Method and apparatus for supplying unvulcanized rubber sheets

Abstract

To provide a supply method and apparatus that can automatically and accurately center the leading edge of an unvulcanized rubber sheet to a target position while forming a dancer section in the middle of the supply path. [Solution] A centering conveyor 4 is placed between a rear conveyor 3 and a front conveyor 10 arranged sequentially in the supply path. The centering conveyor 4 has a transport surface with a support 5 that freely supports the sheet S in the planar direction, and guide bodies 7 arranged at both ends in the width direction of the transport surface. When the sheet S extending from the supply source 2 to the supply path is supported by the support 5 and passed between the guide bodies 7, the widthwise movement of each guide body 7 is controlled to center the leading edge of the sheet S to a target position on the front conveyor 10. After the leading edge of the sheet S has passed, the centering conveyor 4 is rotated downward by a predetermined angle around a pivot axis 9 located at its front end, thereby forming a dancer portion Sd on the sheet S between the rear conveyor 3 and the front conveyor 10.

Description

Technical Field

[0001] The present invention relates to a method and an apparatus for supplying an unvulcanized rubber sheet. More specifically, when forming a dancer part in the middle of a supply path and supplying the unvulcanized rubber sheet to a conveyance destination, the present invention relates to a method and an apparatus for supplying an unvulcanized rubber sheet that can automatically and accurately center the leading end of the unvulcanized rubber sheet at a target position for supply.

Background Art

[0002] In a manufacturing site of rubber products such as tires, for example, a long unvulcanized rubber sheet extruded by an extruder or the like is fed out from a pay-off device and supplied to a conveyance destination such as a forming drum for use. At the conveyance destination, predetermined processing such as forming the supplied unvulcanized rubber sheet into a cylindrical shape is performed. Therefore, it is necessary to center and supply the unvulcanized rubber sheet to the target position without meandering.

[0003] The unvulcanized rubber sheet may be supplied by forming a dancer part in the middle of the supply path. When supplying the unvulcanized rubber sheet to a conveyance destination through such a supply path, a device has been proposed that holds the leading end of the sheet fed out from the pay-off device and automatically transfers it to an introduction conveyor (see Patent Documents 1 and 2). The unvulcanized rubber sheets fed out from the pay-off device have some differences in the meandering condition for each individual and have variations. Therefore, in the conventionally proposed devices, there is a limit to improving the centering accuracy when transferring the held leading end of the sheet to the introduction conveyor. Therefore, there is room for improvement in automatically and accurately centering the leading end of the sheet at the target position when forming a dancer part in the middle of the supply path and supplying the unvulcanized rubber sheet to the conveyance destination.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

[0005] The object of the present invention is to provide a method and apparatus for supplying unvulcanized rubber sheets that can automatically and accurately center the leading edge of an unvulcanized rubber sheet to a target position when supplying the unvulcanized rubber sheet to a destination by forming a dancer section in the middle of the supply path. [Means for solving the problem]

[0006] To achieve the above objective, the present invention provides a method for supplying unvulcanized rubber sheets, in which, when supplying unvulcanized rubber sheets dispensed from a supply source to a destination via a rear conveyor and a front conveyor arranged sequentially along a supply path from the supply source to the destination, a dancer portion is formed on the unvulcanized rubber sheet along the supply path, and the leading edge of the unvulcanized rubber sheet is centered to a target position on the front conveyor, wherein a centering conveyor is arranged between the rear conveyor and the front conveyor, and the centering conveyor rotates up and down about a pivot axis located at its front end, and supports the unvulcanized rubber sheet freely in the planar direction. The conveying device has a conveying surface with a support body and guide bodies positioned at both ends of the conveying surface in the width direction, wherein each of the guide bodies is configured to be movable in the width direction on the conveying surface, and when the unvulcanized rubber sheet extending along the supply path is supported by the support body and passed between each of the guide bodies, the width direction movement of each of the guide bodies is controlled to center the leading edge to the target position, and after the leading edge has passed the centering conveyor, the centering conveyor is controlled to rotate downward by a predetermined angle around the pivot axis, thereby forming the dancer portion on the unvulcanized rubber sheet between the rear conveyor and the front conveyor.

