JP2647438B2 - Grinding machine for short and small workpieces with centerless grinder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an apparatus for grinding small workpieces by a centerless grinding machine, and more specifically, as shown in FIG. The present invention relates to an apparatus for grinding a small diameter b and a conical part c at both ends (or one side) by centerless grinding without grinding a central thick portion a.

[Conventional technology]

In the case of centerless grinding of a short workpiece W as shown in FIG. 8, the required accuracy is high (for example, 1 μm or less), the dimensional variation is severe (for example, 3 μm or less), and the processing time is short (for example, one cycle 7 seconds or less). The total grinding margin
It is necessary to machine about 0.1 φmax with an actual grinding time of about 3 seconds. In this case, the cutting speed of the grinding wheel is 0.05 / sec at the maximum. For this reason, as shown in FIG. 9, when the small diameter portion b, which is the ground surface of the workpiece W, is supported by the blade and the adjusting grindstone R, the conical portion c can be supported by the blade. However, if the position where the grinding wheel G first comes into contact with the workpiece is the conical portion c not supported by the blade or the adjusting grindstone, the workpiece jumps and causes an accident. When grinding as shown in FIG. 9,
Since the length of the portion where the adjusting grindstone R contacts is short, the adjusting grindstone R
There is a problem that the wear of the clothes becomes large, and a frequent dress is required.

For this reason, in centerless grinding of short and small workpieces as shown in FIG. 8, the precision of each part of the raw material is increased, and as shown in FIG. Usually, the small diameter portion b and the conical portion c are ground by the grinding wheel G while being supported.

However, when the grinding is performed as shown in FIG. 10, the instability of the workpiece in the initial stage of the grinding is greater than in the case of FIG. Therefore, when centerless grinding is performed as shown in FIG. 10, the workpiece W is pressed by an upper pressing shoe or the like to stabilize the workpiece during grinding, as shown in FIG. Have been.

[Problems to be solved by the invention]

As described above, in the grinding of short workpieces that require a short cycle time of 7 seconds or less, the time required for inserting and removing the workpiece must be reduced to about 2 seconds. However, it is impossible to insert a workpiece having an error in the axial direction, and it is necessary to insert the workpiece from above between the grinding wheel and the adjusting wheel. If the upper holding device as shown in FIG. It is necessary to retract the upper holding device at the time of insertion and removal of the workpiece, and thus it is not possible to grind, insert and remove the workpiece in a short time as described above.

The present invention improves the problems of the prior art as described above, shortens the grinding cycle time of short and small workpieces, and performs centerless grinding in a stable state by holding the workpiece with an upper presser during grinding. It is an object of the present invention to provide an apparatus for grinding short and small workpieces.

[Means for solving the problem]

In order to achieve the above object, the present invention has a pair of workpiece holders for holding a workpiece and an upper holder for pressing the upper part of the workpiece during grinding, and releases the gripping by the workpiece holder during grinding. First and second cassettes are constructed, and the first and second cassettes are attached to the distal ends of the first and second swing arms, respectively, and the bases of the first and second swing arms are attached to the first and second swing arms, respectively. A constant distance along the sliding direction so that it can rotate about 180 ° between the grinding machine and the opposite direction on a slide table installed so as to be able to slide in the direction perpendicular to the grinding wheel axis adjacent to the grinding machine. The cassette is turned upward at the swing arm turning position where the cassette is located on the opposite side of the grinding machine, and the cassette is turned down at the swing arm turning position where the cassette is inserted into the grinding machine. It is characterized in that it is composed as performing insertion and removal of the workpiece relative to the grinding machine by a turning of the slide table slide and the swing arm.

[Action]

As described above, the present invention has a pair of work holders for holding a work and an upper retainer for pressing an upper part of the work during grinding, and a first work for releasing the holding by the work holder during grinding. And a second cassette.
And a second cassette are mounted at the ends of the first and second swing arms, respectively, so that the bases of the first and second swing arms can be slid in a direction perpendicular to the grinding wheel axis adjacent to the grinding machine. The cassette is located on the opposite side of the grinder from the grinding machine so that it can be turned by about 180 ° between the grinding machine and the opposite direction on the slide table installed in the slide direction. In the swing position of the swing arm, the cassette faces upward, and in the swing position of the swing arm, in which the cassette is inserted into the grinding machine, the cassette faces downward. Since it is configured to take out, the workpiece loaded in one cassette is inserted into the grinder together with the cassette while the workpiece is being ground. Can be performed with the loading of the take-out and the new workpiece of the workpiece in the other cassette, thereby, the grinding cycle time of the workpiece very well as short, it is possible to perform stable centerless grinding.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is a plan view showing a main part of a device for grinding short and small workpieces by a centerless grinding machine of the present invention, and FIG. 2 is a front view of a part thereof. In these figures, G denotes a grinding wheel, R denotes an adjustment wheel, and a workpiece W is inserted from above into between the grinding wheel G and the adjustment wheel R, and the workpiece is adjusted with a blade (not shown). The workpiece is rotated by the rotation of the adjusting grindstone while being supported between the grindstones R, and the workpiece is ground at a high speed by the grinding grindstone G. Since the centerless grinding is well known, detailed illustration and description of the grinding machine are omitted.

