JPH02269563A - Dressing device for honing stick - Google Patents

Abstract

PURPOSE:To prevent the angle portions of a honing stick from breaking off by forming the shaping face of a dresser as one with a radius of curvature smaller than that of the inner wall surface of a subject to be processed, which shaping face shapes the cutting face of the honing stick by means of its movement relative to the stick, and using the dresser to shape the honing stick and also to perform dressing work. CONSTITUTION:In processing the inner wall surface of a subject 1 (cylinder) to be processed made of hyper-eutectic aluminum alloy, a plurality of bar-shaped honing sticks 10 each made of an elastic stick are provided, and are each rotated and put in a reciprocating movement in its axial direction as it is expanded to the inner wall surface of the subject 1 to be processed, whereby the inner wall surface 4 is honed. The shaping face 17 of a dresser 16 which shapes the cutting face of each honing stick 10 by means of its movement relative to each stick 10 is formed with a radius of curvature smaller than that of the inner wall surface of the subject 1, and the dresser 16 is used to shape each honing stick and also to perform dressing work. As a result, the angle portions of each stick 10 are prevented from breaking off during honing process.

Description

Detailed Description of the Invention (Field of Application in Industry-1-) The present invention is a honing method for processing the inner wall surface of a workpiece made of an aluminum alloy with a high silicon (Sl) content using a honing stone made of an elastic grindstone. The present invention relates to a dressing device for a honing stone that performs shaping and dressing operations on the honing stone in a processing device.

(Prior Art) For example, conventionally, in the cylinder of an automobile engine, a cylinder block is formed from an aluminum alloy in order to reduce the weight of the engine and improve thermal conductivity, and a cast iron cylinder liner is fitted to this cylinder block. It was constructed by incorporating

As is well known, the inner wall surface of a workpiece such as a cylinder liner is processed by honing, and a honing pressurizing device 11 as shown in FIG. 6 is used.

The honing unit 13 equipped with this honing processing device 11 processes workpieces continuously]-It is incorporated into a part of the transfer line 12, and processes workpieces that have been subjected to a predetermined process in the previous process. Honing unit 1
After being carried into the unit 13 and subjected to honing processing in the unit 13, the workpiece is transported to the next process.

A honing head 5 for grinding a workpiece is provided on the main body 11a of the honing device 1j- via a joint 14. As shown in FIG. 7, this honing head 5 has a main body 6 and a bushing rod 7 that is movable in the axial direction. A tapered cone 8 having a tapered surface 8a is attached to the bushing rod 7. On the outer periphery of the board 6, a stone holder 9 holding a rod-shaped grindstone 10 is installed.
The tapered cone 8 is attached with its tapered surface 9a in contact with the tapered surface 8a of the tapered cone 8.

A pressure device (not shown) is connected to the bushing rod 7 to move the rod 7 up and down using hydraulic pressure or the like. In addition, the main body 11a of the honing tool 11 includes
A drive motor that rotates the body 6 and a hydraulic device that causes it to reciprocate in the axial direction are built in.

Then, when the bushing rod 7 is pushed down by the pressurizing device, the taper cone 8 is pushed down, and its tapered surface 8a comes into contact with the tapered surface 9a of the stone holder 9, and the halter 9 is evenly moved outward. . Therefore, the grindstone 1o also protrudes outward and comes into pressure contact with the inner wall surface 4 of the workpiece 1. Furthermore, by controlling the amount by which the bushing rod 7 is pushed down by 1, the pressing force or expansion pressure of the grindstone 1o can be controlled. In this manner, the inner wall surface 4 of the workpiece 1 is machined by applying a predetermined expansion pressure to the grindstone 1o and reciprocating the honing head 5 in the axial direction while rotating.

By the way, in the case of a cylinder constructed by fitting the cylinder liner into the cylinder block, there is a problem that when fitting the cylinder liner, the adhesion between the two may not be good or deformation may occur. Ta.

Therefore, in recent years, attempts have been made to manufacture the cylinder itself from an aluminum alloy without using a cylinder liner, thereby further reducing the weight of the engine and improving thermal conductivity.

As disclosed in Japanese Patent Application Laid-open No. 5'7-9900, etc., the aluminum alloy used for the Kono type cylinder is a hypereutectic alloy with a silicon content of about 16 to 18% by weight. Al-8i alloy is known as Al-8i alloy, in which silicon particles are raised from the inner wall surface of the cylinder, and the silicon particles improve wear resistance, and the recesses between the raised silicon particles ensure that lubricating oil is retained. I have to.

