JP3241358B2 - Apparatus for buffing metal pipe outer peripheral surface and buffing method using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to motorcycle mufflers, vehicles,
The present invention relates to a buff finishing apparatus and a buff finishing method capable of providing an outer peripheral surface of a metal tube used for exteriors of ships, building structures and the like with excellent gloss and for final finishing.

[0002]

BACKGROUND ART Metal tubes used for mufflers of motorcycles and exteriors of vehicles, ships, building structures, and the like include:
For decorative purposes and the like, a high degree of smoothness and glossiness are required to such an extent that scratches and the like cannot be recognized by human eyes. It is becoming more sophisticated. For that purpose, it is necessary to finish the outer peripheral surface of such a metal tube by a high degree of polishing.

[0003] Conventionally, as a polishing apparatus for giving a gloss to the outer peripheral surface of a metal pipe such as steel or aluminum alloy and finishing the metal pipe, a metal wheel, which is a workpiece, is polished with a grinding wheel, an adjusting wheel, and a receiving wheel. 2. Description of the Related Art There is known a centerless grinding machine (centerless) in which a cylindrical outer peripheral surface of a metal tube is supported by a plate and polished. However, with such a centerless grinding machine, it was not possible to obtain such a high degree of smoothness and glossiness, and it was necessary to rotate and move the metal tube with a grinding wheel or an adjusting wheel. Because of this, only long metal tubes can be machined, and therefore, for example, the finish polishing of motorcycle mufflers, etc., is almost always adopted for reasons of required accuracy and operating mechanism. I couldn't do it.

On the other hand, US Pat. No. 5,658,187 proposes a polishing apparatus having a structure in which the direction of the rotation center axis of a polishing roll is swung about one axis and abuts against the outer peripheral surface of a metal tube. . However, even with this polishing apparatus, since it is necessary to rotate and axially move the metal tube with a guide roll or a transport roll, only a long metal tube can be machined. Had the same problem. Also, with regard to the smoothness and glossiness of the finished surface, it is possible to obtain higher performance than a centerless grinding machine, but with the swing of the polishing roll, polishing on the outer peripheral surface of the metal tube body There is a problem that the roll is likely to flap (vibrate) and the state of contact of the polishing roll with the metal tube is difficult to stabilize. Thus, the required accuracy level has not yet been achieved.

Japanese Patent Application Laid-Open No. 54-82791 discloses that an outer peripheral surface of a tubular body is supported by rollers from both lower sides, and a center axis is positioned at both axial ends of the tubular body. There is disclosed a method of performing mirror polishing with an abrasive that is rotationally driven with an orthogonal axis extending on a plane orthogonal to the axis as a rotation center axis. However, in such a mirror polishing method, since the accuracy of the mirror polishing is greatly affected by the state of the foundation of the tube surface before the mirror polishing, it is difficult to obtain the target processing accuracy, and in addition, There is a problem that abrasive powder or the like is caught between the roller supporting the tube and the surface of the tube, and the surface of the tube is easily damaged, and it has been difficult to stably obtain the surface of the tube with sufficient accuracy. It is.

[0006] Therefore, in the related art, the finish processing of the outer peripheral surface of a muffler of a motorcycle, for example, has been performed exclusively by a manual operation by a human. Specifically, a buffing machine or the like is used to extend in a horizontal direction. The outer peripheral surface is manually rotated and axially fed while the operator directly contacts the outer peripheral surface of the muffler held by hand against the polishing wheel or buff wheel driven to rotate around the rotation center axis. Finish processing was performed.

However, such work by humans is
It is unavoidable that it is extremely difficult to improve the production efficiency and the cost becomes large. In addition, since extremely high skill is required for the work, labor shortage and the like may become a serious problem, and the quality of the product may vary depending on the skill level, and it is difficult to secure stable quality. There was a big problem.

[0008] In addition, since a large amount of dust such as grinding waste is generated by the polishing operation, the working environment is liable to be extremely deteriorated, and the incidence of pneumoconiosis may be increased. Extremely serious problems were also feared.

[0009]

Here, the present invention has been made in view of the above-mentioned circumstances, and a problem to be solved is to provide a method for mechanically controlling the outer peripheral surface of a metal tube body without manual operation. A new buff finisher and a new buff finish method, which can give the final finish with excellent smoothness and gloss, and can also stably process short metal tubes such as motorcycle mufflers. To provide.

[0010]

The following describes aspects of the present invention made to solve the above-mentioned problems. In addition, each aspect described below can be adopted in any combination. Further, aspects or technical features of the present invention are described in the entire specification and the drawings without being limited to those described below.
Alternatively, it should be understood that the present invention is recognized based on the inventive concept that can be understood by those skilled in the art from the descriptions thereof.

First, the first aspect of the present invention relating to a buff finishing device for an outer peripheral surface of a metal tube is as follows: (a) holding the both ends in the axial direction of the metal tube and rotating the metal tube around a central axis; Tube support means for supporting the tube as much as possible; (b) tube rotation drive means for driving the metal tube supported by the tube support means to rotate about a central axis; and (c) outer peripheral surface of the metal tube. Grinding wheel support means for rotatably supporting a grinding wheel for performing rough finishing with respect to the metal tube so as to be relatively movable in an approaching / separating direction with respect to the metal tube; and (d) polishing supported by the grinding wheel supporting means. A grinding wheel rotation drive means for rotating the wheel about its rotation center axis; and (e) a grinding wheel contact for bringing the outer peripheral surface of the grinding wheel into contact with the outer peripheral surface of the metal tube at a substantially constant pressure. Contact pressure adjusting means; (f) the metal tube and the grinding wheel are placed inside the metal tube; (G) a buff wheel for performing a final finish on the outer peripheral surface of the metal tube so that the buff wheel can rotate relative to the metal tube body independently of the grinding wheel; Buffing wheel supporting means for supporting the buffing wheel so as to be relatively movable in the approaching / separating direction; (h) buffing wheel rotation driving means for driving the buffing wheel supported by the buffing wheel supporting means around its rotation center axis; i) a buff wheel contact pressure adjusting means for bringing the outer peripheral surface of the buff wheel into contact with the outer peripheral surface of the metal tube at a substantially constant pressure; and (j) the metal tube and the buff wheel. Buffing wheel feed means for causing relative movement in the direction of the center axis of the metal tube, (k) an inclination angle of the rotation center axis of the grinding wheel with respect to the metal tube, and a rotation center axis of the buffing wheel with respect to the metal tube. The tilt angle can be adjusted and set independently of each other. Angle adjusting means for setting the rotation center axis of the grinding wheel and the rotation center axis of the buff wheel in directions different from each other and in different directions with respect to the center axis of the metal tube, respectively. While rotating the grinding wheel and the buff wheel around their respective rotation center axes so as to sequentially contact the outer peripheral surface of the metal tube, the metal tube and the grinding wheel are rotated. Further, the buff wheel is relatively moved in the direction of the center axis of the metal tube, so that the outer peripheral surface of the metal tube is rough-finished and finally finished sequentially.

In the buffing device having the structure according to the present embodiment, (1) the rotation center axis of the grinding wheel for rough finishing and the rotation center axis of the buffing wheel for final finishing are both formed of a metal tube. (2) The rotation center axis of the grinding wheel and the rotation center axis of the buff wheel can be set in directions different from each other. By the synergistic effect of (2), the outer peripheral surface of the metal tube can be stably buffed with extremely excellent smoothness and glossiness.

[0013] The reason why such a technical effect is exhibited has not yet been sufficiently clarified, and it is not the purpose of the present invention to clarify the reason. According to the results of the examination, (a) the direction of rough finishing by the grinding wheel and the direction of rough finishing by the buff wheel are both
By making the rotation direction different from that of the metal tube, it is possible to prevent the generation of circumferential flaws on the tube, and (b) the circumferential flaw is visually observed on the outer peripheral surface of the cylindrical tube. The fact that the scratches in the axial direction and the inclination direction are hard to be visually recognized, and (c) the rough finishing machining direction and the final finishing machining direction are made different from each other, It is presumed that this is based on a synergistic effect such as that processing scratches at the finish can be reduced offsetly.

Moreover, in the buff finishing device having the structure according to this aspect, the contact pressure of the grinding wheel and the buff wheel against the metal tube is stabilized by keeping the inclination angle of the grinding wheel and the buff wheel constant. And the buffing wheel does not dance unstably against the metal tube, and the polishing direction can be maintained in a stable manner, thereby improving the precision of the polished surface. Stability can be achieved.