In the present invention, a first work piece having a built-in upper presser for a workpiece is provided.
Using the cassette 1a and the second cassette 1b, the workpiece W is previously loaded into the first cassette 1a, and the workpiece W is placed between the grinding wheel G and the adjusting wheel R together with the first cassette from above. Inserting and grinding the workpiece, meanwhile, the workpiece W is loaded in the second cassette 1b, and when the grinding of the workpiece for each of the first cassettes is completed, the first cassette 1a is removed from the grinding machine. The second cassette 1b is inserted from above into between the grinding wheel G and the adjusting wheel R to perform the grinding of the workpiece, during which the processed workpiece in the first cassette is taken out and a new workpiece is loaded. Hereinafter, this is repeated to perform grinding.

FIGS. 1 and 2 show an example for carrying out the above-described method, in which a first cassette 1a is connected to a first swing arm.
2a, similarly, the second cassette 1b is mounted on the distal end of the second arm 2b, and the bases of the first and second swing arms 2a and 2b are mounted on the slide table 3 at regular intervals. The work held in the first and second cassettes can be inserted from above into the grinding wheel G and the adjusting wheel R together with the cassettes by rotating the slide of the slide table 3 and the first and second swing arms 2a and 2b. To do. That is, the slide table 3 is supported on the base 4 so as to be slidable in a direction perpendicular to the grinding wheel axis, and the first swing arm 2a and the second
The swing arm 2b is mounted so as to be able to turn about 180 ° between the direction of the grinding machine and the opposite side by driving the swing motors 5a and 5b. 6a and 6b are swing arm bearings.

Further, a mechanism for attaching and detaching a workpiece to and from the cassette is provided at a position where the first and second swing arms are on the opposite side of the grinding machine. For example, as shown in FIG.
The slide cylinder 8 is slidably mounted on a guide rail 7 fixed in parallel with the slide direction of the chuck, and a chuck support shaft 9 is attached to the slide cylinder 8 so as to be slidable and rotatable in the vertical direction. Chucks 10a, 10 at the tip of
b, and one of the chucks 10a is a swing arm.
When 2a and 2b are located in the opposite direction to the grinding machine, they are located on the workpiece exchange line of the first and second cassettes, and the other chuck 10b
Is located at a position corresponding to the position of the pitch conveyor 11, or vice versa. The pitch conveyor 11 is a conveyor for workpiece materials, and feeds the workpiece so that the workpiece materials are positioned on a first cassette workpiece exchange line and a second cassette workpiece exchange line sandwiching a workpiece insertion / extraction line.

The first and second cassettes have the same configuration and have a pair of workpiece holders for holding the workpiece and an upper holder for pressing the upper portion of the workpiece during grinding, and release the gripping of the workpiece holder during grinding. Use what you do.

4 to 7 show an example of the cassette. 4 to 7, reference numeral 2 denotes the first or second swing arm. A cassette frame 12 is fixed to the tip of the swing arm 2, and a pair of guide rods 13 are vertically mounted on the cassette frame 12, and the guide rods are attached to the lower surface of the cassette frame. And a stopper 15 at a position slightly apart from the upper surface of the cassette frame is pinned. The guide bar 13 has an upper holding block for the workpiece
16 are fitted so that they can slide up and down.
One workpiece holder 17 is fixed to the tip of the guide bar 13. The upper holding block 16 has a pin 16a projecting from the lower end thereof, and the pin 16a is inserted into a hole 12a formed in the cassette frame 12, and the hole bottom and the pin 16a are inserted.
The upper holding block 16 is urged in the direction of the workpiece holder 17 with a coil spring 18 for holding the upper part interposed between them. At the center of the top end of the upper holding block 16, a holding portion 16b for holding the large-diameter portion a of the workpiece W is formed, and a leaf spring made of a leaf spring having a C-shaped free end at the back. The other workpiece holder 19 is fixed, and is configured such that the workpiece W can be sandwiched by the leaf spring workpiece holder 19 and the jaws 17 a formed on both sides of the one workpiece holder 17. ing. Also, as shown in FIG. 7, the blade B of the centerless grinding machine is provided with a retreating inclined surface of the leaf spring workpiece holder 19 on the back side (opposite to the inclined surface for centerless grinding). Then, the work W is inserted into the grinding position together with the cassette, the swing arm is further rotated, the upper holding block 16 is pushed down by the upper holding coil spring 18, and the work W is moved between the blade and the adjusting grindstone by the holding portion 16b. , The tip of the workpiece holder 19 made of a leaf spring comes into contact with the inclined surface and expands, so that the workpiece holders 17 and 19 can eliminate the clamping. Although details of the chucks 10a and 10b are not shown,
Use a chuck that can hold or release both ends of the work by opening and closing it in the same manner as a normal chuck.

