JP2017077601A - Burnishing method, and roller and roller burnishing tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a burnishing method capable of suppressing formation of an unworked portion and a worked mark even in a workpiece having an abutting portion (step portion).SOLUTION: A roller 6 has a tip worked portion 6a formed into an arc shape having a radius of curvature of 0.1 mm or more and 0.7 mm or less by working a worked surface Wa, and a slid portion 6c which is connected to the tip worked portion 6a and is slid by the worked surface Wa. A burnishing method for working the worked surface Wa by pressing a roller 6 against the worked surface includes arranging and working the roller 6 so that a back taper angle formed by the slid portion 6c with respect to the worked surface Wa is 0.5° or more and 3° or less.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a burnishing method, a roller (also referred to as “roll”), and a roller burnishing tool.

  Currently, the minimum value of the radius of curvature of the tip of a cutting tip used for cutting is generally 0.2 mm. Therefore, when a workpiece having an abutting portion (step portion) is manufactured by cutting using this cutting tip, a corner portion having a radius of 0.2 mm is formed in the abutting portion.

  FIG. 10 is an enlarged longitudinal sectional view showing a conventional roller burnishing tool. FIG. 11 is an explanatory view showing a state when the abutting portion of the workpiece is machined with a conventional roller burnishing tool having a tip machining portion with a radius of curvature of 0.5 mm. FIG. 12 is an explanatory view showing a state when the abutting portion of the workpiece is machined by a conventional roller burnishing tool having a tip machining portion having a curvature radius of 1.5 mm.

  As shown in FIGS. 10 to 12, the workpiece W100 cut with the cutting tip is improved in surface roughness of the cutting surface W110, and when it is mirror-finished into a smooth surface like a mirror, roller burnishing Burnishing is performed by the tool 100 (see, for example, Patent Documents 1 and 2).

  Conventionally, as shown in FIG. 11 and FIG. 12, the roller burnishing tool 100 is attached to a processing machine such as a lathe and rotates the rollers 200 and 300 when the work surface W120 of the work W is burnished. Burnishing is performed by pressing against W100. In many cases, the rollers 200 and 300 used for burnishing the workpiece W100 having the abutting portion W130 (stepped portion) have a disk shape or an abacus ball shape. The rollers 200 and 300 of this type of roller burnishing tool 100 are formed with rounded tip processing portions 210 and 310 at the tip portions that come into contact with the workpiece W100.

JP 2000-52244 A JP 2006-26803 A

  However, when the workpiece W100 having the abutting portion W130 is burnished by the rollers 200 and 300 of the roller burnishing tool 100, the burnishing cannot be performed in the vicinity of the corner portion W140 as shown in FIGS. There was a problem that unprocessed parts W150 and W160 were generated. This is because the processed end portions 210 and 310 of the rollers 200 and 300 cannot contact the vicinity of the corner portion W140, so that the unprocessed portions W150 and W160 are formed.

The radius of curvature _{R 100} of the distal working portion 210 shown in FIG. 11, increase as the radius of curvature _{R 200} of the distal working portion 310 shown in FIG. 12, a problem that the unprocessed portion W160 also larger than the unprocessed portion W150 There was a point.

The radius of curvature _{R 100} of the roller 200 shown in FIG. 11, when the roller 200 where the smaller radius shape than the radius of curvature _{R 200} of the roller 300 shown in FIG. 12 (see FIG. 11), the unprocessed portion W150 unprocessed portion W160 Can be made smaller.

However, the roller burnishing tool 100 used in the work W100 having stepped portions like abutment portion W130, such as shown in FIG. 11, if the radius of curvature R ₁₀₀ is smaller roller, the roller in order to obtain a satisfactory processed surface Since it is necessary to slow down the feed speed of the burnishing tool 100, there has been a problem that the machining efficiency is lowered.

  FIG. 13 is a diagram showing the relationship between the radius of curvature of the tip processed portion of a conventional roller and the feed speed (0.05 mm / rev). FIG. 13A is a diagram showing the relationship between the tip processed portion having a radius of curvature of 0.5 mm. Explanatory drawing which shows the state when it processes, (b) is explanatory drawing which shows a state when a workpiece | work is processed by the front-end | tip processed part whose curvature radius is 0.2 mm.

As shown in FIG. 13B, the radius of curvature R ₁₀₀ of the tip machining portion 210 of the roller 200 shown in FIG. 13A is set to a smaller radius of curvature R ₃₀₀ and the feed speed (for example, feed speed: 0.05 mm). / Rev), a portion W170 where the roller 400 does not come into contact with the workpiece W100 is formed, and there is a problem that a processing mark (tool mark) remains on the processing surface.

