Guide device

A guide device includes a guideway through which a steel wire passes when the steel wire is fed to a former. The guideway includes an inner surface. At least a portion of the inner surface includes a slit or recess at a position corresponding to a direction in which the steel wire is bent.

RELATED APPLICATIONS

The present invention is a U.S. National Stage under 35 USC 371 patent application, claiming priority to Serial No. PCT/JP2014/072426, filed on 27 Aug. 2014; the entirety of which is incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a guide device that includes a guideway through which a steel wire passes when the steel wire is fed to a former.

BACKGROUND ART

A guide device known in the art includes a guideway through which a steel wire passes when the steel wire is fed to a former to form a bead core, which is embedded in a bead of a tire.

Patent document 1 describes an example of a guide device that is located between a feeding roller, which feeds a rubber-coated steel wire, and a former, around which the steel wire is wound. The guide device includes a tetragonal housing and a guideway, which is located in the housing. The steel wire, which is fed by the feeding roller, passes through the guideway. The feeding of the steel wire passing through the guideway limits large sagging of the steel wire between the feeding roller and the former. The steel wire is shaped, or bent, in conformance with the diameter of a bead prior to being fed to the former by the feeding roller through the guide device. The distal end of the steel wire that has been fed to the former is clamped by a clamping device that is coupled to the former.

PRIOR ART DOCUMENT

Patent Document

SUMMARY OF THE INVENTION

Problems that are to be Solved by the Invention

While the steel wire is wound around the former, the steel wire is pulled by the former and the clamping device. Thus, when passing through the guideway, the steel wire extends straight, that is, the steel wire is not bent. After the steel wire is wound around the former a predetermined number of times, the steel wire is cut at the terminal end, that is, a portion of the steel wire that serves as the distal end of a steel wire that is next wound around the former. Consequently, the steel wire is not pulled by the former and the clamping device. This bends the steel wire in the guideway. When the steel wire is bent in the guideway, the surface of the steel wire may come into contact with the inner surface of the guideway. This applies resistance to the steel wire and twists the steel wire. When the steel wire is twisted as described above, the distal end of the steel wire is displaced from the desired position. Thus, the clamping device may fail to appropriately clamp the distal end of the steel wire.

It is an object of the present invention to provide a guide device that limits twisting of a steel wire in a guideway.

Means for Solving the Problems

To achieve the above object, a guide device of the present invention includes a guideway through which a steel wire passes when the steel wire is fed to a former. The guideway includes an inner surface. At least a portion of the inner surface includes a slit at a position corresponding to a direction in which the steel wire is bent.

In the above guide device, the steel wire does not contact the inner surface of the guideway at the portion including the slit. This limits twisting of the steel wire in the guideway.

To achieve the above object, a guide device of the present invention includes a guideway through which a steel wire passes. The steel wire is fed to a former. The guideway includes an inner surface. At least a portion of the inner surface includes a recess at a position corresponding to a direction in which the steel wire is bent.

The above guide device limits contact of the steel wire with the inner surface of the guideway at the portion including the recess. Thus, twisting of the steel wire is limited in the guideway.

Effect of the Invention

The guide device succeeds in limiting twisting of the steel wire in the guideway.

MODES FOR CARRYING OUT THE INVENTION

A bead core formation apparatus1according to one embodiment will now be described.

As shown inFIG. 1, the bead core formation apparatus1includes a guide device10, through which a rubber-coated steel wire W passes, a cutting device80, which cuts the steel wire W, and a winding device100, which forms a bead core by winding the steel wire W that is fed by the guide device10. The steel wire W is bent in conformance with the diameter of a bead prior to being fed to the guide device10by a feeding roller (not shown).

The guide device10includes a device body20and a steel wire passing portion30, through which the fed steel wire W passes.

As shown inFIG. 2, the device body20includes a first support plate21, to which the cutting device80is coupled, a second support plate22, to which the steel wire passing portion30is coupled, and an actuator23, which moves the second support plate22relative to the first support plate21. The second support plate22includes a guide22A, which is guided by a rail21A coupled to the first support plate21.