One of the features of the buffing device having the structure according to the present embodiment is that the metal tube is supported at both ends in the axial direction without supporting the outer peripheral surface of the metal tube with a roll or the like. . In this way, it was possible to completely avoid the occurrence of scratches and the like caused by the biting of the abrasive powder or the like between the contact surface between the outer peripheral surface of the metal tube and the support roll or the like. Thus, a more polished surface can be obtained more stably. Moreover, since the metal tube can be firmly supported at both ends in the axial direction, for example, a motorcycle muffler is buffed in a final step in a finished state after a muffler is incorporated therein. It is possible to finish, and thereby, the occurrence of scratches at the time of work such as installation of a muffler is also removed,
There is also an advantage that occurrence of defective products can be minimized.

According to the buffing device having the structure according to the present embodiment, the buffing of the motorcycle muffler, which was conventionally performed only by hand for accuracy reasons, is performed by machining. And the manual buffing, which conventionally required 5 minutes or more, could be realized with the same or better accuracy by machining in only 2 to 3 minutes. It is clear from the above fact that the buff finishing apparatus according to this embodiment has a remarkable technical effect.

In addition, when buffing a stainless steel tube, such as a motorcycle muffler, a base tube obtained by bending a flat plate formed by rolling or the like with a roll or a press and performing butt welding is used. As it is, it is possible to use it as a product as it is by setting it in the buffing finisher according to this embodiment without applying any special groundwork, and performing rough finishing with a grinding wheel and buffing with a buffing wheel. To a certain extent, it can be finished to a mirror-like surface.

Further, in the buff finishing device having the structure according to this aspect, the inclination adjusting means appropriately adjusts and sets the inclination angle of each rotation center axis of the grinding wheel and the buff wheel with respect to the center axis direction of the metal tube. Since it is possible to do so, the material of the metal tube, the grinding wheel and the buff wheel,
The inclination direction of the rotation center axis of the grinding wheel and the buffing wheel so that a high-precision pipe finished surface can be obtained according to the rotational speed and the relative rotation ratio of the metal tube and the grinding wheel and the buffing wheel. Can be changed and adjusted as appropriate to set an optimum state.

In this embodiment, the tube supporting means is
It is sufficient that the metal tube is held at both ends in the axial direction without contacting the outer peripheral surface serving as the buffing surface of the metal tube, for example, a pair of supports rotatably supported on the same central axis. A mechanism in which the shaft is relatively moved in the axial direction by a cylinder mechanism or the like, and a fixed support is provided between the supporting shafts with both ends in the axial direction of the metal tube being held, or a rotatable support is provided on the same central axis. This can be advantageously realized by a mechanism or the like in which a pair of support shafts are fixedly attached to and supported by both ends in the axial direction of the metal tube body by air suction, screw fixing, or the like. In particular, in the present aspect, the metal tube body is not held in a cantilever state on only one side in the axial direction, but is held at both end portions in the axial direction, so that the outer peripheral surface serving as a processing surface is supported by a roller or the like. Thus, the metal tube can be stably supported on one central axis against the contact pressure of the grinding wheel and the buff wheel.

Further, in this embodiment, the tube body rotation driving means, the grinding wheel rotation driving means, and the buff wheel rotation driving means include:
For example, those using various electric motors can be suitably adopted, and more preferably, those whose rotational speed can be adjusted and set according to the material and outer diameter of the metal tube, required finishing accuracy, and the like. Is used. Furthermore, in the present embodiment, the material and structure of the grinding wheel and the buff wheel should be appropriately selected according to the material of the metal tube to be processed and the required processing accuracy, and are particularly limited. For example, as the buffing wheel, any of known cloth buffs using cotton, hemp, or the like may be used, while as the polishing wheel, in addition to the cloth buffing of the same material as the buffing wheel, polishing may be performed. Various known polishing disks using paper, a sintered material, or the like can be employed.

According to a second aspect of the present invention, there is provided a buffing device having a structure according to the first aspect, wherein the angle adjusting means includes a rotation center axis of the polishing wheel and a rotation of the buffing wheel. Each of the central axes is inclined at a range of ± 20 degrees with respect to a plane perpendicular to the central axis of the metal tubular body and set at different inclination angles from each other. According to such an embodiment, polishing scratches caused by a grinding wheel or a buff wheel on the metal tube body are more difficult to be recognized, and a more accurate buffing can be efficiently performed. In this embodiment, more preferably, both the rotation center axis of the grinding wheel and the rotation center axis of the buff wheel are within ± 10 degrees with respect to a pipe axis orthogonal plane orthogonal to the center axis of the metal pipe body. The inclination is set.

Further, a third aspect of the present invention is a buff finishing device having a structure according to the first or second aspect, wherein the angle adjusting means includes a rotating center axis of the grinding wheel and the rotating center axis. The rotation center axis of the buff wheel is set so as to be inclined to the opposite sides with respect to a tube axis orthogonal plane orthogonal to the center axis of the metal pipe body. According to such an embodiment, polishing scratches caused by a grinding wheel or a buff wheel on the metal tube body are more difficult to be recognized, and a more accurate buffing can be efficiently performed.

According to a fourth aspect of the present invention, there is provided a buffing apparatus having a structure according to any one of the first to third aspects, wherein the metal tube is arranged in a central axis direction of the metal tube. And the base member supports the grinding wheel and the buff wheel together, and moves the grinding wheel and the buff wheel relative to the metal tube body in the axial direction. Thereby, the polishing wheel feeding means and the buff wheel feeding means are constituted, and the polishing wheel and the buff wheel are independently moved relative to the base member in the approaching / separating direction with respect to the metal tube. The grinding wheel support means and the buff wheel support means are provided by providing a guide mechanism for moving. According to this aspect, by moving the base member in a direction parallel to the central axis of the metal tube, the relative movement between the grinding wheel and the buff wheel and the metal tube by the grinding wheel feeding means and the buff wheel feeding means. Can be advantageously realized. Further, the grinding wheel and the buff wheel are relatively moved independently of each other in the approaching / separating direction with respect to the metal tube by the guide mechanism. Rough finishing and final finishing can be performed.

In the fourth aspect, it is particularly preferable that the center axis of the metal tube is fixed in the axial direction and the direction perpendicular to the axis, while the center axis of rotation of the grinding wheel and the buff wheel is set in the metal tube. In the direction of the central axis and in the direction of approaching / separating from the metal tube. According to such a structure, it is not necessary to move a long metal tube at the time of machining, so that the operation of the device at the time of machining and stabilization of machining accuracy can be more advantageously achieved. When the central axis of the metal tube is fixedly supported, the metal tube and the rotation drive system around the central axis are supported so that the metal tube can be moved and positioned and fixed in the central axis direction of the metal tube. The pipe support which is set can be suitably adopted. By providing such a position-adjustable tube support, for example, according to the length of the metal tube or the like, before processing, the metal tube is moved in the center axis direction with respect to a grinding wheel or a buff wheel. Relative positioning can be performed at an advantageous position, whereby workability can be improved.

In the present embodiment, as the contact pressure adjusting means, for example, the contact pressure on the metal tube of a grinding wheel or a buff wheel is directly measured by various sensors such as a strain gauge, a load cell, and a piezoelectric element. A contact pressure control mechanism that adjusts the relative position in the approaching / separating direction between the grinding wheel or the buff wheel and the metal tube body by feedback control or the like so that a predetermined contact pressure is set can be adopted. In addition, after the grinding wheel or the buff wheel abuts on the metal tube, the relative movement distance in the further approaching direction of the two can be set directly or on the transmission path of the abutment pressure. Feedback control of the relative position in the approach / separation direction between the grinding wheel or buffing wheel and the metal tube so that the relative movement distance after the contact is within the preset range is measured indirectly by the amount of deformation, etc. Contact pressure control mechanism It may be employed in.

That is, the contact pressure control mechanism is, for example, a buff finishing device having a structure according to any one of the first to fourth aspects, wherein the polishing wheel supporting means is provided for the metal tube. By providing a grinding wheel pressing member that is driven and displaced in the approaching direction, by applying a driving force in the approaching direction of the grinding wheel pressing member to the metal tube body via the grinding wheel abutting elastic member to the grinding wheel. While the grinding wheel is in contact with the metal tube, the position of the grinding wheel pressing member is adjusted such that the elastic deformation of the grinding wheel contacting elastic member becomes a preset target value. Thus, it can be advantageously realized by the fifth aspect of the present invention. Alternatively, the buffing device having a structure according to any one of the first to fifth aspects, wherein the buffing wheel supporting means includes a buffing wheel pressing member that is driven and displaced in a direction approaching the metal tube. The buff wheel is brought into contact with the metal tube by applying a driving force in the approach direction of the buff wheel pressing member to the metal tube via the buff wheel contact elastic member. On the other hand, according to the sixth aspect of the present invention, the position of the buff wheel pressing member is adjusted such that the elastic deformation amount of the buff wheel contacting elastic member becomes a preset target value. , Can be advantageously realized.