[0007] The present invention provides a supply device for unvulcanized rubber sheets, comprising: a supply source for dispensing unvulcanized rubber sheets; a rear conveyor and a front conveyor arranged sequentially along a supply path from the supply source to a destination; and a control unit, wherein, under control by the control unit, a dancer portion is formed on the unvulcanized rubber sheet extending along the supply path between the rear conveyor and the front conveyor, and the leading edge of the unvulcanized rubber sheet is centered to a target position on the front conveyor, further comprising: a centering conveyor arranged between the rear conveyor and the front conveyor; and a drive roller that pulls the unvulcanized rubber sheet forward and extends it along the supply path, wherein the centering conveyor is centered on a pivot axis located at its front end. The conveying surface has a support that rotates up and down and freely supports the unvulcanized rubber sheet in the planar direction, and guide bodies are arranged at both ends of the conveying surface in the width direction, each of the guide bodies is configured to move in the width direction on the conveying surface, and when the unvulcanized rubber sheet is supported by the support and passes between each of the guide bodies, the leading edge is centered at the target position by controlling the width direction movement of each of the guide bodies, and after the leading edge has passed the centering conveyor, the centering conveyor is controlled to rotate downward by a predetermined angle around the rotation axis, thereby forming the dancer portion on the unvulcanized rubber sheet between the rear conveyor and the front conveyor. [Effects of the Invention]

[0008] According to the present invention, when the unvulcanized rubber sheet is supported by the support and passes between the respective guide bodies, the leading edge can be centered at the target position on the forward conveyor by controlling the widthwise movement of each guide body. Furthermore, after the leading edge has passed the centering conveyor, the centering conveyor can be controlled to rotate downward by a predetermined angle around the pivot axis, thereby forming the dancer portion on the unvulcanized rubber sheet between the rear conveyor and the forward conveyor. Therefore, while forming the dancer portion in the middle of the supply path, the leading edge of the unvulcanized sheet can be automatically and accurately centered at the target position and supplied to the destination. [Brief explanation of the drawing]

[0009] [Figure 1] This is an explanatory diagram illustrating an embodiment of an unvulcanized rubber sheet supply device in a plan view. [Figure 2] Figure 1 is an explanatory diagram illustrating the supply device in a side view. [Figure 3] This is an explanatory diagram illustrating the state in which an unvulcanized rubber sheet is being pulled forward by passing it through the centering conveyor shown in Figure 2. [Figure 4] Figure 3 is an explanatory diagram illustrating a supply device in a side view. [Figure 5] This is an explanatory diagram illustrating the state in which the centering conveyor shown in Figure 4 is rotated downward around its pivot axis to form a dancer section. [Figure 6] This is an explanatory diagram illustrating, in a plan view, a state in which the widthwise spacing between the pair of slide guides in Figure 5 has been reduced. [Figure 7] Figure 5 is an explanatory diagram illustrating the state after the excess portion at the tip of the unvulcanized rubber sheet has been cut off. [Modes for carrying out the invention]

[0010] The method and apparatus for supplying unvulcanized rubber sheets of the present invention will be described below based on the embodiments shown in the figures.

[0011] The embodiment of the unvulcanized rubber sheet supply device 1 illustrated in Figures 1 and 2 supplies the sheet material S (hereinafter referred to as sheet S) from a supply source 2 to a conveying destination such as a molding drum. Along the supply path, a dancer section Sd is formed on the sheet S, and the leading edge of the sheet S is automatically centered to a target position. The arrows X, Y, and Z in the figures indicate the front-to-back, width, and height directions of the supply device 1 (supply path), respectively, and are mutually orthogonal directions. The right side of the figure is the front of the supply device 1 (conveying destination side), and the left side is the rear of the supply device 1. The dashed line CL in the figure conveniently indicates the widthwise center of the sheet S and the supply path.

[0012] Examples of sheet S include various known types such as tire tread rubber and side rubber, which are made solely of unvulcanized rubber, and carcass material, which is made of unvulcanized rubber and reinforcing cords. Sheet S is not limited to components of tires, but may also be components of various rubber products such as conveyor belts and hoses. Because sheet S contains unvulcanized rubber, it is easily adhered to surfaces and easily deformed.

