JP2005169589A - Polishing method of metal ring for endless belt of continuously variable transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polishing method of a metal ring for an endless belt of an continuously variable transmission capable of precisely polishing the side end edge of the metal ring to a desired shape without being influenced by the wear of a polishing brush. <P>SOLUTION: The polishing method has a polishing process polishing the side end edge of the metal ring W by a rotating polishing brush 2. In the polishing process, when the polishing brush 2 abuts on the metal ring W, the load current value of a motor rotate-driving the polishing brush 2 is detected, and the cut depth of the polishing brush 2 to the metal ring W is increased/decreased so that the detected load current value becomes the predetermined load current value. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for polishing a thin cylindrical metal ring used for an endless belt of a continuously variable transmission.

  2. Description of the Related Art In a power transmission belt employed in a continuously variable transmission, a belt in which a plurality of elements arranged in a ring shape are bundled by a laminated ring formed by laminating a plurality of metal rings is used. A metal ring constituting this type of laminated ring is formed in an endless belt shape by cutting a cylindrical metal drum into a ring for each predetermined width. And since the metal ring cut from the cylindrical drum has a very sharp side edge, it is necessary to polish the side edge of the metal ring and finish the side edge into a highly accurate curved shape. Become.

  Conventionally, barrel polishing is used as a method for polishing the side edge of a metal ring (see Patent Document 1). In this kind of barrel polishing, a metal ring is mixed in a barrel filled with a grindstone called a medium, and the barrel is rotated together with the metal ring. As described above, the metal ring is agitated in the barrel together with the medium so that the medium comes into contact with the side edge of the metal ring and the side edge of the metal ring is polished.

  However, in barrel polishing, the metal ring is agitated in the barrel together with the media to bring the media into contact with the side edges of the metal ring, so the degree of polishing tends to be uneven and the processing of the side edges of the metal ring is difficult. There is a disadvantage that the shape cannot be accurately controlled so as to be a desired shape.

  In order to eliminate the disadvantages of barrel polishing, the polishing brush is brought into contact with one side edge of the metal ring while rotating the metal ring in the circumferential direction so that the polishing brush crosses the rotation track of the metal ring. It is conceivable that the side edge of the metal ring is polished. In this case, after polishing one side edge of the metal ring, the other side edge of the metal ring may be similarly polished. By doing so, the amount of cut into the metal ring of the polishing brush (the dimension from the metal ring edge to the polishing brush tip when the polishing brush abuts on the metal ring) is adjusted to adjust the side edge of the metal ring. The shape can be polished to a desired shape.

  However, since this type of polishing brush is generally formed by bundling a nylon wire containing an abrasive, it wears as the metal ring is polished. When the worn polishing brush is used, the cutting amount of the polishing brush into the metal ring is small, and the side edge of the metal ring is not polished into a desired shape.

Therefore, it is known that when the polishing brush reaches a predetermined number of times or a predetermined usage time, the movement amount of the polishing brush toward the polishing position is increased by a certain amount (see Reference 2). However, even if the degree of wear of the polishing brush is predicted from the number of times and the time of use of the polishing brush, if the wear degree of the actual polishing brush is different, the edge of the metal ring may be formed in a desired shape. However, it is difficult to finish the side edge of the metal ring into a highly accurate curved shape.
JP 2001-241512 A Japanese Utility Model Publication No. 7-3950

  The present invention eliminates such inconvenience, and the present invention provides a metal for an endless belt of a continuously variable transmission capable of polishing a side edge of a metal ring to a desired shape with high accuracy without being affected by abrasion of the polishing brush. An object is to provide a method for polishing a ring.

  In order to achieve such an object, the present invention is a method for polishing a thin cylindrical metal ring used for an endless belt of a continuously variable transmission, wherein the metal ring is held in a substantially circular shape and rotated in the circumferential direction. And a polishing step of polishing a side edge of the metal ring by bringing the rotating polishing brush into contact with the rotating track of the metal ring so that the polishing brush is attached to the metal ring. The load current value of the motor that rotationally drives the polishing brush is detected when the contact is made, and the metal ring of the polishing brush is set so that the detected load current value becomes a load current value within a predetermined range set in advance. It is characterized by increasing or decreasing the depth of cut.

