruder and the outgoing conveyor by comparing the weights of the two scale conveyors with each other, a dancer is provided between the conveyors of each section to control the speed of the conveyor by each section Control method.

However, in the first scale conveyor immediately after the extruder, the expanded portion is not yet reduced so that the weight per unit length is high. On the second scale conveyor, the long extrusion line and the cooling process are performed to remove much of the expanded portion, Therefore, there is always a weight deviation between these two scale conveyors.

Therefore, in order to reduce the deviation between them, the speed of the extruder must be changed, and the flow rate changes inevitably accompanied by the speed change, and therefore, the weight deviation must be continuously generated.

In order to solve the above problems, an object of the present invention is to calculate a die expansion and shrinkage ratio generated during semi-finished product extrusion, calculate a shear rate and a shrinkage rate at a specific time zone, To control the speed of the semi-finished product, and to stabilize the dimension of the semi-finished product.

In order to accomplish the above object, the present invention provides a semi-finished product extrusion control apparatus for a tire, comprising: an extruder for extruding a rubber compound into a strip-shaped semi-finished product; A draw-out conveyor provided continuously to the die head of the extruder; A width detection sensor provided on the drawing conveyor for measuring a width of the semi-finished product drawn out from the head of the compressor; A distance indicator provided at one side of the width detection sensor for displaying a distance at predetermined time intervals on the semi-finished product drawn out from the extruder head; A forced shrinkage conveyor provided continuously to the draw-out conveyor for shrinking the semi-finished product strip conveyed from the draw-out conveyor; A first scale conveyor provided continuously to the forced contraction conveyor for detecting the weight per unit length of the conveyed semi-finished product; A cooling conveyor installed continuously to the first scale conveyor and cooling the conveyed semi-finished product; A second scale conveyor provided continuously to the cooling conveyor for detecting the weight per unit length of the semi-finished product conveyed through the cooling conveyor; A second scale conveyor continuously installed on the second scale conveyor, for loading the conveyed semi-finished product; A transfer conveyor arranged between the first scale conveyor, the cooling conveyor, the second scale conveyor, and the stacker, respectively, for conveying the semi-finished product; A distance sensor installed on each conveying conveyor for measuring the distance between the distance indications displayed on the semi-finished product at the distance indicator; And calculating the expansion and contraction amount of the semi-finished product measured from the width detecting sensor, calculating the weight and shearing rate per unit length of the semi-finished product measured through the first scale conveyor and the second scale conveyor, The extrusion conveyor, the steel material compression conveyor, the first scale conveyor, the cooling conveyor, the second scale conveyor, and the extrusion by the conveying conveyors are calculated by calculating the shrinkage rate in the time zone, And a control unit for controlling the speed of the vehicle.

 The distance indicator may include a spray paint spraying a color paint or a photosensitive paint.

The semi-finished product extrusion control method for a tire according to the present invention comprises the steps of: measuring a width of a semi-finished product extruded in a strip form in an extruder head; Calculating a die expansion using the semi-finished product width; Calculating a shrinkage ratio of the semi-finished product using the die swell; Calculating a shear rate; Calculating a shrinkage ratio at a specific time zone using the shrinkage ratio; And calculating a proper extrusion speed through a shrinkage ratio in a specific time zone, and controlling an extrusion speed by comparing an appropriate extrusion speed with a current extrusion speed.

 The die swell (DS)

Lt; / RTI >

Here, l1 is the width of the extrusion die head and l2 is the width of the extruded semi-finished product.

을 통해 연산될 수 있다. 여기서, m은 반제품을 이루는 고무 컴파운드의 특성치이다.The shrinkage ratio (SR)

Lt; / RTI > Here, m is a characteristic value of a rubber compound which forms a semi-finished product.

 The shear rate (R)

Lt; / RTI >

Where Q is the amount of extrusion (volumetric flow rate), w is the width of the die head of the extruder, H is the height of the die head of the extruder, and sigma w is the shear stress.

 The shrinkage ratio (L)

Lt; / RTI >

Where k is a constant associated with shear rate, t is time, and a and b are constants that depend on the rubber compound properties.

