JPH0639711A - Grinder - Google Patents

Abstract

PURPOSE:To provide a grinder suitable for processing a piece of work excellently in flatness and accurately at an item. CONSTITUTION:A dressing grinding wheel 9 is arranged at a position linearly symmetrical with work W to the axis core of a cup type grinding wheel 2, and also is provided so that the end surface of the dressing grinding wheel 9 can abut on part of the tip surface of the cup type grinding wheel 2. In grinding work with the cup type grinding wheel 2, not only part of the end surface of the work W but concurrently also part of the end surface of the dressing grinding wheel 9 abut on the tip surface of the cup type grinding wheel 2, and also when the cup type grinding wheel 2 is tilted more at the time of grinding than before the grinding by comparing, the abutting ford of the dressing grinding wheel 9 is adjusted with a pushedly pressing rod 13 to correct the tilt of the cup type grinding wheel 2 to a condition before grinding for surely preventing the tilt of the grinding wheel axis of the cup grinding wheel 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grinder that grinds an end surface of a work piece with a tip end surface of a cup-shaped grindstone, and more particularly, enables the work piece to be finished as a single piece with high flatness and high accuracy. It is a thing.

[0002]

2. Description of the Related Art Conventionally, FIG.
What is shown in (a) or (b) is known.

That is, in the grinding machine shown in FIG. 1 (a), during grinding, the cup-shaped grindstone 2 and the circular cross-section workpiece W are rotated around their respective axial centers O ₁ and O _2, and at the same time, the workpiece is rotated. A part of the end surface of the workpiece W and a part of the tip surface of the cup-shaped grindstone 2 are brought into contact with each other while the center of rotation of W, that is, the axis O ₂ is substantially aligned with the outer circumference of the cup-shaped grindstone 2. Is configured.

On the other hand, in the grinding machine shown in FIG. 1 (b), at the time of grinding, the two workpieces W, W each having a circular cross section are arranged laterally in a row, and each of them is rotated about its respective axis O ₂ , O ₂ . While rotating, the cup-shaped grindstone 2 is rotated around its axis O ₁ . In this manner, the two workpieces W, W and the cup-shaped grindstone 2 are rotated, and the tip surfaces of the cup-shaped grindstone 2 are brought into contact with the end surfaces of the workpieces W, W at the same time.

[0005]

However, as shown in FIG.
In the conventional grinding machine as shown in (a), since only a part of the tip surface of the cup-shaped grindstone 2 is brought into contact with a part of the end surface of the workpiece W having a circular cross section during grinding. Since the load due to the grinding is generated only on the side where the cup-shaped grindstone 2 and the workpiece W contact _each other, that is, on one side with respect to the axis O ₁ of the cup-shaped grindstone 2, the grindstone axis of the cup-shaped grindstone 2 is prevented from tilting. As a result, the workpiece cannot be ground with good flatness and high precision.

Further, in the conventional grinder shown in FIG. 4 (b), the tip surface of the cup-shaped grindstone 2 is brought into contact with the end surfaces of the two workpieces W, W each having a circular cross section at the same time during grinding. Load is evenly generated on both sides with respect to the axis O ₁ of the cup-shaped grindstone, and the grindstone axis of the cup-shaped grindstone 2 can be prevented from tilting as described above. Therefore, when finishing two workpieces with high flatness and high accuracy. Although suitable, two workpieces must be ground at the same time in order to finish with high flatness and high precision in this way, and one workpiece cannot be machined with high flatness and high precision as a single piece.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a grinder suitable for processing one work piece with good flatness and high accuracy as a single piece. .

[0008]

In order to achieve the above object, the present invention holds a grinding wheel mounted on the tip surface of a grinding wheel shaft and a work piece located on the grinding surface side of the grinding wheel. While rotating while rotating, a workpiece rotating mechanism that brings a part of the workpiece into contact with a part of the grinding surface of the grinding wheel, and a position that is line-symmetric with the workpiece with respect to the axis of the grinding wheel. And a dressing grindstone that is always in contact with a part of the grinding surface of the grinding grindstone, and when the grinding grindstone is tilted during grinding as compared to before grinding, the dressing grindstone contact Inclination adjusting means for adjusting the contact force to adjust the inclination of the grinding wheel to the state before grinding.

