JPH09277156A - Method of honing head grinding wheel formation, ground grinding wheel therewith and grinding wheel forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve forming accuracy by giving good running-in against the inner periphery of a work processing hole to a new grinding wheel mounted on a honing head. SOLUTION: In conducting grinding work for grinding off the angular part of a new grinding wheel 3 used in a honing head, a grinding wheel 5 to be ground is used, which is provided with a cylinder inner surface 5H of the same shape as a work to be processed with the honing head 1. With the grinding wheel 3 pressed against the grinding wheel 5 to be ground by extendedly-moving it, the honing head 1 is rotated, and the grinding wheel 3 is brought into sliding contact with the cylinder inner surface 5H of the grinding wheel 5 to be ground.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is to remove a corner portion of a grindstone by sliding a new grindstone provided on an outer peripheral portion of a honing head and a grindstone to be ground into sliding contact with each other. TECHNICAL FIELD The present invention relates to a method for forming a grindstone for a honing head that improves the familiarity of the grindstone with respect to the wheel, a grindstone for use in this method, and a grindstone forming apparatus.

[0002]

SUMMARY OF THE INVENTION It is an object of the present invention to improve the precision of a molding operation for making a new grindstone provided on a honing head more familiar to a work surface of a work.

[0003]

In order to achieve the above object, the present invention is, firstly, to provide a new grinding stone, which is provided on the outer peripheral portion of a honing head and which is not used yet, to be processed by the honing head. While pressing against the cylindrical inner surface of the grindstone having a cylindrical inner surface of the same shape, the honing head and the grindstone are relatively rotated, by sliding contact between the grindstone and the grindstone, the grindstone This is a method for forming a grindstone by grinding and removing the corner portions of the grindstone.

According to the above-mentioned method for forming a grindstone, the grindstone of the honing head makes sliding contact with the inner surface of the cylinder having the same shape as the work of the grindstone, so that the corners of the grindstone are ground away and the tip surface thereof is removed. Is a convex curved surface that is familiar to the inner surface of the cylinder of the work. Further, since the grindstone is molded in a state where it is mounted on the honing head, there is no rattling in the circumferential direction during the molding work, and the molding accuracy is improved.

Secondly, in the first grindstone forming method, a new grindstone of the honing head is pressed against the inner surface of the cylinder of the material to be ground having the same cylindrical inner surface as that of the grindstone to be ground. The honing head and the material to be ground are relatively rotated, and the grinding stone and the material to be ground are brought into sliding contact with each other to complete the forming finish after the grindstone is formed by the grindstone to be ground. As a result, the tip surface of the grindstone becomes more familiar with the inner surface of the cylinder of the work.

Thirdly, in a grindstone to be ground, which is slidably in contact with a new grindstone before use provided on an outer peripheral portion of a honing head and grinds and removes a corner portion of the grindstone to form the grindstone, An inner surface of a cylinder having substantially the same shape as the work to be machined by the honing head is provided, and the inner surface of the cylinder serves as a sliding contact surface with the grindstone. As a result, the grindstone of the honing head comes into sliding contact with the inner surface of the cylinder having the same shape as the work piece of the grindstone, so that the corners of the grindstone are ground away and the tip surface thereof becomes familiar with the inner surface of the work cylinder. It becomes a convex curved surface.

Fourthly, in the third grindstone to be ground, hard boron nitride is provided on the sliding contact surface of the honing head with the grindstone. As a result, the work of forming the grindstone is efficiently performed, and the life of the grindstone to be ground is extended.