  The present invention has been made in view of such a background, and even for a workpiece having an abutting portion (stepped portion), burnishing capable of suppressing the formation of an unprocessed portion and a processing mark. It is an object to provide a processing method, a roller, and a roller burnishing tool.

  In order to solve the above problems, a burnishing method according to the present invention is a burnishing method in which a roller is pressed against a surface to be processed, and the roller processes the surface to be processed and has a curvature radius of 0. A tip processing portion having an arc shape of 1 mm or more and 0.7 mm or less, and a sliding contact portion connected to the tip processing portion and slidably contacted with the processing surface. The roller is arranged and processed so that the back taper angle formed by the contact portion is 0.5 ° or more and 3 ° or less.

  According to such a configuration, the tip side of the slidable contact portion has a predetermined slidable contact range (0.5 mm or more and 2 mm or more) by arranging the roller so that the back taper angle is 0.5 ° or more and 3 ° or less and performing burnishing. .5 mm or less) to contact the surface to be processed. In addition, the roller has a tip processed portion that has a circular arc shape with a radius of curvature of 0.1 mm or more and 0.7 mm or less by processing the surface to be processed, so that the corner portion of the abutting portion (step portion) of the workpiece It is possible to provide a burnishing method capable of eliminating the formation of the unprocessed portion in the vicinity and obtaining a surface roughness better than the conventional one.

  Moreover, it is preferable that the feeding speed of the roller is 0.05 mm / rev or more and 0.20 mm / rev or less.

  According to such a configuration, the burnishing method is such that the tip processed portion and the tapered portion come into contact with the workpiece and the slidable contact range is widened, so that the feed speed is set to 0 according to the predetermined slidable range. Even when set to 0.05 mm / rev or more and 0.20 mm / rev or less, it is possible to machine the work surface of the workpiece into a smooth finished surface.

  Further, it is preferable that the rollers are arranged and processed so that a sliding contact range in which a tip side of the sliding contact portion is in sliding contact with the surface to be processed is 0.5 mm or more and 2.5 mm or less.

According to such a configuration, the back taper angle is not less than 0.5 ° and not more than 3 °, so that a suitable sliding contact range can be set.
In addition, by increasing the sliding contact range, it is easier to control the pressure applied to a soft workpiece such as aluminum than in the past.

  Further, the workpiece has the work surface, an end surface connected to the work surface and orthogonal to the work surface, and a corner portion connecting the end surface and the work surface, It is preferable to continuously process the surface to be processed and the corner portion.

  According to such a configuration, by continuously machining the corner from the work surface of the workpiece by the tip machining portion, continuous machining is performed in a state where there is no unmachined portion across the abutting portion through the work surface and the corner. can do.

  Further, the roller according to the present invention is a roller that presses and processes the surface to be processed, and has a circular arc shape with a radius of curvature of 0.1 mm to 0.7 mm by processing the surface to be processed. And a tapered portion having a cross-sectional shape so as to sandwich the tip processed portion from both sides, and the tapered portion has a sandwiching angle at which the tip processed portion is sandwiched from both sides in the tip processed portion. It is 84 degrees or more and 89 degrees or less.

  According to this configuration, the roller is formed in an arc shape having a radius of curvature of the tip processed portion of 0.1 mm or more and 0.7 mm or less, so that an unmachined portion is formed in the vicinity of the corner of the abutting portion of the workpiece. This makes it possible to perform burnishing suitable for machining a workpiece having an abutting portion. Further, the roller can be burnished even if the work surface is the outer surface, inner surface, end surface, tapered surface, or rounded surface of the workpiece. In addition, the taper portion of the roller has a pinching angle of 84 ° or more and 89 ° or less sandwiching the tip processed portion from both sides, so that the sliding contact range can be widened even with a roller having a smaller radius of curvature than the conventional one. Since it is possible, it can be processed into a good finished surface that does not leave a processing mark on the processing surface.

  In addition, the tapered portion is connected to one end of the arc shape of the tip processing portion and is slidably contacted with the surface to be processed, and the tapered portion is connected to the sliding contact portion and is inclined inward from the sliding contact portion. And a non-sliding contact portion connected to the other end of the arc shape of the tip processed portion, and a non-sliding portion connected to the non-sliding contact portion and having a gradient so as to be inward of the non-sliding contact portion. And a tangent gradient portion.

  According to this configuration, the tapered portion of the roller includes the above-described sliding contact portion, the sliding contact gradient portion, the non-sliding contact portion, and the non-sliding contact gradient portion, thereby preventing interference with the workpiece. It is possible to control and handle various workpieces.

  Moreover, the roller burnishing tool which concerns on this invention is a roller burnishing tool which presses and processes the said to-be-processed surface with the said roller of Claim 5 or Claim 6, Comprising: The holder which supports the said roller rotatably And a shank that supports the holder and is attached to the processing machine.

