JPH04348859A - Method for centerless grinding - Google Patents

Abstract

PURPOSE:To grind a long workpiece accurately and efficiently. CONSTITUTION:A workpiece (W) is ground by through reciprocation which reciprocates the workpiece (W) one or more times between a grinding wheel (1) and a regulating wheel (2). By this operation, the workpiece (W) can be ground accurately, because the workpiece (W) is ground more than one time passing through between the grinding wheel (W) and the regulating wheel (2). In addition, because the workpiece (W) reciprocates, it is not necessary to return the workpiece (W) from the exit to the inlet of the grinding machine, and it is possible to grind the workpiece (W) in a short time and to automate the grinding operation easily.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a centerless grinding method particularly suitable for long workpieces.

0002

[Prior Art] In a conventional centerless grinding machine that performs through-feed grinding, a workpiece is fed in a fixed direction between a grinding wheel and an adjustment wheel, and grinding is performed during this time. .

0003

[Problem to be Solved by the Invention] When grinding a long workpiece using the conventional centerless grinding machine described above, it is not possible to remove the bend in the long workpiece with one normal through-feed grinding, so it is necessary to grind the long workpiece several times. It is necessary to perform feed grinding. However, with conventional centerless grinders, the workpiece is only fed in one direction as described above, so it is difficult to automate multiple through-feed grinding operations. For this reason, conventionally, the operator has to repeat the work of receiving the workpiece at the exit of the grinding machine and carrying it in from the entrance of the grinding machine each time, resulting in a problem that the work is troublesome and time-consuming.

[0004] The purpose of the present invention is to solve the above problems,
The purpose of the present invention is to provide a method for grinding long workpieces with high precision and efficiency.

[0005]

[Means for Solving the Problems] The centerless grinding method according to the present invention is characterized in that a workpiece is ground by reciprocating feeding between a grinding wheel and an adjusting wheel once or multiple times.

[0006] The switching drive of the feed angle of the adjusting wheel according to the feed direction of the workpiece and the switching drive of the swivel angle of the adjusting wheel are sometimes performed by numerical control using a computer.

[0007]

[Operation] Since the workpiece is ground by passing it between the grinding wheel and the adjustment wheel multiple times, it is possible to grind the workpiece with high precision. In addition, since the workpiece is reciprocated, there is no need to return the workpiece from the outlet to the inlet of the grinder, and grinding can be done in a short time and automation is easy.

[0008] If the switching drive of the feed angle of the adjusting wheel and the swivel angle switching drive of the adjusting wheel depending on the feeding direction of the workpiece are performed by numerical control using a computer, setting and control are easy.

[0009]

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings.

1 to 3 show a schematic structure of a centerless grinding machine, FIGS. 4 and 5 show a specific structure of its main parts, and FIG. 6 shows an electrical structure. In the following description, the left side of FIGS. 1 and 2 will be referred to as the front, the right side will be referred to as the rear, and the left and right sides when viewed from the front to the rear will be referred to as the left and right.

As shown in FIGS. 1 to 3, the grinding machine includes a grinding wheel (1) and an adjusting wheel (2) arranged side by side. The rotation axis (1a) of the grinding wheel (1) extends horizontally in the front-rear direction. The rotation axis of the adjustment wheel (2) (
2a) extends in the front-rear direction, and as described later, the angle of the rotation axis (2a) in the horizontal plane (swivel angle) and the angle of the rotation axis (2a) in the vertical plane (feed angle) can be adjusted. It has become. A receiving plate (blade) (3) is provided below between the grinding wheel (1) and the adjusting wheel (2). The adjustment wheel (
2) A workpiece receiving surface (3a) is formed which is inclined to the side. A pair of front workpiece guides (4) on the left and right are provided in front between the grinding wheel (1) and the adjustment wheel (2), and a pair of rear workpiece guides (5) on the left and right are provided behind the same.

Although illustration of the specific configuration is omitted in FIGS. 1 to 3, there is a front workpiece transfer device in front of the grinding wheel (1) and adjustment wheel (2), and a rear workpiece transfer device behind the grinding wheel (1) and adjustment wheel (2). It is provided. These conveyance devices can switch the conveyance direction of the workpiece (W), and can move the workpiece (W) in either direction.
It is now possible to transport. Note that the front conveyance device and rear conveyance device are indicated by symbols (6) and (7) in Figure 6.
is shown. Additionally, a first limit switch (LS) (8) is installed at an appropriate location on the front transport device (6), and a second limit switch (LS) (8) is installed at an appropriate location on the rear transport device (7).
LS) (9) is provided.

