JPH0474179B2 - - Google Patents

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 present 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 and in the vertical or longitudinal direction. A cutter boulder is attached to a cutter support stand to be moved.A cutter that protrudes according to the depth of the pattern groove is attached and fixed to this cutter holder.The cutter support is placed on the tire surface so that the cutter has the desired depth of cut. It is made to move against the other side.

(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 together with the cutter, and the entire cutter support base including the cutter is moved to increase the depth of the groove. is set, so even if the cutter support is moved to the reference position corresponding to the protrusion amount of the cutter, 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 varies in the circumferential direction of a single tire. 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 Patent Application Laid-Open 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. between the cutter clamp of the cutter support device and the cutter support frame;
An elastic member is provided to bias the cutter in a direction to bring it into contact with the tire, and the cutter is supported so as to follow the strain and move by the elastic member independently of movement of the cutter support device.

Further, the second invention provides a follow-up prevention means for preventing the cutter from following the cutter by the elastic member and the contact member, so that the cutter position is raised by raising the cutter support device itself, and the depth of the groove is made shallower. This makes it possible to form wear indicators, 50% wear marks, etc.

(Function) According to the first invention, since the contact member provided on the cutter support device moves together with the cutter, even if the tire has vertical runout, the cutter follows it and always cuts by the amount that protrudes from the contact member. is cut into the tire to form grooves 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 direction of contact with and away from the tire. The groove is grooved to a desired groove depth, and if necessary, the groove machining can be interrupted to create a part without grooves.

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

Note that the present invention is not limited to the grooving device shown in this embodiment, but the movement of the cutter is numerically controlled by a plurality of cutter operation axes, and a desired pattern groove is automatically grooved in a fixed trajectory. Of course, it can be applied to all 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 84 by inserting a tapered surface of an insulating base 83 into a tapered groove provided in the cutter support frame 82. are removably fitted and held, and a cutter clamp 86 is attached to the lower end of a support post 85 that passes through this cutter holder 84 via a bearing 87.
The cutter clamp 86 is movable in the axial direction of the support column 81. 9 is the cutter holder 84
An elastic member such as a coil spring is provided between the support post 85 and the cutter clamp 86, and 10 is a cutter.

In the cutter clamp 86, a clamp piece 102 is screwed to a clamp body 101 with a screw 103, and the cutter 10 is clamped therebetween. Insulating spacers 104 insulate the clamp pieces 102 on both sides, and the cutter 10 is heated by the power supply device 11.

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 formed into a sled shape of a size according to the size of the cutter and the tread radius. As is clear from FIG. 4, it is provided with a hole 14.
The cutter 10 is made to protrude from the cutter, and the amount of protrusion D is adjusted according to the depth of the pattern groove by the amount of protrusion of the cutter from the adjustment rod 13 or the cutter holder. 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 this elongated hole is screwed into the clamp body 101. The amount of protrusion may be adjusted and the clamp piece 102 may be tightened and fixed.

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

The tire 3 is attached to the tire support base 2, and the support cart 4 is moved on the rail 21 in the X-axis direction and on the rail 22 in the Y-axis direction to position it, and while the tire 3 is rotated. When the support stand 5 is lowered in the Z-axis direction by the motor 23 and the screw shaft 24, and 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 holder 84 is movably moved. The supported cutter clamp 86 is pushed out by the coil spring 9, and the contact member 12 slides into contact with the tread surface of the tire 3, and the cutter 10 protruding from the hole 14 of the contact member 12 forms a groove on the tread surface. .

The cutter support device 8 is moved up and down by the lifting and lowering of the support base 5, but if it is supported so as to move up and down by an actuator 25 provided on the rotation arm 7, the cutting amount of the cutter 10 can be controlled. Fine adjustments can be made, 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 uneven from the reference surface shown by the dashed line, the contact member 12 will be in contact with the tread surface, causing vertical runout due to the uneven surface. Accordingly, the cutter clamp 86 expands and contracts the elastic member 9 to move the cutter 10 up and down while always following the tread surface, thereby keeping the depth of the groove to be grooved constant and preventing the formation of shallow or deep grooves. do not have.

