JP4285008B2 - Surface processing equipment - Google Patents

Description

BACKGROUND OF THE INVENTION
[0001]
The present invention relates to a front surface machining apparatus Ru used to form the fine recesses in the surface of the workpiece, for example, moving parts which constitute the power generating device and a power transmission device such as automotive engines, transmissions and axles on the surface, or increase the operating efficiency, or it relates to the front surface machining apparatus that is used to form fine recesses (irregularities) for reducing the sliding resistance.
[0002]
[Prior art]
Conventionally, as a method of forming fine concave portions on the surface of a workpiece, there has been a method using shot blasting. This method is used, for example, when the outer peripheral surface of a piston of an automobile engine is made to have a fine uneven shape, and abrasive grains made of ceramics or the like are sprayed on the surface of a workpiece to form fine recesses on the surface. To do. However, in such a method by shot blasting, the shape of the formed recesses is random, the width and depth of the recesses are not uniform, and it is extremely difficult to form continuous recesses, that is, groove-like recesses. Have difficulty.
[0003]
On the other hand, as a method for forming a groove-like recess on the surface of the workpiece, there has been a method using a precision lathe shown in FIG. That is, one end portion of the workpiece W having a cylindrical shape is gripped by the chucking device 102 of the main shaft 101, and the other end portion of the workpiece W is rotatably held by the core pushing shaft 103. By rotating the workpiece W around the axis line and cutting the surface (outer circumferential surface) of the workpiece W by a predetermined amount with the cutting tool 104, a minute recess that is continuous in the circumferential direction on the surface of the workpiece W. Form. Then, by continuously or intermittently moving the cutting tool 104 in the axial direction of the workpiece W, as shown in FIG. 5B, groove-shaped recesses A are formed on the surface of the workpiece W at predetermined intervals. Form with.
[0004]
[Problems to be passed by the invention]
However, in surface processing using a precision lathe as described above, it is possible to form a continuous groove-shaped recess A, but in order to control the depth h of the recess A to be formed, It is necessary to accurately align the position of the tip of the cutting tool 104 with the surface of the workpiece W obtained by the pre-processing.
[0005]
However, in actual machining, the depth h of the recess A is caused by waviness of the pre-machined surface or misalignment between the spindle 101 and the workpiece W when the workpiece W is attached to the chucking device 102. It is extremely difficult to set the thickness to several μm, and the tip of the cutting tool 104 is worn as the machining progresses, so that it is difficult to control the depth h of the recess A in mass production. There was a problem to solve such problems.
[0006]
OBJECT OF THE INVENTION
The present invention has been made to solve the above-described conventional problems, and when forming a fine recess on the surface of the workpiece, a foam roller for forming the recess is used, and the surface of the workpiece is aims to reduce the influence of positioning errors of the undulation or workpiece, to suppress the variation in the depth of such a recess, providing a front surface machining apparatus that can be formed a fine recesses with high precision It is said.
[0007]
[Means for Solving the Problems]
[0008]
The surface processing apparatus of the present invention is an apparatus for forming fine concave portions on the surface of a workpiece, and the workpiece is formed on the foam roller for forming concave portions held rotatably and the foam roller in contact with the workpiece. Relative to the load generating means for applying a load in the direction, the load detecting means for detecting the load by the load generating means, the direction in which the workpiece and the foam roller are brought close to and away from each other, the rolling direction of the foam roller and the axial direction An arm for rotatably holding the foam roller, a housing for movably holding the arm in a direction intersecting the axis of the foam roller, and a load generating means between the arm and the housing. comprising a load cell is a compression coil spring and the load detecting means is characterized by controlling the moving means based on a detection signal of the load detecting means There.
[0009]
[Effects of the Invention]
[0011]
In the surface processing apparatus of the present invention, the workpiece and the foam roller held by the housing and the arm are relatively brought close to each other by the moving means, and the foam roller is brought into contact with the workpiece and the load generating means (between the arm and the housing). The workpiece is pressurized with a foam roller by an interposed compression coil spring) . At this time, the load of the load generating means (compression coil spring) detected by the load detection means ( the load cell interposed between the arm and the housing ) is Pressurize until a preset value is reached. Thereafter, the moving means relatively moves the work piece and the foam roller to roll the roller, thereby forming a fine recess on the surface of the work piece. By moving the foam roller relatively in the axial direction of the roller, fine concave portions are formed at predetermined intervals, and at this time, the moving means is controlled based on the detection signal of the load detecting means (load cell) .
