JP5261135B2 - Dimple forming burnishing tool and dimple forming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a burnishing tool for forming dimples capable of forming dimples on an outer peripheral surface of a workpiece without using an exclusive mechanical equipment. <P>SOLUTION: The dimple-forming burnishing tool 1 comprises: a head body 30; a support roller 40 rotatably and externally fitted to a roller shaft part 32 formed at the head body 30; a retainer 50 arranged on an outer periphery of the support roller 40; and a roller 60 and a ball 70 rotatably retained by the retainer 50. A protrusion 44a which contacts the ball 70 is formed on an outer peripheral surface of the support roller 40. Rotation of the support roller 40 and contact of the ptotrusion 44a to the ball 70 press the ball 70 to the surface of the workpiece. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a burnishing tool and a dimple forming method for forming dimples on the surface of a workpiece.

  In sliding parts such as engines, by forming fine grooves and dimples on the sliding surface and improving the lubricating performance of the sliding surface, it is possible to improve seizure resistance and reduce frictional resistance. . As a method of forming dimples on the outer peripheral surface of the sliding component, there are methods using WPC processing (fine particle shot peening) and laser processing (for example, see Patent Document 1).

Japanese Patent Laying-Open No. 2004-345022 (paragraph 0016, FIG. 5)

  However, in order to perform WPC processing and laser processing, it is necessary to use a dedicated machine facility, which causes a problem that processing costs increase.

  Therefore, in the present invention, the dimple formation burnishing tool and the dimple formation that can solve the above-described problems, can form dimples on the outer peripheral surface of the workpiece without using dedicated mechanical equipment, and can reduce processing costs. It is an object to provide a method.

In order to solve the above-mentioned problems, a dimple formation burnishing tool according to the present invention includes a head body, a support roller that is rotatably fitted to a roller shaft portion provided upright on a mounting surface of the head body , and the head. A retainer having a mounting portion that is mounted on the mounting surface of the body , and a plate-shaped holding portion that is disposed on the outer periphery of the support roller is raised from an edge of the mounting portion in the axial direction of the roller shaft portion When, and a roller and a ball held in a rotatable state by the holding portion, the outer peripheral surface of the roller is configured to protrude on the outer surface of the holding portion, the support roller at the inner surface side of the holding portion contact with the outer peripheral surface of the outer surface of the ball, with a retractable to the outer surface side of the holding portion protrudes on the inner surface side of the holding portion, on the outer circumferential surface of the support roller, A convex portion that contacts the ball is formed, and when the roller rolls on the surface of the workpiece, the support roller rotates in conjunction with the rotation of the roller, and the convex portion of the support roller contacts the ball Thus, the ball is pressed against the surface of the workpiece.

  In order to solve the above-mentioned problem, the dimple formation method of the present invention is a dimple formation method using the dimple formation burnishing tool, wherein the roller and the ball are brought into contact with the surface of the work, and the work is rotated. Accordingly, when the roller rolls on the surface of the workpiece, the support roller rotates in conjunction with the rotation of the roller, and the convex portion of the support roller contacts the ball, so that the ball is A dimple is formed on the surface of the workpiece by being pressed against the surface of the workpiece.

In these configurations, when the ball is pressed against the surface of the workpiece, dimples can be formed on the surface of the workpiece due to the peening effect of the ball on the surface of the workpiece. Specifically, the ball can be pressed against the surface of the workpiece by rotating the workpiece assembled on a lathe or machining center and rolling the roller on the surface of the workpiece. In other words, the dimples can be formed on the work by position control by the drive part of the machine equipment for cutting such as a lathe or machining center without using dedicated mechanical equipment to form the dimple on the work. Cost can be reduced.
Further, by pressing a ball or a roller against the surface of the workpiece, the surface hardness of the workpiece can be increased and compressive residual stress can be applied to the workpiece.
In addition, when the roller is arranged on the rear side in the tool feeding direction, the bulge generated around the dimple when the dimple is formed by the ball can be processed smoothly by the roller.

  In the dimple formation burnishing tool described above, it is desirable that the rotation axis of the roller and the rotation axis of the support roller are arranged in parallel.

  In this configuration, since the outer peripheral surface of the roller and the outer peripheral surface of the support roller can be brought into contact with each other in parallel, the transmission efficiency of the rotational force can be increased between the roller and the support roller.

  In the dimple forming burnishing tool described above, a contact region having a polygonal outer peripheral shape is provided on the outer peripheral surface of the support roller, and the convex portion is formed by a corner portion formed in the contact region. can do.

  In this configuration, the convex portion can be easily formed by processing the outer peripheral shape of the support roller into a polygon.

  In the dimple formation burnishing tool described above, the retainer can be configured to hold the integrated ball and the two rollers disposed on both sides of the ball.