  The roller burnishing tool having such a configuration can burn a workpiece by supporting a roller rotatably with a holder and mounting a shank on a processing machine.

  Moreover, it is preferable that the roller burnishing tool is provided with a biasing means between the shank and the holder for biasing the holder in the distal direction to generate a processing pressure.

  According to such a configuration, an urging means for urging the holder in the distal direction is provided between the shank and the holder, so that an appropriate processing pressure can be generated.

  According to the present invention, there are provided a burnishing method, a roller, and a roller burnishing tool capable of suppressing the formation of an unprocessed portion and a processing mark even with a workpiece having a contact portion (stepped portion). be able to.

It is a side view which shows an example of the roller burnishing tool which concerns on embodiment of this invention. It is a partial expanded longitudinal cross-sectional view of the front-end part of a roller burnishing tool. It is an expansion perspective view of the roller concerning the embodiment of the present invention. It is an enlarged side view which has a partial cross section of a roller. It is explanatory drawing which shows a state when burnishing the workpiece | work which has a corner | angular part with a roller. It is a principal part expanded longitudinal cross-sectional view which shows the slidable contact range of a roller at the time of burnishing the workpiece | work with the roller whose pinching angle is 86 degrees. It is a principal part expanded longitudinal cross-sectional view which shows the slidable contact range of a roller at the time of burnishing a workpiece | work with the roller whose clamping angle is 88 degrees. It is a principal part expanded longitudinal cross-sectional view which shows the slidable contact range of a roller at the time of burnishing the workpiece | work with the roller whose pinching angle is 84 degrees. (A) It is a graph which shows the surface roughness of the workpiece | work cut with the cutting tip, (b) is a graph which shows the surface roughness of the workpiece | work burnishing processed with the roller. It is an expanded vertical sectional view which shows the conventional roller burnishing tool. It is explanatory drawing which shows a state when the contact part of a workpiece | work is processed with the conventional roller burnishing tool which has a front-end | tip processed part whose curvature radius is 0.5 mm. It is explanatory drawing which shows a state when the contact part of a workpiece | work is processed with the conventional roller burnishing tool which has a front-end | tip process part whose curvature radius is 1.5 mm. It is a figure which shows the relationship between the curvature radius of the front end process part of a conventional roller, and a feed rate (0.05 mm / rev), (a) is when a workpiece | work is processed by the front end process part whose curvature radius is 0.5 mm. Explanatory drawing which shows a state, (b) is explanatory drawing which shows a state when a workpiece | work is processed by the front-end | tip processed part whose curvature radius is 0.2 mm. It is a principal part expanded vertical sectional view which shows the slidable contact range of the roller at the time of burnishing the workpiece | work with the roller of a comparative example. (A) It is a graph which shows the surface roughness of the workpiece | work cut with the cutting tip, (b) is a graph which shows the surface roughness of the workpiece burnished with the roller of the comparative example.

  Hereinafter, an example of a burnishing method, a roller, and a roller burnishing tool according to an embodiment of the present invention will be described with reference to FIGS. 1 to 10 mainly with reference to the drawings.

  The burnishing method and the roller burnishing tool according to the present invention may have at least one roller 6 as shown in FIG. 1, and hereinafter, as an example, one roller 6 at the tip of the roller burnishing tool 1 is used. Will be described. Further, the burnishing method and the roller burnishing tool 1 and the roller 6 according to the present invention perform burnishing even if the work surface Wa of the workpiece W shown in FIG. 2 is an outer surface, an inner surface, an end surface, a tapered surface, or a rounded surface. However, a case where the workpiece W having the abutting portion Wb (stepped portion) shown in FIG. 5 is machined will be described below as an example. Before describing the roller burnishing tool 1, the workpiece W will be described.

<Work>
The workpiece W is a substantially cylindrical member made of metal that is processed by the roller burnishing tool 1. As shown in FIG. 5, the workpiece W is formed of, for example, a stepped round bar having a corner portion Wd (abutting portion Wb). The workpiece W includes a processing surface Wa, an end surface Wc connected to the processing surface Wa and orthogonal to the processing surface Wa, and a corner portion Wd where the end surface Wc and the processing surface Wa are connected. The workpiece W can be processed by the tip processing portion 6a from the processing surface Wa to the corner portion Wd and from the end surface Wc to the corner portion Wd.

<Roller burnishing tool>
A roller burnishing tool 1 shown in FIG. 2 is a burnishing (plastic deformation machining) tool that presses a roller 6 against a work surface Wa of a rotating workpiece W, crushes the work surface Wa with the roller 6, and smoothly finishes the mirror surface. The shank 2 is attached to a processing machine (not shown) such as a lathe. The roller burnishing tool 1 includes a roller 6, a holder 3 that rotatably supports the roller 6, a shank 2 that mounts the roller burnishing tool 1 on a processing machine (not shown), and the shank 2 and the holder 3. The biasing means SP and washer Z, the thrust ring 4 disposed on both front and rear surfaces of the roller 6, the plurality of needle-shaped rollers 5 fitted in the shaft holes 6g of the roller 6, and the plurality of needle-shaped rollers A roller pin 7 provided in the roller 5 and a shaft 8 for supporting the holder 3 movably on the shank 2 are provided.

<Shank>
The shank 2 is a member for supporting the holder 3 and mounting it on a processing machine (not shown). The shank 2 includes a prismatic handle main body 2a and a holder housing 2b integrally formed on the front end side of the handle main body 2a.

  The handle body 2a is a part attached to a tool post of a processing machine (not shown). The shape of the handle body 2a may be a shape that matches the tool post to be attached, and the shape is not particularly limited.

  As shown in FIG. 2, the holder housing portion 2 b is a part for mounting the holder 3. The holder accommodating portion 2b includes a holder insertion portion 2c into which the holder 3 is inserted so as to freely advance and retract by a predetermined distance, a biasing means accommodating portion 2d in which the biasing means SP and the washer Z are accommodated, and a shaft. 8 are formed with shaft support holes 2e (see FIG. 1) into which both end portions are respectively inserted, and screw holes 2f and 2g into which the screw members N1, N2, and N3 are screwed. The holder accommodating part 2b should just be inserted so that the holder 3 can move forwards or backwards, and an external appearance shape is not specifically limited.

  The holder insertion portion 2c, the urging means accommodating portion 2d, and the screw hole 2g are continuously formed at an angle of 45 °, for example, from the lower end on the front end side of the holder accommodating portion 2b toward the rear side. The holder insertion portion 2c is formed of a cavity formed in a rectangular tube shape into which the holder 3 is immersed. A shaft support hole 2e (see FIG. 1) formed on the left and right side surfaces of the holder housing portion 2b and a screw hole 2f formed on the front upper surface of the holder housing portion 2b are orthogonal to the holder insertion portion 2c. Is formed.

As shown in FIG. 2, the urging means accommodating portion 2d is formed of a cylindrical cavity having a smaller diameter than the holder insertion portion 2c. The urging means housing portion 2d communicates with the holder insertion portion 2c and the screw hole 2g, respectively.
The shaft support hole 2e (see FIG. 1) is formed from the left side surface of the holder housing portion 2b to the right side surface of the holder housing portion 2b through the center portion of the holder insertion portion 2c.
The screw hole 2f is, for example, a female screw portion that is disposed in a state in which the screw member N1 out of the two screw members N1, N2 that are continuously disposed in a straight line is screwed.
The screw hole 2g is formed obliquely downward from the rear upper end portion of the holder housing portion 2b toward the front lower end portion.

<Holder>
The holder 3 is a support member for rotatably accommodating the roller 6, and is formed in a substantially prismatic shape and is disposed in a state in which it can be advanced and retracted obliquely in the vertical direction in the holder accommodating portion 2b. The holder 3 includes a roller accommodating portion 3a in which the roller 6 and the pair of thrust rings 4 are disposed at the lower front end portion, a pin insertion hole 3b into which the roller pin 7 is inserted, a long hole 3c into which the shaft 8 is inserted, A screw hole 3d into which the screw member N1 is screwed and a spring guide 3e protruding from the center of the upper end surface of the holder 3 are formed.

The roller accommodating portion 3a is a space that is cut out at an angle of, for example, 45 ° from the front lower end to the rear upper end.
The pin insertion hole 3b is a through hole formed in the holder 3 so as to be perpendicular to the center of the roller accommodating portion 3a.
The long hole 3c is formed to be longer than the outer diameter of the shaft 8 by a predetermined dimension, for example, at an angle of 45 ° downward with respect to the circular shaft 8 as viewed in a longitudinal section. Is made movable.
The screw hole 3d is formed such that the tip of the screw member N1 screwed into contact with the outer peripheral surface of the shaft 8. The screw hole 3d is formed so as to be arranged on the same center line of the screw hole 2f when burnishing is not performed.
The spring guide 3e is a substantially cylindrical protrusion protruding from the center of the upper rear end surface of the holder 3, and the annular lower end of the biasing means SP is loosely fitted and supported.

<Energizing means>
As shown in FIG. 2, the urging means SP is an elastic member for generating a processing pressure by pushing the roller 6 back in the direction (tip direction) of the workpiece W through the holder 3. The urging means SP is composed of, for example, a compression coil spring, the lower end portion is supported by the spring guide 3e, and the upper end portion is abutted against and supported by the washer Z. The biasing means SP performs the function of adjusting the processing pressing force to absorb variations in the pre-processing such as the surface roughness of the work surface Wa of the workpiece W and making a good finished surface. For example, the biasing means SP has a deflection of 1.4 mm and a load of 230 N.