In the buff finishing device having the structure according to the fifth or sixth aspect of the present invention, the grinding wheel or the buff is connected to the grinding wheel or the buff wheel contacting elastic member. Since the contact force to the metal tube is exerted on the car, even if the position of the processing surface of the metal tube suddenly changes due to, for example, a deformed shape of the metal tube, the polishing vehicle contact elastic member or the like can be used. The elastic deformation of the buff wheel contacting elastic member can substantially cope with no time delay, and the processing state of the metal tube by the grinding wheel or the buff wheel can be stably maintained.

Moreover, since the contact force can be measured based on the amount of elastic deformation of the polishing wheel contacting elastic member and the buff wheel contacting elastic member, even if the surface shape of the metal tube changes, There is no need to reset the abutment reference point of the grinding wheel or buffing wheel on the metal tube, and the desired abutting force can be continuously measured and controlled. In short, in the fifth or sixth aspect of the present invention, a polishing wheel contacting elastic member or a buff wheel contacting elastic member disposed on a transmission path for exerting a contact force on a polishing wheel or a buffing wheel. By monitoring the amount of elastic deformation of the grinding wheel and adjusting the position of the grinding wheel pressing member or the buff wheel pressing member by position control or driving force control so that the amount of elastic deformation becomes a target value, expensive and small pressure The grinding wheel and the buff wheel can be more stably controlled with a simpler structure than a contact pressure control by a pressure sensor using a piezo or the like, which is difficult to detect the value.

In this embodiment, as the polishing wheel contacting elastic member or the buffing wheel contacting elastic member, any one having elasticity in which the Hook's law is satisfied in the contact force action area is used for control. It is desirable from the viewpoint of easiness and the like. For example, a metal spring or a resin spring such as a coil spring or a disc spring having an appropriate spring coefficient, or a rubber elastic body having an appropriate elastic coefficient is suitably employed. Further, as a driving means for adjusting the position of the grinding wheel pressing member and the buff wheel pressing member,
For example, in addition to a drive system using an electric motor and a transmission mechanism such as a gear or a screw, a drive system using a cylinder mechanism or the like can be suitably used.

In the feedback control in the fifth or sixth aspect, for example, the elastic deformation amount of the polishing wheel contacting elastic member or the buff wheel contacting elastic member detected by a sensor or the like is set in advance. The target value is compared as an electric signal, and based on the difference, a feedback control device that outputs a control signal for adjusting the position of the grinding wheel pressing member or the buff wheel pressing member to the driving unit,
It can be realized advantageously. There, a preset target value for the amount of elastic deformation of the polishing wheel contacting elastic member and the buff wheel contacting elastic member is set in a predetermined stroke range, and when the target stroke is out of the set stroke range, It is desirable to adjust the positions of the grinding wheel pressing member and the buff wheel pressing member. By setting the target value of the amount of elastic deformation of the elastic member for polishing wheel contact and the elastic member for buff wheel contact with a predetermined allowable range (set stroke range), the pressing member for polishing wheel and the pressure for buff wheel contact are set. The control of the members is facilitated and the components are stabilized. Also, by adopting such a feedback control device, for example,
When the elastic deformation of the polishing wheel contacting elastic member or the buff wheel contacting elastic member exceeds the set stroke range, the position of the polishing wheel contacting pressing member or the buffing wheel contacting pressing member is set in advance. By changing the contact force by a predetermined amount, it is possible to adjust the contact force by taking into account the control form of the contact force in a feedforward manner, thereby improving the followability when the contact force changes rapidly. Is also possible.

In the fifth or sixth aspect,
The measurement of the elastic deformation of the elastic member for abrading wheel contact or the elastic member for buff wheel contact can be performed, for example, by using a conventionally known distance such as a potentiometer, a differential transformer, a semiconductor magnetoresistive element displacement meter, or a photo-electric element displacement meter. Although it is possible to directly measure using a sensor, the amount of elastic deformation of the polishing wheel contacting elastic member or the buff wheel contacting elastic member can be set to the upper limit of the set stroke range using a limit switch or the like. By detecting the points that have exceeded and the points that have exceeded the lower limit, the amount of elastic deformation of the polishing wheel contacting elastic member and the buff wheel contacting elastic member is measured, and the amount of elastic deformation of those elastic members is set within the set stroke range. In this case, the positions of the grinding wheel pressing member and the buff wheel pressing member may be changed by a predetermined amount set in advance.

According to a seventh aspect of the present invention, there is provided a buffing apparatus having a structure according to any one of the first to sixth aspects, wherein the tube rotation driving means, the grinding wheel rotation driving means, By controlling the polishing wheel feed means, the buff wheel rotation drive means, and the buff wheel feed means, respectively, the rotation speed of the metal tube body, the rotation speed of the buff wheel, the grinding wheel and The present invention is characterized in that drive control means capable of presetting the relative movement speed of the buff wheel and the metal tube body in the axial direction in a pattern is provided. In the finishing device having the structure according to the present aspect, the polishing conditions by the grinding wheel or the buff wheel are appropriately and easily adjusted and set according to the material of the metal tube and the required processing accuracy. Therefore, it is possible to easily cope with a wider range of required characteristics. In addition, for example, by performing reciprocating relative movement of the grinding wheel or buffing wheel a plurality of times in the axial direction with respect to the metal tube body, when performing at least one of rough finishing and final finishing a plurality of times, different polishing conditions for each time. Can also be set. In the case where polishing is performed a plurality of times (a plurality of strokes) by a polishing wheel or a buff wheel, it is desirable that the polishing wheel or the buff wheel be brought into contact with the metal tube only in the same feed axis direction to perform the polishing. Thereby, generation of polishing marks on the outer peripheral surface of the metal tube can be more advantageously reduced or prevented.

According to an eighth aspect of the present invention, there is provided a buffing apparatus having a structure according to any one of the first to seventh aspects, wherein an outer periphery of the metal tube body with which the buffing wheel abuts. An air supply means for supplying cooling air to the surface and / or the inner peripheral surface is provided. In the buffing finishing device having the structure according to the present aspect, the heating of the metal tube at the buff polishing portion is reduced or avoided, and thermal discoloration is prevented, so that the quality of the metal tube is advantageous. And the processing efficiency can be improved by increasing the processing speed. It is to be noted that as the cooling air, room temperature air or the like can be employed, but it is preferable to employ air having a temperature lower than room temperature, for example, cooling air having a temperature of about 0 ° C. or lower. Further, when cooling air is supplied to the outer peripheral surface of the metal tube, the polishing powder can be blown off by the cooling air, thereby contributing to further improvement in polishing accuracy.

Further, the first aspect of the present invention relating to a method for buffing an outer peripheral surface of a metal tube body is characterized in that the metal tube is formed by using a buffing device having a structure according to any one of the first to eighth aspects. While rotating the body around the central axis, the grinding wheel is rotated around the rotation center axis, and the outer peripheral surface of the grinding wheel is brought into contact with the outer peripheral surface of the metal tube body. By relatively moving the grinding wheel in the direction of the central axis of the metal tube, after rough finishing the outer peripheral surface of the metal tube, the buff wheel is rotated around its rotation center axis,
The metal tube and the buff wheel are relatively moved in the direction of the central axis of the metal tube while the outer surface of the buff wheel is brought into contact with the outer surface of the metal tube rotated around the central axis. By the way, when final finishing the outer peripheral surface of the metal tube body, the rotation center axis of the grinding wheel, the rotation center axis of the buff wheel,
In any case, the angle is set to be different from the central axis of the metal tube body and to be inclined at a certain angle to mutually opposite sides with respect to a tube axis orthogonal plane orthogonal to the center axis direction of the metal tube body. , Features.

According to the method of the first aspect according to the present invention, as can be understood from the description of the present invention relating to the buffing device, the polishing marks on the outer peripheral surface of the metal tube body are removed. It is possible to finish the outer peripheral surface of the metal tube with excellent smoothness and gloss while suppressing it to a level that is difficult for human eyes to recognize. In particular, the present invention makes it possible, for the first time, to automate the finishing of a motorcycle muffler, which has not been realized in the past. Can be greatly contributed to the improvement of the working environment for human beings.

In particular, according to the method of the present invention, a stainless steel motorcycle muffler or the like manufactured from a rolled steel plate or an extruded steel pipe is subjected to rough finishing using a grinding wheel and final finishing using a buff wheel from an untreated state. You can finish up to. In addition, for general stainless steel motorcycle mufflers, etc., by appropriately adjusting the material of the grinding wheel and the buff wheel, the contact pressure against the metal tube, and the number of revolutions thereof, the grinding wheel is used. By performing machining and buffing with a buffing wheel only once in the axial direction on the metal tube, it is possible to finish the product surface with the required accuracy, and at most the metal tube It is possible to perform the final finishing only by performing polishing and buffing several times in the axial direction.

