JP2002263905A - Method and device for grinding brake rotor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for grinding a brake rotor capable of preventing the attitude of a corrected rotor surface from being changed even when a jig is removed. SOLUTION: In this method for grinding the brake rotor, when the rotor surface 8b of the brake rotor 8 is ground with a cutter after the jig 3 is assembled into a part of the brake rotor 8 by utilizing hub bolts 2, washers 15 having the same contact area as the contact areas of the hub nuts 7 with the rotor are inserted between the brake rotor 8 and the jig 3 to install the jig 3 on the brake rotor 8. Thus, the inclination of a hub surface 1a caused by the misalignment of the gravity center of a tightening force by all hub nuts 7 from a wheel hub 1 from an axis can be suppressed during the grinding of the rotor.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for grinding a brake rotor for grinding a side surface of the brake rotor.

[0002]

2. Description of the Related Art Disc brakes are widely used as brakes for automobiles (vehicles). In the disc brake device, a hat-shaped brake rotor is attached to the front of the wheel hub attached to the spindle, a pair of pads are arranged on both sides of the brake rotor, and both pads sandwich the flange-shaped rotor part from both sides This is a device that obtains a braking force.

[0003] By the way, in a vehicle equipped with a disc brake device, a vibration called a brake judder is caused by a brake operation due to a circumferential rotor thickness due to uneven wear of a rotor side surface caused by a runout of a brake rotor. May appear. The brake judder is
This is a phenomenon that occurs when a pad that sandwiches the brake rotor becomes a vibration source and the vibration is transmitted to various parts of the vehicle body such as a steering wheel, a brake pedal, and a floor via a brake pipe and underbody parts.

[0004] In a repair shop or the like, a grinding device for grinding the rotor with the brake rotor attached to the vehicle body is prepared so that the brake judder can be easily dealt with.

[0005] In this grinding apparatus, a jig for rotating the brake rotor by rotation of a rotation transmission mechanism and a rotor surface (side surface) on both sides of the brake rotor are attached to a brake rotor attached to the vehicle body, which is called an on-car race. A grinding method for uniformly grinding the circumferential thickness of the brake rotor in combination with a grinding mechanism for grinding has been used.

Conventionally, this grinding method includes a wheel with a tire as shown in FIG. 5 (neither is shown).
By using a part of a plurality (four in this case) of hub bolts 2 (corresponding to wheel fastening portions) on the front surface (wheel mounting surface) of the central portion of the hat-shaped brake rotor 8 appearing after removing the A method is used in which the tool 3 is fastened to the brake rotor 8 and then the grinding process is started.

The jig 3 has, for example, a small fan-shaped fixed seat 5 having one through hole 5 a (bolt insertion hole) through which the hub bolt 2 can be inserted, and a U-shaped, for example, projecting from the surface of the fixed seat 5. A structure having a member 6a and an engaging portion 6 formed of a rod-shaped member for transmitting a driving force is used (note that the rod-shaped member protrudes from the U-shaped member 6a so as to extend toward the center of the rotor. There). This jig 3 has a through hole 5
a is inserted through one of the hub bolts 2 and arranged on the front surface of the brake rotor 8 (the U-shaped engaging portion 6 is oriented in the circumferential direction), and then protrudes from the fixed seat 5. By screwing a hub nut 7 (corresponding to a fastening member combined with a wheel fastening portion) into the tip of the hub bolt 2,
Assemble to hub wheel 1.

In the rotor grinding, the hub nuts 2 are fastened to the remaining hub bolts 2 with the same specified tightening torque as when the jig 3 is fastened to suppress the distortion of the brake rotor 8, and then shown in FIG. The rotation transmission mechanism 9 for transmitting the rotation of the wheel hub 2 about the axis to the jig 3 and the grinding mechanism 11 for grinding the rotor surface 8b (the flange-shaped portion) of the brake rotor 8 are set as described above. Done.

More specifically, for example, as shown in FIG. 6, the rotation transmitting mechanism 9 sets the output shaft 11 driven by the motor 9 at a point coaxial with the wheel hub 1 and cures the output shaft 11 at the distal end. A structure for engaging the engaging portion 6 of the tool 3 is used. The grinding mechanism 10 has a structure in which a slider unit 12 having a pair of grinding tools 12a (corresponding to a grinding tool) facing each other at a predetermined interval is set on the side of the brake rotor 8.

As a result, the output shaft 11 driven by the motor is
, The wheel hub 1 and the brake rotor 8 are rotated about the axis, and then the pair of grinding tools 12a are slid from the side of the brake rotor 8 toward the center, thereby causing the brake rotor 8 to oscillate. Are ground by the tip at the tip of the grinding tool 12a to eliminate the circumferential thickness difference of the brake rotor 8, and the rotor surface 8b is corrected to a uniform thickness.

[0011]

Incidentally, it is desirable that the brake judder does not recur after the brake rotor 8 has been ground once.

However, although the brake rotor 8 has good rotor runout accuracy immediately after rotor grinding, the jig 3
Is removed from the brake rotor 8, a phenomenon occurs in which the surface runout is inclined in a direction opposite to the initial surface runout.

It has been found that the cause is related to dishing formed on the flange-like hub surface 1a of the wheel hub 1 which receives the brake rotor 8, as shown in FIG. 7 (a). Note that dishing refers to the degree of depression caused by grinding when the hub surface 1a of the wheel hub 1 is formed.

The relationship between the dishing and the runout will now be described.
Suppose that correction is performed by rotor grinding with the brake rotor 8 attached to the vehicle body.

At this time, the brake rotor 8 is
As shown in (2), the central portion is displaced following the shape of the dish of the wheel hub 1, and the rotor portion 8a on the outer peripheral side of the brake rotor 8 is inclined (runout).

In the rotor grinding, as shown in FIG. 7 (c), of the plurality of hub bolts 2 protruding from the center of the brake rotor 8, the jig 3 is used by using one hub bolt 2. Fastening is performed using the hub nut 7, and the hub nuts 7 are further fastened to the remaining hub bolts 2, respectively. Then, the rotation transmission mechanism 9 and the grinding mechanism 10 are set as described above.

However, at this time, the jig 3 is locally (one) fastened to the wheel hub 1 and is added because the contact area of the jig 3 in contact with the rotor portion is larger than the hub nut 7. The center of gravity of the tightening force is the center of the wheel hub 1 (the center of the brake rotor 8), that is, the wheel hub 1
Shows the behavior of the spindle 14 that is assembled from the center. Therefore, under the influence of the tightening force applied to the displaced point, the hub surface 1a of the wheel hub 1 and the brake rotor 8
Is deformed in the direction in which the dishing is reduced (in the direction in which the dishing becomes flat), and the attitude of the rotor portion 8a of the brake rotor 8 is inclined to follow the deformation.

The brake rotor 8 is subjected to rotor grinding by the rotation transmitting mechanism 9 and the grinding mechanism 10 while this part is in a tilted state (deformation), and the rotor grinding is completed as shown in FIG. Immediately after, the thickness difference in the circumferential direction disappears,
The rotor surface 8b is corrected to a uniform thickness (surface run-out is eliminated).

However, when the jig 3 is removed from the brake rotor 8, the deformed hub surface portion of the wheel hub 1 returns as shown in FIG. This represents a behavior of inclining (changing) in a direction opposite to that when the jig 3 is attached.

For this reason, even if the grinding of the rotor 13 is finished and the wheel 13 with the tire is mounted on the brake rotor 8 by using the hub nut 7 as shown in FIG. No. 8 has a strong tendency to cause uneven wear due to the inclination in the reverse direction, and the brake judder is likely to recur.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a method and apparatus for grinding a brake rotor in which a corrected rotor surface does not change even if a jig is removed. Is to provide.

