JP7383278B2 - Work holder for processing machines - Google Patents

Description

The present invention relates to a workpiece holder for a processing machine for fixing a workpiece to the processing machine.

As a work holder for this type of processing machine, the present applicant has developed a holder body that is circular in plan view, a base portion on which the work is placed on the upper surface of the holder body, and a plurality of jaws that clamp the work on the base portion. and an inclined surface having a surface normal rising toward the base portion is formed on the clamp portion of the jaw for chucking the workpiece, and the inclined surface and the workpiece face the inclined surface. The workpiece is pressed against the base part by this contact force, and the end of the holder body opposite to the base part has notches of different depths. We propose a configuration in which the part is formed symmetrically with respect to the axis to become an HSK standard cylindrical fitting part, and this cylindrical fitting part is fitted to a cylindrical fixing jig protruding from the table. (Patent Document 1).

JP2008-264983A

In the work holder (vise) for a processing machine shown in Patent Document 1, the movable jaw moves relative to the fixed jaw on one side to chuck the work, so the axis of the work is the axis of the work holder (rotation center). There is a problem that is difficult to match.

Under the above circumstances, it is an object of the present invention to easily align the axis of a workpiece with the axis of a workpiece holder.

In order to achieve the above-mentioned object, this invention fits the mounting part of the workpiece into the mounting hole of the holder body, aligns and centers the axes of the holder body and the workpiece, and presses the workpiece with the jaws of the holder body. This is to prevent it from coming off from the mounting hole.
If the mounting hole and workpiece mounting part are formed accurately and the center of the mounting hole is aligned with the axis of the holder body, the workpiece will fit into the mounting hole and the axes of the workpiece and the holder body will align (center). The workpiece's runout accuracy is fixed, and the lengthwise (axial) accuracy of the workpiece is ensured by pressing the workpiece with the jaws.

The specific configuration is for a processing machine, which includes a mounting hole on the top surface of the main body into which a workpiece mounting part (chucking part) fits, and a jaw around this mounting hole that presses the workpiece toward the center of the mounting hole. In the work holder, the mounting hole is formed into a circular shape in plan view that is the same size as the mounting portion of the workpiece, and the mounting portion fits snugly into the mounting hole, and the circumferential surface of the mounting hole is aligned with the reference plane in the radial direction of the workpiece ( The bottom surface of the mounting hole or the outer peripheral surface of the opening side edge of the mounting hole serves as the reference surface in the axial direction of the workpiece, and the jaw presses the workpiece. An inclined surface having a normal to the surface that stands up toward the mounting hole is formed on the pressing part, and the jaw moves with respect to the mounting hole by threaded connection with an adjustment bolt to connect the inclined surface and the workpiece. The structure is such that an inclined surface formed to face the inclined surface comes into contact with the part, and the workpiece is pressed into the mounting hole by this contact force.

To chuck (mount) a workpiece to a workpiece holder with this configuration, a mounting part for centering is formed in advance on the mounting surface of the workpiece, and the mounting part is fitted into the mounting hole of the workpiece holder body to center the workpiece. This is a method of chucking the workpiece to the holder by pushing the mounting part inward with the jaws in this state to prevent the workpiece from slipping out of the mounting hole (fixing it in the axial direction).

At this time, if an inclined surface having the above surface normal is formed on the clamping portion (pressing portion) of the jaw, a force directed toward the attachment hole can be applied to the inclined surface of the workpiece that the jaw contacts. That is, the workpiece can be firmly pressed against the mounting hole, and troubles such as the workpiece moving or coming off during processing can be prevented. The angle of this inclined surface is not particularly limited as long as it applies a force in the direction of the mounting hole, but is within a range that can be easily machined, such as an angle of 45 degrees or 60 degrees with the mounting hole. It is preferable to set the angle to .

In addition, there may be a plurality of the jaws, and each jaw may be arranged so as to move toward and away from the center of rotation, or the clamp portions of the respective jaws may be arranged so as to face each other, so that each jaw is It can be made so that it can move towards and away from the camera in the direction of In this way, the pressing force from the jaws will work toward the axis (rotation center) of the workpiece, and an even pressing force will work around the axis of the workpiece, preventing the workpiece from coming out of the mounting hole of the holder. They can unite their minds and chucking firmly. However, since the number of jaws is to prevent the work from slipping out of the mounting hole (movement in the axial direction), one may be sufficient.