In this embodiment, when a hard metal tube made of stainless steel or the like is processed using a grinding wheel and a buff wheel made of a conventionally used material, the rotation speed of the metal tube is set to 800 ± 500. It is desirable to set the rotation speed of the polishing wheel and the buff wheel to 2200 ± 800 rotations / minute while setting the rotation speed to the rotation speed / minute. By adopting such a rotational speed, the efficiency and accuracy of processing by a grinding wheel or a buff wheel can be further improved. If the rotation speed of the metal tube is lower than 300 rotations / minute, heat damage such as burning or discoloration may occur on the metal tube, and
If the rotation speed is higher than 300 rotations / minute, there is a problem that the load on the drive system is increased and it is difficult to maintain accuracy. In addition, the rotation speed of the grinding wheel or buff wheel is 1400 rotations /
If it is smaller than 3,000 minutes, polishing marks that are easily visible on the outer peripheral surface of the tubular body tend to be easily generated, and 3000 rotations /
If it is larger than the minute, heat damage such as burning and discoloration may occur on the metal tube. More preferably, in a general case where a metal tube made of stainless steel having an outer diameter of 50 to 300 mm is finally finished with a cloth buff wheel having an outer diameter of 100 to 500 mm, a metal tube is used. The rotation speed of the body is set to 800 ± 300 rotations / minute,
The rotation speed of the buff wheel is set to 2200 ± 500 rotations / minute. In this case, the relative displacement speed in the axial direction between the metal tube and the buff wheel is desirably set to about 300 to 3000 mm / min. By adopting such a rotation speed and a feed speed, it is possible to obtain a more excellent buffing surface.

A second aspect of the present invention relating to a method for buffing the outer peripheral surface of a metal tube is a method for buffing according to the first aspect, wherein a grinding wheel or a buff wheel is moved axially with respect to the metal tube. By reciprocating multiple times and moving relatively,
When performing at least one of rough finishing and final finishing multiple times in the axial direction of the metal tube, the inclination angle of the rotation center axis of the grinding wheel or buffing wheel with respect to the center axis of the metal tube is changed and set each time. , Features. According to this aspect, it is possible to more advantageously reduce or prevent the trace of polishing on the outer peripheral surface of the metal tube body generated by the polishing process using the polishing wheel or the buff wheel.

In the case where the change of the inclination angle of the rotation center axis of the grinding wheel or the buff wheel is automatically performed by using an electric motor or the like, the rough finishing and the rough finishing performed a plurality of times are performed. // At the time of final finishing, the inclination angle of the rotation center axis of the grinding wheel or buffing wheel set each time is stored in advance in the control mechanism of the apparatus, and by sequence control,
It is desirable to automatically set the inclination angle of the rotation center axis of the grinding wheel or the buff wheel to a different value each time.

[0040]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, in order to clarify the present invention more specifically, embodiments of the present invention will be described in detail with reference to the drawings.

First, FIG. 1 shows a plan view of a buff finishing device 10 as one embodiment of the present invention,
FIG. 2 shows a front view thereof. FIG. 3 is an explanatory view of a main part of a longitudinal section in FIG. 1, and FIG. 4 is an explanatory view of a main part on a left side surface in FIG. The buffing device 10 includes a bed 12 which is a large, substantially rectangular block-shaped structure. On the bed 12, a metal tube 14 as a workpiece is formed.
Are supported rotatably about a central axis extending in the horizontal direction, while the grinding wheel 16 and the buff wheel 18 are rotatably supported about a rotation central axis extending in the vertical direction. Then, while the metal tube 14 is driven to rotate around the central axis, the grinding wheel 16 and the buff wheel 18 are driven to rotate around the rotation center axis so that the grinding wheel 16 and the buff wheel 18 are sequentially brought into contact with the outer peripheral surface of the metal tube 14 one by one. By moving the metal tube 14 in the axial direction, rough finishing and final finishing of the metal tube 14 are performed.

More specifically, one end of the long side on the bed 12 (the front side of the device located at the lower side in FIG. 1) is located in the direction of the long side (the left-right direction in FIG. 1). Two linearly extending first guide rails 20, 20 are laid, and the first guide rails 20, 20 support a work support base 22 in the shape of a long rectangular flat plate. Reference numerals 20 and 20 are provided so as to be movable. Further, a first ball screw shaft 24 is disposed between the first guide rails 20 and 20 at one end in the longitudinal direction (left end in FIG. 1) so as to be immovable in the axial direction. Being
A first ball screw nut 28, which is rotatable by a manual handle 26 and is screwed to the first ball screw shaft 24, is fixed to the lower surface of the work support 22. Thus, the work support table 22 can be reciprocated in the long side direction of the bed 12 by rotating the manual handle 26. The work support 22 is provided with a positioning plate 30 which is located on the side of the manual handle 26 and extends outward in the moving direction.
By screwing the fixing bolts 34 inserted through the fixing bolts 34 to the fixing plates 36 fixed to the bed 12 and tightening them, the position of the work support base 22 on the bed 12 can be fixedly positioned. It has become.

On the work support table 22, a right support shaft 38 and a left support shaft 40 are disposed on the same central axis so as to face each other on both sides in the longitudinal direction. The right support shaft 38 is rotatably supported around a central axis by a right support base 42 fixed on the work support base 22, and one end in the axial direction (right end in FIG. 2) of the transmission. The output shaft 44 is connected to an output shaft 44, and is rotated by a work rotating motor 46 via a transmission belt 47 and a transmission 44. A right attachment 50 having a receiving surface shape corresponding to the right end surface of the metal tube 14 as a workpiece is bolted to the other end of the right support shaft 38 in the axial direction. The work rotating motor 46 and the transmission 44 are fixed on the work support 22 by a gantry 48.

On the other hand, the left support shaft 40 is rotatably supported around a central axis by a left support table 53 fixed to a moving table 52 mounted on the work support table 22. Here, the moving table 52 is placed on a guide rail 54 laid in the longitudinal direction of the work supporting table 22, is supported movably along the guide rail 54, and is fixed on the work supporting table 22. When the piston rod 58 of the provided drive cylinder mechanism 56 is fixed to the moving table 52, the moving table 52 is reciprocated in the longitudinal direction of the work support table 22 by the driving cylinder mechanism 56. And, the moving table 52 is the work supporting table 2
2, the left support shaft 40 supported by the moving table 52 is reciprocated on the same central axis as the right support shaft 38 in the approaching / separating direction with respect to the right supporting shaft 38. It is like that. Further, a left attachment 60 having a receiving surface shape corresponding to the left end surface of the metal tube 14 is fixed to the right end side in the axial direction of the left support shaft 40 by bolts.

Thus, the movable table 52 is moved to the work support table 2.
2, the metal tube 14 is disposed between the opposing surfaces of the left and right support shafts 40 and 38 in a state where the left support shaft 40 is separated from the right support shaft 38 by moving the metal tube 14 to the left. By driving the left support shaft 40 closer to the right support shaft 38 side by the drive cylinder 56, the metal tube 14 is axially sandwiched between the left and right support shafts 40, 38 and held at both ends in the axial direction. ing. Further, in such a holding state, the metal tube 14 is rotatably supported around a center axis that is aligned with the center axis of the left and right support shafts 40 and 38, and the work rotating motor 46 rotates the metal tube 14. Are driven to rotate about a central axis. In addition, the metal tube body 14 rotatably supported in this way is operated by operating the manual handle 26 to drive the work support base 22 so that the metal tube body 14 and the drive system such as the work rotation motor 46 can be moved in the longitudinal direction of the bed 12. It is said that the position can be adjusted.

On the other hand, the first guide rails 20, 20 for guiding the work support table 22 are provided on the other long side portion (rear side portion located at the upper portion in FIG. 1) on the bed 12. A pair of second guide rails 62, 62 extending in parallel are laid, and a base plate 64 as a base member having a large rectangular flat plate shape is supported by the second guide rails 62, 62. The guide rails 62 are movably disposed on the guide rails 62. Further, between the second guide rails 62, a second ball screw shaft 66 extends in the axial direction from one end (the right end in FIG. 1) in the longitudinal direction to the other end. A second ball screw nut 68 that is arranged immovably and screwed to the second ball screw shaft 66 is fixed to the lower surface of the base plate 64. Then, the base plate 64 is supported on the bed 12 in the long side direction, in other words, by rotating the second ball screw shaft 66 by an axial feed motor 70 attached to one end in the axial direction. The metal tube 14 can be reciprocated in the direction of the central axis of the metal tube 14.