  The washer Z functions as a spring receiver whose lower surface receives the biasing means SP, and is disposed in a state where the upper surface is in contact with the tip of the screw member N3. The washer Z is advanced and retracted by rotating the screw member N3. It is a member that performs the function of adjusting the spring force (working pressure) of the biasing means SP. The washer Z is made of, for example, a disk-shaped member and is accommodated in the upper end portion in the urging means accommodating portion 2d. The washer Z is always arranged in a state where the lower surface is pressed by the biasing means SP and the upper surface is pressed by the screw member N3.

The screw members N1, N2, and N3 are, for example, hexagon socket set screws.
The screw member N1 is a fixing member that is screwed into the screw hole 3d so that the tip is in contact with the outer peripheral surface of the shaft 8 so that the shaft 8 is held by the holder 3.
The screw member N2 is a fixing member that is disposed in the screw hole 3d with its tip abutting on the screw member N1 and fixing the holder 3 to the holder accommodating portion 2b.
The screw member N3 is screwed into the screw hole 2g in a state where the tip presses the washer Z, and the biasing means SP is compressed and extended by rotating and advancing and retracting the screw member N3. A processing pressure adjusting member for adjusting the processing pressure.

  The shaft 8 is a shaft rod that supports the holder 3 by inserting the center portion into the elongated hole 3 c of the holder 3 and inserting both end portions into the left and right pivot support holes 2 e of the holder housing portion 2 b.

<Laura>
As shown in FIG. 2, the roller 6 is a rolling member for pressing the work surface Wa of the workpiece W and performing burnishing, and has a substantially abacus ball shape. The roller 6 includes a tip processing portion 6a for processing the processing surface Wa, a tapered portion 6b having a mountain-shaped cross section so as to sandwich the tip processing portion 6a from both sides, and a shaft hole into which the roller 5 and the roller pin 7 are inserted. 6g and a flat surface 6h that is disposed in a state where the thrust ring 4 is in contact with each other. The roller 6 is formed to have a size of an outer diameter of 16 mm and a thickness of 6 mm, for example.

  The roller 6 is, for example, 45 ° front-down with respect to the handle body 2a of the shank 2 in order to dispose the roller 6 in the normal direction to the rounded surface of the corner Wd (see FIG. 5) of the workpiece W. Are arranged with an inclination angle of. The roller 6 inserts the roller pin 7 into the shaft hole 6g through the roller 5, and inserts the both end portions of the roller pin 7 into the pin insertion hole 3b of the holder 3 through the thrust ring 4 so that the holder 3 Is rotatably supported by the shaft. The roller 6 is disposed so as to be elastically retractable by a predetermined dimension in the rear oblique direction together with the holder 3 when the axially supported holder 3 is immersed obliquely upward against the biasing means SP. . The feed speed (feed pitch P1) of the roller 6 shown in FIG. 5 is 0.05 mm / rev or more and 0.20 mm / rev or less.

<Advanced machining part>
As shown in FIGS. 3 and 4, the tip processed portion 6 a is a processed portion having an arc shape with a radius of curvature R ₁ of 0.1 mm to 0.7 mm. The tip processed portion 6a eliminates the unprocessed portions W150 and W160 (see FIGS. 11 and 12) that have been generated conventionally by making the radius of curvature R1 smaller than the conventional _one . In order to eliminate the unprocessed part, the radius of curvature R ₁ of the tip processed part 6a is preferably 0.2 mm or more and 0.5 mm or less, more preferably 0.2 mm or more and 0.3 mm or less. Note that when you want to smoother finish, the radius of curvature _{R 1} of the tip working portion 6a is preferably set to 0.2mm or more 0.7mm or less.

<Tapered part>
The taper portion 6b is formed of a taper formed in the tip processing portion 6a, for example, when the inclination angle of the roller is 45 °, the sandwiching angle θ2 sandwiching the tip processing portion 6a from both sides is 84 ° or more and 89 ° or less. The taper portion 6b is connected to one end of the arc shape of the tip processing portion 6a and slidably contacted with the processing surface Wa, and is connected to the slidable contact portion 6c and inside the sliding contact portion 6c with respect to the workpiece W. A sliding contact gradient portion 6d having a gradient so as to face, a non-sliding contact portion 6e connected to the other end of the arc shape of the tip processing portion 6a, and a non-sliding contact portion 6e connected to the non-sliding contact portion 6e. And a non-sliding contact gradient portion 6f having a gradient.

