JP2589681Y2 - Wheel tool for plateau surface processing - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grinding wheel tool for forming a plateau surface for forming a plateau surface to be provided on a sliding portion of a hole of a machine component for the purpose of preventing seizure.

[0002]

2. Description of the Related Art For the purpose of preventing seizure of a sliding portion of a hole in a machine part, for example, a plateau surface having a high oil film holding ability is machined on an inner surface of an engine cylinder or the like.

Conventionally, as a technique for processing such a plateau surface, as a general method, two steps of performing rough honing and then finishing honing are performed.
They used three processes of medium honing and finish honing. In some cases, a honing machine dedicated to plateau processing is used in which a rough whetstone and a finishing whetstone are placed in one honing mandrel and mechanically used.

[0004]

As described above, in the conventional plateau surface processing method, the honing is generally performed in two to two times.
It was necessary to process in multiple steps, such as three steps. When a honing machine dedicated to plateau processing is used, the structure is complicated and the apparatus becomes expensive. Furthermore, the honing machine dedicated to plateau processing is used for large diameter machines such as engine cylinders,
For smaller diameters, mandrel fabrication was technically difficult and impossible.

SUMMARY OF THE INVENTION An object of the present invention is to provide a grinding wheel tool for plateau surface machining that has a simple structure and can process the plateau surface in one step at a low cost, and can also process small-diameter objects.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a grindstone shaft, a grindstone head which is swingably mounted around a support shaft whose axis is orthogonal to the grindstone shaft, and a grindstone head. And a whetstone provided on the side surface of the whetstone, and the whetstone is configured to include a rough whetstone and a finishing whetstone separately arranged in the axial direction of the whetstone shaft.

[0007]

[Function] With the grindstone head facing the inner diameter of the work, for example, when the oscillation is performed along the axial direction while rotating the grindstone shaft, the grindstone head that has brought the grindstone surface into contact with the inner diameter surface of the work is attached to the grindstone shaft. On the other hand, it oscillates around a spindle that is orthogonal to the
Depending on the direction of oscillation, the moment around the spindle acting on the wheel head is reversed. Thereby, the magnitude relationship of the processing pressure applied to the rough grinding wheel and the finishing grinding wheel provided separately in the axial direction of the grinding wheel shaft on the side surface of the grinding wheel table is alternately reversed,
That is, the rough grinding and the finish grinding are alternately repeated to form a plateau surface on the inner diameter surface of the work.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a grinding wheel tool for machining a plateau surface according to the present invention; FIG. 1 and 2 showing the configuration of a platen surface processing grindstone tool 10 as an example to which the present invention is applied, 11 is a housing forming a jig body, 21 is a grindstone shaft holder, 31 is a grindstone shaft, and 41 is a grindstone stand. , 51 are pressure weights, 61 is a counter, 71 is a support shaft, and 81 is a pressure weight arm.

A housing 11, which is a jig body, is formed of a cylindrical member, and one end of the housing 11 is fitted to the male tapered portion 2 of a rotary spindle 1 of a drilling machine, which is one of machine tools (not shown). The female tapered portion 12 is provided, and the other end is provided with bifurcated support pieces 13. A grindstone shaft holder 21 is incorporated in the housing 11. The grindstone holder 21 is formed of a shaft-like member having an outer shape smaller than the inner diameter of the housing 11, and has a small-diameter portion 22 at one end and a large-diameter portion 23 at the other end. A grindstone shaft 31 is incorporated in the large-diameter portion 23 of the grindstone shaft holder 21 and fixed by a set screw 24 from the direction crossing the axis.

The grindstone shaft 31 has a slit 32 formed at the tip thereof, and a grindstone table 41 is assembled in the slit 32 so as to be able to swing around a spindle 33 (see FIG. 4) using a spring pin. As shown in FIG. 4, the grindstone 41 has a finishing grindstone 42 and a rough grindstone 43 on one side thereof which are vertically separated so as to be symmetrical with respect to the rotation center (support shaft 33) of the grindstone 41. To be prepared. These two types of grindstones 42 and 43 are made of, for example, CBN or diamond.

