JP4487510B2 - Method and apparatus for manufacturing run-flat support - Google Patents

Description

  The present invention relates to a method and an apparatus for manufacturing a run-flat support, and more particularly, a run that can form an annular shell structure without causing wrinkles or breakage even when a metal material having a large breaking stress is used for the blank. The present invention relates to a flat support manufacturing method and apparatus.

  Many run-flat technologies have been proposed that enable emergency traveling of several hundred km even when a pneumatic tire is punctured while the vehicle is traveling. Among these proposals, Patent Document 1 proposes that an annular support 32 is mounted on a rim in a hollow portion of a pneumatic tire 31 assembled to a rim 30 as shown in FIG. The tire 31 punctured by the annular support 32 is supported for run flat running. The run-flat support body 32 includes an annular shell 33 provided with convex portions 33a and 33a projecting outward on the outer periphery, and elastic rings 34 and 34 such as rubber attached to both leg ends of the annular shell 33. Has been. Since the run-flat support body 32 is coaxially mounted on the rim 30 having the existing structure, it can be used as it is without any substantial modification to the existing wheel / rim structure. There is an advantage that you can.

  As described above, since the run-flat support is for supporting a large vehicle weight, the annular shell which is a main component of the support is required to be durable. Therefore, when a metal material having a high breaking stress is generally used. There are many. However, there is a problem that it is very difficult to form the annular shell having the above structure from a blank of a metal material having such a high breaking stress.

  Conventionally, a method disclosed in Patent Document 2 is known as a forming method for processing such an annular shell from a metal blank. In this forming method, forming rollers are arranged on the inner diameter side and the outer diameter side of a cylindrical blank formed by rolling a metal plate into a cylindrical shape, and the peripheral wall of the cylindrical blank is clamped by both the forming rollers. The convex part which continues in the circumferential direction of a cylindrical blank is shape | molded by making it rotate.

However, in this conventional processing method, when both side edges of the cylindrical blank are bent so as to bend from the outside to the inside diameter, a compressive force acts on the peripheral edge to generate wrinkles or breakage. There is a problem that arises. This tendency is more conspicuous especially when the cylindrical blank is made of a metal material having a large breaking stress, so that there has been a problem that the run-flat durability cannot be dramatically improved.
JP-A-10-297226 German patent specification DE10149086C1

  An object of the present invention is to provide a method and apparatus for manufacturing a run-flat support body that can form an annular shell structure without causing wrinkles or breakage even when a metal material having a large breaking stress is used for the blank. It is in.

The method for manufacturing a run-flat support body of the present invention includes a rotating frame composed of a cylindrical holding frame and a disk-like support body fixed to the back surface of the holding frame , and the axial direction and diameter of the rotating frame. Using a molding device having a single disk-shaped molding blade that is movable in the direction, and fixing a cylindrical blank inside the holding frame at one side edge in a fixed position, and the other side edge The inner peripheral surface of the cylindrical blank peripheral wall while rotating the rotary frame with a gap between the inner peripheral surface of the holding frame and the outer peripheral surface of the cylindrical blank. The outer peripheral surface of the molding blade is contacted to the side, reciprocated radially outward from one side edge fixed to the fixed position and moved toward the other side edge set movably, with circumferentially continuous peripheral wall, the initial tubular blank It is characterized in that for molding the annular shell having at least one protrusion protruding on the outer circumferential side from the wall.

In addition, the run-flat support manufacturing apparatus of the present invention includes a rotating frame coupled to a rotating shaft, and a forming blade formed in a single disk shape movable in the axial direction and the radial direction of the rotating frame. The rotating frame is composed of a cylindrical holding frame and a disk-like support body that is fixed to the rear surface of the holding frame and to which the rotating shaft is connected, and a cylindrical blank is placed inside the holding frame. The other side edge is fixed to a fixed position, and the other side edge is set to be movable so that a gap is formed between the inner peripheral surface of the holding frame and the outer peripheral surface of the cylindrical blank. configured to, contact pressure to the outer peripheral surface of the forming blade to the inner diameter side of the tubular blank wall, and the set to be the move with reciprocating from one side edge of which is fixed in position radially outward and a control unit that moves toward the other side edge And it is characterized in and.

