JPS6377663A - Grinding stone and grinding method - Google Patents

Abstract

PURPOSE:To eliminate the exchanging work of a grindstone and improve grinding accuracy by providing the first and second grindstone plates having rough grinding abrasive grains and finish grinding abrasive grains respectively in parallel on the circumference so that abrasive grains are arranged continuously. CONSTITUTION:Taper faces 48, 56 inclined toward a rotary shaft 34 are formed on the side peripheries of the first and second disk-shaped grindstone plates 43, 44 respectively, and rough grinding abrasive grains 50 and finish grinding abrasive grains 58 are continuously arranged and fixed on the taper face 48 and the taper face 56 respectively. The center hole section 46 of the first grindstone plate 43 is coupled with the boss section 52 of the second grindstone plate 44 pivotally supported by the rotary shaft, and both grindstone plates 43, 44 are fixed by bolts 60. Accordingly, the material to be ground is roughly ground then finish-ground in sequence, thus exchanging of the grindstone is not required, the trouble for the exchange work is omitted, the displacement with the material to be ground is eliminated, and grinding accuracy can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a grinding wheel and a grinding method, and more particularly, in a cylindrical grinder, a first grinding wheel plate having rough grinding abrasive grains and a second grinding wheel plate having finish grinding abrasive grains are used. Using a grinding wheel arranged in parallel with a grinding wheel plate, the grinding operation using the first grinding wheel plate is followed by the grinding operation using the second grinding wheel plate, thereby reducing the number of work steps and achieving a highly accurate ground surface. The present invention relates to a grinding wheel that can be obtained and a grinding method using the same.

A cylindrical grinder is a grinder that mainly grinds the outer peripheral surface of a cylindrical workpiece. This cylindrical grinder has a movable table that moves in any direction, and a wheel-shaped grindstone that is rotationally driven by a drive source is attached to this movable table. Then, the outer peripheral surface of the cylindrical workpiece is ground by the rotationally driven grinding wheel.

By the way, some workpieces that are ground by a cylindrical grinder require extremely high grinding accuracy, such as engine valves for automobiles. In this case, in the conventional grinding method, first, a cylindrical grinder is equipped with a grinding wheel having rough grinding abrasive grains to carry out rough machining, and then the grinding wheel is ground. Finishing work is being carried out after replacing the grinding wheel with a grinding wheel.

However, in such a grinding method, the grinding wheel for rough grinding and the grinding wheel for finishing grinding must be replaced, and therefore, the replacement (Q) operation takes a considerable amount of time and reduces the production time of the product. It has been pointed out that there is a drawback that the grinding process is delayed.Also, a preparation stand, etc. for preparing a replacement grinding wheel is required near the cylindrical grinder, which results in waste of equipment or space. Furthermore, when replacing the grinding wheel, it is necessary to temporarily separate the grinding wheel from the workpiece for the replacement work, so the working position of the grinding wheel during rough grinding and the working position of the grinding wheel during finish grinding are different. There is a problem that a positional shift easily occurs between the grinding surface and the grinding surface, making it impossible to obtain a highly accurate ground surface.

The present invention has been made in order to overcome the above-mentioned disadvantages, and includes a first grindstone plate having rough grinding abrasive grains and a second grindstone plate having finish grinding abrasive grains that are arranged side by side and integrated. It is an object of the present invention to provide a grinding wheel and a grinding method that can reduce the number of work steps and obtain a highly accurate ground surface in a short time by continuously grinding a workpiece using a grinding wheel that is configured as follows. purpose.

In order to achieve the above object, the present invention provides a first grindstone plate having rough grinding abrasive grains on the circumference and a second grindstone plate having finish grinding abrasive grains on the circumference in parallel. The present invention is characterized in that the rough grinding abrasive grains and the finish grinding abrasive grains are arranged continuously.

In addition, the method of the present invention includes a first grinder having rough grinding abrasive grains on the circumference.
A method for grinding a workpiece using a grinding wheel in which a grindstone plate and a second grindstone plate having abrasive grains for finish grinding are arranged side by side, the first grindstone plate being directed toward the surface to be ground of the workpiece. The method is characterized in that rough grinding is performed by displacing the grinding wheel, and then finish grinding is performed by oscillating the second grindstone plate along the surface to be ground.

Next, the grinding wheel and the grinding method according to the present invention will be described in detail below with reference to the accompanying drawings, citing preferred embodiments in relation to an apparatus for carrying out the grinding wheel and method.