According to the semi-finished product extrusion control apparatus for a tire and the control method therefor of the present invention, the die expansion and contraction amount is calculated by using the width value of the semi-finished product measured from the width detection sensor, and the amount of expansion and contraction is measured through the first scale conveyor and the second scale conveyor The shrinkage rate in a specific time zone is calculated using the shrinkage amount, the appropriate extrusion rate calculated using the shrinkage rate in a specific time zone is calculated, and the extrusion conveyor, the steel material compression conveyor, the first scale It is possible to improve the quality of the tire by stabilizing the dimensions during the extrusion of the semi-finished product controlling the extrusion speed by the conveyor, the cooling conveyor, the second scale conveyor, and the conveying conveyors.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and the same or similar components are denoted by the same reference numerals throughout the specification.

1 is a schematic view showing a tire semi-finished product extrusion control apparatus according to an embodiment of the present invention.

1, the tire semi-finished product extrusion control apparatus 1 includes an extruder 11, a drawing conveyor 20, a forced compression conveyor 30, a first scale conveyor 40, a cooling conveyor 60, 2 scale conveyor 80, stacker 100, conveying conveyors 50, 70 and 90, width sensor 120, distance indicator 130, distance sensor 140a 140b 140c and controller 110, .

The extruder 11 presses the rubber compound constituting the semi-finished product 5 and pushes it through the die head 11 into the semi-finished product 5 in the form of a strip.

The drawing conveyor 20 is provided continuously to the die head 11 of the extruder 10 so that the semi-finished product extruded from the die die head 11 is taken out in a strip form (hereinafter referred to as a semi-finished product strip).

On the other hand, the width detecting sensor 120 measures the width 12 of the semi-finished product strip 5 which is installed on the draw-out conveyor 20 and drawn out through the die head 11.

The width detection sensor 120 is electrically connected to the controller 110 and transmits the width 12 of the measured semi-finished product strip to the controller 110.

The distance indicator 130 is installed on one side of the width detection sensor 130 on the draw-out conveyor 20, and displays the distance on the drawn-out semi-finished strip 5 every set time.

The distance indicator 130 is electrically connected to the controller 110 and is controlled to display a distance on the semi-finished strip 5 in accordance with a control signal generated from the controller 110.

In the present embodiment, the distance indicator 130 is an injection nozzle that is controlled by the controller 110 so as to eject the color paint and the photosensitive paint.

 The forced contraction conveyor 30 is provided continuously to the draw-out conveyor 20 and continuously compresses and shrinks the semi-finished product strip 5 conveyed from the draw-out conveyor 20.

The first scale conveyor 40 is installed continuously with the forced contraction conveyor 30 and load cells 45 for detecting the weight per unit length of the transported semi-finished product strip 5 are installed below.

Thus, the first scale conveyor 40 passes through the forced shrinkage conveyor 30 and is shrunk, and then detects the weight value per length of the semi-finished strip 5.

The cooling conveyor 60 is provided continuously to the first scale conveyor 40 with the first conveying conveyor 50 therebetween and successively cools the conveyed semi-finished product strips 5.

The second scale conveyor 80 is installed continuously to the cooling conveyor 60 through the second conveying conveyor 70 and the load cells 85 are installed below the cooling conveyor 60.

Thus, the load cells 85 are electrically connected to the controller 110 and are transmitted to the controller 110 through the cooling conveyor 60 and detecting the weight value per length of the cooled and shrunk semi-finished strip 5.

The loader 100 is installed continuously with the second scale conveyor 80 via the third conveying conveyor 90 so as to load the semi-finished product conveyed through the third conveying conveyor 90.

In the present embodiment, the stacker 100 exemplifies that the extruded semi-manufactured strip is rolled into a roll shape. However, the present invention is not limited to this, It can also be stored.

On the other hand, on the first, second, and third conveying conveyors 50, 70 and 90, a distance detection sensor 120 for measuring the distance between the distance indications displayed on the semi-finished product strip 5 by the distance indicator 120, 140a, 140b and 140c.