The steel wire passing portion30is connected to a piston rod70of a cylinder (not shown) by a connection shaft62. The piston rod70is coupled to the second support plate22. When the cylinder drives the piston rod70, the steel wire passing portion30is rotated about a rotation shaft61.

As shown inFIG. 1, the cutting device80includes an upper blade81, which is attached to be vertically movable relative to the first support plate21, and a lower blade82, which is fixed to the first support plate21. The upper blade81and the lower blade82cut the steel wire W at a cutting position XA after the steel wire W is wound around the winding device100a number of times in correspondence with the bead core to be formed.

The winding device100includes a former110, around which the fed steel wire W is wound, and a clamping device120, which is coupled to the former110to clamp the distal end of the steel wire W.

As shown inFIG. 2, the former110has a circumferential surface that includes a first winding groove111and a second winding groove112, which are arranged in an axial direction of the former110. The first winding groove111and the second winding groove112have different cross-sectional shapes in accordance with the shapes of bead cores to be formed. The steel wire W is wound around the first winding groove111or the second winding groove112to form the corresponding bead core.

As shown inFIG. 3, the steel wire passing portion30includes a body40, which includes a guideway41through which the steel wire W passes, and a base50, which is continuous with the body40.

The guideway41extends straight in a feeding direction of the steel wire W. The guideway41includes an inlet41A, which is tapered so that the inlet41A widens toward upstream from downstream in the feeding direction of the steel wire W.

As shown inFIGS. 3 and 4, the guideway41includes an outlet41B, to which a plurality (four in the embodiment) of miniature rollers43is coupled. Each miniature roller43is an example of a rotation element.

As shown inFIG. 3, a slit44extends through the body40between an upper surface42of the body40and an inner surface of the guideway41. The slit44extends in a direction in which the guideway41extends. The steel wire W is, for example, bent toward the upper surface42to be shaped in conformance with the bead diameter prior to being fed to the guideway41. Thus, to limit contact of the bent steel wire W with an inner portion of the guideway41, the slit44extends between the upper surface42and the inner surface of the guideway41at a position corresponding to the direction in which the steel wire W is bent.

The base50is continuous with an end of the body40located close to the inlet41A of the guideway41. The base50includes a first shaft hole51for the rotation shaft61(refer toFIG. 2), which serves as the rotation center of the steel wire passing portion30, and a second shaft hole52for the connection shaft62(refer toFIG. 2), which connects the piston rod70and the steel wire passing portion30. The first shaft hole51is located at a position downstream of the second shaft hole52in the feeding direction of the steel wire W.

The structure of the clamping device120will now be described with reference toFIGS. 5 to 7.

As shown inFIGS. 5 and 6, the clamping device120includes a clamp base130, which is coupled to the former110, a moving body140, which is moved relative to the clamp base130, and two moving legs170, which are connected to the moving body140.

The clamp base130includes a first base wall131and a second base wall132, which are used to hold the distal end of the fed steel wire W. As shown inFIG. 7, the first base wall131is provided corresponding to the first winding groove111. The second base wall132is provided corresponding to the second winding groove112.

The moving body140includes two rotation legs141, which are rotationally coupled to the clamp base130so that a portion of the clamp base130including the base walls131,132is held between the two rotation legs141. The rotation legs141are rotated about a rotation shaft142, which is supported by the clamp base130.

The moving body140includes a first clamp wall151, which is located between the two rotation legs141. The distal end of the steel wire W can be held between and clamped by the first clamp wall151and the first base wall131at a position corresponding to the first winding groove111(refer toFIG. 2).

The moving body140includes a second clamp wall161, which is located between the two rotation legs141. The distal end of the steel wire W can be held between and clamped by the second clamp wall161and the second base wall132at a position corresponding to the second winding groove112(refer toFIG. 2).