Furthermore, at the end of the main body opposite to the mounting hole, notches of different depths are formed symmetrically with respect to the axis to form a cylindrical fitting part of the HSK standard. It is designed to fit into a cylindrical fixing jig that protrudes from the table of the processing machine, and a circumferential gripping groove is formed on the outer periphery of the main body, which has a mounting hole and jaws, to be gripped by the clamp unit exchange device of the machining center. Then, the main body is gripped by a clamp unit changing device such as a robot different from the clamp unit changing device through this gripping groove, and the main body is attached to the fixing jig and removed from the fixing jig. It can be done.

In this way, the mounting part of the workpiece is perfectly fitted into the mounting hole of the holder body, the axes of the holder body and the workpiece are aligned, and the workpiece is prevented from coming off from the mounting hole by pressing the jaws of the holder body. By doing so, the work holder for the processing machine can be replaced automatically. That is, it becomes possible to fully automate workpiece machining, and the efficiency of the machining work can be greatly improved.
Further, the work holder for a processing machine shown in each of the above configurations has good center positioning accuracy and is suitable for machining centers, lathes, multi-tasking machines, etc. with 4-axis or 5-axis control, where a workpiece is rotated and processed.
In other words, there are many benefits, especially in lathe processing and lathe-based multi-tasking machines, and if the center positioning accuracy is good, the runout accuracy of the workpiece will be increased. In addition, if the runout accuracy is good, centering work is not necessary, and the machining allowance in the radial direction of the workpiece can be reduced. If the removal allowance can be reduced, material processing costs can also be reduced.
Therefore, compared to a scroll chuck, it has a more compact shape, wastes less workpiece material, and provides strong clamping and rigidity by pressing against the reference end surface. In addition, in the case of a scroll chuck, it is necessary to replace the jaws of the chuck each time when the outer diameter of the workpiece differs, and centering is also necessary and time-consuming. You may have to remove it and replace it. In contrast, the present invention does not require the effort of replacing the fixing device on the machine side, and can be replaced and installed easily and with high precision even when processing a wide variety of workpieces of different sizes. Furthermore, automatic exchange is also possible.

This invention is constructed as described above, and the mounting part of the workpiece is perfectly fitted into the mounting hole of the holder, the axes of the holder and the workpiece are aligned, and centering is performed, and the jaws prevent the workpiece from coming off from the mounting hole. As a result, the workpiece is stably supported by the mounting hole, and good machining accuracy can be obtained.

A perspective view of a work holder for a processing machine and a work according to an embodiment of the present invention A partially cutaway front view showing the relationship between the fixing jig, holder, and workpiece of the processing machine of the same embodiment. A partially cutaway front view of the same embodiment with a workpiece attached to the holder

An embodiment of a work holder A for a processing machine according to the present invention is shown in FIGS. 1 to 3. This work holder A for a processing machine includes a holder main body 1 which is circular in plan view, a mounting hole 2 which is circular in plan view into which a mounting part (chucking part) 20 for a workpiece W on the upper surface of the holder main body 1 is fitted, and Four jaws 3, 3, 3, 3 for pushing the workpiece W are provided around the hole 2 at equal intervals in the circumferential direction. The clamp portion (pressing portion) 4 of each jaw 3 is formed with an inclined surface 5a having a surface normal that rises toward the mounting hole 2 side. The taper angle θ (see FIG. 2) of the inclined surface 5a with respect to the mounting hole 2 is, for example, 60 degrees. The bottom of the jaw 3 is fitted into a groove 6 formed in the holder body 1, and by sliding in the groove 6, it can freely move toward and away from the opposing jaw 3 (the center of the mounting hole 2). It has become.

A screw hole 7 is formed in the holder main body 1 inside the jaw 3 in the sliding direction thereof, and a bolt 8 inserted from the side surface of the jaw 3 is screwed into the screw hole 7. Therefore, as shown in FIGS. 2 and 3, by screwing the bolt 8, the jaws 3 move forward and backward toward the center of the mounting hole 2 (move toward and away from the opposing jaws 3). In the figure, 9 is a center hole.