The sliding contact portion 6c is a linear portion in a cross-sectional view where the work W is burnished by being in contact with the work W when the work W is burnished by the roller 6. As shown in FIGS. 6 to 8, the rollers 6 are arranged so that the sliding contact ranges L1, L2, and L3 in which the tip side of the sliding contact portion 6c is in sliding contact with the processing surface Wa are 0.5 mm or more and 2.5 mm or less. And processed. Sliding range L1, as shown in FIG. 6, sandwiched at an angle θ2 is 86 °, the back taper angle [theta] 11 (.theta.1) is 2 °, when the curvature radius _{R 1} of the tip working portion 6a is 0.2 mm, 0 0.7 mm.
As shown in FIG. 7, the sliding contact range L2 is as long as 1.2 mm when the pinching angle θ2 is 88 ° and the back taper angle θ12 (θ1) is 1 ° and the taper portion 6b is loose.
As shown in FIG. 8, the sliding contact range L3 is as short as 0.5 mm when the sandwich angle θ2 is small at 84 ° and the back taper angle θ13 (θ1) is 3 °.

  Thus, the sliding contact range L1 varies depending on the back taper angle θ1. When the back taper angle θ1 is 0.5 ° to 3 °, the sliding contact range L1 is about 0.5 to 2.5 mm. That is, the sliding contact range L1 increases as the back taper angle θ1 is smaller.

  As shown in FIG. 6, the sliding contact gradient portion 6d is the gradient of the portion where the sliding contact portion 6c is formed. The angle of the sliding contact gradient portion 6d at the time of machining with respect to the work surface Wa of the workpiece W is the above-described back taper angle θ1 (θ11 to θ13). The back taper angle θ1 may vary depending on the material of the workpiece W and the like, and is 0.5 ° or more and 3 ° or less.

  The non-sliding contact portion 6e is a portion that does not contact the workpiece W when the workpiece W is burnished by the roller 6 in the tapered portion 6b. In other words, the non-sliding contact portion 6e is a portion of the sliding portion 6b near the non-sliding contact gradient portion 6f and the non-sliding contact gradient portion 6f.

  The non-sliding contact gradient portion 6f is a portion formed so as to be inclined so as not to contact the workpiece W when the workpiece W is burnished by the roller 6 in the tapered portion 6b. The angle θ4 of the non-sliding contact gradient portion 6f is formed to be small, for example, 60 °, and has an effect of escape.

As shown in FIG. 2, the shaft hole 6 g is composed of a cylindrical hollow portion drilled in the central portion of the roller 6.
The flat surface 6h is an annular flat portion formed at the left and right opening edges of the shaft hole 6g.

The thrust ring 4 is a washer-like member interposed between the inner wall of the roller accommodating portion 3 a and the left and right flat surfaces 6 h of the roller 6.
The needle-shaped roller 5 is composed of a plurality of rod-shaped members interposed between the outer peripheral surface of the roller pin 7 and the shaft hole 6 g of the roller 6. The needle roller 5 may be a needle roller bearing.
The roller pin 7 is a shaft support member for rotatably supporting the roller 6 on the holder 3 via the roller 5. The roller pin 7 is formed in a cylindrical shape, and both end portions thereof are inserted into the left and right pin insertion holes 3 b of the holder 3.

[Action]
Next, the action of the burnishing method, roller, and roller burnishing tool according to the embodiment of the present invention will be described with reference to the drawings.

  When burnishing the work surface Wa of the workpiece W with the roller burnishing tool 1 shown in FIGS. 1 and 2, the workpiece W is fixed to a rotating shaft such as a chuck of a processing machine (not shown). The roller burnishing tool 1 is fixed to a tool post or the like of a processing machine.

Next, the screw member N3 shown in FIG. 2 is rotated with a tool or the like so that the optimum surface roughness can be obtained when the pressing amount of the roller 6 is about 0.1 to 0.2 mm. The initial set load of the biasing means SP is adjusted. The screw member N3 can be adjusted by increasing or decreasing the biasing means SP by 115N, for example, by rotating the screw member N3 once in the right or left direction. For example, when the screw member N3 is rotated in the screwing direction, the biasing means SP is compressed and the spring force becomes strong, and an appropriate pressure in the direction in which the holder 3 is pushed back (arrow b direction) by the biasing means SP is applied. Be generated. Further, when the rotation operation is performed to return the screw member N3 to the direction of detachment, the biasing means SP is extended and the spring force is weakened, and the holder 3 is pushed in by the biasing means SP (in the direction of arrow a). To do.
Further, as shown in FIG. 5, the roller 6 is arranged so that the back taper angle θ <b> 1 formed by the sliding contact portion 6 c with respect to the processing surface Wa is 0.5 ° or more and 3 ° or less.