[0009]

According to the present invention, when a workpiece is ground by a grinding wheel, not only a part of the workpiece but also a part of the dressing wheel are simultaneously brought into contact with the grinding surface of the grinding wheel. When the grindstone for grinding is tilted more during grinding than before grinding, the tilt correction means adjusts the contact force of the dressing grindstone to correct the tilt of the grindstone to the state before grinding.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a grinding machine according to the present invention will be described in detail below with reference to FIGS.

This grinder has a grindstone shaft unit 1 as shown in FIG. 1, and a grindstone shaft (not shown) is rotatably supported by a bearing or the like in the grindstone shaft unit 1, and the tip of the grindstone shaft is rotatably supported. A cup-shaped grindstone 2 for grinding is attached to the surface, and this cup-shaped grindstone 2 is arranged on the same axis O _{1 as the} grindstone shaft. The rear end of the grindstone shaft is connected to the motor via a pulley, a belt or the like (not shown).

Further, a workpiece rotating mechanism 3 is provided on the tip side of the cup-shaped grindstone 2 as described above, and this workpiece rotating mechanism 3 is used when grinding with the cup-shaped grindstone 2. Workpiece W with a circular cross section located on the tip side of the
While rotating the workpiece W while it is being rotated about its axis O ₂ and the rotation center of the workpiece W, that is, the axis O ₂ is substantially aligned with the outer periphery of the cup-shaped grindstone 2, a part of the end surface of the workpiece W is held. Is abutted on a part of the tip surface of the cup-shaped grindstone 2.

By the way, a movable holder 5 which is arranged independently of the grindstone shaft unit 1 and the workpiece rotating mechanism 3 is arranged on the tip side of the cup-shaped grindstone 2, and the movable holder 5 is also arranged. Is the cup-shaped grindstone 2 through the guide bars 6 and 6.
It is installed so that it can slide up and down toward the tip side of.

A grindstone shaft unit 7 is built in the movable holder 5, and a grindstone shaft 8 in the grindstone shaft unit 7 is rotatably supported by a bearing (not shown) or the like. The cup-shaped grindstone 2 is installed in a state of being offset parallel to the grindstone axis to which the cup-shaped grindstone 2 is attached.

Further, a dressing grindstone 9 having a circular cross section is attached to the tip end surface of the grindstone shaft 8, and such dressing grindstone 9 has the workpiece W with respect to the axis of the cup-shaped grindstone 2. Is provided at a position symmetrical with respect to and the end surface thereof is always in contact with a part of the tip surface of the cup-shaped grindstone 2.

On the other hand, a pulley 1 is provided at the rear end of the grindstone shaft 8.
A motor 12 is connected via 0, 10 and a belt 11, and a pressing lot 13 is provided as an inclination correcting means for the cup-shaped grindstone 2. One end of the pressing lot 13 is the grinding stone shaft unit 7. It abuts on the rear end surface and the other end is fixed to the tip of a piston provided in the hydraulic cylinder 14.

The cup-shaped grindstone 2 is constructed so that it can be lowered toward the workpiece W at a predetermined speed via a notch feed device (not shown).

Next, an electric circuit configuration essential for this grinder will be described with reference to FIG.

This grinder has a sensor 15 such as a laser length measuring machine or a non-contact displacement gauge on the rear end face side of the cup-shaped grindstone 2 as shown in FIG.
The distance is measured and is positioned and fixed to a fixed frame or the like that supports the grindstone shaft unit 1 (see FIG. 1). The sensor 15 can detect the change in displacement remarkably when it is installed on the outermost part of the rear end surface of the cup-shaped grindstone 2.