In FIG. 1, reference numeral 10 indicates a main body of a cylindrical grinder to which the grinding method using a grinding wheel according to the present invention is applied, and this main body 10 has a bed 12 fixed to a predetermined location.
, a first movable table 14 placed on the bed 12 and movable in the direction of arrow X, and the first movable table 1
In this case, the first moving table 14 is driven by a ball screw 20 that is rotationally driven by a servo motor 18 fixed to the bed 12. Move in the direction of arrow X. Further, the second moving table 16 is connected to the first moving table 14.
It moves in the direction of arrow Y by a ball screw 24 that is rotationally driven by a servo motor 22 fixed to the servo motor 22 .

A drive motor 26 is fixed to the second moving table 16, and a pulley 30 is attached to a drive shaft 28 of the drive motor 26. Further, a bearing portion 32 is fixed to the second movable table 16, and a rotating shaft 34 is rotatably supported by this bearing portion 32. In this case, a pulley 36 is attached to a rotating shaft 34 that protrudes from one end of the bearing 32, and a belt 38 is provided between this pulley 36 and the pulley 30 that is attached to a drive shaft 28 of a drive motor 26. is strung up. On the other hand, a substantially disc-shaped grinding wheel 40 having a tapered side circumferential surface is rotatably attached to a rotating shaft 34 that protrudes from the other end of the bearing portion 32 .

Here, the grinding wheel 40 is used to grind the face surface 41 of the umbrella portion 42a constituting the engine valve 42, and is constructed as shown in FIG. 2. That is, the grinding wheel 40 has a first grinding wheel plate 43 for rough grinding the face surface 41 of the engine valve 42, and a second grinding wheel plate 44 for finishing grinding the face surface 41. First whetstone plate 4
3 has a hole 46 formed in its center to which the rotating shaft 34 engages, and its side circumferential surface forms a tapered surface 48 that is inclined toward the rotating shaft 34. In this case, a single layer of rough grinding abrasive grains 50 made of CBN abrasive grains with a large grain size is fixed to the tapered surface 48 by electrodeposition or the like. On the other hand, the second whetstone plate 44 has a boss 52 at its center that fits into the hole 46 of the first whetstone plate 43.
A tapered hole 54 into which the rotating shaft 34 engages is formed in the center of the boss 52. Further, the side peripheral surface of the second grindstone plate 44 is a tapered surface 56 that is inclined toward the rotating shaft 34, and this tapered surface 56 has a single layer of CBN abrasive grains smaller in particle size than the rough grinding abrasive grains 50. Finish grinding abrasive grains 58 made of are fixed by electrodeposition or the like. The first and second grindstone plates 43 and 44 are integrally connected to each other by bolts 60 with the bosses 52 fitted into the holes 46.

Note that the diameter of the joint surface 62 of the first whetstone plate 43 is smaller than the diameter of the joint surface 64 of the second whetstone plate 44 that comes into contact with the joint surface 62, so that the tapered surface 48 of the first whetstone plate 43 and the second A step portion 66 is formed between the grindstone plate 44 and the tapered surface 56 . Here, the stepped portion 66 is set according to the difference between the grain size of the rough grinding abrasive grains 50 and the grain size of the finish grinding abrasive grains 58, and is formed between the grinding surface of the first whetstone plate 43 and the second whetstone plate 44. The grinding surface is substantially continuous.

The cylindrical grinder to which the grinding wheel and grinding method according to the present invention are applied is basically constructed as described above, and its operation and effects will be explained next.

First, the stem portion 42bt of the engine valve 42 is rotatably supported by the workpiece holding device 68. In this case, as the workpiece holding device 68, the Utility Model No. 60-9
It is preferable to use the technical idea disclosed in No. 7213. Next, the workpiece rotation means 70 is brought into contact with the umbrella portion 42a of the engine valve 42, and the engine valve 42 is rotated in the direction of the arrow by the workpiece rotation means 70 (first
(see figure).

Next, the ball screw 20.24 is rotated under the driving action of the servo motors 18 and 22 to move the first and second moving tables 14.16 in the directions of arrows X and Y, respectively.

Then, the grinding operation of the face surface 41 of the engine valve 42 is started by the first grindstone plate 43 of the grinding wheel 40 rotating in the direction of the arrow under the action of the drive motor 26.

