JP2002283168A - Machining method of work in machining center - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a similar function to a locating pin to be replaced with a tool, like a tool, without attaching a locating pin, which is a work positioning reference, to a work table. SOLUTION: When positioning a work W on a tilt-type work table 25, a locating pin 27 provided on a main shaft 1 of a machining center is inserted into the work table 25 to serve as a reference for positioning the work W. The hole H1 on the work W side into which the locate pin 27 has been inserted is to be cut.
If the workpiece W is clamped by the clamper 8, the spindle 1
The locate pin 27 is pulled out by the autonomous operation of. The main shaft 1 is changed from the locate pin 27 to a predetermined cutting tool, and then the work W is cut.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of machining a work in a machining center, and more particularly to a locating apparatus for positioning a work by involving a spindle in positioning of a work other than actual machining and in paying out the worked work. The present invention relates to a method of machining a work in a machining center that enables simplification of ancillary devices such as a work and a work dispensing device.

[0002]

2. Description of the Related Art FIGS. 4 and 5 show an example in which holes H1 and H2 are formed on a cylindrical workpiece W as shown in FIGS. 3A and 3B by a horizontal three-axis machining center. . As shown in the figure, the machining center MC has a main shaft 1 having three degrees of freedom of movement in orthogonal directions, and has a tool magazine 3 and an ATC arm 4 as main elements. Type worktable 5 and its worktable 5
Is provided with a work dispensing device 6 and the like below.

As a machining procedure, a worker M or a work input robot sets a work W on the work table 5 in a state where the work table 5 is appropriately tilted so that a work setting operation can be easily performed. As shown in FIG. 5, the work table 5 has a locate pin 7 which can be moved in and out by the operation of the cylinder 6, and a clamper 8 having a clamp lever 10 which is also driven by a clamp cylinder 9 as a main element. The workpiece W is fitted and positioned with reference to the located locate pin 7 and then clamped by the clamper 8. The inner circumference of the hole H1 to be fitted with the locate pin 7 serves as a reference at the time of positioning and is also a part to be processed. Therefore, when the work W is clamped, the locate pin 7 is removed from the hole H1 so as not to hinder the processing. fall back. Thereafter, the angle of the work table W is appropriately changed, and the process proceeds to actual cutting. It is well known that this cutting process is performed while appropriately changing tools between the spindle 1 and the tool magazine 3.

When the processing is completed, the work table 5 is in a horizontal state, for example, inverted, and the hinge type tilting type work discharge tray 11 in the work discharge device 6 is pushed up by the cylinder 12 to approach the work table 5. Then, after receiving the work W falling by its own weight due to the unclamping operation of the clamper 8, the work W descends again. Then, the work W left on the work delivery tray 11 is taken out by the worker M or the work unloading robot.

[0005]

In the above conventional structure,
Since it is necessary to attach a movable locating pin 7 and a cylinder 6 for driving the work table 5 to the work table 5, it is necessary to increase the load capacity of the work table 5,
It is necessary to arrange hydraulic and pneumatic piping using a rotary joint or the like on the movable worktable 5 itself, so that the cost of the entire worktable 5 increases. Further, the provision of the cylinder 6 inevitably increases the radius of rotation of the worktable 5 and thus the interference area, which limits the degree of freedom in designing the jig, which is not preferable. Similarly, since the cylinder 12 is indispensable for the work dispensing device 6, this also increases the cost.

The present invention has been made in view of such problems. Particularly, while ensuring the same or higher function as the conventional one, a cylinder for driving the above-mentioned locate pin, a cylinder of a workpiece discharging device, and the like are provided. The purpose of the present invention is to provide a processing method that can greatly simplify equipment by eliminating the use of the same.

[0007]

The invention according to claim 1 is based on the premise that the work to be machined is positioned and clamped on a work table of a machining center with reference to a locating pin, and then a cutting process is performed. .

In addition, a locating pin is included in a tool group handled by the automatic tool changer in advance, and the locating pin mounted on the main shaft of the machining center is moved before the positioning clamp of the workpiece. A step of positioning the work on the work seating surface with reference to the locating pin, and clamping the work with the locating pin as a reference. Removing the workpiece from the work seating surface using the degree of freedom of movement of the workpiece, and performing a machining process on the workpiece on the work table after changing the locating pin attached to the spindle to a cutting tool using an automatic tool changer. ,
It is characterized by including.

