JPS6142771Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a roller burnishing device that burnishes the inner surface of a circular hole by rolling and pressing a roller against the inner surface of the hole.

In this type of device, a plurality of burnishing rollers are usually arranged at equal angular intervals around the main shaft, and are held by a retainer, which is a cylindrical member rotatably fitted to the main shaft. At least the part of the main shaft around which the rollers are arranged has a plurality of flat parts parallel to the axis formed at equal angular intervals on the outer peripheral surface of the cylinder, and a part of the outer peripheral surface of the cylinder is formed between each of these flat parts. A certain cylindrical surface portion remains and is formed into a polygonal column shape. While the flat part of the main shaft corresponds to the roller, the roller does not perform the burnishing action, and when the cylindrical surface part of the main shaft corresponds to the roller, this cylindrical surface pushes the roller outward in the radial direction. , the roller rolls on the inner surface of the workpiece while being strongly pressed against it, producing a burnishing effect.

Conventionally, in such a burnishing device,
For example, when the number of rollers is six, the number of cylindrical surfaces on the polygonal columnar portion of the main shaft is usually 12, and the number of cylindrical surfaces is usually an integral multiple of the number of rollers. Therefore, a state in which all the rollers ride on the cylindrical surface part and perform a burnishing action and a state in which all rollers do not perform a burnishing action in response to the flat part appear alternately, and the spindle or the workpiece is rotated. There was a problem that the drive torque required to do this fluctuated greatly, making machining unstable. In addition, since all the rollers perform the burnishing action at the same time, if the inner diameter of the pilot hole of the workpiece is too small, extremely difficult machining will be performed, making it difficult to stabilize the dimensional accuracy of the finished surface. In addition, the time required for machining becomes longer, and in order to avoid this, it is necessary to extremely strictly control the dimensional accuracy of the prepared hole.

The present invention eliminates these drawbacks of the conventional technology,
A product with small fluctuations in the drive torque for rotating the spindle or workpiece, and which allows burnishing to be performed easily even if the dimensional accuracy control of the pilot hole is relatively loose, and which also has stable dimensional accuracy. The purpose of this invention is to provide a roller burnishing device for inner surface processing that can obtain the following: The reason lies in the fact that the number was determined to be a combination of two numbers that do not exist.

In this way, when one roller is located at the center of the cylindrical surface, another roller that is exactly the same will not be located at the center of the cylindrical surface, but will mainly perform a burnishing action. There will always be one roller. In other words, as the main shaft and the workpiece rotate relative to each other, different rollers ride on the cylindrical surface portion one after another at regular intervals to perform a continuous burnishing action. However, depending on how the width of the cylindrical surface is selected, it is possible that when one roller is located at the center of the cylindrical surface, another roller rides on the edge of the cylindrical surface. Even in this case, the plurality of rollers do not ride on the cylindrical surface portion at the same time, but rather ride on the cylindrical surface portion with a slight time lag, so that torque fluctuations can be suppressed to be significantly smaller than in the past. In addition, there is always one roller that mainly performs the burnishing action, and even when two rollers ride on the cylindrical surface, it is necessary to ensure that these two rollers are exactly spaced apart in the diametrical direction of the main shaft. Since the burnishing effect of the roller corresponding to the cylindrical surface is reduced by the radial deflection of the spindle, and unreasonable machining is not performed, the dimension of the prepared hole is slightly too small. Even in such cases, there is no deterioration in dimensional accuracy or prolongation of processing time unlike in the conventional method.

Hereinafter, embodiments of the present invention will be described based on the drawings.

In FIG. 1, reference numeral 2 denotes a main shaft, which has a mounting flange 4 at its base end, and a positioning fitting part 6 protruding from the center of this flange 4. Main shaft 2
is positioned by fitting this positioning fitting part 6 into a fitting hole (not shown) provided at the center of the main shaft of the burnishing board, and as shown in Fig. It is fixed with bolts using a suitable number of dowel holes 8.