  According to the present invention, the edge of the metal ring is polished by the polishing step. That is, first, the metal ring is held in a substantially circular shape and rotated in the circumferential direction. The polishing brush is brought into contact with one side edge of the metal ring while maintaining the rotation state of the metal ring. At this time, the polishing brush is rotated by contacting the polishing brush so as to cross the rotation orbit of the metal ring. Due to the rotation of the metal ring, the rotating polishing brush is in contact with the entire circumference of one side edge of the metal ring for polishing. As described above, according to the polishing by the polishing brush, unlike the conventional barrel polishing, the polishing amount of the side edge of the metal ring can be increased or decreased by the amount of cutting into the metal ring of the polishing brush, and the metal ring It becomes easy to polish the side edge to a desired shape. In the present invention, both side edges of the metal ring can be polished by polishing one side edge of the metal ring and then polishing the other side edge of the metal ring in the same manner.

  In the polishing process of the present invention, the amount of cut into the metal ring of the polishing brush according to the load current value detected from the motor of the polishing brush as a substitute characteristic of the motor rotation shaft torque representing the polishing force for controlling the polishing shape Increase or decrease. That is, when the polishing brush is rotating and abutting against the side edge of the metal ring for polishing, a load is applied to the motor of the polishing brush. The load applied to the motor is detected as a load current value of the motor. At this time, the load current value of the motor becomes large when the cutting amount of the polishing brush into the metal ring is large, and the load current value becomes small when the cutting amount is small. On the other hand, if the cutting amount of the polishing brush into the metal ring is large, the polishing amount of the side edge of the metal ring by the polishing brush is large, and if the cutting amount is small, the polishing amount is small. Accordingly, if the motor load current value is large, it can be confirmed that the polishing amount is large, and if the motor load current value is small, it can be confirmed that the polishing amount is small. Thus, a range of load current values (a predetermined range of load current values) in which a good polishing amount can be obtained can be determined in advance.

  For example, when the polishing brush is worn out, the load current value of the motor decreases. Therefore, even if the polishing brush is worn by increasing the amount of cutting into the metal ring of the polishing brush, the predetermined polishing is ensured. It can be an amount. In this way, by increasing or decreasing the amount of cutting into the metal ring of the polishing brush so that the load current value of the motor is within a predetermined range, the predetermined polishing amount is not affected by the abrasion state of the polishing brush. Can be obtained.

  Furthermore, the present invention, prior to the polishing step, measuring the first current value of the motor when the polishing brush is rotationally driven in a state where the polishing brush and the metal ring are not in contact with each other; A step of measuring the polishing amount when the polishing brush is brought into contact with the metal ring and the edge of the metal ring is polished and a second current value of the motor; a second current value corresponding to the first current value; The step of calculating the correlation between the load current value and the polishing amount using the increase in the current value as the load current value, and the predetermined step in the polishing step based on the correlation between the calculated load current value and the polishing amount And a step of setting a load current value in a range.

  The load current value of the motor can be easily obtained from the increase in the second current value with respect to the first current value. Further, from the correlation between the load current value and the polishing amount, the range of the load current value when a predetermined polishing amount is obtained can be easily obtained. By setting the range of the load current value thus determined prior to the polishing step, the amount of cut into the metal ring of the polishing brush can be accurately increased or decreased in accordance with the load current value in the polishing step. .

  An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an explanatory view showing a metal ring whose both edges are polished in this embodiment, FIG. 2 is an explanatory perspective view schematically showing the brush polishing apparatus of this embodiment, and FIG. 3 is a view of a holding table and a polishing brush. FIG. 4 is an explanatory sectional view showing the polishing means, FIG. 5 is an explanatory view schematically showing the operation of the polishing brush, and FIG. 6 is an illustration showing the polishing state of the metal ring by the polishing brush. 7 is a diagram showing the relationship between the cutting amount of the polishing brush and the load current value of the motor, and FIG. 8 is an explanatory diagram showing the polishing amount according to the cutting amount.

  As shown in FIG. 1, the metal ring W is formed in a thin plate-like endless belt shape, and is used for an endless belt of a continuously variable transmission. Although not shown, the metal ring W is formed into an endless belt shape by cutting a cylindrical metal drum into predetermined circles. The metal ring W immediately after being cut from the cylindrical drum has a very sharp side edge. In the present embodiment, by polishing the side edge of the metal ring W, both edges are processed into a predetermined curved shape as shown in a cross section in the enlarged view of FIG.

  As shown in FIG. 2, a brush polishing apparatus 1 which is an apparatus for realizing the method of the present invention includes a cylindrical brush head 3 having a plurality of polishing brushes 2 provided on the circumference, and six metals. And a table 4 for holding the ring W.

  The table 4 is provided with ring holding means 5 for holding the metal ring W from the inside. The ring holding means 5 is formed by six abutting members 6 as shown in FIG. 3, with the six abutting members 6 being brought close to each other, a metal ring W is placed around the six abutting members 6 The abutting member 6 is separated from the inner peripheral surface so as to abut against the metal ring W and is held in a substantially circular shape. The ring holding means 5 is rotated by a motor (not shown) to rotate each metal ring W in the circumferential direction.

  The brush head 3 is provided in the polishing means 7 as shown in FIG. That is, the polishing means 7 includes an elevating frame 10 that can elevate along a rail 9 provided on a support column 8 standing along the axis of the table 4 (see FIG. 2), and a plurality of bearings 11 on the elevating frame 10. The rotary shaft 12 is rotatably supported via a shaft, the brush head 3 is connected to the lower end thereof, and a motor 14 that rotationally drives the rotary shaft 12 via a belt 13. The elevating frame 10 is raised and lowered toward the table 4 by elevating means (not shown). As the elevating frame 10 is lowered, the polishing brush 2 is lowered to a position where it can abut against one side edge of the metal ring W.

  Further, as schematically shown in FIG. 4, the polishing unit 7 includes a load current value detection unit 15 that detects a load current value of the motor 14, and a current value detected by the load current value detection unit 15. Elevating control means 16 for controlling the elevating means.

  The brush head 3 holds the polishing brush 2 in which a nylon wire containing an abrasive is bundled in a circular shape. As shown in FIG. 5, the polishing brushes 2 arranged in a circular shape have a diameter dimension that simultaneously contacts the metal rings W on the table 4 when rotated. When the brush head 3 shown in FIG. 4 is lowered, as shown in FIG. 5, the polishing brush 2 abuts on one side edge across each metal ring W, and the polishing brush 2 rotates. By the rotation of the metal ring W, the entire circumference of one side edge of the metal ring W is polished. At this time, as shown in FIG. 6, the polishing brush 2 gets over one side edge of the metal ring W, and one side edge of the metal ring W is polished into a predetermined curved shape.

  The brush head 3 shown in FIG. 4 may be controlled by the motor 14 so as to repeat forward rotation and reverse rotation alternately. Specifically, the polishing brush 2 is rotated clockwise to polish the metal ring W for a predetermined time, and then the polishing brush 2 is rotated counterclockwise to perform polishing for a predetermined time. Thus, by rotating the polishing brush 2 clockwise and counterclockwise, the metal ring W can be polished uniformly, and the polishing brush 2 can be prevented from wrinkling.

  When the side edge of the metal ring W is polished by the brush polishing apparatus 1 configured as described above, first, six metal rings W are attached to each ring holding means 5 as shown in FIGS. And is held on the table 4. Next, each ring holding means 5 is rotated, whereby each metal ring W is rotated. Then, the brush head 3 is rotated by driving the motor 14 (see FIG. 4) and the polishing brush 2 is brought into contact with one side edge of the metal ring W. Thereby, as shown in FIG. 6, the side edge of the metal ring W is polished by the polishing brush 2 (polishing step). That is, the polishing means 7 is lowered, and the polishing means 7 is fixed when the polishing brush 2 reaches a predetermined cutting depth with respect to the metal ring W. Thereafter, when the metal ring W is polished, the load current value of the motor 14 changes according to the wear of the polishing brush 2. Since the change in the load current value is detected by the load current value detection means 15, the elevation control means 16 raises and lowers the load current value so that the detected load current value becomes a load current value within a predetermined range set in advance. Then, the brush head 3 is lowered, and the cutting amount is controlled to be constant. In addition, what is shown with the code | symbol 3a in FIG. 4 is the support plate which supports the front-end | tip part of the polishing brush 2, and makes the polishing brush 2 into the polishing brush 2 by making the polishing brush 2 protruded downward from the support plate 3a into a predetermined protrusion amount. Appropriate rigidity and processing force are imparted. When the metal ring W is polished, the brush head 3 is lowered so that the protruding amount of the polishing brush 2 becomes constant according to the wear of the polishing brush 2. Accordingly, the amount of cutting into the metal ring W by the polishing brush 2 is constant.

  Here, the operation of the load current value detection means 15 and the elevation control means 16 will be described in more detail. The load current value detecting means 15 includes a current value (first current value) measured when the polishing brush 2 is not in contact with the metal ring W (during idling), and the polishing brush 2 is connected to the metal ring W. The load current value is detected by calculating the difference from the current value (second current value) measured in the contact state (during polishing).

  On the other hand, the elevation control means 16 stores a range of load current values corresponding to a good polishing amount based on the correlation between the load current value calculated in advance and the polishing amount. The correlation between the load current value and the polishing amount is obtained as follows. That is, when the polishing brush 2 is rotating and contacting the side edge of the metal ring W to perform polishing, a load is applied to the motor 14 of the polishing brush 2. The load applied to the motor 14 is detected by the load current value detecting means 15 as the load current value of the motor 14. At this time, as shown in FIG. 7, the load current value I of the motor 14 is large when the cutting amount L into the metal ring W of the polishing brush 2 is large, and the load current value I is small when the cutting amount L is small. It becomes.

Further, FIG. 8A shows the shape of the side edge of the metal ring (before polishing) immediately after being cut from the cylindrical metal drum. As shown in FIG. When polishing is performed with a small cutting amount L into the metal ring W, the amount of polishing becomes small, and the side edge of the metal ring W is polished into a curved shape with a relatively large tip radius. As shown in FIG. 8C, when polishing is performed with a large cut amount L into the metal ring W of the polishing brush 2, the polishing amount becomes large, and the side edge of the metal ring W has a relatively small tip radius. Polished into a curved shape. From this, it is possible to determine the cutting depth L necessary for polishing into a good curved shape. Then, it is possible to determine the depth of cut L and the load current value from the relationship between I, good depth of cut ranges I ₁ ~I ₂ ranges L ₁ ~L ₂ to become the load current value I L shown in FIG.

The elevation control means 16 monitors whether or not the load current value detected by the load current value detection means 15 is within a predetermined range I _{1 to} I ₂ (range of load current value corresponding to a good polishing amount). When the load current value exceeds the range upper limit I ₂ , the brush head 3 is raised to reduce the cutting amount L, and when the load current value becomes smaller than the range lower limit I ₂ , the brush head 3 is lowered. To increase the cutting depth L.

  Thus, specifically, even when the polishing brush 2 is worn and the cutting depth L is small, the brush head 3 is lowered and the cutting depth L is increased, and a good polishing amount can be maintained. That is, when the polishing brush 2 is worn, the cutting amount L becomes small as shown in FIG. 8B, so that the load current value of the motor 14 of the polishing brush 2 decreases. The load current value at this time is detected by the load current value detection means 15 and sent to the elevation control means 16. Since the raising / lowering control means 16 lowers the brush head 3 in response to a decrease in the load current value, the cutting amount L increases and a good polishing amount can be obtained as shown in FIG.

  In the elevation control means 16, the lower limit position of the brush head 3 is set, and when the cutting amount L is increased according to the load current value detected by the load current value detection means 15, polishing is performed. If the lower limit position of the brush head 3 is exceeded when the brush 2 is extremely worn, etc., the polishing brush 2 can be exchanged smoothly by stopping the polishing process.

Explanatory drawing which shows the metal ring by which the both-ends edge was grind | polished in embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS Explanatory perspective view which shows the brush grinding | polishing apparatus of this embodiment typically. Explanatory drawing which shows typically the action | operation of a holding table and a polishing brush. Explanatory sectional drawing which shows a grinding | polishing means. Explanatory drawing which shows the action | operation of an abrasive brush typically. Explanatory drawing which shows the grinding | polishing state of the metal ring with a grinding | polishing brush The diagram which shows the relationship between the cutting amount of a grinding | polishing brush, and the load current value of a motor. Explanatory drawing which shows the grinding | polishing amount according to the cutting amount.

Explanation of symbols

  W ... Metal ring, 2 ... Polishing brush, 14 ... Motor, I ... Load current value, L ... Cutting depth.

Claims (2)

A method of polishing a thin cylindrical metal ring used for an endless belt of a continuously variable transmission,
A polishing step in which the metal ring is held in a substantially circular shape and rotated in the circumferential direction, and the rotating polishing brush is brought into contact with the metal ring so that one side edge of the metal ring is polished. With
In the polishing step, when the polishing brush contacts the metal ring, a load current value of a motor that rotationally drives the polishing brush is detected, and the detected load current value is within a predetermined range of load current. A method for polishing a metal ring for an endless belt of a continuously variable transmission, wherein the amount of cut into the metal ring of the polishing brush is increased or decreased so as to be a value. Prior to the polishing step,
Measuring the first current value of the motor when the polishing brush is rotationally driven in a state where the polishing brush and the metal ring are not in contact with each other;
Measuring the polishing amount when the polishing brush is in contact with the metal ring and the edge of the metal ring is polished and the second current value of the motor;
Calculating the correlation between the load current value and the polishing amount using the increase in the second current value relative to the first current value as the load current value;
2. The continuously variable transmission according to claim 1, further comprising a step of setting a load current value in a predetermined range in the polishing step based on a correlation between the calculated load current value and a polishing amount. Polishing method of metal ring for endless belt.

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