[0012]
That is, in the surface processing apparatus, fine concave portions are formed on the surface of the workpiece by pressing the foam roller to which a predetermined load is applied , and the pressure applied to the foam roller is controlled. Compared with the method according to the above, the influence of the surface undulation of the workpiece, the positioning error of the workpiece, etc. is small, thereby suppressing variations in the depth of the recess. Further, since the recess is formed by rolling of the foam roller, the wear of the tool is very small.
[0013]
【The invention's effect】
According to the front surface machining apparatus of the present invention, it is possible to obtain the following effects.
When forming minute recesses on the surface of the workpiece, the recesses are formed on the workpiece by pressing the foam roller to which a substantially constant load is applied. It is possible to reduce the influence of positioning errors and the like, to suppress variations in the depth of the recesses, and to form fine recesses with high accuracy.
By selecting the shape of the tip of the outer peripheral portion of the foam roller, it is possible to form concave portions of various shapes, concave portions that are continuous in a groove shape, or discontinuous concave portions that are dotted lines. Since the recess can be continuously formed by the movement, the processing efficiency is also good.
By selecting the load to be applied to the foam roller, the depth and width of the recess can be changed.
Since the concave portion is formed along with the rolling of the foam roller, the wear of the tool is very small, the tool life can be improved, and it is suitable for mass production processing.
Since the concave portion can be formed with high accuracy, it is possible to omit the pre-processing applied to the surface of the workpiece, and it is possible to reduce man-hours and reduce costs.
Since a compression coil spring as a load generating means and a load cell as a load detecting means are provided between the arm for holding the foam roller and the housing for holding the arm, means for rotating the foam roller is unnecessary, The apparatus can be obtained in a compact and inexpensive manner, and the load of the foam roller on the workpiece can be easily changed simply by replacing the compression coil spring or the like.
Since an assembly including an arm and a housing can be handled as a tool unit, it can be easily attached to a processing apparatus such as an existing lathe, and automatic replacement by an auto tool changer can be easily handled.
[0014]
【Example】
1 to 3 are views for explaining an embodiment of the engaging Ru front surface machining apparatus according to the present invention.
The surface processing apparatus shown in FIG. 1 generally generates a load for applying a load in the direction of the workpiece W to the recess forming foam roller 1 held rotatably and the foam roller 1 in contact with the workpiece W. Means (2), load detecting means (3) for detecting the load by the load generating means (2), the direction in which the workpiece W and the foam roller 1 are brought close to and away from each other, the rolling direction and the axial direction of the foam roller 1 Moving means (101, 14) for moving relative to each other.
[0015]
The surface processing apparatus includes an arm 4 that rotatably holds the foam roller 1 and a housing 5 that holds the arm 4 so as to be movable in a direction intersecting the axis of the foam roller 1. In the meantime, the load generating means (2) and the load detecting means (3) are provided.
[0016]
The workpiece W of this embodiment is a rotating body having a circular cross-sectional shape perpendicular to the axis, and has a cylindrical shape, and a fine recess is formed on the outer peripheral surface thereof. As shown in FIG. 1B, the workpiece W is gripped at one end by a chucking device 102 of a main shaft 101 that is rotationally driven, and is moved by a core pushing shaft 103 that is arranged coaxially with the main shaft 101. The end portion is rotatably held, and rotates around the axis by the main shaft 101.
[0017]
The foam roller 1 is made of a super hard material, silicon nitride, or the like, and has high strength and toughness. Even if the workpiece W is a high hardness material such as hardened steel, fine concave portions are formed. Can be formed. Further, in the foam roller 1 of this embodiment, the outer peripheral tip is formed in an R shape with a curvature radius of 0.1 mm, and the angle of the outer peripheral tip is 60 degrees.