[0022]

According to a first aspect of the present invention, there is provided a method for grinding a brake rotor, wherein when a jig is mounted on the brake rotor, the center of gravity of the tightening force of all fastening members acting on the brake rotor is reduced. By tightening so as to match the center of the wheel hub, the inclination of the hub surface due to the fact that the center of gravity of the fastening force of the jig and the fastening force by the fastening member other than the jig is shifted from the axis of the wheel hub Rotor grinding without changing the runout of the brake rotor.

Accordingly, even if the jig is removed, the posture of the rotor surface of the brake rotor does not change, and recurrence of the brake judder can be prevented.

According to a second aspect of the present invention, there is provided a method for grinding a brake rotor.
Furthermore, the jig is fastened by interposing a spacer part with a rotor contact area of the same size as the fastening member between the jig and the brake jig so that such rotor grinding can be realized by a simple operation. All the fastening members including the fastening member to be fastened are tightened with a predetermined tightening torque.

The brake rotor grinding device according to the third aspect of the present invention uses a fastening member by utilizing a part of a plurality of wheel fastening portions of the brake rotor so that an apparatus suitable for such a grinding method is realized. A jig is fastened by interposing a spacer portion having a rotor contact portion of the same size as the brake rotor with the brake rotor, and fastening members for fastening the jigs to the remaining wheel fastening portions are fastened with the same fastening force. Therefore, a structure was adopted in which the side surface of the brake rotor was ground with a grinding tool.

According to a preferred embodiment of the present invention, the wheel fastening portion is formed by a hub bolt protruding from the center of the brake rotor, and the fastening member is formed by a hub nut combined with the hub bolt. .
A washer having a rotor contact surface equivalent to the rotor contact area of a hub nut serving as a spacer is sandwiched and fastened between the jig and the brake rotor.

B. A rotor contact portion having a rotor contact surface equivalent to a rotor contact area of a hub nut serving as a spacer portion is integrally formed at an opening edge of a bolt insertion hole facing the brake rotor side of the jig. It is desirable to consider the structural point and the cost point.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described based on a first embodiment shown in FIGS.

The feature of this embodiment is that when the jig 3 is mounted on the brake rotor 8 using the hub bolts 2, the center of gravity of the tightening force of all the hub nuts 7 acting on the brake rotor 8 is set at the center of the wheel hub 1 (center of the spindle). The point is to match the center.

Therefore, in this embodiment, as shown in FIGS. 1 to 3, the jig 3 is
When the hub nut 7 is fastened to the central portion of the brake rotor 8, a structure is adopted in which, for example, a washer 15 is sandwiched between the hub 8 and the brake rotor 8 as a spacer. The other parts are the same as those of the brake rotor grinding method and the brake grinding apparatus described with reference to FIGS. 5 to 7, and therefore, of the respective parts of FIGS. The description is omitted.

Specifically, the washer 15 which is a feature of the present embodiment is a hub nut 7 screwed into the hub bolt 2.
A washer having a contact area of the same size as the contact area of the tip of the rotor is selected. This washer 15
When the jig 3 is attached using the hub bolt 2 (one), the jig 3 is interposed between the jig 3 and the brake rotor 8 through the hub bolt 2 as shown in FIGS. is there. And, with the intervention of the washer 15,
A condition is established in which the center of gravity of the tightening force of all hub nuts 7 and the center of the wheel hub 1 (center of the spindle) match,
The rotor grinding can be performed without any change in the surface runout.

The working steps up to the end of the rotor grinding are shown in order in FIGS.

A description will be given of a grinding method according to this work process. Now, it is assumed that the run-out of the brake rotor 8 is corrected by rotor grinding with the brake rotor 8 attached to the vehicle body.

At this time, the brake rotor 8 is
As shown in (a), the central portion is displaced following the dish shape of the wheel hub 1.

In order to start the rotor grinding, first, the jig 3 is attached to the brake rotor 8.