  As described above, with one side edge of the cylindrical blank fixed to a fixed position on the rotating frame and the other side edge set to be movable, a molding blade is placed on the inner diameter side of the peripheral wall of the cylindrical blank. Pushing and reciprocating in the outer diameter direction from the side edge on the fixed side, and moving toward the side edge on the movable side, so that the fixed part on the side edge of the cylindrical blank is not deformed In addition, it is possible to mold so as to expand only the intermediate region. Therefore, since the molding is performed without concentrating strain such as compressive stress on the fixing portion of the side edge portion, even the cylindrical blank made of a metal material having a large breaking stress is wrinkled or broken at the side edge portion. An annular shell having a convex portion on the peripheral wall can be formed without any problem. In addition, since the actual state of molding is bending, the cylindrical blank can be molded to have a uniform thickness with almost no change, and an annular shell having excellent durability can be obtained.

  In the present invention, the cylindrical blank refers to an intermediate blank made of a metal material before being formed into an annular shell. The method for producing the cylindrical blank is not particularly limited, but preferably, a planar metal plate cut into a rectangle is bent into a roll shape, its both end portions are welded to each other, and the welded portion is polished smoothly. What you did is good. Alternatively, a tubular body may be obtained by cutting a steel pipe having a predetermined inner diameter into a predetermined width.

  The metal material constituting the cylindrical blank is not particularly limited as long as it has the durability required for run-flat travel, but in order to ensure further excellent durability, preferably the breaking stress is 600 MPa or more, more preferably, It is preferable to use a metal material of 800 to 1200 MPa, particularly steel. In the case of a metal material having a high breaking stress of 600 MPa or more, when the conventional forming method described above is used to bend the side edge portion inward in the radial direction, the side edge portion is wrinkled or broken. However, the processing method of the present invention can be molded without causing wrinkles or breakage. Therefore, it is possible to obtain a run-flat support body having further excellent durability.

  In the present invention, the shape of the peripheral wall of the cylindrical blank is not particularly limited, but preferably a planar shape in a cross section including the axis. That is, it is a right cylindrical shape, and it is preferable that the inner diameter is substantially the same as the minimum inner diameter of the annular shell after molding. In this way, by making the inner diameter of the cylindrical blank substantially the same as the minimum inner diameter of the annular shell after molding, it is only necessary to expand the intermediate region without deforming the side edge of the peripheral wall. As in the processing method, a compressive force or the like is not applied to the side edge portion. Therefore, even if it is a metal material with a big breaking stress, an annular shell can be shape | molded without producing a wrinkle and a fracture | rupture in a side edge part.

  In the present invention, the thickness of the peripheral wall of the cylindrical blank is not particularly limited, but is preferably 1.0 to 2.0 mm. If the thickness is thinner than 1.0 mm, the workability is improved, but the durability is lowered. On the other hand, if the thickness is greater than 2.0 mm, the weight of the tire / wheel assembly increases and the fuel consumption of the automobile deteriorates.

  The molding apparatus used in the manufacturing method of the present invention uses an apparatus that includes a rotary frame that is rotationally driven and a molding blade that is movable in the axial and radial directions of the rotary frame. The forming blade is moved on the inner side (inner diameter side) of the rotary frame, and the radial and axial movements relative to the rotary frame are controlled by numerical control (NC control) or the like.

  In order to form an annular shell having at least one convex portion on the peripheral wall of the cylindrical blank using the above molding device, first, the cylindrical blank is rotated coaxially with the rotary frame of the molding device and integrally with the rotary frame. Set to do. Moreover, when a cylindrical blank is set to a rotation frame, one side edge part is fixed to a fixed position, and it is made not to move relatively to both a radial direction and an axial direction with respect to a rotation frame. The other side edge is supported so as to be movable at least in the axial direction.

  The side edge on the movable side is preferably allowed to move only in the axial direction and is restricted so as not to move in the radial direction. More preferably, it is desirable to restrict to the same radial position as the side edge portion on the fixed position fixing side. As a means for regulating the movable side edge portion in this way, for example, a ring is provided inside the rotary frame so as to be slidable in the axial direction, and the movable side edge portion is connected to this ring, May be biased toward the side edge on the fixed position fixing side by an actuator such as a spring or a hydraulic cylinder. Alternatively, the movement of the side edge on the moving side can be restricted by arranging an uneven mold having a shape corresponding to the outer peripheral shape of the annular shell after molding on the radially outer side of the cylindrical blank.

