JPH01163050A - Cutter device in tire grooving apparatus - Google Patents

Abstract

PURPOSE:To process a desired pattern groove to a tread surface, by mounting a contact member for allowing a cutter to protrude corresponding to the predetermined depth of a pattern groove and providing an elastic member energizing the cutter between a cutter clamp and a cutter support frame in a direction for bringing the same into contact with a tire to move the cutter by an elastic member apart from the movement of a cutter support apparatus so as to follow strain. CONSTITUTION:A tire 3 is mounted on a tire support stand 2 and positioned by moving a support truck on a rail 21 in an X-axis direction by an operation apparatus not shown in a drawing and moving the same on a rail 22 in a Y-axis direction. When the tread surface of the tire 3 is distorted and unevenness is generated from a reference surface shown by one-dot broken line, since a contact member 12 is brought into contact with the tread surface, a cutter clamp 86 allows an elastic member 9 to extend and contract corresponding to longitudinal vibration due to the unevenness to allow a cutter 10 to always move up and down so as to follow the tread surface and the depth of a groove to be formed is kept constant to prevent the generation of a shallow or deep part in the groove.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a grooving method in which a desired pattern of grooves is formed on the tread surface of a vulcanized or unvulcanized plain tire by numerically controlling a plurality of cutter operating axes. The invention relates to a cutter device.

(Prior art) Conventionally, when grooving the circumferential surface of a new or retreaded tire, the tire is rotatably supported perpendicularly to a support shaft, and the tire is grooved at least parallel to the tire support shaft in the vertical or longitudinal direction. A cutter holder is provided which is attached to a cutter support that moves in the direction, and a cutter that protrudes according to the depth of the pattern groove is fixedly attached to the cutter holder. It is designed to be moved relative to the tire surface.

(Problems to be Solved by the Invention) As described above, the cutter holder in the tire grooving device is fixedly attached to the cutter support base along with the cutter, and the entire cutter support base including the cutter is moved to increase the depth of the groove. is set, even if the cutter support is moved to the reference position corresponding to the amount of cutter protrusion, the groove depth may not be constant because the outer circumference of the tire is generally not a perfect circle and has irregularities. First, there is a problem in that the degree of wear of the grooves differs in the circumferential direction of the tires. Further, when the unevenness is caused not only by protrusions on the tire surface but also by distortion of the tire itself, the thickness from the groove bottom to the inner surface of the tire becomes thinner, which may impair the strength of the tire.

For example, as shown in Japanese Unexamined Patent Application Publication No. 62-74635, grooves can be adjusted by detecting irregularities on the tire surface and controlling the position of the cutter support according to the error from the reference position. Although it is possible to make the depth constant, there are drawbacks such as sensor installation, time lag in operation, and control of the cutter support, making the device complex and expensive.

(Means for Solving the Problems) The first aspect of the present invention is to maintain the groove depth constant regardless of the distortion of the tire tread surface using a simple device, and the cutter is attached to the cutter support device. A contact member is attached to the cutter, and the cutter is provided with a contact member that protrudes according to a predetermined depth of the pattern groove, and an elastic member that biases the cutter in the direction of contacting the tire is provided between the cutter clamp and the cutter support frame of the cutter support device. The cutter is supported by the elastic member so that the cutter moves in accordance with the distortion, independently of the movement of the cutter support device.

Further, the second invention is capable of raising the cutter position by raising the cutter support device itself and reducing the depth of the groove by providing a follow-up prevention means that prevents the cutter from following the cutter by the elastic member and the contact member. Wear indicator and 5
This makes it possible to form 0% wear marks and the like.

(Function) According to the first invention, since the contact member provided in the cutter support device moves together with the cutter, even if the tire has vertical runout, the cutter will follow it and always protrude from the contact member by the amount. A cutter cuts into the tire, grooving a groove of a certain depth.

Further, according to the second invention, the contact member can be fixed in a non-contact state from the tire surface, making it impossible for the cutter to follow the tire surface, and controlling the movement of the cutter support device in the tire contact/separation direction. Grooving is performed to a desired groove depth, and if necessary, the groove machining can be interrupted to create a portion without grooves.

(Example) In the example of the grooving device shown in FIG. 1, l is a base, 2 is a tire support stand installed on the base to support and rotate a tire 3, and 4 is a Y-axis direction parallel to the tire support axis. The support cart 5 moves in the vertical direction Z on the support cart 4.
A support base that moves in the axial direction; 6 is an arm support shaft protruding from the support base in the X-axis direction perpendicular to the Y-axis; 7 is a rotating arm fixed to this arm support shaft 6; A cutter support device 8 that moves in a direction perpendicular to the axis of the cutter 6 is attached.

Note that the present invention is not limited to the grooving device shown in this embodiment, but is applicable to any type of grooving device in which the movement of the cutter is numerically controlled by a plurality of cutter operation axes, and which automatically grooves a desired pattern groove in a fixed trajectory. Of course, the present invention can be applied to other devices.