The first distance sensing sensor 140a is installed on the first conveying conveyor 40 and after being passed through the forced shrinking conveyor 30 and retracted, the weight per length is measured primarily in the first scale conveyor 40 Measure the distance change value between the distance indications for the semi-finished product strip 5 in the state.

The second distance sensing sensor 140b is installed on the second conveying conveyor 70 to measure the distance variation values between the distance indications displayed on the semi-finished product strip 5 cooled and shrunk through the cooling conveyor 60, .

The third distance sensing sensor 140c is installed on the third conveying conveyor 90 and measures the weight value per length in the second scale conveyor 80. Thereafter, Continuously measures the distance change value between the distance indications displayed on the strip 5.

Each of the first, second and third distance sensing sensors 140a, 140b and 140c is electrically connected to the controller 110 so that distance variation values of the measured semi-manufactured strip, that is, ).

The controller 110 calculates the amount of expansion and contraction of the die by using the value of the width 12 of the semi-finished product strip 5 measured from the width detecting sensor 120 and calculates the amount of expansion and contraction of the first scale conveyor 40 and the second scale conveyor 80 And calculates the shrinkage rate in a specific time zone using the shrinkage amount, the weight per length, and the shearing rate, and calculates the shrinkage rate at the specific time zone So that the overall extrusion speed of the extrusion line is controlled.

On the other hand, the controller 110 controls each of the extrusion conveyors 20, the forced shrink conveyor 30, the first scale conveyor, the cooling conveyor, and the conveying conveyors 50, 70, 90 to control the speed of the extrusion line Is connected to the drive motors (25, 35, 45, 55, 75, 95) to control the extrusion speed of the entire extrusion line.

FIG. 2 is a view sequentially showing a tire semi-finished product extrusion control process according to an embodiment of the present invention.

2, the semi-finished product extrusion control process for a tire includes a semi-finished product strip width measuring step S1, a die expansion calculating step S2, a shrinkage calculating step S3, a shearing speed calculating step S4, A shrinkage rate calculation step S5 of the first embodiment, and an extrusion rate control step S6.

In the extruder 102, a die head 11 is mounted for imparting a shape to the semi-finished product strip 5, and a die expansion phenomenon occurs in which the rubber compound expands while exiting the die head 11.

As described above, in order to calculate the die expansion of the semi-finished product strip 5 that exits from the die head 11, it is necessary to first measure the width 12 of the semi-finished product strip 5 which is extruded out from the die head 11 .

Thus, in the width measuring step S1 of the semi-finished product strip, the width 12 of the semi-finished product strip 5 drawn out from the outlet of the die head 11 of the extruder 10 is measured.

3 is a schematic perspective view showing a width measurement state of a semi-finished product by the width detection sensor of FIG.

3, the width 12 of the semi-finished product strip 5 taken out from the die head 11 of the extruder 10 is set at a position on the upper side of the drawing conveyor 20 adjacent to the outlet side of the die head 11 Measured by the installed width sensing sensor 120 and the measured width 12 value of the semi-finished product strip 5 is transmitted to the controller 110. [

2, in the die expansion calculation step S2, the width 12 of the measured semi-finished product strip 5 is compared with the width 11 of the die head of the extruder to calculate the die expansion DS . The above-mentioned die expansion (DS) can be obtained by the following equation (1).

Where l1 is the width of the die head 11 of the extruder 10 and l2 is the width of the extruded semi-finished strip.

On the other hand, the die expansion phenomenon is different depending on the composition included in each rubber compound forming the semi-finished product strip, that is, the kind and amount of the raw material and the processing conditions of the extruder.

Further, in the die head 11 of the extruder 10, a shrinkage shape due to stress relaxation together with the die expansion DS described above occurs.

The shrinkage rate SR is calculated based on the characteristics of each rubber compound forming the semi-finished product strip 5 and the die swell DS).

Therefore, the shrinkage ratio SR can be obtained by the following equation (2) by applying the characteristic of the rubber compound that forms the semi-product strip and the die swell (DS).

Where DS is the die expansion and m is the characteristic value of the rubber compound forming the semi-finished strip 5

It is preferable that the shrinkage is minimized or the shrinkage does not proceed further until the shrinkage is maximally performed in the conventional extrusion line and the shrinkage is performed by the stacker 100 after cutting to a predetermined length.