At this time, as shown in FIG. 1, a washer 15 and a jig 3 are sequentially inserted through one hub bolt 2 among a plurality of hub bolts 2, and then the bolt ends passing through the jig 3 The hub nut 7 is fitted, and the hub nut 7 is tightened with a specified tightening torque. Furthermore, the hub nuts 7 are respectively fitted to the remaining hub bolts 2 so that the respective portions of the brake rotor 8 are not distorted by the fastening of the jigs 3, and the same tightening torque as when the jigs 3 are fastened to the hub nuts 7. Tighten with.

At this time, the tightening force of the hub nut 7 applied to the jig 3 is transmitted through the washer 15 having the same contact area as the contact area of the tip of the hub nut 7 with the rotor.
The hub bolt 2 is applied to the brake rotor 8 from a point. Further, the tightening force of the other hub nut 7 is applied to the brake rotor 8 from the point where the remaining hub bolt 2 exists, through the tip of the hub nut 7 that contacts the brake rotor 8.

Thus, from the point of each hub bolt 2,
Under the same conditions (the rotor contact area and the tightening force are the same), a tightening force is applied to the wheel hub 1 and the brake rotor 8. As a result, a behavior that suppresses the displacement of the center of gravity, that is, a behavior in which the center of gravity of the tightening force of all the hub nuts 7 matches the center of the wheel hub 1 (center of the spindle) appears.

By suppressing the displacement of the center of gravity, the hub surface 1a
3B, the behavior of the rotor surface 1b does not change, that is, the behavior of changing the surface vibration of the rotor surface 8b does not change. It does not occur.

After that, when the rotor surfaces 8b on both sides of the brake rotor 8 are cut by using the rotation transmitting mechanism 9 and the cutting mechanism 10, as shown in FIG.
Rotor grinding is performed in a state where there is no unnecessary deformation (inclination), and the thickness difference in the circumferential direction is eliminated (thickness dimension: uniform).

Therefore, even if the jig 3 is removed from the brake rotor 8 after the rotor grinding, the wheel hub 1 and the brake rotor 8 have no stress that deforms the rotor portion 8a. As shown in ()), the posture of the rotor surface 8b corrected by cutting does not need to be displaced or deformed, and the surface runout accuracy is maintained as it is.

That is, after the rotor grinding, the brake rotor 8
In addition, even when the vehicle is run with the wheel 13 with the tire attached thereto, unnecessary uneven wear does not occur.

Accordingly, it is possible to provide a rotor grinding method and a rotor grinding apparatus which are effective in preventing the recurrence of brake judder. In particular, the suppression of the change in the runout is a simple operation because it is only necessary to use a general-purpose part called the washer 15 and to tighten all the hub nuts 7 with the same tightening torque. Moreover, since it is simple in structure and inexpensive in cost, it is suitable for a grinding device that performs on-car race.

FIG. 4 shows a second embodiment of the present invention.

This embodiment shows an example in which an annular seat portion 16 (corresponding to a rotor contact portion) serving as a spacer portion is integrally provided on the surface of the jig 3 which contacts the rotor.

The seat 16 is formed, for example, with the through hole 5 a of the jig 3.
A structure in which an annular contact portion having the same rotor contact area as that of the hub nut 7 is formed integrally with the opening edge of the hub nut 7 is employed. A seat 16 protruding from the rear surface of the jig 3 is interposed between the jig 3 and the brake rotor 8.

With such a spacer structure, the same effects as those of the first embodiment can be obtained. However, FIGS. 4 (a) to 4 (d)
In FIG. 7, the same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

The present invention is not limited to the above-described embodiment, and may be implemented with various modifications without departing from the gist of the present invention. For example, in the above-described embodiment, the structure in which the hub nut is screwed into the hub bolt protruding from the brake rotor to mount the wheel is described as an example.However, the invention is not limited to this, and the hub bolt is screwed into the screw hole formed in the brake rotor to mount the wheel. The present invention may be applied to such a structure. Of course, the present invention can also be applied to a rotor grinding method or a rotor grinding apparatus in which a dedicated receiving member is combined with the tip of the hub nut and fastened. That is, in this case, since the receiving member becomes a part of the tightening member, a washer or a seat having a contact area equal to the contact area of the receiving member with the rotor may be used.