As shown in detail in FIGS. 2 and 3, the cutter support device 8 includes a cutter support frame 82 provided on a column 81, and a cutter holder by inserting a tapered surface of an insulating base 83 into a tapered groove provided in the cutter support frame 82. A cutter clamp 86 is attached to the lower end of a support post 85 that passes through the cutter holder 84 via a bearing 87, so that the cutter clamp 86 can move in the axial direction of the support post 81. 9 is an elastic member such as a coil spring provided between the cutter holder 84 and the cutter clamp 86 surrounding the support post 85, and IO is a cutter.

In the cutter clamp 86, a clamp piece 102 is screwed to a clamp body 101 with a screw 103, and a cutter IO is clamped therebetween. 104 is an insulating spacer that insulates the clamp pieces 1.02 on both sides, and the power supply device l! Cutter! Heat O.

Reference numeral 12 denotes a contact member that is attached to the clamp body 101 via an adjustment rod 13 and comes into contact with the tread surface of the tire. It is made of a material with good slippage, such as a stainless steel plate, and is shaped into a sled according to the size of the cutter and the tread radius. As is clear from FIG. 4, the cutter lO is provided with a hole 14, from which the cutter lO protrudes, and the amount of this protrusion corresponds to the depth of the pattern groove by the amount of cutter protrusion from the adjustment rod 13 or the cutter holder. Then adjust it. For this adjustment, an elongated hole (not shown) in the axial direction is provided in the adjustment rod 13, and a tightening screw 131 inserted through the elongated hole is screwed into the clamp body 101.
Katta! The amount of protrusion of the clamp body 101 from the clamp body 101 may be adjusted to fix the tightening with the clamp piece 102.

Reference numeral 15 denotes follow-up prevention means that clamps the support post 85 that penetrates the cutter holder 84 and protrudes into the cutter support frame 82. For example, the support post 85 is sandwiched between clamping plates 152 from both sides by an electromagnetic device 151, and the cutter is cut by the elastic member 9. This is to prevent movement of the clamp 86. 16 is a stopper that prevents excessive movement of the support post.

The tire 3 is attached to the tire support stand 2, and the support cart 4 is moved along the rail 21 in the X-axis direction using an operating device (not shown).
The support stand 5 is moved on the rail 22 in the Y-axis direction for positioning, and the support stand 5 is moved to the screw shaft 2 by the motor 23 while rotating the tire 3.
4 in the Z-axis direction, and when the cutter support means 8 is lowered to the reference position toward the top of the tire 3 via the rotating arm 7, the cutter clamp 86 movably supported by the cutter holder 84 is moved by a coil spring. 9, the contact member 12 slides into contact with the tread surface of the tire 3,
A cutter lO protruding from the hole 14 of the contact member 12 is used to form a groove on the tread surface.

The cutter support device 8 is moved up and down by raising and lowering the support stand 5, but if it is supported so as to move up and down by an actuator 25 provided on the rotating arm 7, the cutter lO
The cutting amount of the cutter can be finely adjusted, and the cutting direction of the cutter (groove angle with respect to the tire circumferential direction) can also be adjusted by rotating the column 81 of the cutter support device 8 using the motor 26.

As shown in FIG. 5, if the tread surface of the tire 3 is distorted and has irregularities from the reference surface indicated by the dashed line, the contact member 12 will be in contact with the tread surface, causing vertical runout due to the uneven surface. According to the cutter clamp 86, the elastic member 9
The cutter lO is always moved up and down following the tread surface by expanding and contracting, and the depth of the groove to be grooved is kept constant, so that there are no shallow or deep grooves.

In addition, in order to warn of the safe wear limit and the time to replace the tire, a wear indicator 31 is provided on the bottom of the tread groove with a plurality of protrusions, for example, 1.6 mm thick and 30 mm long, in the circumferential direction, and a groove depth indicator 31 is provided. When providing a 50% wear mark 32 in which a plurality of protrusions each having a length of 20 mm and a thickness of 50% are provided in the circumferential direction, the support post 85 is gripped by the follow-up prevention means i5 at a predetermined rotation angle position, and the support post 85 is gripped by the elastic member 9. If the cutter clamp 86 is prevented from moving and the cutter support device 8 is raised from the reference position by the height of the marks 31 and 32 by the motor 23 or the actuator 25, the contact member 12 is fixed to the tire tread surface in a non-contact state. is,
A mark is formed by preventing the cutter from following the tire surface, rotating the tire by a predetermined angle in this state, and then releasing the follow-up preventing means 15 and returning the cutter to its reference position.

The structure of the cutter support device 8 is not limited to one in which a coil spring 9, which is an elastic member, is inserted between the cutter holder 84 and the cutter clamp 86, and as shown in FIGS. The support frame 82 may be connected to the support post 51, and the coil spring 9 may be wound around the support post as an elastic member. In this structure,
The cutter clamp 86 becomes independent of the support post 51,
The cutter 10 is set in the cutter clamp 86 in advance to form a cassette type, and the insulating base 83 of the cassetted cutter clamp can be attached to and detached from the tapered groove of the cutter holder 84, making it possible to efficiently replace the cutter. can. Also, follow-up prevention means! 5 can also be provided in the cutter holder 84, and in this embodiment, one end of a stopper rod 52 passing through the support post 51 is connected to an actuator 53 attached to the support post, and a friction plate 54 is provided at the other end. The actuator 53
Although the friction plate 54 is pressed against the friction surface 55 on the inner surface of the cutter holder to prevent movement by the elastic member 9, an electromagnetic brake may also be used.