  Subsequently, the workpiece W is rotated at a peripheral speed of 200 m / min or less by rotating the processing machine. While pressing the sliding contact portion 6c of the roller 6 against the work surface Wa of the rotating workpiece W with a thrust of 30 to 230 N, the roller burnishing tool 1 is fed at a feed rate of 0.05 mm / rev to 0.20 mm / rev. Then, the workpiece W is rolled and subjected to burnishing at the tip processing portion 6a at least at the corner Wd from the processing surface Wa.

  Even when burnishing is performed at such a high feed rate, the tip processed portion 6a and the tapered portion 6b come into contact with the workpiece W, and the sliding contact range L1 is wide, and the corner portion Wd is continuously formed from the processing surface Wa. Since the processing is performed, the work surface Wa of the workpiece W can be burnished into a smooth finished surface without the portion W170 (see FIG. 13B) where the roller 6 does not contact the workpiece W.

When the roller 6 is pushed downward (arrow c direction) with respect to the workpiece W, the roller 3 receives an upward reaction force (arrow d direction) and the holder 3 tends to move obliquely upward (arrow a direction). . At that time, the roller 6 is acted on by a pushing back force by the urging means SP accommodated in the back side of the holder 3. This pushing back force becomes the applied pressure.
Then, after finishing the burnishing, the roller burnishing tool 1 is separated from the workpiece W, and the operation is finished.

Next, the effects of the burnishing method, roller, and roller burnishing tool according to the embodiment of the present invention will be described in comparison with a comparative example.
FIG. 9A is a graph showing the surface roughness of the workpiece cut by the cutting tip, and FIG. 9B is a graph showing the surface roughness of the workpiece burnished by the roller of this embodiment. . FIG. 14 is an enlarged vertical cross-sectional view of a main part showing a sliding contact range of a roller when a workpiece is burnished with a roller of a comparative example. FIG. 15A is a graph showing the surface roughness of the workpiece cut by the cutting tip, and FIG. 15B is a graph showing the surface roughness of the workpiece burnished by the roller of the comparative example.

<Roller of comparative example>
Roller 200 of the comparative example shown in FIG. 14 is a radius of curvature _{R 100} of the distal working portion 210 is 0.5 mm, with sliding range L100 of the work W100 is 0.3 mm, back taper angle θ100 is formed in 15 ° ing.
As shown in FIG. 15A, the workpiece W cut by a lathe or the like with a cutting tool of a cutting tool has a maximum surface roughness Rmax of 7.475 μm and an average surface roughness Rz of 6.889 μm. Is in a rough state.
When this workpiece W100 is burnished by the roller 200 of the comparative example shown in FIG. 14, as shown in FIG. 15B, the maximum surface roughness Rmax is 1.983 μm and the average surface roughness Rz is 1.180 μm. Finished on the surface.

<Roller of this embodiment>
As shown in FIG. 9A, as in the comparative example, the workpiece W cut by a lathe with a cutting tool of a cutting tool has a slight difference, but the maximum surface roughness Rmax is 7.470 μm, The surface was processed to an average surface roughness Rz of 6.932 μm, which was comparable to that of the comparative example.
When the workpiece W is burnished by the roller 6 having the curvature radius R ₁ of 0.2 mm described in the above embodiment, as shown in FIG. 9B, the maximum roughness Rmax of the surface is 0.460 μm and the average of the surfaces is obtained. The roughness Rz was 0.283 μm, and it was possible to finish the surface much smoother than the comparative example.

<Contrast of roller of this embodiment and roller of comparative example>
Thus, the roller 200 of the comparative example, as shown in FIG. 14, the tip machining portion 210 is formed into a simple shape only curved surface, the radius of curvature R ₁₀₀ is but as large as 0.5 mm, back taper angle Since θ100 is as large as 15 °, the sliding contact range L100 is as small as 0.3 mm and the surface roughness is large.
In contrast, roller 6 of the present embodiment, as shown in FIGS. 6 to 8, although the radius of curvature _{R 1} of the tip working portion 6a is small and 0.2 mm, back taper angle θ1 is 0.5 ° or more Since it is as small as 3 ° or less, the slidable contact ranges L1 to L3 are large and suitable from 0.5 mm to 2.5 mm. For this reason, due to the rubbing effect of the taper portion 6b slidably contacting the workpiece W, the finished surface could be processed into a dense and clean surface even if the feed rate was high.

  Further, the roller 6 was able to eliminate the occurrence of processing traces because the sliding contact ranges L1 to L3 were wider than the roller 200 of the comparative example. For this reason, since the feed speed of the roller burnishing tool 1 can be increased, the processing time can be shortened and the production efficiency can be improved.

The roller 6, by the radius of curvature _{R 1} of the tip working portion 6a is formed in a small arc shape with 0.1mm or 0.7mm or less, the raw near the corners Wd of abutment portions Wb unit W150 , W160 (see FIGS. 11 and 12) can be eliminated, and a burnishing method suitable for processing the workpiece W having the abutting Wb can be provided.

