JPH07115427B2 - Tire shaving device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tire shaving device.

Conventional technology Conventionally, tires with deep lug grooves formed in the tread part are
In order to prevent displacement of the ply due to excessive rubber flow during vulcanization, deep grooves similar to the pattern grooves of the product tire are formed in the tread portion at the stage of the unvulcanized green tire. However, even if the inside of the green tire is filled with a sufficient internal pressure, the radius of the tread surface is not uniform and the tread surface is uneven. For this reason, if the rubber of the tread portion is cut off one after another while the green tire is intermittently rotated by a cutter that constantly passes through a fixed trajectory, the depth of the deep groove formed will differ from groove to groove. There is.

In order to solve such a problem, there is a conventional method, for example, Japanese Patent Laid-Open No.
A shaving device for a tire as described in JP-A-59-215849 has been proposed. This one is provided with a blade tip that cuts off the rubber of the tire and a blade edge contact detection sensor that detects that the blade edge has contacted the tire at the tip of the cutter device, and when this sensor detects that the blade edge has contacted the tire. According to the program, the blade edge is moved to form a deep groove having a predetermined depth in the tire regardless of the unevenness of the tire radius.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, in such a tire shaving device, since both the blade edge and the sensor are provided together at the tip of the cutter device, the sensor malfunctions due to the vibration generated during rubber cutting. Or the sensor may be damaged by an excessive load.
Moreover, since the equipment must be condensed in one place,
There is also a problem that the structure becomes complicated.

Means for Solving the Problems Such problems include a moving base that moves along a plane including the axis of the green tire, and a cutter attached to the moving base, and the moving base is moved. While shaving the rubber of the tread portion of the green tire with a cutter to form a deep groove similar to a pattern groove in the tread portion of the tire, in the shaving device of the tire, the moving base is integrated with the moving base. Provided separately from the cutter for detecting the surface of the green tire when it comes into contact with the surface of the green tire,
The problem can be solved by providing a retracting unit that moves only the detector after the detector detects the surface of the green tire and retracts from the green tire.

Action First, the moving table, the detector, and the cutter are brought close to the green tire integrally, and the detector is brought into contact with the surface of the tread portion of the green tire. By this contact, the detector detects the position of the tread surface, and this position becomes the origin of the subsequent cutting operation. At this time, since the detector and the cutter are both attached to the moving base, the only member interposed between the detector and the cutter is the moving base, and as a result, the influence of mounting error or the like is almost eliminated. The cutter can be positioned at the origin without receiving it, and high-precision deep groove formation becomes possible. Then, when the moving table is moved while the detector is in contact with the tread surface in this way and the cutter tries to cut off the rubber of the tread portion to form a deep groove, the detector follows the moving table. It may be pressed against the surface of the tread portion and damaged. Therefore, prior to the rubber cutting, the retracting means is operated to retract only the detector from the green tire, thereby avoiding a direct adverse effect from the green tire due to contact between the detector and the green tire during cutting. Next, the movable table is moved with the detection position as a reference, and the rubber of the tread portion is cut off by a cutter to form a deep groove similar to the pattern groove.
In this way, the surface position of the green tire is detected for each cut, so that even if the radius of the green tire is uniform, the deep groove having the same depth can be formed.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