A pressure weight 51 and a counter 61 provided opposite to the pressure weight 51 are provided on the outer periphery of the housing 11.
Has been assembled. As shown in FIG.
The counter 61 is mounted so as to coincide with a portion smaller than a half of the outer circumference of the housing 11, and the counter 61 is fitted and mounted on a portion exceeding a half of the outer circumference of the housing 11. The grindstone shaft holder 21 is pivotally connected to the bifurcated support pieces 13 of the housing 11 by a support shaft 71 in the direction crossing the axis so as to be swingably connected. Further, a pressure weight arm 81 that supports the pressure weight 51 through the housing 11 in the diametric direction is attached to the small diameter portion 22 of the whetstone shaft holder 21.

That is, as shown in FIG.
Has a shape corresponding to a portion less than half of the outer circumference of the housing 11, and has a pressure weight arm 81 from its diametric direction.
The small-diameter portion 22 of the grindstone shaft holder 21 is fitted to the tip of a pressure weight arm 81 holding the outer peripheral surface of the pressure weight 51 by the large-diameter head 82. And fixed with mounting bolts 83.
The counter 61 faces the pressure weight 51 and fits over a part of the outer periphery of the housing 11 and is fixed by two diametrically opposed mounting bolts 62.

As shown in FIGS. 1 and 2, the large-diameter portion 23 of the grindstone shaft holder 21 faces between the forked support pieces 13 of the housing 11, and supports the shaft in the direction crossing the axis. A large-diameter head 72 at one end of the support shaft 71 is applied to the outer surface of one support piece 13, and a C-shaped retaining ring 73 is fitted to the other end projecting from the outer surface of the other support piece 13. ing. Thus, with respect to the housing 11 mounted on the rotating main shaft 1, the support shaft 71 orthogonal to the axis of the rotating main shaft 1 is provided.
A grindstone shaft 31 is assembled so as to be swingable therearound.

Here, the support shaft 71 and the support shaft 33 for assembling the grindstone table 41 in the slit 32 of the grindstone shaft 31 in a swingable manner have axes parallel to each other. In addition, the pressure weight arm 81 is disposed so that the axis thereof is different from the support shaft 71 in the direction perpendicular to the axis, and the pressure weight 51 and the grinding wheels 42 and 43 are disposed diametrically opposite to each other. ing.

Further, a floating adjusting screw 25 for adjusting the swing amount of the grinding wheel shaft holder 21 is provided on the housing 11.
Has been assembled. That is, in order to adjust the floating amount of the grindstone shaft 31 around the support shaft 71 with respect to the housing 11, the floating adjustment screw 25 which comes into contact with the outer diameter of the grindstone shaft holder 21 at the position facing the grindstones 42 and 43 is mounted on the housing 11. And the lock screw 26 is further screwed in.

At the time of machining, the adjusting screw 25 is adjusted so that the tip of the grindstone shaft 31 hits the end face of the work W,
The grindstones 42 and 43 of the grindstone table 41 should not be too far from the inner surface of the hole H of the work W,
After setting the surfaces 2 and 43 to interfere with the inner surface of the hole H of the work W, the lock screw 26 is tightened. Since the whetstones 42 and 43 are worn, it is necessary to periodically adjust the floating amount in this way.

Next, plateau surface processing using the plateau surface processing grindstone tool 10 having the above-described configuration will be described.
A description will be given of a case in which a work W having a hole H used for fitting with a sliding member is machined. First, prior to machining, a housing 1 is mounted on a male tapered portion 2 of a rotating spindle 1 of a drilling machine (not shown).
One female taper portion 12 is fitted.

When the rotary main shaft 1 is driven to rotate, a centrifugal force is generated in the pressure weight 51 provided on the outer periphery of the housing 11, and the grindstone shaft holder 21 connected to the pressure weight 51 via the pressure weight arm 81 supports the support shaft 71. Rocks as Accordingly, the grindstone shaft 31 connected to the grindstone shaft holder 21 also swings, and the grindstones 42 and 43 provided on one side surface of the grindstone table 41 abut on the inner surface of the hole H of the work W. The contact pressure of the whetstones 42 and 43 against the inner surface of the hole H of the work W is the pressure
Is determined by the centrifugal force of Then, by applying oscillation in the vertical direction, the moment generated around the spindle 33 on the grindstone table 41 is reversed, and the rough grinding and the finish grinding are alternately performed by the finishing grindstone 42 and the rough grindstone 43, and the work is performed. A plateau surface is formed on the inner surface of the hole H of W.

