Mehtod of assembling stud pin of stud tire

Abstract

The present invention provides a method for assembling stud pins of a stud tire, which enables efficient quality control by making the height of the stud pin protruding outward uniform when assembling the stud pin into the stud hole, and simultaneously enables rapid determination of the stud pin assembly status due to internal defects in the stud hole. According to the present invention, when assembling a stud pin into a stud hole, if a vertically rising force is applied to the stud pin when the header rises after inserting the stud pin, the stud pin is assembled in a state where the anti-detachment plate of the stud pin is in contact with the upper inner surface of the stud hole, so the stud pin can be assembled to have a uniform height relative to the tire tread, and at the same time, the fastening state of the stud pin due to defects in the inner surface of the stud hole can be immediately determined, thereby increasing the efficiency of quality control of studded tires.

Description

Technology Field

[0001] The present invention relates to a method for assembling stud pins of a stud tire. Background Technology

[0003] In regions with heavy snowfall during the winter, snow accumulated on roads becomes compacted by vehicles driving on them, and freezes at night, leading to frequent accidents caused by vehicles skidding on snowy and icy roads. Consequently, stud tires are being developed to enable safe driving without slipping on snow-covered, compacted, and icy roads.

[0005] A stud tire is a tire equipped with stud pins, which are small pins inserted into stud holes formed in the tread. On snowy or slippery roads, the stud pins act like spikes to grip the snow and ice formed on the road surface, helping the vehicle to drive safely without slipping.

[0007] Currently, stud pins are inserted into stud holes formed in the tire treads manually or semi-automatically as a method for manufacturing studded tires. However, it is difficult to insert stud pins consistently due to this manual process, which leads to decreased productivity caused by product defects and losses resulting from the disposal of damaged tires. Therefore, an automated stud insertion device that automatically fastens stud pins to the tire treads is being developed to reduce labor costs and improve productivity.

[0009] As prior art related to the present invention, Korean Published Patent Application No. 10-2019-0008694 discloses a studded tire comprising a recess provided on the tread surface and a stud pin inserted into the recess, wherein the stud pin comprises a head portion protruding outwardly from the tread surface, a body portion connected to the head portion and located within the recess, and a flange portion disposed on the opposite side of the head portion with the body portion in between, and having a concave portion concave with respect to the bottom surface. However, the above prior art discloses only the structure of the stud pin to prevent the stud pin from detaching from the stud hole during driving, and does not disclose a configuration for maintaining a uniform protrusion height of the stud pin assembled on a rubber tire tread or for solving assembly defects of the stud pin caused by internal defects in the stud hole.

[0011] The stud insertion device is configured such that after the header of the insertion device is aligned with the upper part of the stud hole, the header is lowered so that the gripper is inserted into the stud hole, and as the stud pin inserted into the insertion device descends as the pusher descends, the gripper expands so that the stud pin is inserted into the stud hole. However, there is a problem in that when the stud pin is assembled on a tire tread made of rubber material, the protrusion height of the stud pin is not uniform, making quality control difficult, or it is difficult to determine whether the stud pin is assembled incorrectly due to defects inside the stud hole. Prior art literature

[0013] 1. Korean Patent Publication No. 10-2019-0008694 The problem to be solved

[0014] The present invention has been devised to solve the aforementioned problems, and the objective of the present invention is to provide a method for assembling stud pins of a stud tire that enables efficient quality control by making the height of the stud pin protruding outward uniform when assembling the stud pin into the stud hole, and at the same time allows for rapid determination of the stud pin assembly status due to internal defects in the stud hole. means of solving the problem

[0016] To solve the above problem, a stud pin assembly method for a stud tire, which is an embodiment of the present invention, may include the steps of: transporting the header of a stud pin insertion device to the upper part of a stud hole and then lowering the header; lowering a pusher to insert a stud pin into a stud hole; and raising the header to apply a vertical force to the stud pin.

[0018] According to one embodiment of the present invention, the step of raising the header to apply vertical force to the stud pin is characterized in that a protrusion formed at the bottom of the gripper and a locking projection formed on the stud pin are in close contact by an elastic ring.

[0020] According to one embodiment of the present invention, the retaining projection of the stud pin is characterized by having an inclined surface such that when the stud pin can no longer rise due to contact between the anti-detachment plate of the stud pin and the upper inner surface of the stud hole, the projection slides out of the retaining projection. Effects of the invention

[0022] According to the present invention as described above, when a stud pin is assembled into a stud hole by means of a stud pin insertion device, the stud pin is assembled with a pre-set protrusion height based on the tire tread surface, so that after assembly, it is not necessary to manually match the height of stud pins having various protrusion heights, thereby improving work efficiency and ensuring the production quality of the stud tire.