[0018]
The arm 4 has a bifurcated support member 6 that supports the foam roller 1, a support shaft 7 that passes through the foam roller 1 and the support member 6 and is fixed to the support member 6, and one end connected to the support member 6. A spline shaft 8 is provided, and a double-row angular ball bearing 9 is interposed between the foam roller 1 and the support shaft 7. At this time, in the arm 4, the axial direction of the foam roller 1 that coincides with the axis of the support shaft 7 (left and right direction in FIG. 1) and the arm axial direction that coincides with the axis of the spline shaft 8 (up and down direction in FIG. 1) They are orthogonal to each other.
[0019]
The housing 5 is a cylindrical member, and one end on the upper side in FIG. 1 is closed with a cap 10, and a spline nut 11 is fitted and fixed inside the other end on the lower side in FIG. 1. is there. The housing 5 is slidably inserted into the spline nut 11 so as to be slidable, and both are spline-coupled to hold the arm 4 movably only in the arm axial direction.
[0020]
A compression coil spring 2 as a load generating means is interposed between the spline shaft 8 of the arm 4 and the cap 10 of the housing 5, and the tip of the compression coil spring 2 is interposed between the cap 10 and the compression coil spring 2. A piezoelectric load cell 3 is interposed as load detecting means.
[0021]
Here, a stopper 12 having a diameter larger than the diameter of the spline shaft 8 is fixed to the other end of the spline shaft 8 located in the housing 5. The stopper 12 is made of a soft material such as urethane resin, suppresses the extension of the compression coil spring 2, reduces the impact when the spring 2 is fully extended, and prevents the arm 4 from dropping from the housing 5. To prevent.
[0022]
Furthermore, between the compression coil spring 2 and the load cell 3, an adjustment piece 13 for applying a preload to the compression coil spring 2 is interposed, and the length of the adjustment piece 13 (the length of the compression coil spring 2 in the expansion / contraction direction). The preload can be adjusted by selecting. In the load cell 3, the contact portion 3 a with the adjustment piece 13 is a protrusion having a spherical tip, so that the compression coil spring 2 can absorb the tilt in the expansion / contraction direction.
[0023]
The housing 5 holding the arm 4 is attached to a machining head 14 of a machining apparatus whose main body is not shown. In this embodiment, the machining head 14 is movable in the approaching / separating direction (X direction) and the axial direction (Z direction) with respect to the workpiece W set between the main shaft 101 and the core pushing shaft 103. In other words, in this embodiment, the processing head 14 corresponds to a moving unit that relatively moves the workpiece W and the foam roller 1 in the direction of approaching and separating from each other and the axial direction of the foam roller 1. This corresponds to moving means for relatively moving the workpiece W and the foam roller 1 in the rolling direction of the foam roller 1.
[0024]
In order to form a fine recess on the surface (outer peripheral surface) of the workpiece W by the surface processing apparatus having the above configuration, the axis of the workpiece W set between the main shaft 101 and the core pushing shaft 103 and the form roller Positioning is performed so that one axis line is substantially parallel to each other and both axis lines substantially coincide on a plane along the axis line of the arm 4 in the X direction in FIG.
[0025]
Next, the machining head 14 is advanced toward the workpiece W, and after the foam roller 1 comes into contact with the workpiece W, the machining head 14 is advanced until the load detected by the load cell 3 reaches a preset value. Let That is, when the processing roller 14 continues to advance after the foam roller 1 comes into contact with the workpiece W, the compression coil spring 2 is compressed between the arm 4 and the housing 5, and the repulsive force is applied to the foam roller 1 as a load. Since the load is detected by the load cell 3, the workpiece W can be pressurized with a predetermined load if the machining head 14 is advanced until the detected load of the load cell 3 reaches a set value. Become.
[0026]
When the set value of the load is detected as described above, the forward movement of the machining head 14 is stopped, and when the workpiece W is rotated around the axis by the spindle 1, the foam roller 1 pressed against the workpiece W is pressed. As the foam roller 1 rolls, a fine groove-like recess is formed on the surface of the workpiece W.
[0027]
At this time, in the previous positioning, if the axis of the workpiece W and the axis of the foam roller 1 are parallel to each other and the two axes coincide with each other on the same plane, one concave portion continuous in the circumferential direction. Therefore, in order to arrange a large number of recesses in the axial direction, it is necessary to repeat the advance and retreat of the machining head 14 and the intermittent movement in the lateral direction (Z direction). Therefore, in positioning, the foam roller 1 is tilted by a predetermined amount around the X axis, and the machining head 14 is moved at a constant speed in the Z direction at the same time as the formation of the recesses, so that the outer periphery of the workpiece W is spirally formed. Concave portions that are continuous with each other.
[0028]
Further, the surface of the workpiece W may be wavy due to a shape error or the like of the pre-processing, and when the workpiece W is attached to the chucking device 102 of the main shaft 101, the misalignment of both is caused. It may occur. In contrast, in those surface processing apparatus, even if the distance by the undulation or misalignment from the center of rotation of the workpiece W to the surface is changed, the arm 4 axially in accordance with a change in the distance Since it moves, a stable contact state is always obtained between the workpiece W and the foam roller 1, and the influence of the swell and misalignment is small.
[0029]
More specifically, for example, the pressing force required to form a recess having a depth of 2 μm on the surface of the workpiece W made of hardened steel has a radius of curvature of 0.1 mm at the outer peripheral end of the foam roller 1. When the compression coil spring 2 having a spring constant of 200 N / mm is used, even if the surface waviness and misalignment amount of the workpiece W is 50 μm, the fluctuation of the pressing force is 200 N. /Mm×0.05 mm = 10 N, and the variation of the depth of the recess is 10 N × 2 μm / 200 N = 0.1 μm. In addition, when forming a recessed part by cutting, if the amount of waviness and misalignment of the surface of the workpiece W is 50 μm, this becomes a variation in the depth of the recessed part as it is.
[0030]
In this way, the front surface processing apparatus described above, with respect to the surface of the workpiece W, so to form fine recesses by a substantially constant pressure of the form roller 1 a load is applied, the method according to the cutting In comparison with the above, the influence of the surface waviness of the workpiece W, the positioning error of the workpiece W, etc. is small, and the fluctuation of the pressing force of the foam roller 1 is very small. As shown in FIG. 2, fine concave portions can be continuously formed with high accuracy.
[0031]
2, there is shown a fine recesses formed by the front surface machining apparatus that by the present invention, the cemented carbide foam roller 1 in the workpiece W consisting of carburized hardened steel surface hardness HRC60 pressing The recess (A) is formed, and the surface thereof is measured with a contact type three-dimensional surface roughness meter.
[0032]
Further, FIG. 3 shows that a fine concave portion is formed on the surface of a workpiece W made of carburized and hardened steel using two types of cemented carbide foam rollers 1 having a curvature radius of 0.1 mm and 0.5 mm at the outer peripheral end. This shows the relationship between the load and the depth of the recess when forming. The processing conditions in this case are: the diameter of the foam roller 1 is 63 mm, the diameter of the workpiece W is 40 mm, the rotation speed of the main shaft 101 is 30 revolutions per minute, and the feed amount in the Z direction of the foam roller 1 is one revolution of the workpiece. Per mm.
[0033]
Front surface machining apparatus of the embodiment, since the fine recesses can be formed with high precision, it is possible to omit the processing before subjecting the surface of the workpiece W, and reduce and cost of labor To get. Moreover, if the shape of the front-end | tip part of the outer peripheral part of the foam roller 1 is selected, the recessed part of various shapes, the recessed part continuous in the shape of a groove | channel, or a discontinuous recessed part of dotted line shape can be formed, and it gives to the foam roller 1 If the load is selected, the depth and width of the recess can be changed. In any case, the recess is continuously formed by the rolling of the foam roller 1, so that the processing efficiency is good. Furthermore, since the concave portion is formed as the foam roller 1 rolls, the wear of the tool becomes very small, and the tool life can be improved.
[0034]
Moreover, those surface machining apparatus, as the material of the workpiece, not only soft metal such as aluminum, can be applied to materials such as carbon steel or alloy steel and their hardening material, for example, a wide Fine concave portions can be formed on various automobile parts. Further, unlike the shot blasting method, the groove-shaped concave portions can be formed at an equal pitch, and conversely, the pitch can be made variable.
[0035]
Moreover, those surface processing apparatus by sending a detection signal from the load cell (load detecting means) 3 to the control unit of the processing apparatus can start the processing automatically, this time, based on a detection signal Thus, a substantially constant load can be maintained without performing feedback control, so that fine concave portions can be efficiently formed.