A pair of base plates 64 are located on both sides in the moving direction (left and right sides in FIG. 1) and extend linearly in directions perpendicular to the moving direction (vertical directions in FIG. 1). A third guide rail 72, 72 and a pair of fourth guide rails 74, 74 are laid.
Then, the buff car support base 76 is supported by the third guide rails 72, 72, and the third guide rails 72, 7 are supported.
The polishing wheel support base 78 is supported by the fourth guide rails 74 and 74, and is movably disposed on the fourth guide rails 74 and 74. . In short, the buff wheel support 76 and the grinding wheel support 78 are both supported by the base plate 64 and can be moved integrally in the longitudinal direction of the bed 12 (the left-right direction in FIG. 1). In the width direction of 12 (the vertical direction in FIG. 1), they can move independently of each other on the base plate 64.

A column 79 extending vertically upward is fixed to the buff wheel support base 76. The column 79 fixedly supports the buff wheel bearing body 80 and the buff wheel drive motor 81. I have. The buffing wheel bearing body 80 includes a rotating shaft 82 that is supported rotatably around the central axis and extends in the vertical direction. The buffing wheel 18 is fixed to the lower end of the rotating shaft 82 by bolts or the like. The buff wheel 18 is rotatably supported around a rotation center axis Xb extending in the vertical direction. Then, the rotating shaft 82 of the buff wheel bearing 80 is driven by the
, The buff wheel 18 is driven to rotate. In addition,
The outer peripheral surface 84 of the buff wheel 18 has a substantially rotating cylindrical shape around a rotation center axis: Xb.

On the other hand, the grinding wheel support 78 has substantially the same structure as the buff wheel support 76.
And a column 86 extending vertically upward from the column and fixed thereto.
And a grinding wheel drive motor 90 are fixedly supported. The grinding wheel bearing body 88 includes a rotating shaft 92 that is rotatably supported around a central axis and extends in the vertical direction. The grinding wheel 16 is fixed to a lower end portion of the rotating shaft 92 by bolts or the like. A rotation center axis extending vertically through the grinding wheel 16: X
It is designed to be rotatable about a. Then, the rotating shaft 92 of the grinding wheel bearing body 88 is rotationally driven by the grinding wheel drive motor 90 via the transmission belt 96, so that the grinding wheel 16 is rotationally driven. The outer peripheral surface 94 of the grinding wheel 16
Has a substantially rotating cylindrical shape around a rotation center axis: Xa.

In this embodiment, the center of the buff wheel 18 and the grinding wheel 16 in the axial direction is set so as to be located in a horizontal plane including the central axis of the metal tube 14. The buffing wheel 18 and the grinding wheel 16 are both on the front side of the buffing wheel support 76 or the grinding wheel support 78 (the lower side in FIG. 1).
, And is arranged to face the side surface of the metal tube 14 in the direction perpendicular to the axis. Further, since the buff wheel support 76 and the grinding wheel support 78 are moved independently of each other, the buff wheel 18 and the grinding wheel 16 can move independently of each other in the approaching / separating direction with respect to the metal tube 14. It has been.

By moving the buff wheel support base 76 forward while rotating the buff wheel 18, the outer peripheral surface of the buff wheel 18 is brought into contact with the outer peripheral surface of the metal tube 14, and The body 14 can be polished with a buffing wheel, and the outer peripheral surface of the polishing wheel 16 is moved by moving the polishing wheel support 78 forward while rotating the polishing wheel 16. By contacting the outer peripheral surface of the metal tube 14, the metal tube 14 can be polished by a polishing wheel. In addition, while rotating the metal tube 14 to which the buffing wheel 18 or the grinding wheel 16 is brought into contact with the metal tube body 14 around the central axis, the buffing wheel 18 or the grinding wheel 16 is brought into contact with the metal tube body 14 under the condition. By moving the base plate 64 in one direction, the contact position of the buffing wheel 18 or the grinding wheel 16 with the metal tube 14 can be moved in the axial direction, and the entire outer peripheral surface of the metal tube 14 can be polished. Thus, the outer peripheral surface of the metal tube body 14 can be rough-finished by the grinding wheel 16 and finally finished by the buff wheel 18.

The rotation center axis of the grinding wheel 16 is as follows:
The grinding wheel bearing body 88 that rotatably supports Xa is supported by the support 8.
6, a predetermined angle is set about the tilting center axis Ya extending in the horizontal direction in parallel with the fourth guide rails 74, 74 at right angles to the rotation center axis Xa and across both sides of the vertical line. Only swingable. Then, as shown by an imaginary line in FIG. 3, the grinding wheel bearing body 88 is tilted from the vertical direction by an angle α around the tilting central axis: Ya, thereby polishing the grinding wheel attached to the rotating shaft 92. The rotation direction of the outer peripheral surface 94 of the wheel 16 is set so as to be inclined by an angle α with respect to the horizontal direction, that is, the direction of the central axis of the metal tube 14. Is inclined with respect to the central axis of the metal tube 14. In particular, in the present embodiment, the grinding wheel bearing body 88 can be tiltably set with respect to the support column 86 in the range of α ≦ 20 degrees on both sides of the vertical line around the tilt center axis: Ya. I have. Further, the grinding wheel bearing body 88 is releasably fixed to the column 86 by a plurality of fixing bolts 97 in a state where an arbitrary tilt angle is set. Although not explicitly shown in the drawings, the grinding wheel bearing 88
In addition, the insertion hole of the fixing bolt 97 in the support column 86 is formed in an arc shape extending around the tilt center axis: Ya, so that the grinding wheel bearing body 88 can tilt with respect to the support column 86 around the tilt center axis: Ya. It is now acceptable.

Further, the support system of the buffing wheel 18 is configured similarly to the above-mentioned supporting system of the grinding wheel 16. That is, the buff wheel bearing body 80 that rotatably supports the rotation center axis: Xb of the buff wheel 18 is rotated with respect to the support 79 by the rotation center axis: Xb.
Are mounted so as to be swingable by a predetermined angle around a vertical center line Yb extending in the horizontal direction in parallel with the third guide rails 72, 72 and across the vertical line. Then, as shown by the imaginary line in FIG.
By tilting the buff wheel bearing body 80 about the tilting central axis: Yb from the vertical direction by the angle: β, the rotating shaft 82 is rotated.
The rotation direction of the outer peripheral surface 84 of the buff wheel 18 attached to the metal pipe 14 is set to be inclined by an angle β with respect to the horizontal direction, that is, the center axis direction of the metal pipe 14. The polishing direction of the buffing wheel 18 at 14 is inclined with respect to the central axis of the metal tube 14. In particular, in the present embodiment, the buff wheel bearing body 80 can be tilted with respect to the support column 79 in the range of β ≦ 20 degrees on both sides of the vertical line around the tilt center axis: Yb. I have. Also, the buff wheel bearing body 80
Is releasably fixed to the column 79 with a plurality of fixing bolts 99 set at an arbitrary tilt angle. Although not explicitly shown in the drawing, the insertion hole of the fixing bolt 99 in the buff wheel bearing body 80 or the support 79 has an arc shape extending around the tilting central axis: Yb, so that the buff wheel axle is formed. The tilt of the receiving body 80 with respect to the support 79 around the tilt center axis: Yb is allowed.

On the other hand, the drive of the buff wheel support 76 and the grinding wheel support 78 in the direction of approaching / separating from the metal tube body 14 is performed by the buff wheel abutment devices 98 mounted on both sides in the moving direction of the base plate 64 and the grinding wheel. The contact is performed separately by the contact device 100.

Each of these contact devices 98 and 100 has a pair of fixed plates 1 erected on the base plate 64.
02, 104, and their fixed plates 102, 1
Two guide rods 106, 106 are arranged to extend in the moving direction of the buff wheel support 76 and the grinding wheel support 78 between the 04. A movable plate 108 is provided between the opposing surfaces of the fixed plates 102 and 104, and the movable plates 108 are guided by the guide rods 106 and 106 when the guide rods 106 and 106 are inserted through the movable plate 108. Thus, it is movable on the base plate 64 in the moving direction of the buffing wheel support 76 and the grinding wheel support 78.

In each of the contact devices 98 and 100, the third ball screw shaft 110 is mounted on the base plate 64.
Are disposed in parallel with the guide rod 106 and supported so as not to move in the axial direction.
A third ball screw nut 112 screwed to 10 is fixed to the movable plate 108. When the third ball screw shaft 110 is driven to rotate by the contact motor 114, the movable plate 108 reciprocates on the base plate 64 in the moving direction of the buff wheel support 76 and the grinding wheel support 78. I am being squeezed.

On the other hand, a transmission plate 116 projecting laterally from the columns 79 and 86 is fixed to the buff wheel support 76 and the grinding wheel support 78, respectively.
16 is in front of the movable plate 108 (on the side where the metal tube 14 is provided).
And are opposed to each other. And this transmission plate 1
A holding rod 118 projecting forward from the movable plate 108 is loosely inserted into the movable plate 16. A coil spring 120 as an abutting elastic member is externally inserted into the holding rod 118 so that the movable plate 108 and the transmission plate 116
While the distal end of the holding rod 118 projects through the transmission plate 116,
A retaining nut 122 is screwed and fixed to the protruding tip portion, and the retaining rod 118 is retained so as not to be able to come out of the transmission plate 116.