FIG. 5 explains the working principle. In the state where the oscillation direction is downward, as shown in FIG. occurs, than working pressure f ₁ of grindstone 42 finishing the illustrated upper becomes large processing pressure f ₂ shown below the rough grindstone 43, therefore, rough grinding by the Arato stone 43 is mainly performed. In addition, when the oscillation direction is upward, as shown in FIG. 5B, a clockwise clockwise moment about the spindle 33 is generated in the grindstone table 41, and the processing pressure of the rough grindstone 43 on the lower side in FIG. Finishing whetstone 4 above f _{2 in the} figure
2, the processing pressure f ₁ is increased, and therefore the finish grinding by the finishing whetstone 42 is mainly performed. In this way, the plateau surface can be formed on the inner surface of the hole H of the work W by alternately performing the rough grinding and the finish grinding.

As described above, the grinding wheel tool 10 for plateau surface machining according to the present invention is capable of grinding by rotation and oscillation using centrifugal force as a machining pressure. Are listed. The work W is made of SCM (chromium molybdenum steel), the diameter of the hole H is 8 mm, and is small.
A finishing CBN grinding wheel No. 42 and a roughing CBN grinding wheel No. 200 were used. As a result, a plateau surface like the surface roughness profile shown in FIG. 6 could be formed.

In the above embodiment, the working pressure is obtained by centrifugal force. However, the present invention is not limited to this, and it is also possible to use pneumatic pressure, hydraulic pressure or spring force. Good. Further, the tool may be fixed and the workpiece may be rotated. Further, for example, the position of the weight in the case of the centrifugal force method may be set between the support shaft position of the grinding wheel shaft with respect to the jig main body and the grinding wheel head position.

Then, the type of the workpiece to be subjected to the plateau surface processing, the mesh (grain size) of the grindstone, and further, for example, the vertical positional relationship between the rough grindstone and the finishing grindstone is reversed.
Needless to say, the specific detailed structure can be appropriately changed.

[0023]

[Effect of the Invention] As described above, according to the grinding wheel tool for plateau surface processing according to the present invention, the grinding wheel shaft is attached to the side surface of the grinding wheel base which is swingably mounted around a support shaft whose axis is orthogonal to the grinding wheel shaft. Since the rough grinding wheel and the finishing grinding wheel are provided separately in the axial direction, for example, by performing an oscillation operation along the axial direction while rotating the grinding wheel shaft,
By the reversal of the moment about the spindle acting on the grindstone table, the magnitude relationship of the processing pressure applied to the rough grinding wheel and the finishing grindstone is reversed alternately, and the rough grinding and finish grinding are alternately repeated, and the plateau surface Can be formed.

As described above, the plateau surface processing can be performed in one step at a low cost with a simple configuration in which the rough grinding wheel and the finishing grinding wheel are provided on one grinding wheel base, and the simple grinding wheel base is used. Therefore, plateau surface processing for small-diameter objects can be realized.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional front view showing a configuration of a platen surface processing grindstone tool as an example to which the present invention is applied.

FIG. 2 is a side view as viewed from a grinding wheel surface side in FIG. 1;

FIG. 3 is a sectional view taken along line AA of FIG. 1;

FIG. 4 is an enlarged view of a portion of the grinding wheel of FIG. 1;

FIG. 5 illustrates the processing principle according to the present invention.
(A) is an explanatory view of a state where the oscillation direction is downward,
(B) is an explanatory view of a state where the oscillation direction is upward.

FIG. 6 is a diagram showing a processing example of a plateau surface according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Spindle 10 Grinding wheel tool for plateau surface processing 11 Jig body (housing) 12 Female taper part 21 Grinding stone shaft holder 25 Floating adjustment screw 31 Grinding stone shaft 33 Support shaft 41 Grinding stone table 42 Finishing grinding stone 43 Rough grinding stone 51 Pressure weight 61 Counter 62 Mounting bolt 71 Support shaft 81 Pressure weight arm 83 Mounting bolt

Claims (1)

(57) [Scope of request for utility model registration] 1. A grindstone shaft, a grindstone table which is swingably mounted around a spindle whose axis is orthogonal to the grindstone shaft, and a grindstone provided on a side surface of the grindstone table. A grinding wheel tool for plateau surface processing, comprising a rough grinding wheel and a finishing grinding wheel which are arranged separately in an axial direction of a grinding wheel shaft.