[0036]
Further, in the surface processing apparatus, the foam roller 1 is preferably made of a hard material such as carbide, silicon nitride, and alumina. Can be formed efficiently. Further, it is desirable that the outer peripheral end of the foam roller 1 has an R shape with a curvature radius of 0.05 to 0.5 mm. This is because if the radius of curvature is less than 0.05 mm, continuous machining becomes difficult due to chipping of the tip portion, and if the radius of curvature exceeds 0.5 mm, the required load increases and the device becomes larger. This is because the bending of the workpiece W during processing becomes large and high-precision processing becomes difficult. That is, by setting the radius of curvature of the outer peripheral end of the foam roller 1 to 0.05 to 0.5 mm, it is possible to form a fine recess in the high hardness material with a small load.
[0037]
Further, the surface processing apparatus includes an arm 4 that rotatably holds the foam roller 1, and a housing 5 that holds the arm 4 movably in a direction intersecting the axis of the foam roller 1. Since a compression coil spring (load generating means) 2 and a load cell (load detecting means) 3 are provided between them, no means for rotationally driving the foam roller 1 is required, and hydraulic pressure or air pressure is used for the load generating means. Compared to the case, the pump and the piping and the special seal structure are not required, and the apparatus can be obtained in a compact and inexpensive manner. Also, by simply replacing the compression coil spring 2 and the adjusting piece 13, the workpiece W can be obtained. The load of the foam roller 1 can be easily changed.
[0038]
And in the said surface processing apparatus, since the assembly body provided with the arm 4 and the housing 5 can be handled as a tool unit as shown to Fig.1 (a), attachment to processing apparatuses, such as the existing lathe, is easy. The automatic change by the auto tool changer can be easily dealt with.
[0039]
Further, in the surface processing apparatus, since the double-row angular contact ball bearing 9 is interposed between the foam roller 1 and the arm 4, the radial direction of the foam roller 1 with respect to the arm 4 with one bearing (9). Further, the movement in the thrust direction can be restricted, which makes it possible to make the apparatus more compact, reduce the interference in the processing apparatus, and widen the processing application range.
[0040]
Further, in the surface processing apparatus, the arm 4 and the housing 5 are coupled so as to be movable only in the arm axis direction (X direction) by the spline coupling of the spline shaft 8 and the spline nut 11. Shaking in the direction in which the foam roller 1 is twisted can be suppressed, and the arm 4 can be moved smoothly, so that the followability of the foam roller 1 with respect to the surface of the workpiece W increases, Realize further improvement in accuracy.
[0041]
In the above-described embodiment, the workpiece W having a cylindrical shape is illustrated. However, the shape of the workpiece is not particularly limited, and a workpiece having a flat surface or a disk constituting a continuously variable transmission. As described above, a fine recess can be formed in a rotating body whose radius changes in the axial direction (a cross-sectional shape perpendicular to the axis forms a circle).
[0042]
Further, engagement Ru front surface machining apparatus of the present invention, so as to maintain the value of load is set in advance in the load detecting unit load generating means is detected by the (load cell 3) (compression coil spring 2), and the workpiece W A fine recess may be formed on the surface of the workpiece W while controlling the relative position of the foam roller 1.
[0043]
In other words, feedback control of the machining head 14 in the machining apparatus, which is the moving means, based on the detection signal of the load detection means almost eliminates variations in the depth of the formed recess and forms a more accurate recess. In addition, even if the workpiece's external shape is unknown or the size or shape of each workpiece is different, the workpiece can be processed without special positioning or correction. It is possible to follow the surface and form a fine recess with high accuracy.
[0044]
Further, engagement Ru front surface machining apparatus of the present invention, as the load of the load detecting means load generating means is detected by the (load cell 3) (compression coil spring 2) periodically changes at a preset value, to be processed You may make it form a fine recessed part in the surface of the workpiece W, controlling the relative position of the thing W and the form roller 1. FIG. In this way, by changing the load of the foam roller 1 on the workpiece W, it is possible to easily form a fine recess whose depth continuously changes on the surface of the workpiece W.