As a result, the coil spring 120
A coil spring 120 is provided and held between the movable plate 108 and the transmission plate 116 while being compressed by a predetermined amount.
The movable plate 108 and the transmission plate 116 are always connected in a state of being urged in the separation direction by the urging force of the transmission plate, and the relative displacement amount of the transmission plate 116 in the separation direction from the movable plate 108 is 116, the relative displacement of the transmission plate 116 in the direction in which the transmission plate 116 approaches the movable plate 108 is restricted by the coil spring 120.
Is allowed on the basis of the compression deformation.

In the contact devices 98 and 100 having such a structure, the third ball screw shaft 110 is driven to rotate by the contact motor 114 so that the screw feeding action of the third ball screw nut 112 is performed. By displacing the movable plate 108 forward, the displacement force is transmitted to the transmission plate 116 via the coil spring 120, so that the buff wheel support 76 and the grinding wheel support 78 are driven forward. It has become. In addition, as a result of the buff wheel support 76 and the grinding wheel support 78 being driven forward, the buff wheel 18 and the grinding wheel 16 are brought into contact with the outer peripheral surface of the metal tube 14 supported on the work support 22. That is, the outer peripheral surfaces 94 and 84 of the buffing wheel 18 and the grinding wheel 16 are pressed against the outer peripheral surface of the metal tube body 14 with a contact pressure having a magnitude corresponding to the compression spring force of the coil spring 120. It is like that.

In this embodiment, in particular, in the transmission plate 116
Are attached to the columns 79, 86 of the buff wheel support 76 and the grinding wheel support 78, so that the transmission position of the driving force to the buff wheel support 76 and the grinding wheel support 78 is changed to the buff wheel 18 and the grinding wheel 16 metal tubes 14
Is set at substantially the same height as the contact position with respect to. The movable plate 10 is located between the fixed plate 102 and the movable plate 108.
A limit switch mechanism 124 for detecting the movement position of the rear wheel 8 at the backward movement end and the forward movement end is mounted, and the buff wheel support base 76 and the grinding wheel support base on the base plate 64 by the limit switch mechanism 124. The movement range of 78 is restricted.

Further, in this embodiment, the contact pressure of the buffing wheel 18 and the grinding wheel 16 against the metal tube 14 is exerted based on the urging force exerted by the coil spring 120. By adjusting the amount of compressive deformation of the coil spring 120, the contact pressure is controlled so as to have a substantially constant target value.

That is, a distance sensor 126 such as a potentiometer is mounted on the transmission plate 116, and the protruding distal end of the measuring element 128 of the distance sensor 126 is fastened to the distal end of the holding rod 118 by the retaining nut 122. It is in contact with the fixed measuring plate 130. And
With the illustrated relative position of the movable plate 108 and the transmission plate 116 defined by the contact of the transmission plate 116 with the retaining nut 122 as an initial position, the movable plate 108 is moved forward (right side in FIG. 5) from the initial position. By being driven, when the movable plate 108 is displaced relatively close to the transmission plate 116 with the compression deformation of the coil spring 120, the holding rod 118 is projected forward from the transmission plate 116. The measuring plate 130 fixed to the distal end of the holding rod 118 is separated forward from the transmission plate 116 by the distance, so that the tracing stylus 128 of the distance sensor 126
It is extended by a movement amount of zero. As a result, the distance that the transmission plate 116 moves relative to the movable plate 108, and thus the amount of compressive deformation of the coil spring 120, is measured by the distance sensor 126.

Then, a contact pressure controller (not shown) controls the amount of compressive deformation of the coil spring 120 measured by the distance sensor 126 so as to be maintained within a predetermined range, for example, a range of 10 to 30 mm. By controlling the position of the movable plate 108 by controlling the contact motor 114, the compressive force exerted on the coil spring 120 and, consequently, the contact pressure of the buffing wheel 18 and the grinding wheel 16 against the metal tube body 14 are adjusted. It has become so.

Here, such a coil spring 1
Specifically, the control of the amount of compressive deformation of the coil spring 12 is performed by, for example, the coil spring 12 detected by the distance sensor 126.
The compression deformation amount of 0 is monitored by the control device 134, and when the compression deformation amount is within the range of 10 to 30 mm, which is the allowable compression deformation amount input from the set value input device 132, the movable plate 108 is 10-30 without displacement
mm, the contact motor 114 is driven by a drive signal output from the control device 134 so as to be displaced rearward or forward by a predetermined constant distance, for example, 15 mm which is half of the allowable amount of compressive deformation. This can be advantageously performed by, for example, moving the movable plate 108 by rotating it.

As is clear from the above description, in the present embodiment, the tube support means is constituted by including the left and right support shafts 40 and 38 installed on the work support table 22, and Tube rotation drive means includes the rotation motor 46 and the transmission 44. Also, the buff car support 7 movably installed on the base plate 64.
A buffing wheel support means is configured to include the buffing wheel bearing member 80 and a buffing wheel rotation driving means is configured to include a buffing wheel drive motor 81 supported by a buffing wheel support base 76. Furthermore, a buff wheel contact pressure adjusting means is configured to include a buff wheel contact device 98 for driving the buff wheel support base 76 on the base plate 64, and the base plate 64 and the base plate 64 are moved on the bed 12. The buffing vehicle feed means includes the axial feed motor 70 to be executed. Further, the grinding wheel support 78 and the grinding wheel bearing 8 movably installed on the base plate 64.
The polishing wheel support means is configured to include the grinding wheel 8, and the grinding wheel rotation driving means is configured to include the grinding wheel drive motor 90 supported by the polishing wheel support base 78. In addition, a grinding wheel contact pressure adjusting means is configured to include a grinding wheel contact device 100 for driving the grinding wheel support base 78 on the base plate 64, and the base plate 64 and the base plate 64 are moved on the bed 12. The polishing wheel feed means includes the axial feed motor 70.
Further, a tilt angle setting mechanism for positioning and supporting the polishing wheel bearing body 88 so as to be tiltable about the tilt center axis: Ya with respect to the support column 86, and the buff wheel bearing body 80 with respect to the support column 79. A rotation center axis: Xa of the grinding wheel 16 and a rotation center axis: Xb of the buffing wheel 18; and a metal pipe. Angle adjusting means are provided which can be inclined to opposite sides with respect to a vertical plane perpendicular to the center axis of the body 14.

Next, the operation of polishing and polishing the outer peripheral surface of the metal tube 14 using the buffing device 10 having the above-described structure will be described. The metal tube 14 is, for example, a muffler for a motorcycle, and the like.
Those with a built-in silencer can also be targeted.

At the time of such polishing, a set value input device 132 constituting an operation control device of the buff finishing device 10 is used.
The contact pressure of the grinding wheel 16 and the buff wheel 18 against the metal tube 14 or the coil spring 12 corresponding to the contact pressure
Inputting the allowable range of the compression amount of 0, the contact force control device 13
4 is set as the target value.

Also, the tilting angle α of the grinding wheel bearing body 88 with respect to the column 86 and the tilting angle β of the buff wheel bearing body 80 with respect to the column 79 are adjusted and fixedly set, respectively. The rotation center axis Xa of 16 and the rotation center axis Xb of the buff wheel 18 are set to be inclined at different angles with respect to the center axis of the metal tube 14. Here, preferably, as indicated by phantom lines in FIG.
On the opposite sides of a vertical plane perpendicular to the central axis of the metal tube 14, the tilting direction of the rotation center axis of the grinding wheel 16: Xa 'and the rotation center axis of the buffing wheel 18: Xb' are set. I do.

Further, the metal tube 14 is connected to the left and right support shafts 4.
The metal tube 14 is supported on the work support 22 by operating the drive cylinder 56 between the positions 0 and 38, and the work support 22 is moved by operating the manual handle 26, thereby enabling the metal support 14 to move. The tube body 14 is positioned at an appropriate place such as substantially at the center on the bed 12 in consideration of its length and the like. Further, the axial feed motor 70 is operated to move the base plate 64 to the starting end side (for example, FIG.
At the left end of the bed 12 in the longitudinal direction). Further, in the buffing wheel abutting device 98 and the grinding wheel abutting device 100, by operating the abutment motor 114, the buffing wheel support 76 and the grinding wheel support 78 on the base plate 64 are moved to the retracted positions ( Buff car 18
And the polishing wheel 16 is located at a position most distant from the metal tube body 14).