  In this configuration, the roller on the front side in the feed direction of the tool can process unevenness due to cutting of the workpiece surface smoothly, and dimples can be formed by the balls at the smooth finished portion. Further, with the roller on the rear side in the tool feeding direction, when the dimple is formed on the surface of the workpiece by the ball, the swelling generated around the dimple can be processed smoothly.

  According to the dimple formation burnishing tool and the dimple formation method of the present invention, by using position control by a drive unit of a cutting machine such as a lathe or a machining center without using a dedicated machine for forming a dimple on a workpiece. Since the dimples can be formed on the workpiece, the processing cost can be reduced. In addition, the surface hardness of the workpiece can be increased and compressive residual stress can be applied to the workpiece. Further, when the dimple is formed, the bulge generated around the dimple can be processed smoothly by the roller.

Next, embodiments of the present invention will be described in detail with reference to the drawings as appropriate.
In this embodiment, a case where a work assembled on a lathe or a machining center is rotated and dimples are formed on the outer peripheral surface of the work will be described as an example.

  As shown in FIG. 1A, the dimple formation burnishing tool 1 includes a body 10, a drive shaft 20 that is inserted into the body 10, and has a tip portion protruding from the tip surface of the body 10, and the drive shaft 20. A head body 30 attached to the front end surface of the head, a support roller 40 fitted on a roller shaft portion 32 formed on the head body 30, a retainer 50 disposed on the outer periphery of the support roller 40, and the retainer 50, and a roller 60 and a ball 70 held in a rotatable state.

  The body 10 is a rectangular parallelepiped member, and a plate-like shank 11 held by a lathe or a machining center is attached to a side surface. Further, a preload adjustment knob 12 having a distal end portion inserted into the body 10 projects from the base end surface of the body 10.

The drive shaft 20 is a shaft member having a circular cross section inserted into the body 10, and a distal end portion projects from the distal end surface of the body 10. An enlarged flange portion 21 is formed at the distal end portion of the drive shaft 20.
Further, the base end portion of the drive shaft 20 is connected to the distal end portion of the preload adjustment knob 12 via a spring (not shown) in the body 10, and the drive shaft 20 is operated by operating the preload adjustment knob 12. The amount of protrusion can be changed.

  As shown in FIG. 2, the head body 30 is formed on a plate-like support portion 31 having an attachment surface 31 a formed thereon, a roller shaft portion 32 erected on the attachment surface 31 a, and a base end portion of the support portion 31. And a disc-shaped flange portion 33. The head body 30 is supported by the drive shaft 20 by attaching the proximal end surface of the flange portion 33 to the distal end surface of the flange portion 21 of the drive shaft 20 (see FIG. 1).

The roller shaft portion 32 is a shaft member having a circular cross section formed in an axial direction orthogonal to the axial direction of the drive shaft 20 (see FIG. 1).
On the outer peripheral surface of the roller shaft portion 32, a lubricating groove 32a is formed over the entire circumference in the intermediate portion in the axial direction. One end of an oil supply path (not shown) formed in the support portion 31 and the roller shaft portion 32 is opened in the lubrication groove 32a, and from the grease nipple N provided in the support portion 31 through the oil supply route. Lubricating oil can be supplied.

  The retainer 50 is formed with a disc-like attachment portion 51 attached to the attachment surface 31a of the head body 30 and a plate-like holding portion 52 raised from the edge of the attachment portion 51 on the front end side. Yes.

  A through hole 51a is formed at the center of the attachment portion 51. When the attachment portion 51 is attached to the attachment surface 31a, the roller shaft portion 32 of the support portion 31 is inserted into the through hole 51a.

The holding portion 52 is raised to a part of the edge portion on the tip side of the attachment portion 51 (about ¼ of the entire circumference in the present embodiment), and is curved along the edge portion of the attachment portion 51. .
As shown in FIG. 1B, a holding groove 53 that is vertically long in the height direction passes through an intermediate portion in the width direction of the holding portion 52. The holding groove 53 is a portion where a roller 60 and a ball 70 described later are held.

  As shown in FIG. 2, the support roller 40 is a cylindrical member, and a bearing 41 is internally provided on the inner peripheral portion thereof. The support roller 40 is externally fitted to the roller shaft portion 32 on the outer side (upper side in FIG. 2) than the mounting portion 51 of the retainer 50 and is rotatable about the axis of the roller shaft portion 32.

  An annular spacer 42 is interposed between the bearing 41 and the mounting portion 51. A disk-shaped cover 43 is attached to the upper surface of the bearing 41. The support bolt 40 is screwed into the screw hole 32b formed in the upper surface of the roller shaft portion 32 by screwing the fixing bolt 43b inserted through the through hole 43a formed in the center portion of the cover 43, so that the support roller 40 has the roller shaft portion 32. Is attached.