The main shaft 2 is provided with a prismatic portion 10 on the tip side.
As shown in FIG. 3, the prismatic portion 10 has eight flat portions 12 parallel to its axis formed at equal angular intervals on the outer peripheral surface of the cylinder, and a part of the outer peripheral surface of the cylinder is formed between each flat portion. Similarly, eight cylindrical surface portions 14 are left. First, a thrust bearing 16 is fitted into this prismatic portion 10, and then five rollers 1 are fitted.
A retainer 20 holding 8A to 18E is fitted, and a guide sleeve 22 is further fitted. The thrust bearing 16 has an inner ring 24 and an outer ring 26.
It consists of an appropriate number of balls 28 arranged between the rollers 18A to 1, and a retainer (not shown) that rotatably holds these balls.
It supports one end of 8E so that it can rotate easily. As is clear from FIGS. 4 and 5, the retainer 20 has an overall cylindrical shape,
In addition, five roller holding grooves 30 are formed from one end side in parallel to the axis. These roller holding grooves 30 are formed by forming five round holes parallel to the axis from one end of the cylindrical member, and then cutting and grinding the inner and outer peripheral surfaces of the cylindrical member.
The sides of these round holes communicate with the outer space and inner space of the cylindrical member, and the roller 18
A to 18E are formed to be rotatable and held so as to be movable by a minute amount in the diametrical direction. Therefore, a portion of the outer peripheral surface of the roller held in the roller holding groove 30 is attached to the retainer 2.
It is possible to protrude outward from the outer peripheral surface of the retainer 20 and inward from the inner peripheral surface of the retainer 20. Further, the guide sleeve 22 has an oil groove formed on its inner circumferential surface so that it can easily rotate on the prismatic portion 10, and has tapered surfaces 32 and 34 formed on both ends of its outer circumferential surface. can guide insertion of the burnishing device into the round hole of the workpiece. A set screw 36 is tightened and fixed to the most extreme part of the main shaft 2 via a spacer 38, and the guide sleeve 22, retainer 20, thrust bearing 16, etc. are attached to the prismatic part 10.
This prevents them from leaving.

The behavior of each roller when machining the inner surface of a round hole of a workpiece using the burnishing device configured as described above will be explained based on FIG. Assuming that the main shaft 10 is now rotated clockwise as shown by arrow P in FIG.
When the roller 18A is located at the center of the cylindrical surface portion 14, the roller 18C is about to ride on the cylindrical surface portion 14, and the roller 18D is on the contrary
It is slightly away from the. The other two rollers 18B and 18E are located approximately at the center of the flat portion 12. Therefore, roller 18A is actually performing the burnishing action, roller 18C is about to start the burnishing action, and roller 18D is
has just finished its burnishing action, and the remaining two rollers 18B and 18E are in a state where they are not performing their burnishing action at all.

If the main shaft 10 further rotates clockwise from this state, the rollers 18A and 18C will move to the cylindrical surface part 1.
4 and is in a state where it performs a burnishing action,
When the main shaft 10 further rotates clockwise, the roller 18C is located at the center of the cylindrical surface part 14, and the roller 18C is located at the center of the cylindrical surface part 14.
8A comes off the cylindrical surface part 14, and the roller 18E is about to ride on the cylindrical surface part 14.

In this way, in the burnishing device of this embodiment, at least one roller is always attached to the cylindrical surface portion 1.
4, and in most cases, two rollers contact the cylindrical surface portion 14 at the same time to perform the burnishing action. Each time the main shaft 10 rotates by a certain angle, the five rollers ride on the cylindrical surface part 14 one after another and start the burnishing action, so the fluctuation in the driving torque for rotating the main shaft 2 is extremely small.

Moreover, when only the roller 18A is in contact with the cylindrical surface portion 14, the burnishing effect of the roller 18A is reduced by bending the main shaft 10 in the direction shown by the arrow Q. When both rollers 18C are in contact with the cylindrical surface portion 14, the burnishing action of both rollers can be reduced by bending the main shaft 10 in the direction shown by the arrow R, so that the inner dimensions of the hole to be machined are optimized. Even if the size is smaller than the original condition, unreasonable burnishing is not performed, and the burnishing process is performed smoothly, making it possible to obtain a product with stable dimensional accuracy.