Fifth, a honing head having a grindstone on the outer periphery and capable of rotating and moving in the axial direction is in sliding contact with the grindstone in the circumferential direction, and the corners of the grindstone are ground away to form the grindstone. In a grindstone forming apparatus including a grindstone to be ground, the grindstone to be ground has a concave curved surface having substantially the same curvature as the inner surface of the cylinder of the workpiece processed by the honing head, and a part of the inner surface of the cylinder in the circumferential direction. And is movable by a first drive mechanism between a protruding position capable of contacting the tip surface of the grindstone of the honing head and a retracted position away from the tip surface. Another part of the inner surface of the cylinder in the circumferential direction is formed to provide a work material of the same material as the work, and the work material has a concave curved surface having substantially the same curvature as the work inner surface of the cylinder, and By the drive mechanism of 2, the horn A projecting position that can contact the front end surface of the grindstone Guheddo, it is movable between a retracted position away from the distal end surface.

According to the above construction, by operating the first drive mechanism, the grindstone to be ground is brought closer to the grindstone of the rotating honing head and brought into the projecting position. It makes sliding contact with the inner surface of the cylinder of the grinding wheel, the corners are ground and removed, and the tip surface becomes a convex curved surface that is familiar to the inner surface of the cylinder of the workpiece. Next, the first drive mechanism is operated to separate the grindstone from the grindstone of the honing head, and subsequently the second drive mechanism is operated to rotate the workpiece to be ground. Of the honing head is brought closer to the grindstone of the honing head to be in a protruding position, whereby the grindstone of the honing head is brought into sliding contact with the inner surface of the cylinder of the work to be ground, and the grindstone is shaped and finished.

Sixth, in the fifth structure, boron nitride is provided on the sliding contact surface of the grindstone to be ground with the grindstone of the honing head. As a result, the work of forming the grindstone is efficiently performed, and the grindstone to be ground has a long life.

[0011]

According to the first aspect of the present invention, the grindstone of the honing head makes sliding contact with the inner surface of the cylinder having the same shape as the work of the grindstone, whereby the corners of the grindstone are ground and removed. The tip surface of the grindstone is a convex curved surface that is familiar to the inner surface of the cylinder of the workpiece, and honing processing after the grindstone molding can be performed accurately. Further, since the grindstone is molded in a state where it is mounted on the honing head, there is no rattling in the circumferential direction during the molding work, and the molding accuracy can be improved.

According to the second aspect of the present invention, following the forming operation of the grindstone using the grindstone, the grindstone is brought into sliding contact with the inner surface of the cylinder of the work piece having the same shape and the same material. , The honing head's grinding stone is finished
As a result, the tip surface of the grindstone becomes more familiar with the inner surface of the cylinder of the work.

According to the third invention, the grindstone for forming the grindstone of the honing head is provided with the inner surface of the cylinder having the same shape as the work to be machined by the honing head. The tip surface becomes a convex curved surface that is familiar to the inner surface of the cylinder of the workpiece, and honing processing after the grinding stone molding can be performed with high accuracy.

According to the fourth aspect of the present invention, since boron nitride is provided on the sliding contact surface of the honing head with the grindstone, the grindstone can be efficiently formed and the life of the grindstone to be ground can be increased. it can.

According to the fifth aspect of the present invention, the grinding stone of the honing head can be formed by the first drive mechanism with the grindstone to be ground as the protruding position, and the second drive mechanism allows the workpiece to be ground at the protruding position. As a result, the grindstone of the honing head can be shaped and finished, and the grindstone shaping and the subsequent shaping and finishing can be performed in a short time.

According to the sixth aspect of the present invention, since boron nitride is provided on the sliding contact surface of the grindstone to be grinded with the grindstone of the honing head, the grinding stone can be efficiently formed.
The life of the grindstone to be ground can be extended.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, a cylindrical grindstone 5 for forming a grindstone is used for a plurality of grindstones 3 provided on the outer peripheral portion of the honing head 1 to improve the familiarity of the grindstone 3 with the work surface. FIG. 2 is a front sectional view showing a state where the grindstone 3 is being molded, and FIG. 2 is a plan sectional view of FIG. 1.