[0013] The supply device 1 includes a supply source 2 for dispensing sheets S, a rear conveyor 3 and a front conveyor 10 arranged sequentially along the supply path from the supply source 2 to the destination, and a control unit 14. The supply device 1 further includes a centering conveyor 4 positioned between the rear conveyor 3 and the front conveyor 10, and a drive roller 8 that pulls the sheets S forward and extends them along the supply path. In this embodiment, a position sensor 11 and a rotatable press roller 12 are positioned above the rear conveyor 3. A rotatable press roller 12 and a cutter section 13 are positioned above the front conveyor 10.

[0014] The control unit 14 controls the movement of the supply device 1. That is, the operation of the components of the supply device 1 is controlled by the control unit 14. The movement speed of the sheet S along the supply path is sequentially input to the control unit 14, and this movement speed is also controlled by the control unit 14. A known computer is used as the control unit 14.

[0015] In this embodiment, a supply reel is used as the supply source 2. The supply reel 2 is pivotally supported on a cart or the like so as to be rotatable about a support shaft 2a. A long sheet S is wound around the supply reel 2 with a liner interposed therebetween. By rotationally driving the supply reel 2 by driving means such as a motor, the sheet S is fed out. A winding shaft for winding the liner is arranged in parallel with the supply reel 2, and the liner peeled off from the fed-out sheet S is wound around the winding shaft. The supply source 2 is not limited to a supply reel, and various known mechanisms for feeding the sheet S into the supply path can be used.

[0016] The rear conveyor 3 has a number of free rollers 3a arranged at intervals in the front-rear direction. The sheet S fed out from the supply source 2 is placed on the free rollers 3a and moves forward while extending from the rear.

[0017] The position sensor 11 detects the leading end of the sheet S on the rear conveyor 3. Various known non-contact sensors such as a laser sensor can be employed for the position sensor 11. The detection signal from the position sensor 11 is input to the control unit 14.

[0018] The pressing roller 12 arranged above the rear conveyor 3 moves up and down under the control of the control unit 14. When the pressing roller 12 moves downward and approaches the rear conveyor 3, the sheet S placed on the rear conveyor 3 is pressed.

[0019] The front conveyor 10 has a number of free rollers 10a arranged at intervals in the front-rear direction. The sheet S moving forward is placed on the free rollers 10a and moves forward while extending from the rear.

[0020] The pressing roller 12 arranged above the front conveyor 10 moves up and down under the control of the control unit 14. When the pressing roller 12 moves downward and approaches the front conveyor 10, the sheet S placed on the front conveyor 10 is pressed.

[0021] The cutter unit 13 has a cutting blade that operates under the control of the control unit 14. The cutting blade moves downward and crosses the sheet S placed on the forward conveyor 10, thereby cutting the sheet S. Various known specifications that can cut the sheet S can be adopted for the cutter unit 13.

[0022] The centering conveyor 4 rotates up and down around a pivot axis 9 located at its front end. The centering conveyor 4 is controlled by the control unit 14 to rotate by a predetermined rotation angle D (angle D relative to the horizontal). For example, the centering conveyor 4 is rotated using a fluid cylinder or a servo motor. The rotation angle D is, for example, between 45° and 75°. The length of the centering conveyor 4 is, for example, between 300mm and 700mm.

[0023] The centering conveyor 4 has a conveying surface having support bodies 5 that freely support the sheet S in the planar direction (XY direction), and guide bodies 7 arranged at both ends in the width direction of the conveying surface. In this embodiment, numerous support bodies 5, each having a rotatable sphere protruding upward, are scattered on the conveying surface. The sheet S supported by the support bodies 5 can move in any direction in a plan view.

[0024] The guide body 7 uses free rollers that are erected in the height direction. At both ends in the width direction of the conveying surface, multiple free rollers 7 are erected and spaced apart in the front-to-back direction. The multiple free rollers 7 that are spaced apart in the front-to-back direction are installed on a slide frame 6. Therefore, this slide frame 6 is installed at one end and the other end in the width direction of the conveying surface. Each slide frame 6 moves in the width direction under the control of the control unit 14. That is, each free roller 7 located at both ends in the width direction of the conveying surface is configured to move in the width direction on the conveying surface.