[0023] In addition, the stud pin assembly method allows for the verification of internal defects in the stud holes formed within the tire tread during assembly, thereby enabling the immediate determination of stud pin assembly defects caused by internal stud hole defects and increasing the efficiency of tire production quality control. Brief explanation of the drawing

[0025] FIG. 1 is a process flowchart for explaining a stud pin assembly method of a stud tire according to one embodiment of the present invention. FIGS. 2a and 2c are drawings for explaining the header of a stud pin assembly device that automatically inserts a stud pin according to an embodiment of the present invention. FIG. 3 is a drawing for explaining a gripper of a stud pin assembly device according to one embodiment of the present invention. FIG. 4 is a schematic diagram illustrating stud assembly defects in internal stud holes according to one embodiment of the present invention. Specific details for implementing the invention

[0026] The following detailed description is merely illustrative and illustrates embodiments of the present invention. Furthermore, the principles and concepts of the present invention are provided for the purpose of being most useful and easy to explain.

[0027] Accordingly, it is not intended to provide a structure more detailed than necessary for a basic understanding of the present invention, and various forms in which the invention may be implemented in substance are illustrated through the drawings by those skilled in the art.

[0029] The configuration and operation of a preferred embodiment of the present invention will be described in detail below with reference to the attached drawings.

[0031] FIG. 1 is a process flowchart for explaining a stud pin assembly method of a stud tire according to one embodiment of the present invention.

[0032] A stud pin insertion device is generally provided to automatically assemble stud pins into stud holes formed in tire treads. The stud pin insertion device includes an x, y, and z transfer stage for guiding the transfer of a header receiving a stud pin into the upper part of the stud hole, an air injection unit for transmitting air pressure to lower a pusher located inside the header transferred to the upper part of the stud hole, and a control unit for controlling the transfer stage and the air injection unit to assemble the stud pin inserted from the stud pin insertion unit into the stud hole inside the header. The general operation and configuration of the stud pin insertion device, including the transfer stage, the air injection unit, and the stud pin insertion unit for inserting the stud pin into the header, are obvious to those skilled in the art and are therefore omitted.

[0034] The control unit of the stud pin insertion device can generate the coordinates of the stud hole formed on the tire tread by controlling the work tire using image acquisition means such as a camera and line CAD to scan the tire tread. The control unit controls the x, y, and z transfer stages to transfer the header to the upper part of the stud hole according to the generated stud hole coordinate values, and then lowers the header so that the end of the gripper located at the bottom of the header can be inserted from the entrance of the stud hole to a predetermined depth (S10). Subsequently, the control unit generates air pressure in the pusher located inside the header to lower the pusher, and at the same time, the stud pin located below the pusher can be inserted into the stud hole while the end of the gripper is spread outward (S20). Afterwards, the control unit controls the x, y, and z transfer stages to raise the header, and at the same time, applies vertical force to the stud pin inserted into the stud hole while the end of the gripper is caught on the stud pin's catch tab and in close contact (S30). Finally, the control unit continuously raises the header so that the stud pin inserted into the stud hole receives a vertical force until the end of the gripper is disengaged from the catch of the stud pin, thereby protruding outward to a preset protrusion height relative to the tire tread surface and being assembled into the stud hole (S40).

[0036] The stud pin assembly method of the present invention allows the stud pin to be assembled to a pre-set protrusion height relative to the tire tread surface when the stud pin is assembled into the stud hole by means of a stud pin insertion device. Since this eliminates the need to manually match the height of stud pins having various protrusion heights after assembly, it is possible to improve work efficiency and ensure the production quality of studded tires. Furthermore, the stud pin assembly method allows for the verification of internal defects in the stud hole formed within the tire tread during stud pin assembly. By immediately determining stud pin assembly defects caused by internal defects in the stud hole, the efficiency of tire production quality control can be increased.

[0038] The following describes in detail, through FIGS. 2a to 4, a method for aligning a stud pin inserted into a stud hole to a preset protrusion height and a process for determining internal defects in the stud hole during stud pin assembly by this method.

[0040] FIGS. 2a and 2c are drawings for explaining the header of a stud pin assembly device that automatically inserts a stud pin according to an embodiment of the present invention, and FIG. 3 is a drawing for explaining the gripper of a stud pin assembly device according to an embodiment of the present invention.