In the shear rate calculation step S4, the weight value per unit length of the semi-finished product strip 5 is measured through the first scale conveyor 40 and the second scale conveyor 80, and the weight value per unit length of the semi-finished product strip The shear rate R is calculated. The shear rate R depends largely on the extruded amount of the semi-finished product strip 5 and can be calculated through Equation (3).

Where d is the density, w is the die head width of the extruder, H is the height of the die head of the extruder, and? W is the shear stress.

In the shrinkage rate calculating step S5 in a specific time zone, the shrinkage rate L in a specific time zone is calculated using the export rate SR and the shearing rate R described above.

Where k is a constant associated with the shear rate R, t is the time, and a and b are constants dependent on the rubber compound property

Therefore, when the shrinkage rate (L) value at a specific time is obtained, the time at which the extreme end of the extrusion line reaches the end of the extrusion line, that is, the time immediately before the stacking 11, is obtained. To decide whether to

That is, since the length of the extrusion line is known, it is possible to know the appropriate time to reach the final stacker 100 of the extrusion line as compared with the current extrusion speed of the semi-finished product strip 5, that is, the speed of the extrusion line, It is possible to know the proper amount of shrinkage on the extrusion line as compared with the shrinkage rate in the time zone.

In the extrusion speed control step (S6), the optimum extrusion speed is calculated through the shrinkage ratio (L) at a specific time, and the extrusion speed is controlled by comparing the optimum extrusion speed and the extrusion speed of the current extrusion line.

Therefore, after the semi-finished product strip 5 passes through the die head 11 of the extruder 10 in the extrusion rate control step S6, the operation speed of the extrusion line is automatically set, and the length indicator 120 and the length The operation speed can be further finely controlled by using the measurement sensors 130. [

Fig. 4 is a schematic perspective view showing a state in which the distance indicator on Fig. 1 displays a distance on the semi-finished product.

Referring to FIG. 4, the length indicator 130 is configured to emit a photosensitive paint capable of recognizing the color paint or the distance measuring sensor more quickly and accurately at a predetermined length on the upper surface of the semi-finished product strip 5.

At this time, the distance indicator 120 is controlled by the control unit 110 to be controlled so as to emit a color line on the surface of the semi-finished product strip at a predetermined time interval.

The distance l3 between the distance indications is then determined by the respective length sensing sensors 140a, 140b, 140c installed on the first, second and third conveying conveyors 50, .

The semi-finished product strip 6 enters the first conveying conveyor 6 provided with the first distance detecting sensor 140a and the controller 130 displays the distance indications And then calculates the difference, that is, the actual shrinkage ratio, by comparing the distance between the distance indications applied by the length indicator at first.

The actual shrinkage rate calculated by the above method and the time of reaching the stacker 100 after passing through the die head 11 of the extruder 10 can be known through the speed of the extrusion line and the shrinkage rate (L) is calculated through Equation (4), it is possible to know an appropriate shrinkage rate until reaching the stacker 100. [

Therefore, if the measured actual shrinkage value is smaller than the calculated appropriate shrinkage value (less shrinkage), the speed of the withdrawal conveyor 20, the forced compression conveyor 30, and the cooling conveyor 40 located at the front end is reduced If, on the other hand, the actual shrinkage value is greater than the calculated shrinkage value (if there is more shrinkage), it increases their speed.

After the semi-finished product strip 5 passes through the cooling conveyor 60, when the second distance sensing sensor 140b enters the second conveying conveyor 70, the distance between the distance indications is also measured in the same way , And changes the speed of the cooling conveyor 60 located at the front end according to the difference between the actual shrinkage rate and the calculated appropriate shrinkage rate.

When the semi-finished product strip 5 reaches the third conveying conveyor 90, the distance between the distance indications is measured through the second distance detecting sensor 140c in the same manner as described above, The speed of the first conveying conveyor 70 and the second conveying conveyor 80 positioned at the front end is varied according to the difference between the shrinkage percentage and the shrinkage percentage.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but many variations and modifications may be made without departing from the spirit and scope of the invention. And it goes without saying that they belong to the scope of the present invention.