In addition, in order to warn of safe wear limits and when it is time to replace the tire, the bottom of the tread groove should be marked with a
Wear indicator 31 has multiple protrusions of 1.6 mm and length of 30 mm in the circumferential direction, and 50% has multiple protrusions of 220 mm in length with a thickness of 50% of the groove depth in the circumferential direction.
When the wear mark 32 is provided, the support post 85 is gripped by the follow-up prevention means 15 at a predetermined rotation angle position, the movement of the cutter clamp 86 by the elastic member 9 is prevented, and the cutter support device 8 is stopped by the motor 23 or the actuator 25. If you raise it by the height of marks 31 and 32 from the reference position,
The contact member 12 is fixed to the tire tread surface in a non-contact state to prevent the cutter from following the tire surface, and after rotating the tire by a predetermined angle in this state, the following prevention means 15 is released and the cutter is returned to the reference position. As a result, a mark is formed.

The structure of the cutter support device 8 is that the cutter holder 84
In addition to inserting a coil spring 9, which is an elastic member, between the cutter clamp 86 and the cutter clamp 86, the cutter holder 84 and the cutter support frame 82 can be connected by the support post 51 as shown in FIGS. 7 and 8. However, a coil spring 9 may be wound around this support post as an elastic member. In this structure, the cutter clamp 86 is 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 detachably attached to the tapered groove of the cutter holder 84.
Cutters can be exchanged efficiently. Further, the follow-up prevention means 15 can also be provided in the cutter holder 84, and in this embodiment the support post 5
One end of a stopper rod 52 penetrating across the cutter holder is connected to an actuator 53 attached to a support post, a friction plate 54 is provided at the other end, and the actuator 53 presses the friction plate 54 against a friction surface 55 on the inner surface of the cutter holder. Although the elastic member 9 is used to prevent movement, an electromagnetic brake may also be used.

Note that the elastic member 9 is not limited to the illustrated coil spring, but may also 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 rolling on 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 contacting the tire, It is equipped with a contact member that is attached to the cutter support device and brought into contact with the tire surface to regulate the amount of cut of the cutter.
Even if there is vertical deflection due to unevenness or distortion on the tire ret surface, the cutter position can always be moved to follow the longitudinal deflection, and the depth of the grooving can be maintained constant by the cutter portion protruding from the contact member. There is no need for a complicated mechanism or control that detects the uneven surface of the tire using a separate sensor and corrects the cutter position, and it has the advantage of being able to be configured with a simple structure.
In addition, the second invention prevents the following movement of the cutter and by adding a follow-up prevention means that fixedly supports the cutter support means and the cutter, it is possible to mark the bottom of the groove with a wear indicator, a 50% wear mark, etc. Protrusions can be formed easily and reliably.

[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, FIG. 4 is a sectional view taken along line A-A in FIG. 2, FIG. 5 is an explanatory diagram showing the state of grooving, and FIG. 6 is 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 a partial sectional view taken along line B; FIG. 4 shows another embodiment of the contact member. The corresponding drawings, FIG. 10 is a front view showing still another embodiment of the contact member, and FIG. 11 is a side view thereof showing a processed 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 A contact member, 15 is a following prevention means, 51 is a support post, 52 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
84 is an insulating base, 84 is a cutter holder, 85 is a support post, and 86 is a cutter clamp.

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. The tire is equipped with an elastic member that movably supports the cutter in the direction of contact and separation from the tire and biases the cutter in the direction of contacting the tire, and a contact member that is attached together 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. The cutter device in a tire grooving device according to claim 1, wherein the elastic member is a coil spring inserted between the cutter support frame and the cutter clamp of the 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 cutting 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 together with the cutter and contacts the tire surface to regulate the amount of cut of the cutter; and the elastic member and the contact member. 1. 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.