Since the apparatus of the present invention has the above-described structure, centerless grinding using the first and second cassettes in a very short cycle time can be performed as described below.

That is, first, the first swing arm 2a is aligned with the workpiece insertion / extraction line, the first swing arm 2a is turned in the direction of the grinding machine, and the workpiece is inserted into the grinding machine together with the first cassette 1a. Then, the workpiece W is pressed between the blade B and the adjusting grindstone R by the upper holding block 16 as shown in FIG. In the meantime, the work (material) conveyed by the pitch conveyor 11 lowers the chuck support shaft 9 in the direction of arrow A, opens and closes the chuck to grasp the work (material), and moves the chuck support shaft 9 to the arrow A. Then, the chuck supporting shaft 9 is rotated in the direction of arrow B to position the chuck holding the workpiece (material) on the second swing arm 2b on the opposite side of the grinding machine, and then the chuck is supported. The shaft 9 is lowered in the direction of arrow A, and the workpiece (material) is placed in the workpiece holder 17 of the second cassette.
Then, the chuck is opened and raised. In this way, while the workpiece (material) is loaded into the second cassette while grinding the workpiece for each first cassette, and the grinding for each first cassette is completed,
The swing arm 2a is turned to the opposite side of the grinding machine, and the second swing arm 2b is slid so as to coincide with the workpiece insertion / extraction line.
The swing arm 2b is turned in the direction of the grinder, and the workpiece is inserted into the grinder together with the second cassette for grinding.

In the meantime, the slide cylinder 8 is advanced as shown by the arrow C so that the chucks 10a and 10b are aligned with the first cassette workpiece exchange line. The work (material) is loaded into the first cassette 1a by rotating the shaft, and thereafter, this is repeated to perform centerless grinding of the short and small work.

FIG. 3 shows a cycle diagram of the grinding process using the two cassettes as described above. As shown in this figure, even if the processing time including advance of the grinding wheel, grinding, spark-out, and retreat of the grinding wheel is set to 4 to 5 seconds, the processing time by using the cassette can be reduced to 6 to 7 seconds.

〔The invention's effect〕

As described above, according to the present invention, there is an effect that the centerless grinding can be performed in a stable state by making the grinding cycle time of a short workpiece very short.

[Brief description of the drawings]

FIG. 1 is a schematic plan view showing the overall configuration of an apparatus according to an embodiment of the present invention, FIG. 2 is a front view of a main part thereof, and FIG. 3 is a grinding cycle diagram. FIG. 4 is a front sectional view showing an example of a workpiece cassette used in the present invention, FIG. 5 is a side view thereof, and FIG. 6 is a plan view of FIG. It shows the status. FIG. 7 is a side view of the cassette showing a state during grinding. FIG. 8 is a front view showing an example of the workpiece, FIG. 9 is an explanatory view of a conventional example showing a grinding state of the workpiece shown in FIG. 8, FIG. 10 is an explanatory view of the conventional example, and FIG. FIG. 11 is an explanatory diagram of a stabilizing method of the conventional example shown in FIG. 1a 1st cassette, 1b 2nd cassette, 2a 1st
Swing arm, 2b second swing arm, 3 slide table, 5a, 5b swing motor, 7 guide rail, 8 slide cylinder, 9 chuck support shaft, 10
a, 10b… chuck, 11… pitch conveyor, 16… upper holding block, 17… workpiece holder, 18… coil spring for upper holding, 19… other workpiece holder made of leaf spring, W… … Workpiece, G …… grinding wheel, R …… adjustment wheel,
B: Blade.

Claims (2)

(57) [Claims] 1. A first and a second work holder having a pair of work holders for holding a work and an upper holding member for pressing an upper part of the work during grinding, wherein the first and second holders are configured to release the work holder during the grinding. And the first and second cassettes are attached to the tips of the first and second swing arms, respectively, and the bases of the first and second swing arms are attached to a grinding wheel adjacent to the grinding machine. The cassette is placed at a certain interval along the slide direction so as to be able to turn approximately 180 ° between the grinding machine and the opposite direction on a slide table installed so as to be able to slide in the direction perpendicular to the axis. At the turning position of the swing arm located on the side opposite to the grinding machine, the cassette is directed upward, at the turning position of the swing arm where the cassette is inserted into the grinding machine, the cassette is directed downward,
An apparatus for grinding short and short workpieces in a centerless grinding machine, wherein the workpiece is inserted into and taken out of the grinding machine by the slide of the slide table and the swing of a swing arm. 2. The center according to claim 1, wherein a mechanism for attaching and detaching a workpiece to and from the cassette is provided at a turning position of a swing arm where the cassette faces upward and is opposite to the grinding machine. Grinding machine for short and small workpieces in a grinding machine.