FIG. 3 is a sectional view showing a state in which the honing head 1 described above is used to perform the honing processing on the processing hole H provided in the work W. The honing head 1 includes a cylindrical head body 9 having an upper end provided with a shank 9S as a mounting portion for a spindle 7 provided on a honing machine (not shown). This head body 9
In the circumferential direction, a plurality of slits 11 are provided at appropriate intervals, and each slit 11 is provided with a grindstone shoe 13 provided with the above-described grindstone 3 on the outer side so as to be movable in the radial direction (radial direction). is there.

Each whetstone shoe 13 is constantly urged radially inward by the action of an appropriately provided ring-shaped spring 15.

On the outer peripheral surface of the head body 9, a plurality of guide members 17 made of a super hard guide are provided at appropriate intervals, and a suitable number of guide members 17 are provided with the guide members 17.
There is provided an air nozzle 19 as a measuring portion of an air micrometer for measuring a clearance C between the surface 17F of the above and the inner peripheral surface HF which is the inner surface of the cylinder of the processing hole H.

Inside the head main body 9, there is provided a rod 21 which is movable in the axial direction of the head main body 9, and the rod 21 pushes each of the grindstone shoes 13 radially outward to expand it. A widening taper portion 23 is provided for this purpose. The upper end of the rod 21 projects into the shank 9S of the head body 9, and the flange portion 25 attached to the rod 21
The rod 21 is always biased upward by the action of the spring 27 mounted between the shank 9S and the shank 9S.

In the structure as described above, the head body 9
After mounting the shank 9S on the spindle 7 of the honing machine, the honing head 1 is inserted into the machining hole H of the work W, the spindle 7 is rotated and moved up and down, and a hydraulic cylinder (not shown) provided on the honing machine. By lowering the rod 21 by means of a piston rod 28 that can move up and down,
By the action of the expanding taper portion 23, it is moved radially outward against the spring 15. As each grindstone shoe 13 is moved radially outward and expanded, the grindstone 3 provided on each grindstone shoe 13 is pressed against the inner peripheral surface HF of the machining hole H, and honing of the machining hole H is performed. .

When performing the honing as described above, the inner diameter of the processing hole H is measured. At this time, air is jetted from the air nozzle 19 provided in the guide member 17 toward the inner peripheral surface HF, and the guide member is formed. A / E conversion (not shown) that detects a change in the air pressure corresponding to a change in the gap C between the surface 17F of the work piece 17 and the inner peripheral surface HF of the processed hole H and converts the detected value into an electric signal. The inner diameter value of the processed hole H is calculated by converting the electric signal into an electric signal.

When honing is performed while measuring the inner diameter as described above, the inner diameter of the master ring MR having the reference hole MH having the same diameter as the target inner diameter value of the processed hole H is set as follows.
The measurement is performed by the air nozzle 19 described above, and the machining is continued until the inner diameter of the machining hole H is within the allowable dimension with respect to the inner diameter of the reference hole MH.

When honing the workpiece W as described above, the grindstone 3 of the honing head 1 is in a new state in order to make the grindstone 3 more familiar with the inner peripheral surface HF of the processing hole H. Then, the grindstone 3 is formed using the grindstone 5 shown in FIG. The grindstone 5 to be ground is made of metal and has a cylindrical inner surface 5H having substantially the same shape as the work W. On the cylindrical inner surface 5H,
A coating of boron nitride CBN is formed by electrodeposition.

When the grindstone 3 is formed, the honing head 1 is attached to the grindstone 5 fixed to the main body of a grindstone forming mechanism (not shown), and a supporting mechanism similar to that of the honing machine shown in FIG. And is rotated (in the direction of arrow A in FIG. 3) and axially (in the vertical direction in FIG. 1). At this time, in the honing head 1, the whetstone 3 is moved radially outward by the downward movement of the expanding taper portion 23 shown in FIG. Pressing with.