As shown in FIGS. 4 and 5, a swivel table (10) is attached to the base of a grinding machine (not shown). Although illustration of the specific configuration is omitted, the swivel table (10) can be rotated about a vertical axis by a swivel angle adjustment motor. The swivel angle adjustment motor and its drive device are shown in FIG.
is shown.

[0014] An adjustment platform (13) is mounted on the swivel platform (10) so as to be movable horizontally in the left and right directions. The adjustment chassis (13) has a hollow box shape, and a feed angle adjustment shaft (14) is rotatably supported on its left end wall (13a) via a metal bearing (15). Adjustment axis (14)
extends in a horizontal direction parallel to the moving direction of the adjustment chassis (13), and a worm wheel (16) is fixedly provided at the right end of the adjustment shaft (14) within the platform (13). Adjustment chassis (
A worm shaft (17) extending approximately horizontally from front to back on the inner surface of the left end wall (13a) of 13) is rotatably supported via a plurality of bearings (18), and this shaft (17) has a worm wheel (16) and a A mating worm (19) is provided in a fixed manner. The worm shaft (17) passes through the rear wall (13b) of the adjustment chassis (13) and extends forward.
The feed angle adjustment motor (2
0). The adjustment motor (20) consists of a servo motor, the drive of which is designated by the reference numeral (21) in FIG.

Immediately to the right of the left end wall (13a) of the adjustment chassis (13), recesses (
22) is formed, and the left end wall (13a) of each recess (22)
A clamp cylinder (23) is fixed facing left. The rod (23a) of each cylinder (23) passes through the left end wall (13a), and a disk-shaped clamp plate (24) is fixedly provided at the left end thereof. In addition,
The driving device for these cylinders (23) is shown in FIG.
5).

An adjustment wheel cover (26) is arranged on the outer surface of the left end wall (13a) of the adjustment chassis (13). cover(
26) is approximately box-shaped with openings on the left side and the left side of the bottom.
A low circular protrusion (27) formed on the outer surface of its right end wall (26a) is fitted into a shallow circular recess (28) formed on the outer surface of the left end wall (13a) of the adjustment chassis (13). The left side of the adjustment shaft (14) is the cover (26).
A hole (29) formed in the center of the right end wall (26a) of
penetrates through and is fixed with a key (30) and nut (31). A protective cover (32) that covers the end of the adjustment shaft (14) and the nut (31) is attached to the inner surface of the right end wall (26a) of the cover (26).

Arc-shaped clamp grooves (33) centered around the hole (29) are formed on the outer surface of the right end wall (26a) of the cover (26) at four locations on the top, bottom, front and back. One end of these grooves (33) is open to the front or rear surface of the cover (32). On the outer surface of the right end wall (26a), projecting portions (34) are formed on both sides of each groove (33) so as to approach each other. The rod (23a) of the corresponding cylinder (23) is passed between the overhangs (34) of the grooves (33), and the clamp plate (24) is fitted into the grooves (33) at the back thereof. Then, by retracting the four cylinders (23) and moving (retracting) the rod (23a) to the right, the cover (26) is brought into pressure contact with the adjustment chassis (13) and clamped, and conversely, the cylinder ( The cover (26) is unclamped by extending the rod (23) and moving (advancing) the rod (23a) to the left.

Front and rear walls (26b) (2) of the cover (26)
6c), both ends of the shaft of the adjusting wheel (2) are rotatably supported;
A part of the adjustment wheel (2) protrudes to the left side of the cover (26). Although not shown, the adjustment wheel (2) is rotated in a constant direction at a constant speed by a motor. Note that the adjustment wheel drive motor and its drive device are shown in FIG. 6 by reference numerals (35) and (36).

The grinding wheel (1) is also rotated by the motor in a constant direction at a constant speed. Note that the grinding wheel drive motor and its drive device are shown in FIG.
8).

As described above, by rotating the feed angle adjustment motor (20) with the adjustment wheel cover (26) unclamped, the adjustment shaft (14) rotates, and the adjustment wheel rotates around the adjustment shaft (14). (2) is also tilted and its feed angle is adjusted, and by stopping the adjustment motor (20) and clamping the cover (26), the adjustment wheel (2) is fixed at an arbitrary feed angle. When the feed angle is adjusted so that the front side becomes higher as shown by the solid line in Fig. 1, a backward thrust is applied to the workpiece (W) by the rotation of the adjustment wheel (2), and conversely, as shown by the chain line in Fig. When the feed angle is adjusted so that the rear side becomes higher as shown in , a forward thrust is applied to the workpiece (W) by the rotation of the adjustment wheel (2). Further, by rotating the swivel table (10) with the swivel angle adjustment motor (11), the adjustment wheel (2) is tilted in a horizontal plane, and its swivel angle is adjusted.