The workpiece W can have various shapes such as a cylinder or a prism, but in this embodiment, the main body 21 is round bar-shaped, and the mounting surface (the left side in FIG. 2) of the main body 21 is provided with the mounting hole 2. A mounting portion (chuck portion) 20 for the workpiece W to be fitted is formed in advance. The mounting portion 20 consists of a thin cylindrical base 22 whose central axis is the rotation axis of the workpiece W, and a thin inverted truncated conical chuck portion 23 on the upper surface (lower surface) of which is coaxial. The mounting hole 2 side is an inclined surface 23a having a taper angle θ corresponding to the taper angle θ of the inclined surface 5a formed on the clamp portion 4.

Therefore, the tip of the clamp part 4 fits into the triangular groove formed by the chuck part 23 and the base part 22 of the workpiece W, and the workpiece W easily comes off from the clamp part 4 (jaw 3). There will be no. Moreover, when the two clamp parts 4, 4 are brought relatively close to each other and chucked so that the inclined surface 5a of the clamp part 4 and the inclined surface 23a of the workpiece W are brought into contact with each other, as shown in FIG. Due to this contact force, the workpiece W is pressed against the bottom surface 2a of the mounting hole 2 or the surface 2b of the holder body 1 around the mounting hole 2, and the workpiece W is reliably fixed to the mounting hole 2 (workpiece W is firmly attached to holder A (high mounting rigidity). The taper angle θ' of the inclined surface 23a of the workpiece W may be changed as appropriate to match the taper angle θ of the inclined surface 5a formed on each jaw 3, but it is difficult to easily machine the inclined surface 23a. Preferably, the angle is within the range of 45 to 60 degrees.

The outer circumferential surface of the base 22 is formed to fit snugly into the mounting hole 2 (the outer diameter of the base 22 and the inner diameter of the mounting hole 2 are almost the same (extremely small tolerance)) so that no looseness occurs. That is, the attachment hole 2 is formed into a circular shape in a plan view that is the same size as the attachment part 20 of the workpiece W, and when the attachment part 20 is perfectly fitted into the attachment hole 2, the circumferential surface 2c of the attachment hole 2 is aligned with the workpiece W. It serves as a reference plane in the radial direction and is used for centering.
Moreover, the height L ₁ of the base 22 and the height L ₂ of the chuck part 23 are such that when the mounting part 20 is fitted into the mounting hole 2, the bottom surface (left side surface in FIG. 3) 23b of the chuck part 23 is in the mounting hole 2. It is appropriately set so that the bottom surface 20a of the workpiece W around the base 22 contacts the surface 2b of the holder main body 1 around the mounting hole 2. The heights L ₁ and L ₂ are determined by the contact of the bottom surface of the chuck part 23 with the bottom surface 2a of the mounting hole 2, or the contact between the bottom surface 20a of the workpiece W around the base 22 and the surface 2b of the holder body 1 around the mounting hole 2. It can be set so that both types of contact are performed, or only one of them is performed. By this contact, the workpiece W is positioned in the axial direction on the holder A (the contact surface serves as an axial attachment reference surface for the workpiece W).

Note that when the attachment part 20 is formed on the work W, it is necessary to process it, but if the attachment part 20 is a thin cylindrical base 22 or a thin inverted truncated conical chuck part 23, lathe processing is possible. , there is less waste in the clamp part (attachment part 20) (the length of the material to be gripped by the chuck (jaws 3) can be significantly shortened). Particularly, the effect is high when the workpiece W is in the shape of a round bar.
In addition, with the attachment part 20, there is no need to replace the fixing device 14 of the holder A on the processing machine side regardless of the shape of the workpiece W, and even when machining a variety of products with different sizes of workpieces W, it is easy and It can be replaced and installed with high precision. Incidentally, with a scroll chuck, if the chucking part of the workpiece W differs in outer diameter, for example, the chuck jaws must be replaced each time, centering work is also required, and the mounting part The workability is poorer than the case with 20.

The end of the holder body 1 opposite to the mounting hole 2 is an HSK standard cylindrical fitting part with notches 13 of different depths formed symmetrically with respect to the axis, as shown in Figs. 3, the cylindrical fitting part having the notch part 13 is fitted into a cylindrical fixing jig 14 protruding from the table T of a processing machine such as a machining center. The work holder A is fixed (see FIG. 6 of Patent Document 1). In FIG. 2, 16 is an HSK clamp unit, and 17 is its cover.