In this case, it is preferable that the work table is of a tilt type capable of tilting and displacing the position of the work together with the work table as described above. Desirable above.

Therefore, in the inventions according to the first and second aspects of the present invention, the locating pin is treated as one of the tools to be replaced, like the cutting tool, and the NC spindle itself is controlled by the tool. The locating pin is attached to and detached from the work table using the degree of freedom.

According to a third aspect of the present invention, based on the premise of the first or second aspect, the vertically movable work dispensing tray waiting below the work table is raised after the machining is completed. After the processed work is transferred onto the work payout tray by its own weight, the tray is lowered again together with the work, and the locating pin is engaged with the work payout tray. Is provided in advance.

After the machining is completed, the tool mounted on the main spindle is replaced by the locate pin again by the automatic tool changer, and the engaging means attached to the locate pin is moved to the work discharge tray using the degree of freedom of movement of the main spindle. The work payout tray is moved up and down while being engaged with the work.

In this case, it is desirable for the structure to simplify the structure that the work dispensing tray can be displaced up and down about the hinge pin as a rotation center.

Therefore, according to the third and fourth aspects of the present invention, in addition to the above-described operation of attaching and detaching the locating pin, up-and-down operation of the work delivery tray is performed using the degree of freedom of operation of the tool spindle.

[0015]

According to the first aspect of the present invention, a spindle which normally stands by at the origin position and is not operating at all at the time of exchanging a work other than the cutting work is an original function of the spindle. It is designed to actively participate in the detachment of the locating pin other than cutting. Therefore, since the workpiece is directly positioned by the spindle itself controlled by NC and then cut by the tool on the same spindle, the processing error caused by the workpiece positioning error is reduced, and the processing accuracy is lower than that of the conventional one. In addition to the above, there is no need to attach a locating pin or a cylinder for driving the work table to the work table side, so that the work table can be reduced in weight, the hydraulic and pneumatic piping can be simplified, and the cost can be reduced. The rotation radius of the work table can be reduced to contribute to an increase in the degree of freedom in designing the jig.

[0016] In particular, when the work table is of a so-called tilt type, as in the second aspect of the present invention.
In addition to the effects similar to those of the invention described in (1), there is an advantage that the work table itself or the work has an advantage in increasing the degree of freedom of posture.

According to the invention of claim 3, according to claim 2,
Also, based on the premise of the invention described in the third aspect, the vertical movement of the work dispensing tray is also performed using the degree of freedom of the movement of the main spindle. Therefore, in addition to the same effect as the invention described in the second or third aspect, In addition, the cylinder for driving the tray, which has been required in the past, can be eliminated, which can further contribute to simplifying equipment and reducing costs.

Further, when the tray is of a hinge-tilt type, the vertical movement of the tray itself can be easily and reliably performed by the main shaft, and the operation reliability is improved. There is.

[0019]

FIG. 1 is a view showing a preferred embodiment of a machining method according to the present invention. In particular, it is assumed that a machining center MC shown in FIG. 4 is used. 2 shows the relationship between a table 25 and a locate pin 27. 3 to 5 are denoted by the same reference numerals.

The table 25 is rotatably supported by the frame 13 shown in FIG. 4 with its center P as the center of rotation, and is rotatably driven by a drive motor (not shown). It is possible to stop at a position. The work base 25 has a work seating surface 2
A work sheet 21 having 1a is fixed, and a plurality of clampers 8 are provided as clamping means. The work W is clamped so as to be pressed against the work sheet 21. The clamper 8 is capable of displacing in the axial direction of the workpiece W and swinging.
It comprises a hydraulic or pneumatic type clamp cylinder 9 for unclamping operation. The table 25 and the worksheet 21 are formed with an insertion hole 22 having a diameter slightly larger than that of the worksheet 21 so that a locating pin 27 described later can be inserted thereinto.

On the other hand, the locating pin 27 is formed as a substantially rectangular shape bent from the root thereof, and is used for other cutting managed by the tool magazine 3 of the automatic tool changer 2 shown in FIG. Tool holder 2 common to tools
3 and is managed in exactly the same manner as those cutting tools, and is subject to automatic tool change between the tool magazine 3 and the spindle 1 of the machining center MC.