1 is a schematic view showing a tire semi-finished product extrusion control apparatus according to an embodiment of the present invention.

FIG. 2 is a view sequentially showing a tire semi-finished product extrusion control process according to an embodiment of the present invention.

3 is a schematic perspective view showing a width measurement state of a semi-finished product by the width detection sensor of FIG.

Fig. 4 is a schematic perspective view showing a state in which the distance indicator on Fig. 1 displays a distance on the semi-finished product.

Description of Main Drawings:

10: extruder 11: die head

20: draw-out conveyor 25, 35, 55, 75, 95: drive motor

30: forced contraction conveyor 40: first scale conveyor

45, 85: load cell 50: first conveying conveyor

60: cooling conveyor 70: second conveying conveyor

80: second scale conveyer 90: third conveying conveyor

100: Stacker 110: Controller

120: width detection sensor 130: distance indicator

140a, 140b, 140c:

Claims (7)

An extruder for extruding a rubber compound into a strip-shaped semi-finished product; A withdrawal conveyor provided continuously to the die head of the extruder; A width detection sensor installed on the drawing conveyor for measuring a width of the semi-finished product drawn out from the head of the compressor; A distance indicator installed at one side of the width detection sensor and displaying a distance on a semi-finished product drawn out from the extruder head at a preset time; A forced shrink conveyor provided continuously to the draw-out conveyor for shrinking the semi-finished product strip conveyed from the draw-out conveyor; A first scale conveyor provided continuously to the forced contraction conveyor for detecting the weight per unit length of the conveyed semi-finished product; A cooling conveyor installed continuously to the first scale conveyor and cooling the semi-finished product to be conveyed; A second scale conveyor provided continuously to the cooling conveyor and detecting a weight per unit length of the semi-finished product conveyed through the cooling conveyor; And A stacker installed continuously with the second scale conveyor to load the transported semi-finished products; A conveying conveyor arranged between the first scale conveyor, the cooling conveyor, the second scale conveyor, and the stackers, respectively, for conveying the semi-finished products; A distance detection sensor installed on each of the conveying conveyors to measure a distance between the distance indications displayed on the semi-finished product in the distance indicator; And Calculating a die expansion and contraction amount using the width value of the semi-finished product measured from the width detection sensor, Calculating a weight and shear rate per unit length of the semi-finished product measured through the first scale conveyor and the second scale conveyor, Calculating a shrinkage ratio at a specific time zone using the shrinkage amount, The extrusion speed calculated by using the shrinkage rate in the specific time period is calculated to calculate the extrusion speed by the extrusion conveyor, the steel material compression conveyor, the first scale conveyor, the cooling conveyor, the second scale conveyor, And a control unit for controlling the operation of the tire. The method of claim 1, The distance indicator comprises: Wherein the injection nozzle is a spray nozzle for spraying a color paint or a photosensitive paint. Measuring the width of a semi-finished product extruded in the form of a strip in an extruder head; Calculating die expansion using the semi-finished product width; Calculating a shrinkage ratio of the semi-finished product using the die swell; Calculating a shear rate; Calculating a shrinkage ratio at a specific time zone using the shrinkage ratio; And  Calculating an appropriate extrusion speed through the shrinkage rate in the specific time zone, and controlling an extrusion speed by comparing an appropriate extrusion speed with a current extrusion speed. 4. The method of claim 3, The die swell (DS)

The method comprising the steps of: (Where l1 is the width of the extrusion die head and l2 is the width of the extruded semi-finished product). 5. The method of claim 4, The shrinkage ratio (SR)

Semi-finished product extrusion control method for tire. (Where m is the characteristic value of the rubber compound that forms the semi-finished product). The method of claim 5, The shear rate (R)

The method comprising the steps of: Where d is the density of the extrudate, w is the width of the extrusion die head, H is the height of the extrusion die head, and? W is the shear stress), where Q is the extrusion volume (volumetric flow rate) The method of claim 6, The shrinkage ratio (L)

The method comprising the steps of: (Where k is a constant associated with the shear rate, t is the time, and a and b are constants dependent on the rubber compound properties).

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