In FIGS. 1, 2, 3, and 4, reference numeral 1 is a shaving device, and a green tire T supported by a tire forming device (not shown) is provided in front of the shaving device 1. Is filled with a predetermined internal pressure. In addition, the shaving device 1 includes a frame 4
A pair of guide rails 11 parallel to the rotation axis of the green tire T are laid on the upper surface of the frame 4, and a horizontal moving plate 13 is slid on the guide rails 11 via linear slide bearings 12. It is movably supported. Also, a bracket is provided on the upper portion of the frame 4.
A motor 15 is attached via 14 and a pair of rollers 16 is rotatably supported on the frame 4 near both ends of the guide rail 11. A belt 17 connected to the moving plate 13 is stretched between these rollers 16, and the driving force of the motor 15 is transmitted to one roller 16 via a belt 18. As a result, the moving plate 13 can reciprocate along the rotation axis of the green tire T. Reference numeral 19 denotes a plurality of limit switches attached to the frame 4, and these limit switches 19 detect the position of the moving plate 13 and determine the start and end positions of the shaving work. A pair of guide rails 21 orthogonal to the guide rails 11 are laid on the moving plate 13, and a moving base 23 is slidably supported on the guide rails 21 via linear slide bearings 22. A screw shaft 24 extending in the radial direction of the green tire T in parallel with the guide rail 21 is rotatably supported on the moving plate 13 via a bearing 25. The screw shaft 24 is attached to the lower surface of the moving base 23. Screwed into the screw member 26. A motor 27 capable of rotating in the forward and reverse directions is installed on the upper surface of the moving plate 13, and a belt is provided between a pulley 29 fixed to a rotation shaft 28 of the motor 27 and a pulley 30 fixed to the screw shaft 24. 31
Have been passed over. When the screw shaft 24 rotates due to the forward and reverse rotations of the motor 27, the moving base 23 approaches and separates from the green tire T. In this way, the carriage 23 is driven by the motor 27.
Is moved toward and away from the green tire T, and is moved along with the moving plate 13 in the rotation axis direction of the green tire T by the operation of the motor 15. Therefore, the moving table 23 is moved along the plane including the rotation axis of the green tire T. It will move two-dimensionally. 33 is an encoder installed on the moving plate 13, and this encoder 33 has a belt 32.
The rotation of the screw shaft 24 is transmitted via the, and the radial position of the moving table 23 with respect to the green tire T is constantly detected. A vertical pin 36 is fixed to the front end of the moving base 23.
A holder 37 is rotatably supported by the. The holder 37 has a substantially U-shaped cutter 39 through an insulating material 38.
The cutter 39 is constantly supplied with electric power and heated to a predetermined temperature by Joule heat. Further, 41 is a cylinder connected to the movable table 23 via a bracket 40, and one end of a piston rod 42 of the cylinder 41 is connected to the other end of an arm 43 fixed to the holder 37 at one end. As a result, when the cylinder 41 operates, the cutter 39 swings about the pin 36 by 90 degrees. In FIGS. 1, 5 and 6, 46 is a movable table on the side of the cutter 39.
A detector installed separately from the cutter 39 on the 23, and the detector 46 detects the surface of the green tire T when it comes into contact with the surface. The detector 46 has two pairs of parallel links 47 whose lower ends are rotatably connected to the movable table 23, and at the upper ends of these parallel links 47, a horizontal movable body 48 which is parallel to the guide rail 21 is rotatable. Are linked to. The detector 46 can independently move relative to the moving table 23 by swinging the parallel link 47. A cylinder 50 as a retracting means is connected to the moving table 23 behind the movable body 48 via a bracket 49, and a tip of a piston rod 51 of the cylinder 50 is connected to the movable body 48. A pair of rods 52 parallel to the guide rails 21 are slidably supported via a sleeve 53 at the tip of the movable body 48.
A stopper plate 55 that stops the forward movement of the rod 52 by contacting the vertical surface 54 of the movable body 48 is fixed to the rear end of the movable body 48. The detection body 56 is fixed to the stopper plate 55,
In addition, the movable body 48 behind the detection body 56, the detection body
Proximity switch that detects when 56 has reached a specified position
57 is installed. A bracket 58 is fixed to the end of the rod 52, and a vertical pin is attached to the bracket 58.
A detection roller 60 that contacts the surface of the green tire T via 59 is rotatably supported. A spring 61 is provided around each rod 52 between the bracket 58 and the movable body 48, and the spring 61 connects the rod 52, the detection roller 60 and the stopper plate 55 to the vertical surface 54 of the green tire. Energize towards T.

Next, the operation of the embodiment of the present invention will be described.