  When the cylindrical blank is set on the rotating frame as described above, the cylindrical blank is formed by being movable in the axial direction and the radial direction by a forming blade while rotating the rotating frame. In this moving operation, the molding blade is pressed against the inner diameter side of the peripheral wall of the cylindrical blank, and is reciprocated in the radial direction from the side edge portion on the fixed position fixed side, and is moved toward the side edge portion on the movable side. To do. By the operation of moving the forming blade, the intermediate area of the peripheral wall of the cylindrical blank is expanded outwardly in a convex shape, and the side edge on the movable side is directed toward the side edge on the fixed position fixed side due to the diameter expansion. Move little by little.

  In this way, by moving the forming blade from the side edge on the fixed position fixed side to the side edge on the movable side, a convex portion whose diameter is increased outward is formed on the peripheral wall of the cylindrical blank. In this case, after finishing the forward path, the forming blade is moved from the movable side edge to the fixed position side edge in the direction opposite to the forward path, and the convex portion processed in the forward path May be reshaped. Moreover, you may make it repeat the said reciprocating shaping | molding 2 times or more as needed. Such reciprocating molding is effective, for example, when the material of the cylindrical blank is made of a metal material having a large breaking stress, and enables molding with higher dimensional accuracy.

  Moreover, since the side edge part of a cylindrical blank is bend | folded radially outside by using the corner | angular part (corner part) of a fixed holding part as a fulcrum, it is preferable to chamfer the corner | angular part circularly. This chamfering prevents the bent portion of the side edge from being bent with an excessively small radius of curvature, thereby avoiding the occurrence of wrinkles and breakage due to stress concentration. The curvature radius of the chamfered portion is preferably about 2 to 10 mm.

  In the present invention, there may be at least one convex portion of the annular shell to be molded into the cylindrical blank, but preferably it is two. Since the convex portion of the annular shell serves to support the inner peripheral surface of the pneumatic tire during run-flat running, if there is only one convex portion, the load will concentrate on one place and damage to the tire will be accelerated. . Further, when there are three or more convex portions, the contact area per convex portion is minimized, so that damage to the tire is also accelerated.

  Hereinafter, the present invention will be specifically described based on embodiments shown in the drawings.

  FIG. 1 illustrates a molding apparatus used in the present invention.

In the figure, 1 is a rotating frame and 2 is a forming blade. The rotating frame 1 has a cylindrical holding frame 1a, a disk-like support plate 1b is fixed to the back surface thereof, and is rotated by a rotating shaft 3 connected to the axis of the support plate 1b. . On the other hand, the forming blade 2 is formed in a disc shape, and the outer peripheral contact portion is formed in an arc-shaped cross section. The forming blade 2 is rotationally driven by a drive shaft 4 and is moved by a drive unit 5 in the radial direction (X direction) and the axial direction (Y direction) of the rotary frame 1. The moving operation is numerically controlled (NC control) by a program set in advance in a control unit (not shown).

  A cylindrical blank B that is a workpiece is set in the holding frame 1 a of the rotating frame 1. In the rotating frame 1 (holding frame 1a), the cylindrical blank B has one side edge fixed to a flange 1f at a fixed position by a grip ring 6a and a bolt 6b, and is restricted from moving in the radial direction and the axial direction. . The other side edge portion is fixed to the ring 8 slidably inserted in the rotation frame 1 (holding frame 1a) in the axial direction by the grip ring 7a and the bolt 7b. It can be moved. As for the gripping surfaces on the inner peripheral side of the gripping rings 6a and 7a, corners (corner portions) serving as fulcrums when the side edges of the cylindrical blank B are bent are chamfered by an arc having a curvature radius of about 2 to 10 mm. Yes. Further, the ring 8 is urged by a spring 9 that is uniformly arranged in the circumferential direction of the support plate 1b, and the movable side edge of the cylindrical blank B is directed toward the fixed side edge (flange 1f). To be energized.

  2 (A) to 2 (C) show that the cylindrical blank B set on the rotating frame 1 (holding frame 1a) as described above is turned into an outer peripheral annular shell S indicated by a chain line by a moving operation of the forming blade 2. FIG. The case where it is molded is shown.