[0045]
Further, engagement Ru front surface machining apparatus of the present invention, as shown in FIG. 1 (b), while supplying the oil mist OM on at least one of the outer peripheral portion of the surface and form roller 1 of the workpiece W, the workpiece It is also effective to form fine concave portions on the surface of the object W. Thereby, further improvement in durability of the foam roller 1 and rust prevention of the workpiece W can be realized, and oil can also be supplied to the bearing (9) of the foam roller 1.
[0046]
FIG. 4 is a view showing another embodiment of the surface processing apparatus according to the present invention. In the illustrated surface processing apparatus, a support member 22 is provided on a holder 21 that can be mounted on a processing head (not shown) via a load cell 3 as a load detection means, and a rotating shaft is provided on an extension 22 a of the support member 22. A base end portion of the swing arm 24 is connected via a pivot 23. The foam roller 1 is rotatably provided at the tip of the swing arm 24 via the support shaft 7 and the double-row angular ball bearing 9, and between the support member 22 and the swing arm 24, A compression coil spring 2 is interposed coaxially with the axis of the holder 21 as a load generating means for applying a load in the direction of the workpiece to the foam roller 1 in contact with the workpiece W. Even in such a surface processing apparatus, the same operations and effects as in the previous embodiments can be obtained.
[0047]
In each of the above embodiments, a load generating mechanism using a fluid pressure such as oil or air is adopted as a load generating means in addition to a compression coil spring, and a device such as a pressure sensor is adopted as a load detecting means in addition to a load cell. However, if the compression coil spring is used as the load generating means and the load cell is used as the load detecting means as in each of the above embodiments, the device configuration becomes compact and simple, and the manufacturing cost is reduced. Etc. can be realized.
[0048]
The moving means may be any means that moves the workpiece and the foam roller relative to each other in the direction of approaching and separating from each other, the rolling direction of the foam roller, and the axial direction (the direction along the surface of the workpiece). In either direction, either one can be fixed or both can be moved, and the present invention is not limited to the above embodiments.
[Brief description of the drawings]
It is a cross-sectional view illustrating one embodiment of a front surface machining apparatus of the present invention; FIG (a) and a side view showing a working state (b).
Is a diagram showing a measurement result of the surface shape of the workpiece to form a recess by the front surface machining apparatus of the present invention; FIG.
[Figure 3] This when forming the recess by the front surface machining apparatus of the invention, is a graph showing the depth of the relationship between the load and the recess.
FIG. 4 is a side view for explaining another embodiment of the surface processing apparatus of the present invention.
5A is a side view for explaining a conventional surface processing apparatus, and FIG. 5B is a cross-sectional view showing the vicinity of the surface of a workpiece.
[Explanation of symbols]
A Concave W Workpiece 1 Foam roller 2 Compression coil spring (load generating means)
3 Load cell (load detection means)
4 Arm 5 Housing 8 Spline shaft 11 Spline nut 14 Processing head (moving means)
101 Spindle (moving means)

Claims (5)

A device for forming fine recesses on the surface of a workpiece, which includes a recess forming foam roller that is rotatably held, and a load that applies a load in the direction of the workpiece to the foam roller that contacts the workpiece. A generating means, a load detecting means for detecting a load by the load generating means, and a moving means for relatively moving the workpiece and the foam roller in a direction in which the workpiece and the foam roller approach and separate from each other, a rolling direction of the foam roller, and an axial direction,
An arm that rotatably holds the foam roller and a housing that holds the arm movably in a direction that intersects the axis of the foam roller, and a compression coil spring that is a load generating means and load detection between the arm and the housing A load cell as a means,
A surface processing apparatus for controlling a moving means based on a detection signal of a load detecting means.   The surface processing apparatus according to claim 1, wherein the workpiece is a rotating body, and the moving means includes a main shaft that holds the workpiece and rotates it around an axis.   The surface processing apparatus according to claim 1, wherein an outer peripheral end of the foam roller has an R shape with a curvature radius of 0.05 to 0.5 mm.   The surface processing apparatus according to any one of claims 1 to 3, wherein a double-row angular ball bearing is interposed between the foam roller and the arm.   The surface processing apparatus according to any one of claims 1 to 4, wherein the arm and the housing are coupled so as to be movable only in the arm axis direction by spline coupling.

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