Further, the tapered portion 6b is by sandwiching angle θ2 of the distal working portion 6a is formed in the 89 ° or less 84 ° or more, even small roller 6 is the radius of curvature R ₁ than in Comparative Example, the sliding range Since L1 to L3 become wide, it can be processed into a good finished surface with no processing marks remaining on the processing surface Wa.

  As described above, the burnishing method and the roller and the roller burnishing tool according to the present embodiment include the taper portion 6b, the sliding contact portion 6c, the sliding contact gradient portion 6d, the non-sliding contact portion 6e, and the non-sliding contact gradient portion. 6f. For this reason, even if it is the workpiece | work W which has butting part Wb (step part), it can burn-process to the unfinished part W150, W160 (refer FIG.11 and FIG.12) and the beautiful finishing surface in which a process trace is not formed. it can.

[Modification]
The present invention is not limited to the above-described embodiment, and various modifications and changes can be made within the scope of the technical idea. The present invention extends to these modifications and changes. Of course.

  In the above-described embodiment, as an example of the roller 6, as illustrated in FIGS. 3 and 4, the left-right symmetric one about the tip processing portion 6 a has been described as an example. It is possible to burnishing the end surface Wc of this and the outer peripheral surface of the to-be-processed surface Wa (refer FIG. 6). That is, the roller 6 only needs to have a back taper angle θ1 formed by the sliding contact portion 6c (taper portion 6b) and the surface Wa to be processed.

  In addition, the biasing means SP shown in FIG. 2 uses a compression coil spring as an example. However, any means may be used as long as it presses the holder 3 toward the roller 6 side. A means for pressing the roller 6 using fluid pressure such as hydraulic pressure may be used.

  Further, in the above-described embodiment, the case where the processing surface Wa burns the outer surface of the workpiece W, the corner portion Wd, and the end surface Wc of the abutting portion Wb with the roller 6 has been described as an example. Even a taper surface, a round surface, or the like can be burnished.

DESCRIPTION OF SYMBOLS 1 Roller burnishing tool 2 Shank 3 Holder 6 Roller 6a Tip processing part 6b Taper part 6c Sliding contact part 6d Sliding contact gradient part 6e Non-sliding contact part 6f Non-sliding contact gradient part L1-L3 Sliding contact range R ₁ Curvature radius W Work Wa Work surface Wd Corner Wc End face θ1 Back taper angle θ2 Nipping angle

Claims (8)

A burnishing method for processing by pressing a roller on a surface to be processed,
The roller has a tip processed portion that has an arc shape with a curvature radius of 0.1 mm to 0.7 mm by processing the surface to be processed;
A sliding contact portion connected to the tip processing portion and slidably contacting the processing surface;
Arranging and processing the roller so that a back taper angle formed by the sliding contact portion with respect to the processing surface is 0.5 ° or more and 3 ° or less,
A burnishing method characterized by the above. The roller feed speed is 0.05 mm / rev to 0.20 mm / rev,
The burnishing method according to claim 1. Arranging and processing the roller so that a sliding contact range in which a tip side of the sliding contact portion is in sliding contact with the surface to be processed is 0.5 mm or more and 2.5 mm or less,
The burnishing method according to claim 1 or 2, wherein The workpiece includes the workpiece surface,
An end face connected to the work surface and orthogonal to the work surface;
A corner portion connecting the end surface and the work surface,
Processing the processed surface and the corner portion continuously by the tip processing portion;
The burnishing method according to any one of claims 1 to 3, wherein: A roller that presses and processes a work surface,
A tip processed portion having an arc shape in which the processing surface is processed and a radius of curvature is 0.1 mm or more and 0.7 mm or less;
A taper portion having a cross-sectional cross-section so as to sandwich the tip processed portion from both sides,
The taper portion has a sandwiching angle of 84 ° or more and 89 ° or less sandwiching the tip processing portion from both sides in the tip processing portion,
A roller characterized by. The tapered portion is connected to one end of the arc shape of the tip processing portion and is slidably contacted with the processing surface; and
A sliding contact gradient portion connected to the sliding contact portion and having a gradient so as to go inward from the sliding contact portion;
A non-sliding contact portion connected to the other end of the arc shape of the tip processed portion;
A non-sliding contact gradient portion connected to the non-sliding contact portion and having a gradient so as to be directed inward from the non-sliding contact portion;
The roller according to claim 5. A roller burnishing tool that presses and processes the work surface with the roller according to claim 5 or 6,
A holder for rotatably supporting the roller;
A shank for supporting this holder and mounting it on a processing machine,
Roller burnishing tool characterized by Between the shank and the holder, an urging means for urging the holder in the distal direction to generate a processing pressure is provided,
The roller burnishing tool according to claim 7.

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