  First, as shown in FIG. 2A, the molding blade 2 is inserted into the inner diameter side of the peripheral wall of the cylindrical blank B supported by the rotating frame 1 (holding frame 1a), and the fixed position of the cylindrical blank B is fixed. Press against the inner surface of the side edge of the side (the side fixed to the bolt 6b).

  Next, as shown in FIGS. 2 (B) and 2 (C), the abutting portion of the forming blade 2 is aligned with the outer peripheral surface shape (convex portion) of the annular shell S indicated by a chain line, and the side edge portion on the fixed position fixing side. And is reciprocated so as to increase the diameter outward in the radial direction and in the axial direction, and the convex portion is formed on the peripheral wall of the cylindrical blank B so as to be continuous in the circumferential direction. Thus, in the process in which the convex portion is formed on the peripheral wall of the cylindrical blank B, the side edge portion on the moving side connected to the ring 8 is urged by the spring 9 and gradually moves to the fixed position fixing side. The movement changes according to the length of the movement locus along which the forming blade 2 forms the peripheral wall. In this way, as shown by a chain line in the figure, the annular shell S having an outer peripheral surface in which two convex portions are arranged radially outward is formed.

  The operation of forming the cylindrical blank B according to the present invention into the annular shell S may be completed only in the forward process of FIGS. 2A to 2C described above. May be moved from the side edge portion on the movable side to the side edge portion on the fixed position fixed side in the reverse direction, and an operation of re-forming the convex portion that has been processed in the forward path step may be performed. Further, this reciprocating molding process may be repeated at least twice.

  The annular shell S molded in accordance with the present invention supports the side edge of the cylindrical blank B in a fixed state in a fixed position and expands only the intermediate area of the peripheral wall, so that the side edge is substantially deformed. Will not be added. Therefore, the annular shell can be formed without causing wrinkles or breakage of the side edge portion that has occurred in the conventional method.

  In the present invention, this effect does not change even when a cylindrical blank made of a metal material having a breaking stress of 600 MPa or more is formed. However, when molding a cylindrical blank of such a high breaking stress metal material, 75 to 85% of the final shape is molded by the above-described molding method, and then the inner and outer sides of the intermediate molded annular shell are formed. If a molding roller is pressed against each other to finish the final shape, high-precision molding can be achieved without further wrinkling or breaking.

  In addition, the operation of moving the forming blade in the illustrated example is performed by previously storing the outer peripheral shape of the annular shell S indicated by the chain line after forming in the control unit and performing numerical control based on the stored data. This movement is made to follow by the bias of the spring. However, for the movement operation of the side edge on the moving side, instead of the biasing force of the spring, an actuator such as a hydraulic cylinder may be connected and moved by this actuator. Further, the movement operation of the actuator may be based on the data related to the outer peripheral shape of the annular shell previously stored in the control unit as described above, or a sensor that detects the movement trajectory of the forming blade in the radial direction and the axial direction. And may be controlled based on data of the movement trajectory detected by the sensor over time.

It is the schematic which illustrated embodiment of the shaping | molding apparatus used for this invention. (A)-(C) are explanatory drawings which show the process of shape | molding a cylindrical blank using the shaping | molding apparatus of FIG. It is sectional drawing of the tire / rim structure for run flats which incorporated the cyclic | annular shell which is a manufacturing object of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rotating frame 1a Holding frame 1b Support plate 1f Flange 2 Molding blade 3 Rotating shaft 5 Drive part 6,7 Bolt 8 Ring 9 Spring B Cylindrical blank S Annular shell

Claims (18)