As shown in FIG. 6, the grinding machine is equipped with a computer numerical control device (CNC device) (39). This device (39) uses a computer to control the entire grinding machine, and each of the above-mentioned parts is connected to it.

[0022] The CNC device (39) is capable of setting the number of repetitions of through-grinding.

In the above grinding machine, grinding is carried out as follows.

First, the workpiece (W) is loaded (placed) into a predetermined position of the front transport device (6) by the loading device. Note that this may be done by an operator. At this time, the front and rear conveyance devices (6) and (7) are being driven backward, and the feed angle of the adjustment wheel (2) is adjusted in a direction that generates backward thrust, as shown by the solid line in Figure 1. . In addition, the swivel angle is adjusted so that the distance between the grinding wheel (1) and the adjustment wheel (2) is slightly wider on the front side. When the workpiece (W) is loaded into the front transport device (6), the workpiece (W) is moved backward by the transport device (6), and the workpiece (W) is moved between the grinding wheel (1) and the adjustment wheel (2). Enter from the front with a wider gap between them. When the rear end of the workpiece (W) comes into contact with the grinding wheel (1) and the adjustment wheel (2), a backward thrust is applied to the workpiece (W) due to their rotation, and the workpiece (W)
W) is retracted over the backing plate (3), during which time the grinding takes place. The workpiece (W) that comes out from between the grinding wheel (1) and the adjusting wheel (2) is sent to the rear by the rear transport device (7), as shown by the chain line in Figures 1 and 2.
When the workpiece (W) retreats further and leaves the grinding wheel (1) and adjustment wheel (2), the second LS (9) is activated, the rear transport device (7) is stopped, and the workpiece (W) is W)
is stopped. Then, as shown by the chain line in Figure 1, the feed angle of the adjustment wheel (2) is switched to the opposite direction to generate forward thrust, and the swivel angle is also changed so that the distance between the grinding wheel (1) and adjustment wheel (2) is The rear side can be changed to be a little wider. Next, the front and rear transport devices (6) and (7) are driven forward, the workpiece (W) is advanced, and the grinding wheel (
Enter from the rear side where there is a wider gap between 1) and adjustment wheel (2). When the front end of the workpiece (W) comes into contact with the grinding wheel (1) and the adjustment wheel (2), the adjustment wheel (2) has the opposite feed angle, so their rotation causes the workpiece (W
), forward thrust acts on the workpiece (W), and the workpiece (W)
3) Advances above, during which grinding is performed. The workpiece (
W) is sent forward by the front transport device (6),
As shown by the solid lines in Figures 1 and 2, when the workpiece (W) moves further forward and separates from the grinding wheel (1) and adjustment wheel (2), the first LS (8) is activated and the front The transport device (6) is stopped and the workpiece (W) is stopped. Then, the feed angle and swivel angle of the adjusting wheel (2) are switched to the previous state again, and the workpiece (W) is
is sent later to perform the grinding. Then, such an operation is repeated a set number of times. Workpiece (W
) Each time the feed direction of the workpiece (W) is switched, the adjustment wheel (2) is given a small depth of cut, the outer diameter of the workpiece (W) is finished, and the bending accuracy is also gradually improved.

[0025]

According to the method of the present invention, as described above, a long workpiece can be ground with high precision and efficiency, and automation is also easy.

Furthermore, setting and control are facilitated by numerically controlling the feed angle of the adjusting wheel and the swivel angle of the adjusting wheel according to the workpiece feeding direction by numerical control using a computer.

[Brief explanation of drawings]

FIG. 1 is a schematic right side view of a centerless grinding machine showing an embodiment of the present invention.

FIG. 2 is a schematic plan view of the centerless grinding machine.

FIG. 3 is a sectional view taken along line III-III in FIG. 1;

FIG. 4 is a partially cutaway front view showing an enlarged portion of the adjustment wheel.

5 is a sectional view taken along line V-V in FIG. 4. FIG.

FIG. 6 is a block diagram showing the electrical configuration of the centerless grinder.

[Explanation of symbols]

(1) Grinding wheel (2) Adjustment wheel

Claims (2)

[Claims] 1. A centerless grinding method characterized in that a workpiece is ground by reciprocating feeding between a grinding wheel and an adjusting wheel once or multiple times. 2. The centerless grinding method according to claim 1, wherein the switching drive of the feed angle of the adjustment wheel and the swivel angle switching drive of the adjustment wheel according to the feed direction of the workpiece are performed by numerical control using a computer.