In the description hereafter, the position where the first clamp wall151or the second clamp wall161holds the distal end of the steel wire W, that is, the position of the moving body140when each clamp wall151,161is opposed to the corresponding base wall131,132, is referred to as the clamping position. Also, the position where the first clamp wall151and the second clamp wall161do not hold the distal end of the steel wire W, that is, the position of the moving body140when each clamp wall151,161is not opposed to the corresponding base wall131,132, is referred to as the non-clamping position.

Each moving leg170is connected to the corresponding rotation leg141by a connection shaft171so that the two rotation legs141are located between the two moving legs170. Each moving leg170includes a hole172. The holes172are rotationally connected to the distal end of an actuator (not shown).

The operation of the bead core formation apparatus1will now be described with reference toFIGS. 8 to 13. The former110is not shown inFIGS. 9 to 13.

First, the operation of the bead core formation apparatus1when the steel wire W is wound in the first winding groove111will be described.

When the piston rod70is retracted, the actuator23moves the second support plate22away from the clamping device120. In this state, the steel wire W, which is bent in a predetermined shape, is fed to pass through the guideway41of the steel wire passing portion30. The steel wire W is fed to a position where a predetermined length of the distal end of the steel wire W projects from the outlet41B of the guideway41.

Then, the retracted piston rod70is moved to project from the second support plate22, and the actuator23moves the second support plate22toward the clamping device120. Consequently, the steel wire passing portion30and the steel wire W, which is held by the device body20, are moved to the position shown inFIG. 9. This completes the positioning of the distal end of the steel wire W. At this time, as shown inFIG. 8with a steel wire W1indicated by a double-dashed line, the distal end of the steel wire W is located at a position separated from the first base wall131and the second base wall132.

After the distal end of the steel wire W is positioned in place in the feeding direction in this manner, the piston rod70is retracted. This rotates the steel wire passing portion30about the rotation shaft61as shown inFIG. 10. Consequently, the distal end of the steel wire W is moved to a position adjacent to the first base wall131as indicated by a solid line inFIG. 8.

After the distal end of the steel wire W is moved to the position adjacent to the first base wall131, the moving legs170are forced downward by the actuator (not shown). This moves the moving body140to the clamping position from the non-clamping position. Consequently, the first base wall131and the first clamp wall151clamp the steel wire W in between at the position corresponding to the first winding groove111(refer toFIG. 2). Also, the former110is increased in diameter.

As shown inFIG. 11, when the first base wall131and the first clamp wall151clamp the steel wire W, the actuator23moves the second support plate22away from the clamping device120. Thus, the outlet41B of the steel wire passing portion30is moved rearward from the cutting position XA, which is indicated by a single-dashed line.

Then, the former110is rotated to wind the steel wire W around the first winding groove111a predetermined number of times. After the steel wire W is wound in the first winding groove111, the cutting device80cuts the terminal end of the steel wire W. Also, the former110is reduced in diameter, and the moving body140is moved to the non-clamping position from the clamping position. This unclamps the distal end of the steel wire W from the clamping device120, and a bead core that conforms to the shape of the first winding groove111is obtained. When the cutting device80cuts the terminal end of the steel wire W, that is, a portion of the steel wire W serving as the distal end of a steel wire W that is next wound around the former110, the steel wire W is bent in the guideway41. The bent steel wire W enters the slit44, which is formed in the body40. Thus, the steel wire W does not contact the inner surface of the guideway41.

Next, the operation of the bead core formation apparatus1when the steel wire W is wound in the second winding groove112will be described.

After the distal end of the steel wire W is positioned in place in the feeding direction, the piston rod70is retracted from the position shown inFIG. 9to the position shown inFIG. 12. This rotates the steel wire passing portion30about the rotation shaft61. Consequently, as shown inFIG. 8with a steel wire W2indicated by a double-dashed line, the distal end of the steel wire W is moved to a position adjacent to the second base wall132.

After the distal end of the steel wire W is moved to the position adjacent to the second base wall132, the moving legs170are forced downward by the actuator (not shown). This moves the moving body140to the clamping position from the non-clamping position. Consequently, the second base wall132and the second clamp wall161clamp the steel wire W in between at the position corresponding to the second winding groove112(refer toFIG. 2). Also, the former110is increased in diameter.