When the work W to be processed is set on the table 25, the table 25 is inclined at a predetermined angle as shown in FIG. 1, and the clamper 8 is in an unclamped state. Prior to this, the automatic tool changer 2 performs a tool change in response to a tool change command, and
Attach the locate pin 27 to Further, upon receiving the movement command, the spindle 1 approaches the table 25 while moving along a trajectory specified in advance using the degrees of freedom of the three orthogonal axes. The locate pin 27 is inserted into the insertion hole 22 from the side. That is, the main spindle 1 is located on the table 25 with the locate pin 2
7 is positioned at a predetermined three-dimensional position so as to protrude from the worksheet 21 by a predetermined amount, and waits in that state.

Next, when the work W is set so as to be seated on the work sheet 21 by the worker M or a work input robot, the work W is moved to the locating pin 27.
Is positioned based on Thereafter, when the start switch is turned on, each of the clampers 8 is actuated first to firmly clamp the previously positioned work W as if the work W is pressed against the work sheet 21.

After completion of the clamping, the spindle 1 is operated again, the spindle 1 is pulled out of the table 25 and returns to a position where the tool can be changed, and the spindle 1 is moved from the locate pin 27 by the automatic tool changer 2. Change to a specific tool for cutting.

When the position of the table 25 from which the locate pins 27 have been removed is changed to a predetermined machining position, the spindle 1 changed to a cutting tool approaches the table 25 again, and the positions of the holes H1 and H2 are changed. Actual cutting will be performed.

In this case, as shown in FIG. 3, the workpiece W needs to be machined into a plurality of holes having different directions.
Is to carry out machining while holding the cutting tool several times.

When all the holes required for one work W have been completed, the spindle 1 is replaced with the locating pin 27 again in preparation for the next work W, and the above operation is repeated thereafter.

As described above, according to the present embodiment, the locating pin 27 is provided on the main shaft 1 as if it were a cutting tool, and the work W is positioned while maintaining the relative positional relationship with the table 25. Therefore, the workpiece W is directly positioned by the spindle 1 itself controlled by the NC, and then the cutting is performed by a predetermined tool to be attached to the same spindle 1. Therefore, the workpiece positioning error is reduced. The resulting machining error is reduced to improve the machining accuracy, and it is not necessary to always attach the locate pin 7 and the cylinder 6 for moving the locate pin 7 to the table 25 as in the related art.

FIG. 2 is a view showing a preferred second embodiment of the processing method according to the present invention. In particular, on the assumption that the machining center MC shown in FIG. 4 is used, the work dispensing tray 31 and the locating pin 37 are connected to each other. Shows the relationship. That is, in the second embodiment, not only the detachment of the locating pin 37 with respect to the table 25 but also the vertical movement of the work dispensing tray 31 for receiving the processed work W from the table 25 is performed by the spindle 1. It was done.

As shown in FIG. 2, a work dispensing tray (hereinafter, simply referred to as a tray) 31 rotatable via a hinge pin 32 is provided on a base 30 below the table 25, and this tray 31 is on standby. It is rotatable and displaceable between a position Q1 and a work receiving position Q2. In addition,
A damper device 33 also serving as a stopper is provided further below the tray 31.

As described in connection with the prior art, when the work of the workpiece W positioned and clamped on the table 25 is completed, the table 25 is turned upside down so that the work W is on the lower side. When the tray 31 is tilted and displaced to the work receiving position Q2 so as to be close to the table 25 and the clamper 8 which has clamped the work W so far is operated in this state, the work W falls onto the tray 31 by its own weight. If the tray 31 is returned to the standby position Q1 after that, the work W can be taken out by the worker M or the work unloading robot, and the work W can be taken out. The vertical movement is performed via the locate pin 37 provided on the main shaft 1.

The locate pin 37 is mounted on the tool holder 23 so that the tool can be changed by the automatic tool changer 2 (see FIG. 4) in the same manner as in the first embodiment. A substantially hook-shaped hook portion 34 is integrally provided at the root portion as an engagement means. The tray 31 is provided with an extension 36 with which the hook portion 34 can be engaged.