Further, the detection value from the sensor 15 is always output to the NC device 17 via the distance detection circuit 16, and the NC device 17 is provided with
A grindstone inclination amount data table 18 is provided, and the grindstone inclination amount data table 18 records the grindstone inclination amount corresponding to the detection value output from the sensor 15 (the distance between the sensor 15 and the cup-shaped grindstone 2). There is.

Further, in the NC device 17 as described above,
Before and during grinding, the grindstone tilt amounts before and during grinding are determined from the grindstone tilt amount data table 18 based on the detection value (distance between the sensor 15 and the cup-shaped grindstone 2) output from the sensor 15. , Internal memory 19
, A function of subtracting the grindstone tilt amount before grinding from the grindstone tilt amount during grinding written in the internal memory 19, and a result of the subtraction larger than the grindstone tilt allowable amount A, that is, before grinding. When the cup-shaped grindstone 2 is tilted during grinding, the pressure control valve 20 is provided with an instruction function for instructing to increase the pressing force of the pressing lot 13.

Next, the operation of the grinding machine configured as described above will be described with reference to FIGS.

According to this grinder, at the time of grinding, as shown in FIG. 1, the cup-shaped grindstone 2, the workpiece W and the dressing grindstone 9 are rotated about their respective axial centers O ₁ , O ₂ and O ₃ , respectively. In the state where the center of rotation of the workpiece W, that is, the axis O ₂ and the outer periphery of the cup-shaped grindstone 2 are substantially aligned with each other, the tip surface of the cup-shaped grindstone 2 is not only a part of the end surface of the workpiece W, At the same time, a part of the end surface of the dressing grindstone 9 also abuts.

Further, the dressing grindstone 9 as described above
The contact force of is adjusted according to the process shown in FIG.

That is, according to FIG. 2, in grinding the end surface of the workpiece W, the grindstone inclination allowable amount A and the unit setting pressure value B for correction which are allowed during grinding are shown in FIG. Write to the internal memory 19 of the NC device 17, respectively. On the other hand, an initial low hydraulic pressure is supplied to the hydraulic cylinder 14 via the pressure control valve 20. In this way, in the hydraulic cylinder 14 to which the initial low hydraulic pressure is supplied, the pressing lot 13
Presses the rear end surface of the grindstone shaft unit 7, and as a result, the movable holder 5 slides toward the cup-shaped grindstone 2 side along the guide bar 6, and the end surface of the dressing grindstone 9 becomes the end surface of the cup-shaped grindstone 2. The part is contacted with an initial low hydraulic pressure (step 100).

Before starting the grinding with the cup-shaped grindstone 2, the grindstone inclination amount data table is based on the detection value (the distance between the sensor 15 and the cup-shaped grindstone 2) output from the sensor 15 by the NC device 17. The grindstone inclination amount C before grinding is calculated from 18, and after the grindstone inclination amount C is written in the internal memory 18 (step 102), grinding by the cup-shaped grindstone 2 is started (step 104).

Thereafter, in the NC device 17, the cup-shaped grindstone 2
It is determined whether or not the grinding is currently being performed from the grinding load and the like that occur in step S106. If it is determined that grinding is being performed (Yes), the grinding wheel inclination amount data table 18 indicates that grinding is in progress based on the detection value (the distance between the sensor 15 and the cup-shaped grinding wheel 2) output from the sensor 15. The grindstone inclination amount D is obtained and written in the internal memory 19 (step 108).

Next, the NC device 17 subtracts the grindstone inclination amount C before grinding from the grindstone inclination amount D during grinding written in the internal memory 19 as described above (step 110). Here, when the subtraction result is larger than the grindstone inclination allowable amount A, that is, when the cup-shaped grindstone 2 is tilted more during grinding than before grinding (No), the above unit is set for the pressure control valve 20. It is instructed to increase the pressing force of the pressing lot 13 by the set pressure value B, and the process returns to step 106. (Step 112).

In this way, steps 106 to 1
When the process of 12 is repeated, the pressing force of the pressing lot 13, that is, the contact force of the dressing grindstone 9 is adjusted in the increasing direction.

