JPH0230465A - Grinding method and device - Google Patents

Abstract

PURPOSE:To enable grinding of various shapes by rotating a rotary grindstone having a circular recessed face over the whole periphery and bringing the end face of a work into contact with the circular arcuate recessed face by approaching from one end of this circular arcuate recessed face in the direction crossing with the rotary center of the grindstone with revolving a round bar shaped work around its shaft center. CONSTITUTION:A rotary grindstone 1 is rotated and also approached from one end of the circular arcuate recessed face 4' formed over the whole periphery of this grindstone 1 in the direction crossing with the rotary center of the grindstone 1 with revolving a round shaft shaped work 3 around the shaft center thereof. Grinding is then executed in a spherical surface shape, etc., by bringing the end face of this work 3 into contact with this circular arcuate recessed face.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention is for forming the end of a workpiece such as a needle used for a needle hair ring or a round shaft into a spherical shape or the like for use in various types of equipment into a spherical shape. The present invention relates to a method and apparatus for grinding.

[Conventional technology]

Conventionally, a common method for grinding the end of a round shaft-shaped workpiece into a spherical shape is to use a grindstone having a concave surface that matches the shape of the object to be ground.

[Problem to be solved by the invention]

In the case of the conventional grinding method as described above, if the radius or shape of the surface to be ground changes, it is necessary to replace the grindstone with a grindstone having a concave surface corresponding to the radius or shape. Therefore, it is best to prepare a large number of grindstones with concave surfaces of various radii and shapes.
Alternatively, it is necessary to correct the recessed surface of the grinding wheel each time the radius or shape changes, which is time consuming and causes high costs.

In view of the above-mentioned problems with the conventional method, the purpose of this invention is to provide a method and device that can grind f of various sizes and any shape close to a spherical surface or a spherical surface without having to replace the grindstone. That is.

[Failure to solve the problem]

In order to achieve the object described in ``2'', this invention rotates a rotary grindstone having an arc-shaped concave surface over the entire circumference, and rotates a round shaft-shaped workpiece around its axis. It is characterized by grinding into a spherical shape etc. by entering from one end of the arc-shaped concave surface of the grindstone and bringing the end face of the workpiece into contact with the arc-shaped concave surface in a direction that intersects the rotation center of the grindstone. A rotating ram having an outer periphery formed into a single-lobed hyperbola and having a plurality of retainers for holding workpieces arranged on the outer periphery at a constant angle with respect to the rotational axis, and the above-mentioned drum. means for supplying a round shaft-shaped work between each retainer; a belt that moves the workpiece, and a banking play 1 that supports the end of the workpiece in the moving direction that is to be moved in the axial direction by the thrust generated by rotation, and the workpiece is moved along an arcuate path by this feeding means. The present invention provides a grinding device comprising a grindstone having an arcuate concave surface on its outer periphery for receiving the tip of a work and grinding the tip of the work into a predetermined shape.

〔Example〕

In the embodiment shown in FIG. 1, 1 is a grindstone fixed to the end of a rotating shaft 2, and 3 is a round shaft-shaped workpiece.

An arc-shaped recessed surface 4 is formed on the outer periphery of the grindstone 2 over the entire circumference.

2. When grinding the end of the workpiece 3 into a spherical surface a with a radius r as shown in FIG. Shinoru.

Then, the radius R concentric with the center 0 of the arc of the concave surface 40
When the work 3 is moved in parallel so that the center O6 of the work 3 at a position a radius r from the end face of the work 3 passes through the circular arc of 2, the end face of the work 3 becomes a spherical surface a.

To shape the grindstone in the above case, a diamond dresser 6 is fixed to the tip of a dresser holder 5 rotating around an axis 4 as shown in FIG. 3, and the entire circumference of the grindstone 1 is shaped with a radius Rp+r.

Further, as shown in Fig. 4, a diamond dresser 6 is rotatably attached to the tip of the dresser holder 5 by means of a shaft 7.
Even if the dresser boulder 5 is rotated about the shaft 4 while the dresser 6 is rotated about the shaft 7, the shape of the recessed surface 4 is the same as that in FIG. 2.

If the shape of the recessed surface 4' of the grindstone 1 matches the rotation and continuous feeding of the work 3, the end of the work 3 will be formed into a spherical surface.

FIG. 5 shows one embodiment of the drum, in which a plurality of retainers 12 are fixed at regular intervals on the outer periphery of a drum 11 and rotated in the direction of the arrow.

A belt 13 is pressed against the outer periphery of the drum 11 by rollers 14 and 15, and is driven in the direction of the arrow.

The workpiece 3 to be machined rolls down the chute 16'2, enters between the retainers 12 from below the tram 11, and enters the drum 11.
As the belt rotates, it rotates upward together with the retainer 12 and enters the inside of the belt 13.

Since the bell 1-13 is running in the opposite direction to the rotation direction of the drum 110, the workpiece 3 coming out from between the retainers 12
The outer periphery of the drum 11 is rubbed by the belt 13, rotates in the opposite direction to the drum 11, moves upward, and is ejected from the ejection chute 17.
is discharged to.

Since the above-described mechanism merely provides rotational motion to each workpiece 3, axial positioning is also required.

An example of a method for feeding the workpiece 3 in the axial direction is a method shown in FIG.

As shown in FIG. 6, the outer periphery of the drum 11 is processed into a single-leaf hyperboloid, and the drum
An imaginary line inclined at a constant angle with respect to the axis 19 of the work piece 1 is defined as a generatrix line 20 of the workpiece, and each retainer 12 is arranged so that the work piece 3 is along this generatrix line 20.

Figure 7 is a developed view in which the drum 11 rotates to the left and the belt 1
3 travels to the right, each work 3 rotates in the direction of the arrow, and moves while being pressed against the backing plays 1 and 21 by the force acting on the drum 11 and the work 3.

As is clear from the above, each workpiece 3 moves in an arc along the outer periphery of the drum 11 while rotating.

That is, in the case of FIG. 2, the workpiece 3 is moved laterally along the curved surface of the grindstone 1 while being advanced along a plane parallel to the center of rotation of the grindstone 1, but in the case of FIGS. In the case of the method of driving the workpiece 3 as shown in the figure, the workpiece is fed as shown in FIG.

That is, in FIG. 8, the workpiece 3 is rotated along an arc C centered on the revolution axis B of the workpiece, which is perpendicular or at a predetermined angle to the rotation axis 88 of the grindstone 1. 3 in the axial direction.

In this case, the end face of the workpiece must be polished into the desired shape, so if we consider the metal shape to be a spherical surface and try to match the grindstone forming method described above, we can polish the end face of the workpiece within a 90° range as shown in Figure 8. Grinding wheel 1 and workpiece 3 are adjusted so that the trajectory of the grinding point a of continuous contact from the tip to the outer periphery is obtained.
All you have to do is determine the relative position of .

As shown in Figure 8, the basics of the position are as follows: The grinding position of the tip of the workpiece is such that the axis of the workpiece is facing towards the center of the grindstone.

U. The end point position of the outer 9 surfaces of the workpiece must be in contact with the grinding surface of the whetstone somewhere.

Things.

2. The work must rotate on its own axis.

It is.

This condition can be illustrated by modeling the shape of the grindstone surface through which the workpiece passes, as shown in FIG. 9.

In other words, when the rotation of the workpiece 3 is taken into account, the inner surface of the ring-shaped tube is ground.

In the case of the grinding shown in FIG. 9, the grinding points are connected at the outer periphery of the ring-shaped tube within a 90° range as shown by the dotted line, and this line is assumed to be the grinding line.

In this way, if the series of grinding points on the outer peripheral surface of the tube are connected within the range of 90' of the cross section of the tube, it is possible to grind a predetermined workpiece shape.

The concept of the molding shape is that when the tubular ring shown in FIG. 9 is pressed against the grindstone surface, it is sufficient that the contact with the grindstone surface is along the grinding line.

Therefore, the work 3 can be applied to the grindstone in any relative direction as long as this condition is satisfied.

As an example, if a tubular ring is pressed against the grinding wheel surface like the 10th circle, and this ring and the grinding wheel surface are in contact with each other as shown by the dotted line in the figure, then instead of this tube, the ring shown in FIG. By applying the tip of the work 3 to the grindstone 1 using the workpiece 3 feeding mechanism as explained in FIG. 7, a predetermined grinding process can be performed by the rotation and revolution of the workpiece 3.

In other words, such a grindstone can be formed using a one-point forming diamond dresser by synchronizing the rotation angle at point P and the rotation angle at the tip of the dresser, as shown in the enlarged views of the ring tube shown in Figures 10 and 11. , the shape of the grindstone becomes a formed shape (horizontal dress).

Its shape is explained in Fig. 12. It is formed by horizontal dressing from the shaft end outer circumference P1 to the shaft end tip: P2, the workpiece matches the passing point of the dressing, and the trajectory to be ground is horizontal as shown in the figure. Represented by dress locus.

At this time, at 23 arbitrary dress positions, the grindstone is insufficiently formed by Δview with respect to the inner surface of the tube. This is caused by a deviation between the horizontal dress and the dress point that should originally be moved.

It goes without saying that the correct shape cannot be obtained unless this amount of dress shortage is corrected, and its numerical value is calculated using the following formula (1) or (1)'-
It may be corrected using the correction value - for the case of horizontal dressing.

x2/r2+y2/b2=1, x2 from y=Xtanα
/ r2+x"jan"α/-1, X2-(1/
r 2-t-tan2α/b2 ) △-x/cosα △-]/cosα[1/ (]/r2+ tan2α/
(R2cos2α+ 2 Rr + r 2) l
] ""=-=(f) In the 0 formula, α-45° is the maximum, and the horizontal dress trajectory is y with the α-45° direction as the y-axis.
When used as an axis, y″a cos4.5 x 10c・・・・・・・・・
■, which is consistent with Habo 0 formula.