As shown inFIG. 13, when the second base wall132and the second clamp wall161clamp the steel wire W, the actuator23moves the second support plate22away from the clamping device120. Thus, the outlet41B of the steel wire passing portion30is moved rearward from the cutting position XA, which is indicated by a single-dashed line.

Then, the former110is rotated to wind the steel wire W around the second winding groove112a predetermined number of times. After the steel wire W is wound in the second winding groove112, the cutting device80cuts the terminal end of the steel wire W. Also, the former110is reduced in diameter, and the moving body140is moved to the non-clamping position from the clamping position. This unclamps the distal end of the steel wire W from the clamping device120, and a bead core that conforms to the shape of the second winding groove112is obtained. When the cutting device80cuts the terminal end of the steel wire W, that is, a portion of the steel wire W serving as the distal end of a steel wire W that is next wound around the former110, the steel wire W is bent in the guideway41. The bent steel wire W enters the slit44, which is formed in the body40. Thus, the steel wire W does not contact the inner surface of the guideway41.

The embodiment has the advantages described below.

(1) The steel wire W does not contact the inner surface of the guideway41at the portion including the slit44. This limits twisting of the steel wire W in the guideway41.

(2) Since the twisting of the steel wire W is limited in the guideway41, displacement of the distal end of the steel wire W from the desired position is limited. This allows the clamping device120to appropriately clamp the distal end of the steel wire W.

(3) The slit44extends in the direction in which the guideway41extends. This further widens the portion of the inner surface of the guideway41that does not contact the steel wire W. Thus, when the steel wire W passes through the guideway41, the twisting is further limited.

(4) The inlet41A of the guideway41is tapered so that the inlet41A widens toward upstream from downstream in the feeding direction of the steel wire W. Thus, when the bent steel wire W is fed to the guideway41, contact of the steel wire W is limited with the inlet41A of the guideway41. This allows for easy entrance of the distal end of the steel wire W into the guideway41.

(5) The miniature rollers43are coupled to the outlet41B of the guideway41. This reduces friction generated when the steel wire W contacts the outlet41B of the guideway41. Thus, damages to the rubber coating of the steel wire W are limited.

(6) The base50is continuous with the end of the body40located close to the inlet41A of the guideway41. This extends the rotation radius of the steel wire passing portion30as compared to a structure in which the base50is continuous with the side surface of the body40. This increases the movement amount of the distal end of the steel wire W per unit of rotation angle.

The above embodiment may be modified as follows.

The inner surface of the guideway41may include a recess or indentation46in addition to the slit44or instead of the slit44, seeFIGS. 14 and 15. In this structure, when the steel wire W moves through the guideway41, contact of the steel wire W is limited with the inner surface of the guideway41at the portion including the recess or indentation46. This limits twisting of the steel wire W when passing through the guideway41. When the inner surface of the guideway41includes a recess or indentation46, it is preferred that the recess or indentation46extends in the direction in which the guideway41extends.

The slit44may extend between the inner surface of the guideway41and at least one of a side surface and a lower surface of the body40. More specifically, the slit44may be formed in any position of the guideway41corresponding to the direction in which the steel wire W is bent.

The outlet41B of the guideway41may be widened toward downstream from upstream in the feeding direction of the steel wire W. In this structure, when the steel wire W is bent in conformance with the bead diameter and fed to the guideway41, contact of the steel wire W is limited with the outlet41B of the guideway41. Thus, the distal end of the steel wire W easily exits from the guideway41.

When the outlet41B of the guideway41widens toward downstream from upstream in the feeding direction of the steel wire W, miniature rollers43may be coupled to the outlet41B.

The base50may be continuous with a portion of the body40corresponding to the side surface.

The first base wall131and the first clamp wall151may be omitted. Alternatively, the second base wall132and the second clamp wall161may be omitted.

DESCRIPTION OF REFERENCE CHARACTERS