[0041] Referring to FIGS. 2a to 3, the header (100) of the stud pin insertion device may include a body (10), a pusher (20) that is located inside the body and descends according to air pressure supplied from an air injection part to insert a stud pin into a stud hole, and a gripper (50) connected to the lower part of the body and receiving a stud pin (200) supplied from a stud pin insertion part (60), and guiding the stud pin to be inserted into the stud hole when the stud pin descends according to the descending of the pusher. One side of the gripper (50) may have a support ring insertion groove (52) formed therein for inserting a support ring (30) to support the gripper so that it is connected to the gripper connection part (11) of the body (10), and on one side of the middle of the gripper, an elastic ring insertion groove (53) may be formed therein for inserting an elastic ring (40) to return the gripper, which is spread outward according to the descending of the stud pin, back to its original state according to the rising of the header. When the gripper (50) is lowered by the header and the end of the gripper is inserted into the stud hole to a predetermined depth, the support ring (50) acts as an axis to guide the end of the gripper outwardly to open the entrance of the stud hole and insert the stud pin into the stud hole. On one side of the lower end (51) of the gripper, a projection (52) that adheres to the catch (221) of the stud pin may be formed to apply force to raise the stud pin vertically when the header rises. The force with which the projection (52) adheres to the catch (221) may be provided by an elastic ring (40) to return the gripper to its original state.

[0042] Meanwhile, the stud pin (200) may include a detachment prevention plate (210) formed at the bottom and inserted into the bottom surface of a '┴'-shaped stud hole to prevent the stud pin from detaching, and a body (220) having a predetermined diameter that is in close contact with the opening of the stud hole at the upper end extending from the detachment prevention plate. The lower part of the body (220) of the stud pin may be formed with a catch (221) having a predetermined inclined surface to apply a predetermined force to cause the stud pin to rise vertically when the header rises by engaging with a projection (52) formed at the bottom of the gripper.

[0044] FIG. 4 is a schematic diagram illustrating stud assembly defects in internal stud holes according to one embodiment of the present invention.

[0045] Referring to FIG. 4(a), a stud pin (200) can be inserted into a stud hole (2) formed in a '┴' shape in the tire tread (1). When the inner surface of the stud hole is normal, as the header rises, the stud pin receives a vertical upward force due to the protrusion at the bottom of the gripper and the catch of the stud pin. When the stud pin can no longer rise due to contact between the anti-detachment plate of the stud pin and the inner upper surface of the stud hole as the header continues to rise, the protrusion slides out of the catch having a predetermined inclined surface, thereby causing the stud pin to rise to a pre-set protrusion height (h) relative to the tire tread surface, so that a stud pin with a uniform protrusion height can be assembled on the tire tread.

[0047] Meanwhile, referring to FIG. 4 (b), if there is a defect in the inner upper surface (2a) of the stud hole, and a force is transmitted to the stud pin (200) that is attached to the gripper as the header rises, the anti-detachment plate of the stud pin is not supported by the defect in the inner upper surface of the stud hole, so it may protrude more than a preset protrusion height from the tire tread surface or protrude at an angle rather than vertically relative to the tire tread surface.

[0048] Defects on the inner upper surface of such stud holes can occur during the creation of the stud holes or when the stud pin anti-dislodgement plate is inserted into the stud hole and impacts the inner upper surface formed at a right angle. Furthermore, if vertical force is not applied to the stud pin when the header rises, considering that the tire is made of rubber with a certain degree of elasticity, a stud pin that is judged to be in a normal state after being partially fitted into the stud hole may become dislodged from the stud hole during driving.

[0050] Therefore, when assembling a stud pin into a stud hole, if a vertical upward force is applied to the stud pin when the header rises after inserting the stud pin, the stud pin is assembled with the anti-detachment plate in contact with the upper inner surface of the stud hole, so the stud pin can be assembled with a uniform height relative to the tire tread, and at the same time, the fastening status of the stud pin due to defects in the inner surface of the stud hole can be immediately determined, thereby increasing the efficiency of quality control for studded tires.

[0052] Although the present invention has been described in detail above through representative embodiments, those skilled in the art will understand that various modifications can be made to the above-described embodiments within the scope of the present invention.

[0053] Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined by the claims set forth below as well as equivalents thereof. Explanation of the symbols

[0055] 1: Tire tread 2: Stud hole 20: Pusher 30: Jijiring 40: Elastic ring 50:Gripper 51: Gripper tip 52:protrusion 100:Header 200:Stud pin 210: Anti-detachment plate 221: Catching

Claims

Claim 1 A method for assembling a stud pin of a stud tire, comprising the steps of: transporting the header of a stud pin insertion device to the upper part of a stud hole and then lowering the header; lowering a pusher to insert a stud pin into the stud hole; and raising the header to apply a vertical force to the stud pin, wherein the step of raising the header to apply a vertical force to the stud pin is characterized by the protrusion formed at the bottom of a gripper and a stopper formed on the stud pin being in close contact by an elastic ring, and wherein the stopper of the stud pin has an inclined surface such that when the stud pin can no longer be raised due to contact between the stud pin's anti-detachment plate and the upper inner surface of the stud hole, the protrusion slides out of the stopper. Claim 2 delete Claim 3 delete

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