[0025] The drive roller 8 is rotationally driven by a drive means such as a motor to pull the sheet S, which is fed out from the supply source 2, forward. In this embodiment, the drive roller 8 is located at the front end of the centering conveyor 4 and is configured to rotate around a pivot axis 9. The drive roller 8 can also be located further forward than the front end of the centering conveyor 4. That is, the drive roller 8 can be located between the front end of the centering conveyor 4 and the forward conveyor 10, or on the forward conveyor 10.

[0026] As illustrated in Figure 2, the conveying surfaces of the rear conveyor 3, centering conveyor 4, and front conveyor 10 are generally uniformly continuous in the conveying direction. However, these conveying surfaces may not only be uniformly continuous horizontally as in this embodiment, but may also be, for example, uniformly inclined downwards toward the destination, or uniformly inclined upwards toward the destination.

[0027] Next, an example of a procedure for supplying a sheet S to a destination while forming a dancer section Sd in the middle of the supply path of the sheet S using the supply device 1, and automatically centering the leading edge of the sheet S to a target position.

[0028] As illustrated in Figures 1 and 2, a new supply reel 2 is placed in the supply device 1, and the sheet S is unfurled by rotating this supply reel 2 around the pivot shaft 2a. The leading edge of the unfurled sheet S is placed on the rear conveyor 3 by a known mechanism.

[0029] As illustrated in Figures 3 and 4, the sheet S, with its leading edge placed on the rear conveyor 3, moves forward along the rear conveyor 3, and its leading edge is sequentially fed through the rear conveyor belt 3 and the centering conveyor 4 to the front conveyor 10. As a result, the sheet S extends from the rear conveyor belt 3 to the front conveyor 10.

[0030] On the rear conveyor belt 3, the downward-moved press roller 12 rolls while pressing against the sheet S. When the position sensor 11 detects the leading edge of the sheet 2 passing through the rear conveyor belt 3, the control unit 14 moves a pair of slide frames 6 in the width direction. More specifically, the pair of slide frames 6 (free rollers 7) are waiting with their widthwise spacing greater than the width of the sheet S. When the leading edge of the sheet 2 enters the centering conveyor 4, the widthwise spacing of the pair of slide frames 6 (free rollers 7) is reduced to a preset width. This preset width is slightly wider than the width of the sheet 2.

[0031] Both sides of the sheet S, supported by the support 5 and passing through the centering conveyor 4, are pressed by a pair of sliding frames 6 (free rollers 7) that have moved to a preset width dimension. This adjusts the widthwise position of the sheet S, centering it at the desired position. For example, the sheet S moves forward while being centered so that its widthwise center coincides with the widthwise center of the supply path.

[0032] As the leading edge of sheet 2 enters the forward conveyor 10, the downward-moved press roller 12 rolls while pressing down on sheet S. Also, sheet S, which is placed on the drive roller 8, is pulled forward by the rotationally driven drive roller 8. On the forward conveyor 10, the leading edge of sheet S is centered at the target position.

[0033] After the leading edge of the sheet S has passed through the centering conveyor 4, the centering conveyor 4 is rotated downward by a predetermined angle D around the pivot axis 9, as illustrated in Figure 5. As a result, the conveying surface of the centering conveyor 4 becomes inclined at a predetermined angle D. When the centering conveyor 4 rotates downward, the sheet S placed on the conveying surface of the centering conveyor 4 temporarily floats in the air, separated from the conveying surface. At this time, if the widthwise spacing of the pair of slide frames 6 (free rollers 7) is maintained at the preset width dimension described above, there is a risk that the sheet S extending along the centering conveyor 4 may be subjected to unnecessary force by the pair of slide frames 6 (free rollers 7) rotating downward, causing deformation or displacement.

[0034] Therefore, in order to avoid such problems, before rotating the centering conveyor 4 downwards, the pair of slide frames 6 (free rollers 7) are moved in the width direction to increase their widthwise spacing. The widthwise spacing at which the pair of slide frames 6 (free rollers 7) do not come into contact with the sheet S extending from the centering conveyor 4 when the centering conveyor 4 is rotated downwards is determined in advance, and the pair of slide frames 6 (free rollers 7) are moved until this predetermined widthwise spacing is achieved, thereby increasing their widthwise spacing.