A rotating frame composed of a cylindrical holding frame and a disc-like support fixed to the back of the holding frame , and a single disc shape movable in the axial direction and the radial direction of the rotating frame . Using a molding device having a molding blade, a cylindrical blank is fixed inside the holding frame at one side edge portion in a fixed position, and the other side edge portion is set to be movable. With the gap between the inner peripheral surface and the outer peripheral surface of the cylindrical blank, the outer peripheral surface of the molding blade is brought into pressure contact with the inner diameter side of the cylindrical blank peripheral wall while rotating the rotating frame, While reciprocating radially outward from one side edge fixed at a fixed position and moving toward the other side edge set so as to be movable, the peripheral wall is continuous in the circumferential direction, and the cylindrical blank at least one protruding on the outer circumferential side than the initial wall Method of manufacturing a run-flat support body for forming an annular shell having a part. The method for manufacturing a run-flat support body according to claim 1, wherein one side edge portion fixed at the fixed position is set to a minimum inner diameter of the annular shell. The other side edge portion set so as to be movable is constrained to the same radial position as that of the one side edge portion fixed at the fixed position so as to be movable in the axial direction. A method for producing a run-flat support.   The manufacturing method of the run-flat support body in any one of Claims 1-3 which has arrange | positioned the uneven | corrugated type | mold corresponding to the outer peripheral shape of the said annular shell on the outer side of the radial direction of the said cylindrical blank. The run-flat support body according to any one of claims 1 to 4, wherein an urging force is applied toward the one side edge portion fixed to the fixed position on the other side edge portion set so as to be movable. Production method. The run flat according to any one of claims 1 to 4, wherein an actuator is provided on the other side edge portion set so as to be movable, and the actuator is operated in accordance with a movement trajectory in a radial direction and an axial direction of the forming blade. For producing a support for an automobile. The sensor which detects the movement locus | trajectory of the radial direction of the said shaping | molding blade and an axial direction is provided, Based on the detection data of this movement locus | trajectory, the movement of the other side edge part set to the said movement by the said actuator is controlled. 5. A method for producing a run-flat support according to any one of 4 above.   The manufacturing method of the support body for run flats in any one of Claims 1-7 which shape | molds the cyclic | annular shell in which the said convex part was arranged in the surrounding wall of the said cylindrical blank.   The method for manufacturing a run-flat support body according to any one of claims 1 to 8, wherein a shape of a lateral surface of the pressure contact end of the forming blade is an arc. The molding blade is moved from one side edge fixed to the fixed position to the other side edge set so as to be movable to form a convex part, and then from the other side edge set so as to be movable. The run-flat support body according to any one of claims 1 to 9, wherein the convex portion is reshaped by moving backward to one side edge portion fixed at the fixed position , and the reciprocating molding is repeated at least once. Manufacturing method.   The method for producing a run-flat support body according to any one of claims 1 to 10, wherein after forming the annular shell, a forming roller is further pressed to the inside and outside of the annular shell to finish the final shape. .   The method for manufacturing a run-flat support according to any one of claims 1 to 11, wherein the cylindrical blank is made of a metal material having a breaking stress of 600 MPa or more. A rotating frame coupled to the rotating shaft; and a molding blade formed in a disk shape movable in the axial direction and the radial direction of the rotating frame, the rotating frame including a cylindrical holding frame and the holding frame And a disk-shaped support body to which the rotating shaft is coupled, and a cylindrical blank is fixed inside the holding frame at one side edge portion in a fixed position, and the other side edge part set movably, is configured to a state in which a gap between the inner peripheral surface of the holding frame and the outer peripheral surface of the tubular blank, the tubular outer peripheral surface of the forming blade Provided with a control unit that is in contact with the inner diameter side of the blank peripheral wall, reciprocates radially outward from one side edge fixed at the fixed position, and moves toward the other side edge set to be movable. Run flat support manufacturing equipment. The run flat support manufacturing apparatus according to claim 13, wherein the other side edge portion set to be movable is constrained to the same radial position as the one side edge portion fixed to the fixed position .   The run-flat support manufacturing apparatus according to claim 13 or 14, wherein a concavo-convex shape corresponding to an outer peripheral shape of the annular shell is arranged outside in a radial direction of the cylindrical blank. Wherein the side edges of the movable set the other hand, support for run-flat according to any one of claims 13 to 15 in which a spring for biasing said one side edge portion of which is fixed in position Body manufacturing equipment. The manufacturing apparatus of the support body for run flats in any one of Claims 13-15 which provided the actuator in the other side edge part set to the said movement . 18. The sensor according to claim 17, wherein a sensor that detects a movement trajectory in the radial direction and the axial direction of the forming blade is provided, and movement control of the other side edge portion that is set to be movable by the actuator is performed based on detection data of the movement trajectory. Equipment for a run-flat support.

Images