Note that the elastic member 9 is not limited to the illustrated coil spring, but may be one using a pneumatic or hydraulic cylinder, and the contact member 12 is also formed in a separate structure divided on both sides of the cutter as shown in FIG. Alternatively, as shown in FIGS. 10 and 11, the cutter may be constructed with a pair of rollers 12a that transfer tire surfaces on both sides of the cutter. Further, the support post is not limited to the embodiment shown in the drawings, and may be one. The support post is fixed to the cutter holder side and slidably held on the cutter support frame side, and a follow-up prevention means is provided within the cutter support frame. You can also do that.

(Effects) As described above, the first invention includes: a cutter support device movably attached so that the cutter can be moved in the direction of contact with the tire; an elastic member that biases the cutter in the direction of contact with the tire; Equipped with a contact member that is attached to the cutter support device and brought into contact with the tire surface to regulate the cut depth of the cutter, so even if there is vertical runout due to unevenness or distortion on the tire tread surface, the cutter position always follows the vertical runout. The depth of grooving can be maintained constant by the cutter part protruding from the contact member, and a complicated mechanism and control system that detects the uneven surface of the tire with a separate sensor and corrects the cutter position is required. The second invention has the advantage of being able to be constructed with a simple structure without the need for a cutter.Furthermore, the second invention adds a follow-up prevention means that prevents the cutter from following the movement and fixedly supports the cutter support means and the cutter. By doing so, protrusions such as wear indicators and 50% wear marks can be easily and reliably formed on the bottom surface of the groove.

[Brief explanation of the drawing]

FIG. 1 is a side view showing an embodiment of the cutter device according to the present invention mounted on a grooving device, and FIG. 2 is a front view showing an embodiment of the cutter support device, partially in section. FIG. 3 is a side view thereof, FIG. 4 is a sectional view taken along line A-A in FIG. 2, and FIG. 5 is an explanatory diagram showing the state of grooving.
6 is a partial sectional view taken along the line B-B, FIG. 7 is a front view showing another embodiment of the cutter support device, FIG. 8 is a side view thereof, and FIG. 9 is another embodiment of the contact member. A diagram equivalent to Figure 4 showing an example,
FIG. 1O is a front view showing yet another embodiment of the contact member;
FIG. 11 is a side view showing the machining state. 2 is a tire support stand, 3 is a tire, 4 is a support cart, 5 is a support stand, 7 is a rotating arm, 8 is a cutter support device, 9 is an elastic member, 10 is a cutter, 11 is a power supply device, 12 and 12a are contact member, I5 is follow-up prevention means, 51 is support post, 5
2 is a stopper rod, 53 is an actuator, 54 is a friction plate, 55 is a friction surface, 81 is a column, 82 is a cutter support frame,
83 is an insulating base, 84 is a cutter holder, 85 is a support post, and 86 is a cutter clamp. 'Patent applicant
Sumitomo Rubber Industries, Ltd. Figure 1 Figure 2 Figure 3 Concave ILJ 14
1LIFig. 5 Fig. 10 Fig. 11

Claims (1)

[Scope of Claims] 1. In a tire grooving device that controls the movement of a cutter using a plurality of operating axes to form a desired pattern of grooves on the tire surface, a cutter support device to which the cutter is attached moves the cutter to the tire surface. The cutter is provided with an elastic member that movably supports the cutter in the direction of contact with and away from the tire and biases the cutter in the direction of contacting the tire, and a contact member that is attached with the cutter and contacts the tire surface to regulate the amount of cut of the cutter. A cutter device in a tire grooving device characterized by: 2. A cutter device in a tire grooving device according to claim 1, wherein the elastic member is a coil spring inserted between a cutter support frame and a cutter clamp of a cutter support device. 3. The cutter device in the tire grooving device according to claim 1 or 2, wherein the contact member is a sled that slides in contact with the tire surface. 4. The cutter device in the tire grooving device according to claim 1 or 2, wherein the contact member is a pair of rollers that roll in contact with the tire surface. 5. In a tire grooving device that controls the movement of a cutter using a plurality of operating axes to form a desired pattern of grooves on the tire surface, a cutter support device to which the cutter is attached moves the cutter in a direction toward and away from the tire. an elastic member that movably supports the cutter and biases the cutter in a direction to bring the cutter into contact with the tire; a contact member that is attached with the cutter and contacts the tire surface to regulate the cutting amount of the cutter; and the elastic member and the contact member. A cutter device for a tire grooving device, characterized in that the cutter device is provided with a follow-up prevention means for preventing the follow-up movement of the cutter.