[0035] The leading edge of the sheet S is held between the forward conveyor 10 and the retaining roller 12. The rotational drive of the drive roller 8 is stopped to lock the retaining roller 12 above the forward conveyor 10 so that it does not rotate. Alternatively, instead of locking the rotation of the retaining roller 12, the pulling speed of the sheet S by the drive roller 8 is made slower than the feeding speed of the sheet S by the supply reel 2, so that the drive roller 8 applies a forward driving force to the sheet S. This prevents the sheet S from sliding backward even when the centering conveyor 4 is rotated downward.

[0036] In this state, as the sheet S continues to be fed from the supply reel 2, slack is created in the sheet S between the rear conveyor 3 and the front conveyor 10, and the sheet S is placed again on the inclined conveying surface of the centering conveyor 4. As a result, as illustrated in Figure 5, a dancer section Sd is formed between the rear conveyor 3 and the front conveyor 10, with the sheet S hanging downwards.

[0037] The amount of sagging of the sheet S in the dancer section Sd changes according to the pulling speed of the sheet S by the drive roller 8 and the feeding speed of the sheet S by the supply reel 2, and is set appropriately according to the processing time (processing time) of the sheet S at the destination. By making the pulling speed of the sheet S by the drive roller 8 and the feeding speed of the sheet S by the supply reel 2 the same, a constant amount of sagging of the sheet S is maintained.

[0038] After the dancer section Sd is formed, as illustrated in Figure 6, the pair of slide frames 6 (free rollers 7), which are widened in the width direction, are moved in the width direction to reduce the width direction distance again to a size slightly wider than the width of the sheet S. This presses both sides of the sheet S, which is supported by the support 5 on the inclined conveying surface of the centering conveyor 4 and passing through the centering conveyor 4, against the pair of slide frames 6 (free rollers 7), centering the sheet S to the desired position. For example, the sheet S is centered so that its width direction center coincides with the width direction center of the supply path.

[0039] Subsequently, the sheet S extending along the supply path is centered at the target position and pulled forward by the drive roller 8 to be supplied to the destination. At the destination, for example, the sheet S is cut to an appropriate length and wound onto a forming drum to be formed into a cylindrical shape. The destination is not limited to a forming drum; it may also be a winding drum, and the sheet S supplied to the winding drum is wound onto the winding drum and stored for a predetermined period.

[0040] Each sheet S unloaded from the supply reel 2 has a different degree of meandering. In this embodiment, as described above, when the sheet S is supported by the support 5 on the centering conveyor 4 and passes between a pair of free rollers 7 spaced apart in the width direction, the widthwise movement of the pair of free rollers 7 is controlled. Therefore, even if the sheets S have different degrees of meandering, the leading edge of the sheet S can be automatically and accurately centered at the target position on the forward conveyor 10.

[0041] Furthermore, after the leading edge of the sheet S passes through the centering conveyor 4, the centering conveyor 4 is controlled to rotate downward by a predetermined angle D around the pivot axis 9, thereby forming a dancer section Sd between the rear conveyor 3 and the front conveyor 10. Even with the formation of this dancer section Sd, the widthwise displacement of the sheet S is suppressed by the pair of free rollers 7 of the centering conveyor 4, thus maintaining the centering accuracy relative to the sheet S.

[0042] Therefore, in this embodiment, the process of extending the leading edge of the sheet S unwound from the supply reel 2 to the forward conveyor 10 and centering it at the target position can be automated. Since this process is required each time the supply reel 2 is switched, automating it reduces the workload on the worker and also contributes to improved work efficiency by allowing the process to be carried out smoothly.

[0043] As described above, the centering conveyor 4 adjusts the widthwise position of the sheet S while moving it forward between the rear conveyor 3 and the front conveyor 10. Since the sheet S does not move substantially in the widthwise direction on the rear conveyor 3 and the front conveyor 10, if the length of the centering conveyor 4 is too short, there is a risk that the sheet S will be sharply bent in the widthwise direction when centering it to the target position, causing unnecessary deformation. On the other hand, if the length of the centering conveyor 4 is too long, it will be disadvantageous for miniaturizing the supply device 1. Therefore, the length of the centering conveyor 4 should be, for example, between 300 mm and 700 mm.

[0044] Near the leading edge of the sheet S unwound from the supply reel 2, phenomena such as the sheet becoming thinner than specified due to shrinkage over time are sometimes observed. Therefore, in this embodiment, as illustrated in Figure 7, a predetermined length from the leading edge of the sheet S is considered an excess portion, and this excess portion is cut off by the cutter section 13 on the forward conveyor 10. Then, the sheet S with the excess portion cut off and a new leading edge formed is supplied to the destination.