In this case, as shown in FIG. 3, rough grinding abrasive grains 50 electrodeposited on the tapered surface 48 of the first grinding wheel plate 43 are applied to the face surface 41 of the umbrella portion 42a under the action of the servo motors 18 and 22. It is pressed in the direction of arrow A and rough grinding work is performed.

After the rough grinding work is completed, the servo motor 18
and 22, the first and second moving tables 14.16 are moved, and the second grinding wheel plate 44 of the grinding wheel 4° is moved.
comes into contact with the face surface 41 of the umbrella portion 42a. Next, the grinding wheel 40 is oscillated in the directions of arrows B and C under the action of the servo motors 18 and 22 to perform the final grinding operation.

In this way, the rough grinding work and the finish grinding work of the face surface 41 of the umbrella part 42a are performed continuously, and the grinding work of the face surface 41 is completed in a short time. Note that the rough grinding abrasive grains 5o are subject to greater grinding resistance from the workpiece than the finish grinding abrasive grains 58, and therefore are significantly worn out. In this case, by removing the bolt 6o and removing the first grindstone plate 43 from the second grindstone plate 44 and replacing it with a new one, it is possible to continue the grinding operation in the optimum condition again.

As described above, according to the present invention, the first grindstone plate having rough grinding abrasive grains and the second grindstone plate having finish grinding abrasive grains are removably arranged side by side, and the first grindstone plate Next to the rough grinding work using the second grindstone plate, the finishing grinding work is continuously performed using the second grindstone plate. Therefore, there is no need to replace the grinding wheel depending on the grinding process as in the conventional method, and the grinding work of the workpiece can be completed in an extremely short time. Also,
Since the rough grinding work and the finish grinding work are performed continuously, there is no positional shift with respect to the workpiece when replacing the grinding wheel as in the conventional case, and it is possible to obtain an extremely highly accurate ground surface. Furthermore, since the first and second grindstone plates are detachably connected, only the first grindstone plate, which has rough grinding abrasive grains that are more worn out than finish grinding abrasive grains, can be replaced as necessary. This has the effect of making it possible to perform precise grinding work using the most suitable abrasive grains at all times.

Although the present invention has been described above with reference to preferred embodiments, the present invention is not limited to these embodiments (various improvements and changes in design are possible without departing from the gist of the present invention). Of course.

[Brief explanation of the drawing]

FIG. 1 is an explanatory plan view showing the main body of a cylindrical grinder to which the grinding wheel and grinding method according to the present invention are applied, FIG. 2 is a cross-sectional configuration diagram of the grinding wheel according to the present invention, and FIG. 3 is a diagram showing the structure of the grinding wheel according to the present invention. FIG. 3 is an explanatory diagram of a grinding method using a grinding wheel according to the present invention. 10... Main unit 12... Bed 14.
...First moving table 16...Second moving table 1
8.22... Servo motor 26... Drive motor 32... Bearing portion 40... Grinding wheel 42
...Engine valve 43...First grindstone plate 44.
...Second whetstone vi50...Abrasive grain for rough grinding 5 days...Abrasive grain for finish grinding 66...Step part FIG, 2

Claims (5)

[Claims] (1) a first grinding wheel plate having rough grinding abrasive grains on its circumference;
A second grindstone plate having finish grinding abrasive grains is arranged in parallel on the circumference, and the rough grinding abrasive grains and the finish grinding abrasive grains are arranged continuously. Characteristic grinding wheel. (2) In the grinding wheel according to claim 1,
A grinding wheel in which a first grindstone plate and a second grindstone plate are detachably connected. (3) In the grinding wheel according to claim 1,
A grinding wheel in which the grinding surface of the first grindstone plate and the grinding surface of the second grindstone plate are tapered toward the rotation center axis of each grindstone plate. (4) In the grinding wheel according to claim 3,
The tapered surface of the first grinding wheel plate and the tapered surface of the second grinding wheel plate are determined by adjusting the distance from the rotation center axis of each grinding wheel plate so that the grinding surfaces made of abrasive grains attached to each tapered surface are continuous. The grinding wheel is selected according to the requirements. (5) A method of grinding a workpiece using a grinding wheel in which a first grindstone plate having rough grinding abrasive grains and a second grindstone plate having finish grinding abrasive grains are arranged side by side on the circumference. Then, the first grindstone plate is displaced toward the surface to be ground of the workpiece to perform rough grinding, and then the second grindstone plate is oscillated along the surface to be ground to perform finish grinding. A grinding method characterized by: