JPH03228557A - Grinding method for shaft end of work - Google Patents

Abstract

PURPOSE:To properly maintain the flatness of a shaft end and to increase the operation rate and productivity, by simultaneously moving a work and one part of grindstones in the direction orthogonal with the axial line of the work and the other part in the axial direction and grinding a scheduled grinding allowance while until the shaft end of the work passing through the grinding face of the grindstone. CONSTITUTION:An oblique lengthwise feed is given to a grindstone wheel 10 whole body by simultaneously moving a motor 12 in an X and Y directions, by actuating a pulse motor as well as rotating an engine value 1 and the grindstone wheel 10. When the shaft end 1a of the valve 1 is ground with the gist like this, the scheduled grinding allowance is uniformly distributed on the grinding face 11a whole body of the grindstone wheel 10 and the grinding face 11a is worn on the average, so the grinding face 11a is maintained in a flat face at all times. Consequently, there is no danger of spoiling the flatness of the shaft end 1a even in the case of correcting no grindstone 11 by a dresser, etc. Yet, the life of the grindstone 11 is prolonged because of the grinding face 11a whole body being effectively used and the processing quantity of the valve 1 per one grindstone 11 becomes plenty remarkably.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of grinding the shaft end of a rod-shaped workpiece, such as an engine valve, using a grinding wheel (hereinafter abbreviated as a grinding wheel).

[Conventional technology]

Figures 1 and 2 show the shaft end (1a) of the engine valve (1).
) is a schematic representation of the workpiece support part of a grinding machine for grinding.

A pair of front and rear drive rollers of the same diameter facing each other and spaced apart (
2) (2) are connected to each other by a drive shaft (3).

The circumferential drive roller (2) (2) is integrally rotated in a clockwise direction when viewed from the front by a driven gear (4) fixed to the front end of the drive shaft (3) meshing with the drive gear (5) and rotating. can be rotated.

(6) is a driven roller having the same diameter and size as the driving roller (2), which is adjacent to each driving roller (2) and aligned on the same plane as the driving roller (2), and the front and rear driven rollers (6) (6) are Driven shaft (7)
are connected to each other by.

The detail (1b) of the engine valve (1) is placed on the opposing surfaces of the opening drive roller (2) (2) and both driven rollers (6) (6), and the rotation axis ( It is pressed from above by a pressing roller (8) that is slightly inclined and can be raised and lowered.

The drive gear (5) is driven by a motor (not shown),
When the pressure roller (8) is rotated counterclockwise in front view and the pressure roller (8) is rotated clockwise in front view, the engine valve (1) applies thrust forward (downward in FIG. 1) Δ by the suppression roller (8). while being rotated counterclockwise when viewed from the front.

A loader head (9) which is rotatable and whose longitudinal position is adjustable is in contact with the entire surface (1c) of the engine valve (1), and the shaft end (1a) is moved by an arbitrary length in the tangential direction (first direction). It can be positioned by protruding from both rollers (2) and (6) of the upper part of the figure.

(10) is a grinding wheel whose left end faces parallel to the rear driven roller (6), and an annular grinding wheel (11) is attached to the peripheral edge of the surface facing the driven roller (6). is fixed.

(12) is a drive motor for the grinding wheel (10), which can move the grinding wheel (10) in the front and rear and left and right directions on a bed (not shown).

Next, the shaft end (1a) of the engine valve (1) with an irregular end face after the pressing and heat treatment process is processed using the above-mentioned grinding machine.
The conventional grinding method for grinding will be explained.

FIGS. 8(a) to (c) show the conventional grinding method. First, as shown in FIG. 8(a), the engine valve (],)
After placing the detail (1b) on both rollers (2) and (6), adjust the front and back position of the loader head (9) to align the shaft end (
1a) is brought close to the outer circumferential surface of the grindstone (11) and pressed with the pressing roller (8).

Next, as shown in FIG. 8(b), after moving the grinding wheel (10) forward (downward in the figure) by the amount of scheduled grinding,
While rotating the engine valve (1) and the grinding wheel (10), the grinding wheel (10) is connected to the grinding wheel (11) whose shaft end (1a) is annular.
) and grind the shaft end (1a).

Then, as shown in FIG. 8(c), the grinding wheel (10) is returned to the same position as in FIG. 8(a) to stand by for grinding the next engine valve (1).

[Problem to be solved by the invention]

The shaft end of an engine valve is an important part that comes into direct contact with a rocker arm and the like and receives large repeated loads when the valve is opened and closed, and therefore requires high flatness.

As in the conventional grinding method described above, the grinding wheel (10) is
Simply move the shaft end (1a) until it passes the grindstone (IJ) and grind the shaft end (lb) at one time.
As shown in the figure, the part of the shaft end (1a) that hits the grinding wheel (11) more strongly, that is, the outer periphery, the more the abrasive grains fall off, and as more engine valves (1) are ground, the grinding surface ( The flat part of lla) gradually wears away, and the whole becomes inclined.

If the grinding is continued in this state, the shaft end (la) will also be inclined and the flatness will be impaired, so it is necessary to periodically correct the grinding surface (lla) with a dresser to make it a flat surface.

In the past, flat parts wore out relatively quickly, the number of workpieces that could be ground with one correction was limited, and one machine had to be stopped each time a correction was made, resulting in poor machine utilization and productivity. There wasn't.

In addition, when making corrections with a dresser, it is necessary to grind down the grinding surface (lla) of the grindstone (11) to the most worn part to make it a flat surface, but this reduces the lifespan of the grindstone (11) and requires replacement. frequency also increases.

The present invention was made to solve the above problems, and by maintaining the flatness of the work shaft end properly without modifying the grinding surface of the whetstone, the loss time required for modifying or replacing the whetstone can be reduced. It is an object of the present invention to provide a method for grinding the shaft end of a workpiece, which eliminates the problem and thereby improves the operating rate and productivity of the machine.

[Means to solve the problem]

In order to achieve the above object, the method of the present invention is a grinding method in which the shaft end of a workpiece is ground by a grinding wheel rotating around an axis parallel to the axis of the workpiece, and one of the workpiece and the grinding wheel. is simultaneously moved in the direction perpendicular to the axis of the workpiece and the other in the axial direction, and the planned grinding allowance is ground until the shaft end of the workpiece passes the grinding surface of the grinding wheel. It is a feature.

Further, the above object is to simultaneously move the workpiece and the grinding wheel relative to each other in a direction perpendicular to the axis of the workpiece and in the axial direction of the workpiece, while the axial end of the workpiece is brought into contact with the grinding surface of the grinding wheel. This can also be achieved by grinding the planned grinding allowance during the pass.

[For production]

According to the method of the present invention, the scheduled grinding allowance at the end of the workpiece shaft is uniformly distributed over the entire grinding surface, so that the entire grinding surface is worn evenly and is always maintained as a flat surface.

As a result, the flatness of the work shaft end is maintained appropriately.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 3 shows how the shaft end (1a) of the engine valve (1) is cut using the grinding machine shown in FIGS.
) shows the procedure for grinding according to the invention method described in (1).

The motor (12) in the above-mentioned grinding machine used to carry out the method of the present invention moves over the bed (not shown) by means of a feed screw mechanism linked to a pulse motor (when shown), etc., as shown in the third drawing. , is subjected to two-dimensional NC control in a direction perpendicular to the axis of the engine valve (1) (X direction, left-right direction in FIG. 1) and in the axial direction (Y direction).

First, as in the conventional method described above, the engine valve (1)
After placing the shaft part (1b) on both rollers (2) and (6), adjust the loader head (9) so that the shaft end (1a) is almost in contact with the grinding surface (lla) of the grindstone (11). Position it so that it is in the same position, and use the pressure roller (8) to remove the detail (lb).
Press.

Next, the engine valve (1) and the grinding wheel (10) are rotated, and the pulse motor is activated so that the motor (
12) in the X direction and the Y direction simultaneously as shown in the third figure, and a diagonal forward force, that is, a feed in the Z direction indicated by the arrow, is applied to the entire grinding wheel (10).

In this case, from the start of machining when the shaft end (1a) comes into sliding contact with the outer peripheral end of the grinding surface (lla), the shaft end (la)
) The feed speed (vx) in the X direction of the grinding wheel (10) in the The feed speed (Va) of the grinding wheel (10) is calculated and set in advance using the following formula, and the feed of the grinding wheel (10) in the X and Y directions is controlled by the NC control system ( The grinding process is controlled by the position.

vx= d / t vy = h / t Here, d is the moving distance of the grinding wheel (lO) in the X direction from the start of processing to the end of processing, that is, in this example, the grinding surface of the grinding wheel (11) ( lla) width.