[0045] If the sheet S is formed solely of unvulcanized rubber, the degree of meandering will be greater compared to a sheet S in which reinforcing materials are embedded, and the variation in the degree of meandering from one sheet S to another will also be greater. For this reason, the above-described embodiment is particularly preferable to apply to a sheet S formed solely of unvulcanized rubber.

[0046] The embodiments described above are not limited to pneumatic tires, but can be applied to the manufacturing processes of various other types of tires and other rubber products. [Explanation of symbols]

[0047] 1 Feeding device 2. Supply reel (supply source) 2a spindle 3 Rear conveyor 3a Free Roller 4 Centering conveyor 5 Support 6 Slide Frames 7 Guide body (free roller) 8 drive rollers 9 rotational axes 10. Forward conveyor 10a Free Roller 11 Position Sensor 12 Pressing roller 13 Cutter section 14 Control Unit S Unvulcanized rubber sheet Sd Dancer Club

Claims

1. In a method for supplying unvulcanized rubber sheets, in which an unvulcanized rubber sheet unwound from a supply source is supplied to a destination via a rear conveyor and a front conveyor arranged sequentially along a supply path from the supply source to the destination, a dancer portion is formed on the unvulcanized rubber sheet along the supply path, and the leading edge of the unvulcanized rubber sheet is centered to a target position on the front conveyor, A centering conveyor is positioned between the rear conveyor and the front conveyor, and the centering conveyor rotates vertically around a pivot axis located at its front end, and has a conveying surface having a support that freely supports the unvulcanized rubber sheet in the planar direction, and guide bodies positioned at both ends of the conveying surface in the width direction, with each of the guide bodies configured to be movable in the width direction on the conveying surface. When the unvulcanized rubber sheet extending along the supply path is supported by the support and passed between each of the guide bodies, the leading edge is centered at the target position by controlling the widthwise movement of each of the guide bodies. A method for supplying an unvulcanized rubber sheet, wherein after the leading edge has passed the centering conveyor, the centering conveyor is controlled to rotate downward by a predetermined angle around the pivot axis, thereby forming the dancer portion on the unvulcanized rubber sheet between the rear conveyor and the front conveyor.

2. The method for supplying an unvulcanized rubber sheet according to claim 1, wherein a predetermined length of excess portion from the leading edge of the unvulcanized rubber sheet is cut off by a cutter on the forward conveyor, and the unvulcanized rubber sheet with a new leading edge is supplied to the destination.

3. The method for supplying an unvulcanized rubber sheet according to claim 1 or 2, wherein the unvulcanized rubber sheet is formed solely of unvulcanized rubber.

4. The system comprises a supply source for dispensing unvulcanized rubber sheets, a rear conveyor and a front conveyor arranged sequentially along the supply path from the supply source to the destination, and a control unit. In an unvulcanized rubber sheet supply device in which, under control by the control unit, a dancer portion is formed on the unvulcanized rubber sheet extending along the supply path between the rear conveyor and the front conveyor, and the leading edge of the unvulcanized rubber sheet is centered to a target position on the front conveyor, The system includes a centering conveyor positioned between the rear conveyor and the front conveyor, and a drive roller that pulls the unvulcanized rubber sheet forward and extends it along the supply path. The centering conveyor rotates vertically around a pivot axis located at its front end and has a conveying surface having a support that freely supports the unvulcanized rubber sheet in the planar direction, and guide bodies located at both ends of the conveying surface in the width direction, with each of the guide bodies being configured to move in the width direction on the conveying surface. As the unvulcanized rubber sheet is supported by the support and passes between each of the guide bodies, the leading edge is centered at the target position by controlling the widthwise movement of each of the guide bodies. A vulcanized rubber sheet supply device in which, after the leading edge passes the centering conveyor, the centering conveyor is controlled to rotate downward by a predetermined angle around the pivot axis, thereby forming the dancer portion on the unvulcanized rubber sheet between the rear conveyor and the front conveyor.

5. The supply device for unvulcanized rubber sheets according to claim 4, wherein the length of the centering conveyor is set to 300 mm or more and 700 mm or less.

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