JP-A-52-147,392 discloses that the inner wall surface of the cylinder made of the hypereutectic aluminum alloy is
It has been proposed to carry out honing using a honing stone made of an elastic grindstone.

(Problem to be Solved by the Invention) However, since this elastic grindstone is made of rubber bond or resin bond and is relatively soft, the corners may fall off or be scraped during honing. There were times when I did. Therefore, there is a drawback that the sharp corners cause processing defects such as crushing or falling off of silicon particles.

In addition, when honing a workpiece made of cast iron, etc., there is no need to dress the grindstone because the grinding process is performed by the self-sharpening action of the grindstone. When honing with a grindstone, this elastic grindstone may become clogged, crushed, or
Alternatively, the abrasive grains are likely to be crushed, and the grindstone 1o and the inner wall surface 4
The quality of the inner wall surface 4 was not good because the contact condition with the inner wall surface 4 was impaired.

The present invention has been made in view of the problems of the prior art, and is aimed at processing the surface of a workpiece made of a hypereutectic aluminum alloy using a honing stone made of an elastic grindstone. It is an object of the present invention to provide a dressing device for a honing whetstone that shapes a cutting surface to prevent chipping and the like and at the same time performs a dressing operation on the whetstone.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides the following advantages:
It has multiple rod-shaped honing wheels made of elastic wheels.
In a honing processing device that processes the inner wall surface by rotating and reciprocating in the axial direction while expanding each honing stone toward the inner wall surface, the honing stone The shaping surface of a dresser for shaping the cut surface of the honing stone is formed to have a smaller radius of curvature than the radius of curvature of the inner wall surface of the workpiece, and the dresser shapes the honing stone and performs dressing work. This is a dressing device for honing wheels.

(Operation) Due to the relative movement between the honing stone and the dresser,
The cutting surface of the grindstone is shaped to have a radius of curvature smaller than the radius of curvature of the inner wall surface of the workpiece, and a dressing operation is also performed. Therefore, problems such as chipping of the corners of the whetstone do not occur during honing, and since dressing work is performed, the life of the whetstone is extended, and the workpiece is finished with a high-quality finish. be exposed.

(Example) Hereinafter, a dressing device for a honing grindstone according to the present invention will be described based on the drawings.

Fig. 1.2 is a cross-sectional view showing one embodiment of the honing stone dressing device of the present invention, Fig. 3 is a cross-sectional view for explaining its operation, and Fig. 4 is a cross-sectional view showing another embodiment. FIG. 5 is a sectional view showing still another embodiment, and FIG.
The same reference numerals are given to the members common to those shown in FIGS.

As shown in FIG. 1, the honing device 11 includes a plurality of bar-shaped honing stones 10 made of elastic grindstones attached to the outer circumference of the honing head 5, and each honing stone 10 is attached to the inner wall surface 4 side of the cylinder 1. By rotating and reciprocating in the axial direction while expanding, the inner wall surface 4
It is designed to process.

Then, the dressing device 15 for the honing whetstone changes the honing whetstone 1 by the relative movement with the honing whetstone 10.
A dresser] 6 for shaping the cut surface 10a of the honing wheel 10 is incorporated into the honing device 11, and the dresser 6 shapes the cut surface 10a of the honing wheel 10.
In addition to shaping the area a, dressing work is also performed.

The shaping surface 17 of the dresser 6 is formed to have a radius of curvature R which is smaller than the radius of curvature R of the inner wall surface 4 of the cylinder. For example, the bore diameter of the cylinder is 2R = 80m.
m, the inner diameter of the shaping surface 17 of the dresser 6 is 2R1
= approximately 75 mm is suitable.

Further, the dresser 16 is rotatably provided with respect to the honing head 5, so that the grindstone 10 and the dresser 6 can move relative to each other. Note that it is sufficient that the grindstone 10 and the dresser 6 can move relative to each other (
For example, the honing head 5 may be rotated while the drain/fusa 16 side is fixed, or both 5 and 16 may be rotated relative to each other.

Next, the operation of this embodiment will be explained.

When a new honing stone 10 is attached to the honing head 5, or when the cutting progresses and a phenomenon such as clogging occurs in the grindstone 10, the grindstone 10 is expanded toward the shaping surface 17 of the dresser 16. , as shown in FIG. 2, the honing head 5 and dresser 16 are rotated relative to each other.

Then, the cutting surface 10a having the radius of curvature R1 is formed on the honing whetstone 10, and a dressing operation for removing chips and the like is performed.

Next, a case will be described in which the inner wall surface 4 of the cylinder 1 is honed using the honing whetstone 10 that has completed the shaping and dressing work of the cut surface 10a in this manner.

At this time, as shown in FIG. 3, the radius of curvature R of the grindstone 10
1 is smaller than the radius of curvature R of the bore of the cylinder 1, so the corners of the grindstone 10 are spaced apart from the inner wall surface 4. Even if honing is performed by rotating the honing head 5 under this condition, the corners do not come into direct contact with the inner wall surface 4, so defects such as cracks will not occur in the corners K. Moreover, since there are no chips on the corners, there is no risk of scratching the inner wall surface 4, and a high-quality machined surface can be obtained.

Furthermore, since dressing work is done at the same time, grinding wheel 1
The contact state between the cut surface 10a of the cylinder 1 and the inner wall surface 4 is always good, and this also makes it possible to finish the inner wall surface 4 of the cylinder 1 with high quality.

Incidentally, in the embodiment described above, the shaping and dressing work of the cutting surface 10a is performed by the relative rotational movement between the grindstone 10 and the dresser 16, but the present invention is not limited to this embodiment. It is sufficient if the shaping and dressing work of the cutting surface 10a can be performed by the relative movement of both 10 and 16. For example, as shown in FIG.
A concave groove 18 with a radius of curvature R1 is formed on the shaping surface 17 of the cutting surface 10a, and a relative axial movement of 1° 0.16 is applied to the cutting surface 10a, thereby shaping and dressing the cutting surface 10a. good. Further, as shown in FIG. 5, the radius of curvature of the edge of the groove 19 having the radius of curvature R2 is set to
3 may be formed. In this way, the deviation causes the corners of the grindstone 10 to be further away from the inner wall surface 4, making it possible to further prevent defects such as chips in the corners.

Furthermore, as a relative movement between the grindstone 10 and the dresser 16,
Ultrasonic vibration may be applied to at least one of these.

(Effects of the Invention) As explained below, in processing the inner wall surface of a workpiece made of a hypereutectic aluminum alloy, the present invention includes a plurality of rod-shaped honing wheels made of elastic grinding wheels, and each honing In a honing device that processes the inner wall surface by rotating and reciprocating the grindstone in the axial direction while extending it toward the inner wall surface, the grindstone cuts the honing stone by relative movement with the honing stone. J'i
forming the shaping surface of the dresser for shaping the l1 surface to have a smaller radius of curvature than the radius of curvature of the inner wall surface of the workpiece]-
2. However, since this is a honing stone dressing device in which the dresser shapes and dresses the honing stone, it is possible to prevent chipping of the corners of the honing stone, etc., and at the same time, dressing the honing stone. Since the contact state between the cut surface and the inner wall surface can always be maintained in a good state during the work, the inner wall surface of the workpiece can be finished with high quality, which is a great practical effect.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment of the honing stone dressing device of the present invention, FIG. 2 is a sectional view taken along the line ■-■ in FIG. 1, and FIG. 3 is the operation of the same embodiment. 4 is a sectional view showing another embodiment, FIG. 5 is a sectional view showing still another embodiment, and FIG. 6 is a configuration showing a general honing device. 7 are schematic cross-sectional views of a honing head for explaining honing processing. ... Cylinder (workpiece) ... Honing head, ... Honing grindstone, ... Dressing device, ... Shaping surface. 10a... Cutting surface, 16... Dresser,

Claims (1)

[Claims] When processing the inner wall surface of a workpiece made of a hypereutectic aluminum alloy, a plurality of rod-shaped honing stones made of elastic grinding stones are used, and each honing stone is rotated and axially expanded while expanding toward the inner wall surface. In the honing device which processes the inner wall surface by reciprocating motion, the shaping surface of the dresser, which shapes the cut surface of the honing stone by relative movement with the honing stone, is connected to the cutting surface of the workpiece. A dressing device for a honing stone, characterized in that the honing stone is formed to have a radius of curvature smaller than the radius of curvature of an inner wall surface, and the dresser shapes the honing stone and performs dressing work.