When the shaft end (la) is ground in this way, as shown in Fig. 4, the planned grinding allowance (h) is evenly distributed over the entire grinding surface (lla), and the grinding surface (lla) ) wears out evenly, so the grinding surface (lla) always remains flat. Therefore, even if the grindstone (11) is not modified using a dresser or the like, there is no risk of damaging the flatness of the shaft end (la).

Moreover, since the entire grinding surface (lla) is effectively used, the life of the grinding wheel (11) is extended, and the number of workpieces processed per grinding wheel is significantly larger than in the conventional method.

In the above embodiment, the workpiece side is fixed and feed is applied to the grindstone side, but on the contrary, as shown in Figure 5, the grindstone (11) is set as the fixed side and feed is applied to the workpiece side in the Z direction. It is also possible to give a feed of .

6 and 7 show the grinding procedure in the invention according to claim (2), and the embodiment shown in FIG. 6 has a grinding wheel (10
) is ground in the X direction (left side in the figure) perpendicular to the axis of the workpiece, and the engine valve (1) is simultaneously moved in the axial direction (Y direction).

Moreover, in the embodiment shown in FIG. 7, contrary to the above, the grinding wheel (
10) in the Y direction, and the engine valve (1) is simultaneously moved in the X direction from the outer peripheral end to the inner peripheral end of the grindstone (11).

The method of the invention described in claim (2) can also provide the same effects as described above.

In addition, the invention method described in claims (1) and (2) above includes:
In both cases, the planned grinding amount is ground only in the forward pass of the grindstone (11) or the workpiece, but for example, when the planned grinding allowance of the workpiece is large, the scheduled grinding amount is ground by the forward pass and return pass of the grindstone or workpiece. It is also possible to grind half of each part.

〔Effect of the invention〕

According to the method of the present invention, the entire grinding surface of the grindstone wears uniformly and is always maintained flat, so the flatness of the workpiece shaft end can be kept within the allowable range without modifying the grinding surface. I can do it.

Furthermore, since the entire grinding surface can be used effectively, the life of the grindstone is extended, and the loss time required for corrections and replacements is significantly reduced, increasing the operating rate and productivity of the machine.

[Brief explanation of drawings]

1 is a schematic plan view of the essential parts of a grinding machine used for carrying out the method of the present invention; FIG. 2 is a longitudinal sectional front view taken along line A-A in FIG. 1; and FIG. 4 is an enlarged cross-sectional plan view of the main part showing the grinding procedure according to the invention described in ), FIG. , Similarly, FIGS. 6 and 7 are enlarged cross-sectional plan views of essential parts showing other embodiments. FIGS. (a) to (C) are enlarged cross-sectional plan views of essential parts showing the grinding procedure of the conventional method, and FIG. 9 is a cross-sectional plan view exaggerating the state of wear of the grindstone in the conventional method. (1) Engine valve (work) (1a) Shaft end (1b) Details (2) Drive roller (4) Driven gear (6) Driven roller (8) Suppression roller (10) Grinding wheel (lla) Grinding surface (h) Planned grinding allowance (3) Drive shaft (5) Drive gear (7) Driven shaft (9) Loader head (11) Grinding wheel (12) Motor (d) Grinding wheel width (1 other person) Fig. 5 1n Fig. 8 Fig. 9 figure

Claims (2)

[Claims] (1) A grinding method in which the shaft end of a workpiece is ground by a grinding wheel that rotates around an axis that is parallel to the axis of the workpiece, and one of the workpiece and the grinding wheel is rotated in a direction perpendicular to the axis of the workpiece. A method for grinding a shaft end of a workpiece, the method comprising: grinding a planned grinding allowance while simultaneously moving the other end in the axial direction until the shaft end of the workpiece passes the grinding surface of a grinding wheel. . (2) A grinding method in which the shaft end of the workpiece is ground by a grinding wheel rotating around an axis parallel to the axis of the workpiece, the workpiece and the grinding wheel being rotated in a direction perpendicular to the axis of the workpiece, A method for grinding a shaft end of a workpiece, comprising: grinding a planned grinding allowance while the shaft end of the workpiece passes through a grinding surface of a grinding wheel while simultaneously moving the workpiece relatively in the axial direction.