[0049]

As described above, according to the present invention, even when a jig is mounted on the brake rotor, the hub surface and the rotor portion are not locally deformed. After finishing the jig, even if the jig is removed, the rotor surface corrected by cutting can keep the runout accuracy without displacing or deforming, and the brake caused by the change in the runout of the brake rotor This prevents judder from recurring.

In addition, since the runout accuracy of the rotor surface is maintained by using the spacer portion, the rotor can be ground with a simple operation, and the rotor grinding apparatus is effective in terms of structure and cost. .

[Brief description of the drawings]

FIG. 1 is a perspective view for explaining how to attach a jig using a spacer portion according to a rotor grinding method of a first embodiment of the present invention.

FIG. 2 is a perspective view for explaining the structure of a rotor grinding device used in the rotor grinding method.

FIG. 3 is a sectional view for sequentially explaining the steps until the rotor grinding is performed without changing the rotor surface by the rotor grinding method.

FIG. 4 is a cross-sectional view for sequentially explaining a process until rotor grinding is performed without changing a rotor surface, which is a main part of a second embodiment of the present invention.

FIG. 5 is a perspective view illustrating a mounting structure of a jig used in a conventional on-car race.

FIG. 6 is a perspective view showing a state where the rotor surface of the brake rotor is ground using the jig.

FIG. 7 is a sectional view for sequentially explaining a rotor surface of the rotor is ground by the grinding and a wheel is attached after the grinding.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Wheel hub 2 ... Hub bolt (wheel tightening part) 3 ... Jig 5 ... Fixed seat 6 ... Engagement part 7 ... Hub nut (fastening member) 8 ... Brake rotor 12a ... Grinding tool (grinding tool) 15, 16 ... Washer , Seat (spacer).

Continued on the front page F term (reference) 3C034 AA13 BB71 CB11 DD20 3C043 BC00 CC01 DD05 EE04 3C045 BA40 CA04 DA01 FE20 3J058 AA48 AA53 AA62 BA75 CB26 CB27 FA01

Claims (3)

[Claims] 1. A brake rotor with a wheel hub,
Utilizing a part of the plurality of wheel fastening portions formed on the brake rotor, using a fastening member, fastening a jig, and fastening the fastening members to the remaining wheel fastening portions, respectively,
A brake rotor grinding method for rotating the brake rotor around an axis using the jig, and grinding a side surface of the rotating brake rotor with a grinder, wherein the jig is attached to the brake rotor, A method of grinding a brake rotor, wherein the center of gravity of the tightening force of all the fastening members acting on the brake rotor is fastened so as to coincide with the center of the wheel hub. 2. A relation in which the center of gravity of the tightening force of all the fastening members coincides with the center of the wheel hub is as follows: the jig has an area per rotor between the brake rotor and the same size as the fastening member. All the fastening members including the fastening member for fastening the jig are fastened with the spacer portion interposed therebetween,
2. The method according to claim 1, wherein the method is performed by being tightened with a predetermined tightening torque. 3. A brake rotor with a wheel hub,
Utilizing a part of a plurality of wheel fastening portions formed on the brake rotor, using a fastening member, fastening a jig, and fastening the fastening member to the remaining wheel fastening portion, equivalent to when the jig is fastened. A brake rotor grinding apparatus that, after being fastened by a fastening force, rotates the brake rotor around an axis using the jig, and grinds a side surface of the rotating brake rotor with a grinder. A brake rotor grinding apparatus characterized in that a spacer portion having a rotor contact area of the same size as the fastening member is interposed between the rotor portion and the rotor portion in contact with the same.