Further, in the adjustment process as described above, when the subtraction result in step 110 is 0, that is, when the inclination of the cup-shaped grindstone 2 during grinding is corrected to be equal to that before grinding. (Yes) returns to the process of step 106 without giving an instruction to increase the hydraulic pressure to the pressure control valve 20, that is, grinding is performed with the inclination of the cup-shaped grindstone 2 during grinding being equal to that before grinding. Continued.

That is, in this grinding machine, when the cup-shaped grindstone 2 is tilted more during grinding than before grinding, the steps 106 to 112 are repeated to adjust the contact force of the dressing grindstone 9. Then, the inclination of the cup-shaped grindstone 2 is corrected to the state before grinding.

Therefore, according to the grinding machine of the above-described embodiment, when the workpiece is ground by the cup-shaped grindstone, not only a part of the end surface of the workpiece but also the dressing is simultaneously performed on the tip surface of the cup-shaped grindstone. If a part of the end surface of the grinding wheel is also in contact, and the grinding wheel is tilted more during grinding than before grinding, adjust the contact force of the dressing wheel to adjust the inclination of the cup-shaped grindstone before grinding. In order to correct the condition, the load acting on the cup-shaped grindstone is always evenly distributed on both sides of the workpiece and the dressing grindstone in a well-balanced manner, and it is possible to surely prevent the grindstone shaft of the cup-shaped grindstone from tilting. It can be processed as a single item with higher flatness and high accuracy.

Further, in this grinder, the dressing grindstone not only balances the load as described above, but also dresses the tip surface of the cup-shaped grindstone, that is, the grinding work surface, so that the sharpness of the cup-shaped grindstone is improved. It is always excellent and can perform stable grinding for a long period of time.

In the above embodiment, when grinding the workpiece, the cup-shaped grindstone is lowered toward the workpiece, but instead of this, the workpiece is moved up toward the cup-shaped grindstone. Of course, it is okay to do so.

Although the cup-shaped grindstone is used as the grinding grindstone in the above embodiment, it is not limited to this.
As the grindstone for grinding, it is possible to apply a grindstone such as a strate cup type, a taper cup type, a dish type, an offset type, a nut type ring type, and a nut type disc type.

[0036]

In the grinding machine according to the present invention, when the workpiece is ground by the cup-shaped grindstone as described above, the tip surface of the cup-shaped grindstone is not limited to a part of the end surface of the workpiece at the same time. If part of the end surface of the dressing wheel is also in contact and the grinding wheel is tilted during grinding compared to before grinding, adjust the contact force of the dressing wheel to adjust the inclination of the cup-shaped grindstone before grinding. In order to correct the condition, the load that acts on the cup-shaped grindstone is always evenly balanced on both sides of the workpiece and dressing grindstone, and it is possible to reliably prevent the grindstone shaft of the cup-shaped grindstone from tilting. It is possible to process a single product with higher flatness and high accuracy.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view showing a main part of a grinding machine according to the present invention.

FIG. 2 is a block diagram illustrating an electric configuration essential to the grinder shown in FIG.

FIG. 3 is a flowchart illustrating the operation of the grinder shown in FIG.

FIG. 4 is an explanatory diagram illustrating a conventional grinding machine.

[Explanation of symbols]

 2 Cup type grindstone for grinding 3 Workpiece rotating mechanism 9 Grinding stone for dressing W Workpiece

Claims (1)

[Claims] 1. A grinding grindstone attached to a tip end surface of a grindstone shaft and a workpiece positioned on the grinding surface side of the grinding grindstone while being rotated while holding a part of the workpiece for the grinding. A workpiece rotating mechanism that comes into contact with a part of the grinding surface of the grindstone, and is provided in a position symmetrical to the workpiece with respect to the axis of the grinding wheel, and on a part of the grinding surface of the grinding wheel. When the whetstone for dressing that constantly contacts and the grindstone for grinding are more inclined during grinding than before grinding, the contact force of the grindstone for dressing is adjusted to the state before grinding by adjusting the contact force of the grindstone for grinding. A grinding machine, comprising: a tilt correcting means for correcting.