The locating pin 37 is subjected to tool change by the automatic tool changer 2, and when the work W to be machined is set on the table 25, the locating pin 37 is mounted on the spindle 1 in exactly the same manner as in FIG. The work W is then inserted into the table 25 and used as a reference for positioning the work W with respect to the table 25. After this, the main shaft 1 is
7 is changed to a cutting tool in the same manner as described above, and a predetermined cutting process is performed on the work W.

On the other hand, when the cutting of the work W is completed, the table 25 is turned upside down so that the work W is on the lower side, and the spindle 1 is again changed from the cutting tool to the locating pin 37, and FIG. As shown in (3), approaching the tray 31 at the standby position Q1 using the degrees of freedom of the orthogonal three axes, engaging the hook portion 34 with the extension 36 on the tray 31 side, and the main spindle 1 moves the tray 31 by its autonomous operation. 31 is tilted while being raised to the work receiving position Q2 and held at that position.

When the clamper 8 on the table 25 performs the unclamping operation, the work W, which has been processed, falls down onto the tray 31 by its own weight and slides down to the lowest position R, and the main spindle 1 holds the tray on which the work W is placed. 31 is returned to the standby position Q1 again.

As described above, according to the present embodiment, the spindle 1
Performs autonomously not only the attachment and detachment of the locate pin 37 to and from the table 25 but also the vertical movement of the tray 31 using the locate pin 37.
It is not necessary to attach a locating pin to the device, and no driving means such as a cylinder is required for the vertical movement of the tray 31 for receiving the processed work W.

[Brief description of the drawings]

FIG. 1 is a diagram showing a first embodiment of the present invention, and is an explanatory diagram showing a mutual relationship among a work table, a locate pin, and a spindle.

FIG. 2 is a view showing a second embodiment of the present invention, and is an explanatory view showing the interrelationship between a work payout tray, a locate pin, and a spindle.

3A is a cross-sectional view showing an example of a work to be processed in a machining center, and FIG. 3B is a longitudinal cross-sectional view of FIG.

FIG. 4 is a schematic explanatory view showing a conventional machining mode in a machining center.

FIG. 5 is a configuration explanatory view showing details of a work table in FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Spindle 2 ... Automatic tool changer 8 ... Clamper 21a ... Work seating surface 23 ... Tool holder 25 ... Work table 27 ... Locating pin 31 ... Work discharge tray 32 ... Hinge pin 34 ... Hook part (engaging means) 36 ... Extension 37 ... Locating pin H1, H2: Hole MC: Machining center W: Work

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B23Q 7/00 B23Q 7/00 Z 7/08 7/08 A

Claims (4)

[Claims] 1. A method for performing a cutting process after positioning and clamping a work to be processed on a work table of a machining center on the basis of a locating pin, wherein the locating pin is previously included in a tool group handled by an automatic tool changer. Prior to the workpiece positioning clamp, the process of positioning the locating pin mounted on the spindle of the machining center on the workpiece seating surface of the work table using the degree of freedom of movement of the spindle. Positioning the workpiece and clamping the workpiece; waiting for the workpiece to be clamped; removing the locating pin from the workpiece seating surface using the freedom of movement of the spindle; and locating the locating pin mounted on the spindle with an automatic tool. After changing to a tool for cutting by the exchange device Method for processing a workpiece in a machining center which comprises a step of performing machining on the workpiece on the work table, a. 2. The method according to claim 1, wherein the work table is of a tilt type capable of tilting and displacing the posture of the work together with the work table. 3. A vertically movable work dispensing tray waiting below the work table is raised after the machining is completed, and the worked workpiece is transferred onto the workpiece dispensing tray by its own weight, and then the tray is re-opened. Is lowered with the work, and the locating pin is provided in advance with an engagement means capable of engaging with the work payout tray, and after the machining is completed, the tool mounted on the main spindle is moved by the automatic tool changer. The work take-out tray is moved up and down while holding the locate pin again and engaging the engaging means attached to the locate pin with the work pay-out tray using the degree of freedom of movement of the spindle. The method for processing a workpiece in a machining center according to claim 1, wherein: 4. The method according to claim 3, wherein the work dispensing tray is capable of tilting and displacing up and down around a hinge pin as a rotation center.