If you understand this, it becomes like the 130th. In other words, the speed is increased by 4.5 times the turning angle of the draining arm, and a circular motion of eccentricity a from the turning center is transmitted to the dresser to correct it, or a cam of that shape is installed to correct the dresser tip. By doing this, you can obtain a regular grindstone shape.

In the above-mentioned grindstone forming method, we have explained how to form a grindstone when the workpiece is continuously fed on a rotating carrier, but since the basic form is point grinding as shown in Figure 1 above, the relative relationship between the grindstone and the workpiece is Various shapes that can be ground depending on the position and dressing radius can be obtained as shown in FIG. 15 based on the principle shown in FIG. 14.

In addition, by controlling the relative speed between the angular velocity of the reference point rotation and the rotational angular velocity of the Drezer rotation radius 2r at the reference point using two-axis time control and shaping the grindstone, the shape of the machining tip of the workpiece can be Can be freely ground within the range of the convex surface. This double-sided speed control--two-axis control can be easily executed, for example, by using a pulse motor as the power for reference point rotation and dresser rotation, and performing pulse control, or by a mechanical method such as gear transmission.

〔Effect of the invention〕

As described above, this invention rotates a rotary whetstone having an arc-shaped recessed surface over the entire circumference, and rotates a round shaft-shaped grain around its axis in a direction intersecting the center of rotation of the whetstone. Since the grinding wheel enters from one end of the arcuate recessed surface and brings the end surface of the workpiece into contact with the arcuate recessed surface,
It is possible to grind various shapes depending on the relative position of the grindstone and the workpiece and the dressing radius.

In addition, the device includes a rotating drum whose outer periphery is formed into a single-lobed hyperbola, and a plurality of retainers for holding workpieces are arranged on the outer periphery at a constant angle with respect to the rotational axis. This is because the workpiece is sent while being rotated by a means for supplying a round shaft-shaped workpiece between each retainer and a belt that attaches to the workpiece of the drum and rotates the workpiece in the opposite direction to the rotational direction of the drum. As the workpiece rotates on its own axis and is pressed against the backing plate by generating a thrust force, it is possible to securely hold the workpiece and maintain its length accuracy. Since the grinding process is performed by crimping the inlet surface, continuous grinding can be performed, making it suitable for mass production.

[Brief explanation of the drawing]

Fig. 1 is a front view showing the principle of the method of this invention, Fig. 2 is an enlarged front view showing the main parts of the same as above, Figs. 3 and 4 are enlarged front views showing the grinding stone state, and Fig. 50 is a workpiece. FIG. 6 is a perspective view showing details of the same drum, FIG. 7 is a developed view of the outer periphery of the above, and FIG. 8 is a perspective view showing the point at which the workpiece is ground by the grindstone. Figure 9 is a perspective view modeling the surface of the grindstone through which the workpiece passes, Figure 10 is a perspective view of the same as above in contact with the grindstone, Figure 11 is an enlarged perspective view of a part of the same as above, Figure 12 is The figures are a front view, a side view, and a cross-sectional view to explain the same as above in more detail, No. 13 is an explanatory diagram of the correction of the tip of the dresser, No. 141ffi is a front view of grinding states of various shapes, and Fig. 15 is a view of various finishes. It is a partially cutaway front view of the product. 1... Grindstone, 3... Work, 4'... Arc-shaped concave surface, 11... Drum, 12... Retainer, 13 ······belt. Patent applicant Ment Research Institute Co., Ltd. Agent Aya Kamata Figure 14 C and Figure 15

Claims (2)

[Claims] (1) Rotate a rotary grindstone having an arc-shaped recessed surface over the entire circumference, rotate the round shaft-shaped workpiece around its axis, and rotate the grindstone in a direction intersecting the rotation center of the grindstone. A grinding method characterized by grinding the workpiece into a spherical shape by entering from one end of the arcuate recessed surface and bringing the end face of the workpiece into contact with the arcuate recessed surface. (2) A rotating drum whose outer periphery is formed into a single-lobed hyperbola and on which a plurality of retainers for holding workpieces are arranged at a constant angle with respect to the rotational axis, and each retainer of the drum. means for supplying a round shaft-shaped work between the retainers; a belt that runs in the opposite direction to the rotation direction of the drum and contacts the work between the retainers to rotate the work in the opposite direction to the rotation direction of the drum; a workpiece feeding means consisting of a backing plate that supports the end of the workpiece in the moving direction that is about to be moved in the axial direction by the thrust generated by the movement; A grinding device consisting of a grindstone with an arc-shaped concave surface on the outer periphery for grinding the tip of a workpiece into a predetermined shape.