As a result, the tip end surface of the grindstone 3 is brought into sliding contact with the cylindrical inner surface 5H of the grindstone 5, and a forming operation for the grindstone 3, that is, an edging process for grinding and removing the corners of the grindstone 3 is performed. It will be. Since the hard boron nitride CBN is provided on the inner surface 5H of the cylinder, the grinding and removing work can be performed efficiently, and the grinding wheel 35 can have a long life. Here, the grindstone 5 to be ground has a cylindrical inner surface 5H having substantially the same shape as the inner peripheral surface HF of the processing hole H of the work W.
Therefore, the tip surface of the grindstone 3 whose corners are ground and removed becomes a convex curved surface that is familiar with the inner peripheral surface HF of the work W, and the honing process for the work W after the grindstone molding can be performed accurately. You can

FIG. 4 shows a state in which the grindstone 3 is finished to be formed by using the material 31 to be ground, which is the same material as the work W, after the grinding of the grindstone 3 by the grindstone 5 to be ground is completed.
It is a top view corresponding to. Like the grindstone 5 to be ground, the grinding material 31 is a cylindrical inner surface 31 having substantially the same shape as the work W.
If the workpiece W is equipped with H and the work W is, for example, a cast iron cylinder block of an engine, it is composed of a liner material made of cast iron.

When the grindstone 3 is formed and finished by using the material to be ground 31, the grindstone fixed to the main body of the grindstone forming mechanism (not shown) is ground in the same manner as the forming operation using the grindstone 5. The honing head 1 is rotated and vertically moved while pressing the grindstone 3 against the material 31 toward the cylindrical inner surface 31H in the radial outward direction. As a result, the convex curved surface of the tip of the grindstone 3 is brought into sliding contact with the cylindrical inner surface 31H of the workpiece 31, and the grinding finish of the grindstone 3 after the molding is completed. As a result, the tip of the grindstone 3 is finished. The surface is the inner peripheral surface H of the work W.
It becomes more familiar with F.

Further, since the grindstone 3 is formed and finished under the same conditions as when it is mounted on the honing head 1, that is, under the same conditions as when machining the workpiece W, there is a rattling in the circumferential direction during the forming and finishing operation. Does not occur, and the molding accuracy is improved.

In FIG. 5, the step of forming the grindstone 3 in FIG. 2 is step 1 (from the start of work 0 to time t ₁ ), and the step of forming the grindstone 3 in FIG. 4 is step 2 (from time t ₁ to t ₂ ).
Grinding wheel 5 of grinding wheel 3 or material 3 to be ground
It shows the change over time in the pressing pressure (expansion pressure P) on No. 1, and the expansion pressure P is set high in step 1 and low in step 2. As a result, the whetstone 3 is efficiently shaped and finished.

FIG. 6 relates to another embodiment of the present invention, in which the honing head 1 is molded on the grindstone 3 by a cylindrical base member 33 fixed to the main body of a grindstone molding mechanism (not shown). A pair of grindstones 35 for grinding and a pair of grindstones 37 for forming finish of the grindstone 3 after molding are respectively installed.

The pair of grindstones 35 to be ground are arranged so as to face each other and have a concave curved surface having substantially the same curvature as the inner peripheral surface HF of the work W to be machined by the honing head 1. , And is made of metal, and boron nitride CBN is provided on its inner peripheral surface by electrodeposition, as in the case of the grindstone 5 to be ground shown in FIG. On the other hand, the pair of materials to be ground 37 are also arranged so as to face each other, have a concave curved surface having substantially the same curvature as the inner peripheral surface HF of the work W, and form the other part in the circumferential direction of the cylindrical inner surface. The workpiece W is formed of the same material as the workpiece 31 shown in FIG.

The pair of grindstones 35 to be ground are the base member 33.
Is fixed to the concave curved surface of the tip of the first shoe 41 that is movable in the direction of arrow D in the first guide hole 39 formed in the first shoe 41. It is connected to one hydraulic cylinder 45. The two first hydraulic cylinders 45 are supplied with the hydraulic pressure from the first hydraulic pressure supply unit 47, so that the surface to be ground of the grindstone 35 to be ground is aligned with the opening of the first guide hole 39. The protruding position where the forming operation is performed and the retracted position where the grinding wheel 35 is inserted into the first guide hole 39 and the forming operation is not performed are moved. The first shoe 41, the first rod 43,
The first hydraulic cylinder 45 and the first hydraulic pressure supply unit 47 constitute a first drive mechanism for moving the grindstone 35 to be ground.

On the other hand, the pair of materials 37 to be ground are fixed to the concave curved surface of the tip of the second shoe 51 which is movable in the direction of arrow E in the second guide hole 49 formed in the base member 33. The second shoe 51 is connected to the second hydraulic cylinder 55 via the second rod 53. Two second
The hydraulic cylinder 55 is supplied with the hydraulic pressure from the second hydraulic pressure supply unit 57, so that the grinding and finishing operation of the grindstone 3 is performed by aligning the surface to be ground of the material to be ground 37 with the opening of the second guide hole 49. The protruding position to be performed and the material 37 to be ground are set in the second guide hole 4
9 and move it to a retracted position where the molding finishing operation is not performed. The second shoe 51, the second rod 53, the second hydraulic cylinder 55, and the second hydraulic pressure supply portion 57 constitute a second drive mechanism for moving the material to be ground 37.

In the structure shown in FIG. 6, when the grindstone 3 is formed by using the grindstone 35 to be ground while the honing head 1 is rotated and moved up and down while pressing the grindstone 3 in the radial outward direction. Is a retracted position where the grindstone 35 can be brought into contact with the grindstone 3 at the protruding position shown in FIG. 6 and the material to be ground 37 is inserted into the second guide hole 49 to separate from the tip surface of the grindstone 3. It is done in the state.

Here, six grindstones 3 are provided at equal intervals in the circumferential direction of the honing head 1. The six grindstones 3 are provided.
As shown in FIG. 3, the expansion taper portion 23 simultaneously expands radially outward, and the spring 15 simultaneously constantly urges radially inwardly. On the other hand, the two grindstones 35 to be ground which are located at positions opposite to each other.
Since each of them occupies an approximately ¼ area in the circumferential direction on the inner surface of the cylinder, at least one of the six grindstones 3 is always affected by the rotational position of the honing head 1 and is always ground. It means that the grindstone 35 is being pressed.

As a result, the grindstone (indicated by reference numeral 3 (P) in FIG. 6) at the position facing the material to be ground 37 in the state of FIG. 6 projects further forward from the state of FIG. When the honing head 1 reaches the grindstone 35 by the rotation of the honing head 1, the grindstone 3 (P) does not get caught on the peripheral edge of the opening of the second guide hole 49, and the honing head 1 rotates. The grindstone 3 is slidably contacted with the grindstone 35 to be ground without hindering the molding.

After the grindstone 3 is formed as described above, the grindstone 3 is formed and finished by using the material 37 to be ground. In this case, the grindstone 35 is set to the retracted position, By placing the work piece 37 in the protruding position similarly to the grind stone 35 at the time of forming the grindstone 3, the grindstone 3 slides into contact with the work piece 37 without disturbing the rotation of the honing head 1 and is formed. It will be finished.

Also in the case of FIG. 6 described above, since the inner peripheral surfaces of the grindstone 35 to be ground and the material 37 to be ground have substantially the same curvature as the inner peripheral surface HF of the work W, the grindstone 3 is formed by molding and finishing. The front end surface of the is a convex curved surface that is familiar with the inner peripheral surface HF of the work W, and honing can be performed on the work W after the grindstone is formed with high accuracy, as shown in FIGS. 1, 2 and 4. The same effect as the example is obtained. Further, in the example of FIG. 6, since the grinding wheel 35 and the grinding material 37 incorporated into one base member 33 can continuously perform the steps from forming the grinding wheel 3 to forming finishing, these operations can be performed in a short time. it can.

Incidentally, the grindstone 5 to be ground in the example of FIGS.
As and 35, alumina (Al ₂ O ₃ ) may be used instead of the structure in which boron nitride is electrodeposited on the surface of the metal.

[Brief description of drawings]

FIG. 1 is a front sectional view showing a grinding stone forming operation according to an embodiment of the present invention.

FIG. 2 is a plan sectional view of FIG.

FIG. 3 is a front sectional view showing a honing operation by a honing head provided with a grindstone.

FIG. 4 is a plan sectional view showing a molding finishing operation following the molding operation of FIGS. 1 and 2;

FIG. 5 is an explanatory diagram showing an expansion pressure of a grindstone during a grindstone forming operation and a grindstone forming / finishing operation.

FIG. 6 is a plan sectional view showing another embodiment of the present invention.

[Explanation of symbols]

 W Work HF Inner peripheral surface CBN Boron nitride 1 Honing head 3 Grinding stone 5 Grinding stone 5H, 31H Cylinder inner surface 31 Grinding material 41 First shoe (first driving mechanism) 43 First rod (first driving mechanism) ) 45 first hydraulic cylinder (first drive mechanism) 47 first hydraulic pressure supply section (first drive mechanism) 51 second shoe (second drive mechanism) 53 second rod (second drive) Mechanism) 55 second hydraulic cylinder (second drive mechanism) 57 second hydraulic supply unit (second drive mechanism)

Claims (6)

[Claims] 1. A new grindstone before use, which is provided on the outer peripheral portion of a honing head, is pressed against the inner surface of the grindstone having a cylindrical inner surface having substantially the same shape as the work to be machined by the honing head, The honing head is characterized in that the honing head and the grindstone are rotated relative to each other, and a sliding contact between the grindstone and the grindstone is performed to grind and remove a corner portion of the grindstone to form the grindstone. Grinding wheel forming method. 2. A honing head and the material to be ground are provided while pressing a new grindstone of a honing head against the cylindrical inner surface of a material to be ground having the same material as that of a work, the inner surface of the material being the same as that of the material to be ground. 2. The method of forming a grindstone for a honing head according to claim 1, wherein the grindstone is shaped and finished after the grindstone is formed by the grindstone by the relative rotation and sliding contact between the grindstone and the material to be ground. 3. A grindstone to be ground which is slidably in contact with a new grindstone before use provided on the outer peripheral portion of the honing head to grind and remove the corners of the grindstone to form the grindstone. A grindstone to be ground, characterized in that it has a cylindrical inner surface of substantially the same shape as the work to be machined, and the inner surface of the cylinder serves as a sliding contact surface with the grindstone. 4. The grindstone to be ground according to claim 3, wherein boron nitride is provided on a sliding contact surface of the honing head with the grindstone. 5. A honing head, which is provided with a grindstone on the outer periphery and is rotatable and axially movable, and the grindstone are in sliding contact in the circumferential direction, and the grindstone is formed by grinding and removing the corners of the grindstone. In a grindstone forming apparatus including a grindstone to be ground, the grindstone to be ground has a concave curved surface having substantially the same curvature as a cylindrical inner surface of a workpiece processed by a honing head to form a part in a circumferential direction on the cylindrical inner surface. In addition, the first drive mechanism is movable between a protruding position where it can contact the tip surface of the grindstone of the honing head and a retracted position where it separates from the tip surface, and the grindstone is a cylindrical inner surface. Is provided with a workpiece to be ground of the same material as the workpiece, and the workpiece has a concave curved surface having substantially the same curvature as the inner surface of the cylinder of the workpiece, and By the drive mechanism,
A honing head grindstone forming device, which is movable between a protruding position capable of contacting the tip surface of the grindstone of the honing head and a retracted position away from the tip surface. 6. The honing head grindstone forming apparatus according to claim 5, wherein boron nitride is provided on a sliding contact surface of the grindstone to be ground with the grindstone of the honing head.