First, the green tire T is molded by a tire molding device (not shown). At this time, the shaving apparatus 1 is retracted to a position that does not affect the molding operation. Next, when the molding operation of the green tire T is completed, the shaving device 1 is moved to immediately before the green tire T, and the lock pin 6 is inserted into the regulation hole 5 to position and fix the shaving device 1. Next, the motor 15 is operated and the belt 17 is run to move the moving plate.
13 is moved to near the equatorial plane of the green tire T. Then, when the limit switch 19 detects the moving plate 13, the moving plate 13 is stopped, and the cutting work starting point in the tire width direction is determined. Next, the piston rod 51 of the cylinder 50 is projected to rotate the parallel link 47 clockwise from the position shown by the solid line in FIG.
The detection roller 60 is integrally moved toward the surface of the tread portion of the green tire T. At this time, the rod 52 is biased by the spring 61 to project toward the green tire T, and the cutter 39 is parallel to the rotation axis of the green tire T as shown in FIG. The 60 is closer to the green tire T than the cutter 39. Next, the motor 27 is operated and the screw shaft is passed through the belt 31.
Rotate 24. As a result, the movable table 23 moves integrally with the detector 46 and the cutter 39 to approach the surface of the green tire T, and the detection roller 60 first contacts the surface of the tread portion. In this state, when the movable table 23 further advances, the rod
52 is pushed into the movable body 48 while compressing the spring 61, and the detection body 56 approaches the proximity switch 57. Then, when the detection body 56 reaches the predetermined position, the proximity switch 57
Is detected, the detection signal from the proximity switch 57 is sent to the motor 27 to stop the operation of the motor 27, and is also sent to the encoder 33 to clear the position memory of the encoder 33. In this way, the surface of the tread portion of the green tire T is detected by the detector 46, and the stop position of the moving table 23 at this time is the origin of the cutting operation for the green tire T. At this time, since the detector 46 and the cutter 39 are both attached to the moving table 23, the member interposed between the detector 46 and the cutter 39 is the moving table.
As a result, the cutter 39 can be positioned at the origin with almost no influence of mounting error or the like, and high-precision deep groove formation is possible. Then, when the moving table 23 is moved while the detector 46 is in contact with the surface of the tread portion and the rubber of the tread portion is to be cut off by the cutter 39 to form the deep groove, the detector 46 moves. There is a risk that it will be forcibly pressed against the surface of the tread portion following the table 23 and damaged. Therefore, prior to the rubber cutting, the cylinder 50 is actuated at the same time as the above-described origin detection to retract the piston rod 51, and only the detector 46 is moved to retract from the green tire T. As a result, even if the moving table 23 is moved during the cutting operation, it is possible to avoid direct interference in which the detector 46 is forcibly pressed against the green tire T. At this time, the rod 52
Is pressed by the spring 61 so that the stopper plate 55
Project until it touches. Next, when the motor 27 is operated again to rotate the screw shaft 24, the movable table 23 advances by a distance corresponding to the depth of the deep groove to be formed in the green tire T. At this time, the encoder 33 constantly detects the rotation of the screw shaft 24 and controls the moving distance of the moving table 23. Next, when the piston rod of the cylinder 41 is projected, the arm 43 rotates 90 degrees counterclockwise together with the cutter 39 from the position shown by the solid line in FIG. As a result, the cutter 39 bites into the tread portion of the green tire T. At this time, since the cutter 39 is heated by energization, the rubber in the tread portion can be easily cut. next,
When the motor 15 is operated and the belt 17 is run, the moving plate 13, the moving base 23, and the cutter 39 move leftward in FIG. 1 until they engage with the limit switch 19 as a unit. 39 cuts off the rubber of the tread portion of the green tire T to form a deep groove S having a predetermined depth and a predetermined width similar to the pattern groove in the tread portion on one side of the tire equatorial plane. When the excision work is completed in this way, the moving plate 13, the moving base 23, and the cutter 39 are returned to their initial positions by the operation of the motor 15, the motor 27, and the cylinder 41. The rubber cutting operation on the tread portion on the other side of the tire equatorial plane is performed by a shaving device (not shown) having the same configuration as described above. Next, after rotating the green tire T by a predetermined angle, the shaving device is operated again to cut off the rubber to form deep grooves S one after another in the circumferential direction of the tread portion.

EFFECTS OF THE INVENTION As described above, according to the present invention, the structure of the entire device is simplified, and the detector does not malfunction or break, and the deep groove is formed with high accuracy. You can also

[Brief description of drawings]

FIG. 1 is a plan view of relevant parts showing an embodiment of the present invention, FIG. 2 is a front view thereof, FIG. 3 is a right side view thereof, and FIG. 4 is a sectional view taken along the line I--I of FIG. 5 is a sectional view taken along the line II-II in FIG. 1, and FIG. 6 is a sectional view taken along the line III-III in FIG. 1 ... Shaving device 23 ... moving table, 39 ... cutter 46 ... detector

Claims (1)

[Claims] 1. A rubber for a tread portion of a green tire, comprising a moving base that moves along a plane including the axis of the green tire, and a cutter attached to the moving base, while the moving base is being moved by the cutter. In the shaving apparatus for a tire, which is formed by forming a deep groove similar to a pattern groove in the tread portion of the tire by cutting, the moving table is moved integrally with the moving table to contact the surface of the green tire. A detector for detecting the surface is provided separately from the cutter, and a retracting means is provided for retracting the green tire by moving only the detector after the detector detects the surface of the green tire. A characteristic tire shaving device.