Furthermore, a circumferential grip groove 15 is formed on the outer periphery of the main body 1 of the work holder A for a processing machine. By gripping the holder main body 1 through the gripping groove 15 with a clamp unit replacement device using a robot or the like, the holder A can be replaced automatically. That is, the processing of the workpiece W can be fully automated, and the efficiency of the processing operation can be greatly improved.

In addition, in this embodiment, from a design point of view, the portions in front of the gripping groove 15 (jaw 3, attachment hole 2, etc.) can be said to be a feature of the present invention. Therefore, the mounting standard (shank part) of the holder A on the table T of the processing machine is not limited to the HSK standard, but also various well-known standards such as the BT standard, CAT standard, DIN standard, CAPTO standard, and ISO standard. can be adopted.
Furthermore, in the embodiment, the number of jaws 3 is an even number such as four, and the clamp portions 4 are arranged to face each other, and each jaw 3 approaches and separates in the opposing directions. , 3, or 5, the respective jaws 3 can be provided so as to move toward and away from the center of rotation. In either case, if there are a plurality of jaws 3, they are spaced at equal intervals around the main body 1.
Note that the mechanism shown in the above embodiment for bringing the jaws 3 closer to each other is not limited to the one shown in FIG. Can be done.
In this way, the embodiments disclosed this time should be considered to be illustrative in all respects and not restrictive. The scope of this invention is indicated by the claims, and it is intended that all changes within the meaning and range equivalent to the claims are included.

A Work holder for processing machine W Work 1 Work holder body for processing machine 2 Mounting hole 3 Jaw 4 Clamp part (pressing part)
5a Inclined surface 6 Guide groove 8 Adjustment bolt 13 Notch 14 Fixing jig (fixing device)
15 Grasp groove

Claims (2)

There is a mounting hole (2) on the upper surface of the main body (1) into which the mounting part (20) of the workpiece (W) fits, and the workpiece (W) is placed around this mounting hole (2) toward the center of the mounting hole (2). A work holder for a processing machine, comprising a jaw (3) that presses with the
The mounting hole (2) is formed into a circular shape in a plan view with the same size as the mounting part (20) of the workpiece (W), and the mounting part (20) fits perfectly into the mounting hole (2), and the mounting hole ( The circumferential surface (2c) of 2) serves as the reference surface in the radial direction of the workpiece (W) for centering, and the bottom surface (2a) of the mounting hole (2) or the opening side edge of the mounting hole (2) The outer peripheral surface (2b) serves as the axial reference surface of the workpiece (W),
The pressing part (4) of the jaw (3) that presses the workpiece (W) is formed with an inclined surface (5a) having a surface normal that stands up toward the mounting hole (2). ) moves with respect to the mounting hole (2) by threaded connection with the adjustment bolt (8), and connects the inclined surface (5a) and the mounting portion (20) of the workpiece (W) with the inclined surface (5a). ) is in contact with an inclined surface (23a) formed to face the workpiece (W), and the workpiece (W) is pressed into the attachment hole (2) by this contact force ;
There are a plurality of jaws (3), and each jaw (3) is arranged so as to be able to move toward and away from the center of rotation,
The workpiece (W) is configured to hit at least one of the bottom surface (2a) of the attachment hole (2) or the outer peripheral surface (2b) of the main body (1), and A work holder for a processing machine, characterized in that an axial end face of the jaw (3) is located between each axial position of the surface (2b). The end of the main body (1) opposite to the mounting hole (2) has notches (13, 13) of different depths formed symmetrically with respect to the axis to form a cylindrical fitting according to the HSK standard. This cylindrical fitting part is adapted to fit into a cylindrical fixing jig (14) protruding from the table of the processing machine,
A circumferential gripping groove (15) is formed on the outer periphery of the main body (1) having the mounting hole (2) and the jaw (3), and the gripping groove (15) is gripped by a clamp unit replacement device of a machining center. The main body (1) is gripped by a clamp unit exchange device such as a robot via the clamp unit exchanger, and the main body (1) is attached to and removed from the fixing jig (14). The work holder for a processing machine according to claim 1 , characterized in that the work holder is configured as follows.

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