Then, the work rotating motor 46 is operated to rotate the metal tube 14 around the central axis, while the grinding wheel driving motor 90 is operated to rotate the grinding wheel 16 around the rotation central axis: Xa '. . Subsequently, in the grinding wheel contact device 100, the contact motor 114 is operated to bring the outer peripheral surface 94 of the polishing wheel 16 into contact with the outer peripheral surface of the metal tube body 14, and the contact pressure is reduced by polishing. Car abutment device 1
00 and the contact force control device 134 are adjusted to have a preset value. Then, the base plate 64 is moved to the metal tube 14 by operating the axial feed motor 70.
, The contact position of the grinding wheel 16 is displaced from one axial end of the metal tube body 14 to the other end.

As a result, the outer peripheral surface of the metal tube 14 is gradually polished from one end to the other end in the axial direction, and is stroked only once in the axial direction.
Can be rough-finished over the entire surface. It is to be noted that various types of polishing wheels 16 can be employed depending on the material of the metal tube body 14 and the required rough finishing accuracy, for example, in addition to a cloth buff, an abrasive material and a base material. A polishing disk or the like obtained by firing the material can be appropriately adopted,
Specifically, in the case of rough finishing of the metal tube 14 made of stainless steel, for example, one using abrasive grains of about $ 1000 to $ 3000, more preferably about $ 2000 to $ 2500 is suitably used.

Further, after the completion of the rough finishing, the metal tube 14 is finally finished. To do that,
First, the base plate 64, the grinding wheel support 78 and the buff wheel support 76 are returned to the initial positions as described above, and the grinding wheel drive motor 90 is stopped.
1 is operated to rotate the buff wheel 18 around the rotation center axis: Xb '. Subsequently, in the buff wheel abutment device 98, the abutment motor 114 is operated to bring the outer peripheral surface 84 of the buff wheel 18 into contact with the outer peripheral surface of the metal tube 14, and
The contact pressure is adjusted by a contact device 98 for a buffing vehicle so as to have a preset value. Then, by operating the axial feed motor 70 to move the base plate 64 in the axial direction of the metal tube 14, the contact position of the buffing wheel 18 is displaced from one axial end of the metal tube 14 to the other end. Let it.

As a result, the outer peripheral surface of the roughly finished metal tube 14 is gradually buff-polished from one end to the other end in the axial direction, and is stroked only once in the axial direction. The final finish can be made over the entire surface. Depending on the material of the metal tube 14 and the required final finishing precision, various materials can be used as the material of the buffing wheel 18. For example, it is manufactured by sewing cotton or the like. Are preferably employed.

At the time of the rough finishing by the grinding wheel 16 and the final finishing by the buff wheel 18 as described above, an appropriate abrasive may be appropriately used. Specifically, for example, a liquid abrasive is impregnated into the buffing wheel 18 or the polishing wheel 16 or supplied to the polishing portion from the outside, and a solid abrasive is supplied to the buffing wheel 18 or the polishing wheel 16 or the metal tube 14. It is employed by applying it to the surface of

The rotation speed and feed speed of the metal tube 14, the grinding wheel 16 and the buff wheel 18 depend on the required accuracy and the like in addition to the material of the metal tube 14, the grinding wheel 16 and the buff wheel 18. Although not particularly limited, for example, a metal tube 14 of 100 to 200 mmφ made of stainless steel used as a muffler for motorcycles has an outer diameter of 200 to 400 mm. TA2
In the general case of final finishing with a grinding wheel 16 of 2,000 to 2500 or a buffing wheel 18 made of cotton, the rotation speed of the metal tube is set to 800 ± 200 rpm, and
Is preferably set to 2000 ± 250 rotations / minute, and the rotation speed of the buff wheel 18 is set to 2200 ± 250 rotations / minute. Further, the relative feed speed in the axial direction of the grinding wheel 16 and the buff wheel 18 with respect to the metal tube body 14 due to the movement of the base plate 64 is, for example, 500 to 2000 mm /.
It is desirable to set it to about a minute. By setting such rotation speed and feed rate, it is possible to advantageously prevent discoloration and the like caused by burning of the metal tube 14 and to realize excellent processing efficiency (processing cycle). is there.

In the buffing device 10 having the above-described structure, the polishing direction of the grinding wheel 16 with respect to the metal tube 14 at the time of rough finishing and the metal tube of the buffing wheel 18 at the time of final finishing are described. The polishing direction can be set to an arbitrary direction different from each other, whereby an extremely excellent surface property can be advantageously realized so that polishing marks or the like can hardly be visually confirmed.

In particular, in this embodiment, the rotation center axis of the grinding wheel 16: Xa 'and the rotation center axis of the buff wheel 18: Xb'
By setting the inclination on the opposite side with respect to the tube axis orthogonal plane perpendicular to the central axis of the metal tube 14, a more accurate tube surface state can be obtained. In short, polishing wheel 1
6 and Xa 'and the rotation axis of the buff wheel 18: X
b ′ is inclined to the opposite side with respect to a tube axis orthogonal plane orthogonal to the central axis of the metal tube 14, so that the metal tube 14
Grinding wheel 16 and buffing wheel 18 in the rotation direction (circumferential direction) of
While maintaining the inclination angle in the polishing direction (rotation direction) as large as possible, that is, at a relative inclination angle close to 90 degrees, the rotation center axes of the grinding wheels 16 and the buff wheels 18: Xa ′, X
The relative angle difference of b 'can be set to be large, so that the polishing scratches at the time of rough finishing by the grinding wheel 16 and the polishing scratches at the final finishing by the buffing wheel 18 are offsetly reduced. Thus, the effect of improving the finishing accuracy by this and the effect of improving the finishing accuracy by preventing the polishing scratches in the circumferential direction of the pipe by the grinding wheel 16 and the buff wheel 18 can be synergistically exhibited.

Further, the buff finishing device 1 having the above-described structure is used.
At 0, the grinding wheel 16 and the buff wheel 18 are supported by the same base plate 64 and are displaced integrally with respect to the metal tube body 14.
Not only the device structure is simple, but also the operation mechanism can be simplified and the operation accuracy can be improved.

Further, at the time of polishing, the metal tube 14
Is held at both ends in the axial direction, so that the center axis is prevented from shaking and stable polishing is realized, and since there is no need to support the outer peripheral surface with a roller, etc. The generation of scratches on the outer peripheral surface of the metal tube 14 due to the above is advantageously prevented, and more excellent processing accuracy can be realized.

Further, since the metal tube 14 is supported at both ends in the axial direction, the metal tube 14 can be rotated at a high speed around the center axis while avoiding the deviation of the center axis. In addition to improving the polishing efficiency (working cycle), it is possible to advantageously achieve the prevention of burn defects during polishing of the metal tube 14.

Further, in the present embodiment, the contact device 9 for adjusting the contact pressure of the buffing wheel 18 and the grinding wheel 16 against the metal tube 14.
8, 100, a coil spring 120 is employed, and the contact pressure of the buffing wheel 18 and the grinding wheel 16 against the metal tube body 14 is controlled by maintaining the compression amount of the coil spring 120 within a predetermined range. Therefore, the contact pressure can be controlled using a distance sensor, which is generally less expensive than a pressure sensor or the like. In addition, by adjusting the elastic coefficient of the coil spring 120 appropriately, there is an advantage that the adjustment accuracy of the contact pressure can be advantageously secured without increasing the detection accuracy of the distance sensor 126 itself. Further, since the urging force of the coil spring 120 is always applied as the contact pressure, a stable contact pressure is maintained as compared with, for example, control of the contact pressure by simply controlling the position of the buffing wheel 18 or the polishing wheel 16. As a result, the polishing accuracy can be more advantageously and stably obtained.

Further, in the buff finishing device 10 of the present embodiment, the work support table 2 for supporting the metal tube 14 is provided.
2, since the position of the metal tube 14 can be adjusted in the axial direction of the metal tube 14 with respect to the bed 12, there is also an advantage that it can advantageously cope with a difference in the axial length of the metal tube 14 and the like. is there.

Although the embodiments of the present invention have been described in detail, these are merely examples, and the present invention is not to be construed as being limited by the specific description in the embodiments.

For example, the tilt angles of the rotation center axes Xa and Xb of the grinding wheel 16 and the buff wheel 18 are not limited by the specific description in the above embodiment. For example, the rotation center axis: Xa of the grinding wheel 16 is set to α ≠ 0 on any one side with respect to a plane orthogonal to the center axis of the metal tube body 14.
And the rotation center axis of the buff wheel 18: Xb
May be set at β = 0 on a plane orthogonal to the central axis of the metal tube 14. By setting β = 0 or β ≒ 0, the direction of buff polishing at the time of final finishing is made closer to the tube axis direction, and therefore, there is an advantage that polishing scratches are more difficult to be visually observed.

Although not shown in the above embodiment, for example, cooling air is supplied to the inside of the metal tube 14 by forming air supply / discharge holes through the left and right support shafts 40 and 38. Alternatively, it is also effective to supply an air discharge port to the base plate 64 and supply cooling air to a polishing portion of the metal tube 14.