FIG. 6 shows another embodiment of the present invention.

In this example, the roller is 40A to 40A.
G, in total, are provided, and each main shaft prismatic portion 42 is provided with 12 flat portions 44 and 12 cylindrical surface portions 46. The other parts are the same as those in the previous embodiment, so illustration and description will be omitted.

Also in this embodiment, when the roller 40A is located at the center of the cylindrical surface part 46, the roller 40D is about to ride on the cylindrical surface part 46, and the roller 40A
0E is in a state slightly removed from the cylindrical surface part 46, and the other four rollers are all in positions corresponding to the flat part 44. Therefore, the same effects as in the embodiment described above can be obtained.

In the two embodiments detailed above, when one roller is located at the center of the cylindrical surface, one of the two rollers located farthest from the roller rides exactly on the cylindrical surface. The structure was such that the other side was slightly removed from the cylindrical surface. Configuring like this
The most desirable method is to smooth the relative rotational drive torque between the burnishing device and the workpiece, and to avoid unreasonable burnishing action by utilizing the deflection of the main shaft. If the number is determined to be a combination of two numbers that have no common divisor other than 1, it is possible to avoid two or more rollers from riding on the cylindrical surface at the same time. Thus, a certain effect of the present invention can be obtained.

Also, it is desirable to have more cylindrical surfaces in the polygonal column than the number of rollers from the viewpoint of ease of manufacturing, but by reversing the numbers, the number of cylindrical surfaces is greater than the number of rollers. It is also possible to reduce the amount. Furthermore, in the above two embodiments, the plane portions of the prismatic portions were each made up of several corners, in consideration of the ease of machining and dimension determination of the prismatic portions. It is also possible to have an odd number of surfaces.

It goes without saying that the present invention can be implemented in various modifications based on the knowledge of those skilled in the art without departing from the scope of the claims for utility model registration, in addition to the embodiments described in the specific examples above. be.

[Brief explanation of the drawing]

FIG. 1 is a front sectional view of a roller burnishing device for inner surface processing which is an embodiment of the present invention, and FIG.
The figure is also a left side view. FIG. 3 is an explanatory diagram showing the relationship between the main shaft prismatic portion and the rollers in the apparatus shown in FIG. 1. FIG. 4 is a front sectional view of the retainer used in the apparatus shown in FIG. 1, and FIG. 5 is a right side view. FIG. 6 is a diagram corresponding to FIG. 3 in another embodiment of the present invention. 2: Main axis, 10, 42: Prismatic part, 12, 4
4: Plane portion, 14, 46: Cylindrical surface portion, 18A~
E, 40A-G: Roller, 20: Retainer, 3
0: Roller holding groove.

Claims (1)

[Claims for Utility Model Registration] A plurality of flat parts parallel to the axis are formed at equal angular intervals on the outer peripheral surface of a cylinder, and a cylindrical surface part that is a part of the outer peripheral surface is left between each flat part. a main shaft having a polygonal columnar part; a plurality of burnishing rollers arranged on the outer periphery of the polygonal columnar part parallel to the axis of the polygonal columnar part at equal angular intervals; and rotatable to the outside of the polygonal columnar part. A member fitted to the cylindrical member, which allows all of the rollers to rotate and move minutely in the diametrical direction, and whose outer circumferential surface extends outward from the outer circumferential surface of the cylindrical member and from within the cylindrical member. and a retainer held so as to protrude inward from the circumferential surface, and the apparatus is inserted into a circular hole of a workpiece to perform burnishing on the inner circumferential surface of the hole, comprising: the number of burnishing rollers; A roller burnishing device for inner surface processing, characterized in that the number of cylindrical surface portions of the roller burnishing device is determined to be a combination of two numbers that have no common divisor other than 1.