  On the upper part of the outer peripheral surface of the support roller 40, a contact region 44 is formed in which a plurality of convex portions 44a are formed at equal intervals in the circumferential direction. In the present embodiment, as shown in FIG. 3, the outer peripheral shape of the contact region 44 is formed in a polygon (decagonal in the present embodiment), and ten convex portions are formed by the corners formed on the outer peripheral surface. 44a ... are formed.

  As shown in FIG. 2, the roller 60 is a rotating body having a circular cross section that extends in an axial direction parallel to the axial direction of the roller shaft portion 32. The roller 60 is held at a lower portion in the holding groove 53 of the retainer 50 (see FIG. 1), and is rotatable about an axis in the holding groove 53. Since the axial direction of the roller 60 and the axial direction of the roller shaft portion 32 are parallel, the rotational axis of the roller 60 and the rotational axis of the support roller 40 are arranged in parallel.

  Further, as shown in FIG. 1, the outer peripheral surface of the roller 60 held in the holding groove 53 protrudes to the outer surface side of the retainer 50 and also protrudes to the inner surface side of the retainer 50, so that the outer peripheral surface of the support roller 40 It touches the bottom.

As shown in FIG. 2, the ball 70 is a sphere that is held in the upper part of the holding groove 53 of the retainer 50 (see FIG. 1), and is freely rotatable in the holding groove 53.
The outer surface of the ball 70 protrudes to the outer surface side of the retainer 50, and the ball 70 is movable in the retaining groove 53 in the thickness direction of the retainer 50. That is, the outer surface of the ball 70 can freely appear and disappear on the outer surface side of the retainer 50. Further, the outer surface of the ball 70 also protrudes to the inner surface side of the retainer 50.

Next, a dimple formation method using the dimple formation burnishing tool 1 of the present embodiment will be described.
When forming dimples on the outer peripheral surface (surface) of a workpiece using the dimple formation burnishing tool 1, first, the workpiece is assembled to a lathe or a chuck of a machining center, and the dimple formation burnishing tool 1 shown in FIG. 1 is assembled to a bed. . At this time, the head body 30 side is arranged facing the work side (front end side).
Then, with the workpiece rotated, the dimple formation burnishing tool 1 is moved to the workpiece side using a lathe or a driving unit of a machining center, and the outer circumferential surface of the roller 60 protruding from the retainer 50 is brought into contact with the outer circumferential surface of the workpiece. .

  When the roller 60 comes into contact with the rotated workpiece, the roller 60 rotates about the axis in conjunction with the rotation of the workpiece due to frictional resistance between the outer circumferential surface of the workpiece and the outer circumferential surface of the roller 60. Further, the support roller 40 rotates about the axis in conjunction with the rotation of the roller 60 due to the frictional resistance between the outer peripheral surface of the roller 60 and the outer peripheral surface of the support roller 40.

As shown in FIG. 4, when the support roller 40 rotates and the convex portion 44 a formed in the contact region 44 of the support roller 40 contacts the ball 70, the ball 70 is pushed out of the retainer 50, and the surface of the workpiece is Due to the strong pressing, dimples D are formed on the surface of the workpiece due to the peening effect of the balls 70 on the surface of the workpiece.
The plurality of convex portions 44a... Formed in the contact region 44 of the support roller 40 intermittently contact the ball 70 so that the ball 70 rolls while vibrating with respect to the surface of the workpiece. Thus, a plurality of dimples D ... are formed on the surface of the workpiece.
Further, the dimple formation burnishing tool 1 shown in FIG. 1 is moved in the axial direction of the workpiece to form dimples on the entire surface of the workpiece.

In the dimple formation burnishing tool 1 and the dimple formation method as described above, position control is performed by a driving unit of a cutting machine such as a lathe or a machining center without using a dedicated machine for forming a dimple on a workpiece. Since the dimples can be formed on the workpiece, the processing cost can be reduced.
Further, as shown in FIG. 4, by pressing a ball 70 or a roller 60 against the surface of the workpiece, the surface hardness of the workpiece can be increased and compressive residual stress can be applied to the workpiece.
Further, by disposing the roller 60 on the rear side in the tool feeding direction with respect to the ball 70, when the dimple is formed by the ball 70, the bulge generated around the dimple can be processed smoothly by the roller 60. .

  Further, as shown in FIG. 1, since the rotation axis of the roller 60 and the rotation axis of the support roller 40 are arranged in parallel, the outer peripheral surface of the roller 60 and the outer peripheral surface of the support roller 40 are in a parallel state. Since the contact can be made, the transmission efficiency of the rotational force can be increased between the roller 60 and the support roller 40.

  Further, as shown in FIG. 3, on the outer peripheral surface of the support roller 40, the outer peripheral shape of the contact region 44 that contacts the ball 70 is formed in a polygonal shape, and the convex portion 44 a is Since it forms, the some convex part 44a ... can be easily formed in the outer peripheral surface of the support roller 40. FIG.

The embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the spirit of the present invention.
In the present embodiment, as shown in FIG. 3, the outer peripheral shape of the contact region 44 of the support roller 40 is formed in a decagon and ten convex portions 44 a... Are formed in the contact region 44. The number of convex portions 44a formed in the region 44 is not limited. For example, when a support roller having a hexagonal outer peripheral shape in the contact area is used, dimples are formed on the surface of the work as shown in FIG. When the support roller formed in a square shape is used, dimples are formed on the surface of the workpiece as shown in FIG.

  In addition, as shown in FIG. 6, two rollers 60, 60 may be arranged above and below the ball 70. In this configuration, the roller 60 on the front side in the feed direction of the tool can be used to smoothly process the unevenness due to the cutting of the workpiece surface, and the dimples can be formed by the balls 70 in the smooth finished portion. Further, in the roller 60 on the rear side in the tool feeding direction, when the dimples are formed on the surface of the workpiece by the balls 70, the swelling generated around the dimples can be processed smoothly.

  Further, in this embodiment, as shown in FIG. 4, the dimples are formed on the outer peripheral surface of the workpiece, but the head body 30 of the dimple forming burnishing tool 1 shown in FIG. 1 is inserted into the inner peripheral portion of the workpiece, By bringing the roller 60 and the ball 70 into contact with the inner peripheral surface of the work, dimples can be formed on the inner peripheral surface of the work.

It is the figure which showed the dimple formation burnishing tool of this embodiment, (a) is a side view, (b) is the figure seen from the front end side. It is the disassembled perspective view which showed the front-end | tip part of the dimple formation burnishing tool of this embodiment. It is the figure which showed the front-end | tip part of the dimple formation burnishing tool of this embodiment, and is AA sectional drawing of FIG. It is the enlarged view which showed the aspect when forming a dimple on the surface of a workpiece | work with the dimple formation burnishing tool of this embodiment. FIG. 5 is a diagram showing dimples formed on the surface of a workpiece by the dimple forming burnishing tool of the present embodiment, and (a) is a development view when using a support roller in which the outer peripheral shape of the contact region is formed in a hexagon, (B) is a development view in the case of using a support roller in which the outer peripheral shape of the contact area is formed in a dodecagon. It is the figure which showed the dimple formation burnishing tool of other embodiment, and is a side view of the structure which has arrange | positioned two rollers on the both sides of a ball | bowl.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Dimple formation burnishing tool 10 Body 11 Shank 20 Drive shaft 21 Flange part 30 Head body 31 Support part 31a Mounting surface 32 Roller shaft part 33 Flange part 40 Support roller 41 Bearing 44 Contact area 44a Convex part 50 Retainer 51 Mounting part 52 Holding part 53 Holding groove 60 Roller 70 Ball D Dimple

Claims (5)

Head body,
A support roller externally fitted in a freely rotatable state to a roller shaft portion erected on the mounting surface of the head body;
A plate-like holding portion that has an attachment portion that is attached to the attachment surface of the head body and is arranged on the outer periphery of the support roller is raised from an edge of the attachment portion in the axial direction of the roller shaft portion. A retainer,
A roller and a ball held in a rotatable state on the holding unit , and
The outer peripheral surface of the roller is configured to protrude on the outer surface of the holding portion, in contact with the outer peripheral surface of the support roller at the inner surface side of the holding portion,
The outer surface of the ball, with a retractable to the outer surface side of the holding portion protrudes on the inner surface side of the holding portion,
On the outer peripheral surface of the support roller, a convex portion that contacts the ball is formed,
When the roller rolls on the surface of the workpiece, the support roller rotates in conjunction with the rotation of the roller, and the convex portion of the support roller contacts the ball, so that the ball contacts the surface of the workpiece. A dimple-forming burnishing tool characterized by being pressed.   The dimple-forming burnishing tool according to claim 1, wherein the rotation axis of the roller and the rotation axis of the support roller are arranged in parallel.   A contact region having a polygonal outer peripheral shape is provided on the outer peripheral surface of the support roller, and the convex portion is formed by a corner portion formed in the contact region. The dimple formation burnishing tool according to claim 1 or 2.   The retainer holds the integrated ball and the two rollers disposed on both sides of the ball. 4. Dimple forming burnishing tool. A dimple formation method using the dimple formation burnishing tool according to any one of claims 1 to 4,
When the roller and the ball are brought into contact with the surface of the workpiece and the roller rolls on the surface of the workpiece as the workpiece rotates, the support roller rotates in conjunction with the rotation of the roller, and the support A dimple formation method, wherein a dimple is formed on a surface of the workpiece by pressing the convex portion of a roller against the ball and pressing the ball against the surface of the workpiece.

Images