Further, the base plate 64 is placed on the bed 1
2 and the work support 22 during polishing.
By moving the metal tube 14 in the longitudinal direction with respect to the bed 12, the metal tube 14 may be moved in the axial direction with respect to the grinding wheel 16 and the buff wheel 18.

In addition, in the above embodiment, the case where the muffler for a motorcycle is polished is described. However, the present invention is also applicable to a metal pipe used for an exterior of an automobile, a building, a ship, or the like. Alternatively, it is needless to say that any of them can be advantageously applied to the final finishing of various metal tubes such as a metal cylinder made of aluminum alloy or the like used in an electrostatic copying machine or a printer.

In addition, although not enumerated one by one, the present invention
Based on the knowledge of those skilled in the art, various changes, modifications, improvements, and the like can be made, and unless such embodiments depart from the spirit of the present invention.
Both are included in the scope of the present invention,
Needless to say.

[0089]

As is apparent from the above description, according to the present invention, the final finishing process on the outer peripheral surface of the metal pipe can be performed with high accuracy and stability.
The rough finishing by the grinding wheel and the final finishing by the buffing wheel are performed in different directions with respect to the metal pipe body and in any direction inclined with respect to the pipe axis direction. It became possible to suppress it to an extent that it would not be.

In particular, according to the present invention, the finish processing of the outer peripheral surface of the metal pipe body, which has conventionally relied exclusively on manual labor, can be automatically performed mechanically.
In addition to the technical significance as described above, the present invention automates buff finishing, which conventionally required work in a bad environment that could harm health, thereby significantly reducing working conditions or working environment. It has great social significance in that it can be improved.

[Brief description of the drawings]

FIG. 1 is a plan view schematically showing a buff finishing device as one embodiment of the present invention.

FIG. 2 is a front view of the buff finishing device shown in FIG.

FIG. 3 is an enlarged partial longitudinal sectional view showing a main part of the buff finishing device shown in FIG. 1;

FIG. 4 is an explanatory diagram showing an enlarged main part of a left side surface in FIG. 2;

FIG. 5 is an enlarged explanatory view of a main part schematically showing one embodiment of the present invention relating to a contact pressure adjusting device employed in the buff finishing device shown in FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Buff finishing device 14 Metal tube 16 Grinding wheel 18 Buff wheel 38 Right support shaft 40 Left support shaft 46 Work rotation motor 64 Base plate 70 Axial feed motor 76 Buff wheel support 78 Polish wheel support 80 Buff wheel bearing 81 Buff Car drive motor 88 Polishing wheel bearing body 90 Polishing wheel drive motor 98 Buffing wheel contact device 100 Polishing wheel contact device 114 Contact motor 126 Distance sensor

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B24B 29/00, 47/20

Claims (8)

(57) [Claims] 1. A tube support means for holding both ends of a metal tube in the axial direction and rotatably supporting the metal tube around a central axis, and a metal tube supported by the tube support means. Tube rotation driving means for rotating the metal tube about a central axis, and a polishing wheel for performing rough finishing on an outer peripheral surface of the metal tube can be rotated and relatively moved in a direction approaching / separating from the metal tube. Grinding wheel support means for supporting the grinding wheel, grinding wheel rotation driving means for rotating the grinding wheel supported by the grinding wheel support means about its rotation center axis, and the outer peripheral surface of the grinding wheel to the metal tube body Grinding wheel contact pressure adjusting means for making contact with the outer peripheral surface at a substantially constant pressure, grinding wheel feeding means for relatively moving the metal tube and the grinding wheel in the direction of the central axis of the metal tube, A buff wheel that performs a final finish on the outer peripheral surface of the metal tube body Buffing wheel support means rotatably supported independently of the polishing wheel so as to be relatively movable in the approaching / separating direction with respect to the metal tube body; and rotating the buffing wheel supported by the buffing wheel supporting means. Buffing wheel rotation driving means for rotating and driving around a central axis; buffing wheel contact pressure adjusting means for bringing the outer peripheral surface of the buffing wheel into contact with the outer peripheral surface of the metal tube at a substantially constant pressure; Buffing wheel feed means for relatively moving the tube and the buff wheel in the direction of the central axis of the metal tube; an inclination angle of a rotation center axis of the polishing wheel with respect to the metal tube; and a rotation center axis of the buffing wheel The inclination angle with respect to the metal tube body can be adjusted and set independently of each other, so that the rotation center axis of the grinding wheel and the rotation center axis of the buff wheel are different from each other and with respect to the center axis of the metal tube body. And set them in different directions. Angle adjusting means to obtain, while rotating the metal tube around a central axis, while rotating the polishing wheel and the buff wheel around the respective rotation center axis, sequentially on the outer peripheral surface of the metal tube While abutting,
The metal tube and the grinding wheel and the buff wheel are relatively moved in the direction of the central axis of the metal tube so that the outer peripheral surface of the metal tube is rough-finished and finally finished. A buff finishing device for an outer peripheral surface of a metal tube body. 2. In the angle adjusting means, the rotation center axis of the grinding wheel and the rotation center axis of the buff wheel are both ± 2 with respect to a tube axis orthogonal plane orthogonal to the center axis of the metal tube.
2. The buffing device according to claim 1, wherein the buffing device is inclined in a range of 0 degrees and is set at mutually different inclination angles. 3. In the angle adjusting means, the rotation center axis of the polishing wheel and the rotation center axis of the buff wheel are located on opposite sides of a pipe axis orthogonal plane orthogonal to the center axis of the metal pipe body. 3. The buffing device according to claim 1, wherein the inclination is set. 4. A base member is provided so as to be relatively movable with respect to the metal tube in the direction of the central axis of the metal tube, and the polishing wheel and the buff wheel are both supported by the base member. And the buffing wheel are integrally moved relative to the metal tube body in the axial direction to form the polishing wheel feeding means and the buffing wheel feeding means, while the polishing wheel and 4. The polishing wheel support means and the buff wheel support means provided with a guide mechanism for relatively moving the buff wheel relative to the metal tube body in the approaching / separating direction, respectively. A buffing device as described. 5. The apparatus according to claim 5, wherein the pipe body rotation driving unit, the grinding wheel rotation driving unit, the grinding wheel feeding unit, the buff wheel rotation driving unit, and the buff wheel feeding unit are controlled to control the rotation. The rotation speed of the metal tube, the rotation speed of the grinding wheel, the relative movement speed of the grinding wheel with respect to the metal tube in the axial direction, the rotation speed of the buff wheel, and the rotation speed of the buff wheel with respect to the metal tube. The buffing device according to any one of claims 1 to 4, further comprising drive control means for presetting the relative movement speed in the axial direction in a pattern. 6. The grinding wheel supporting means includes a grinding wheel pressing member which is driven and displaced in the direction of approach to the metal tube, and the driving force of the grinding wheel pressing member in the direction of approaching the metal tube is polished. Through the elastic member for vehicle contact,
The grinding wheel is brought into contact with the metal tube body by exerting on the grinding wheel, and the grinding wheel is adjusted so that the elastic deformation amount of the grinding wheel contacting elastic member becomes a preset target value. The buffing device according to any one of claims 1 to 5, wherein a position of the pressing member is adjusted. 7. The buff wheel supporting means includes a buff wheel pressing member that is driven and displaced in the direction of approach to the metal tube, and reduces the driving force of the buff wheel pressing member in the direction of approach to the metal tube. Through the elastic member for vehicle contact,
The buff wheel is brought into contact with the metal tube body by exerting the force on the buff wheel, and the buff wheel is brought into contact with the metal member so that the amount of elastic deformation of the buff wheel contacting elastic member becomes a preset target value. 7. The buffing device according to claim 1, wherein the position of the pressing member is adjusted. 8. Using the buffing device according to any one of claims 1 to 7, rotating the metal tube around a central axis, and rotating the polishing wheel around the central axis of rotation. The metal tube and the grinding wheel are relatively moved in the direction of the central axis of the metal tube while the outer surface of the grinding wheel is in contact with the outer surface of the metal tube. After roughening the surface, the buff wheel is rotated around its rotation center axis, while the outer peripheral surface of the buff wheel is brought into contact with the outer peripheral surface of the metal tube body rotated around the central axis,
When the outer peripheral surface of the metal tube is finally finished by relatively moving the metal tube and the buff wheel in the direction of the center axis of the metal tube, the rotation center axis of the grinding wheel and the buff wheel Each of the rotation center axes is in a different direction with respect to the center axis of the metal tube body, and at a predetermined angle on opposite sides of a tube axis orthogonal plane orthogonal to the center axis direction of the metal tube body. A method for buffing the outer peripheral surface of a metal tube, wherein the method comprises setting an inclination.