JPH0123683Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a device for attaching a cutting tool to a cutting machine, and in particular, it is a device for attaching a cutting tool to a cutting machine. This invention relates to an improvement of a tool mounting device.

In a cutting machine, it is desirable to mount the cutting tool in an accurate position and with sufficient rigidity. In response, the present applicant has devised a cutting tool mounting device that satisfies the above requirements while being as simple in structure as possible, inexpensive to manufacture, and easy to attach and detach, and has filed an application. .
This is Utility Model Registration Application No. 59168 of 1983.
This means that a fixing member that is fixed to the tool mounting part of a cutting machine and a tool holder that holds a cutting tool and is attached to and detached from the fixing member are attached to one side of each flat surface that is in close contact with each other. a trapezoidal groove that is open toward one plane thereof so as to form an angle of 2 degrees to 17 degrees with respect to each other, and a trapezoidal protrusion that has a tapered side plane corresponding to the trapezoid groove on the other side, and the fixing member The clamp shaft is movable in a direction perpendicular to the one plane and is held in a state in which one end protrudes from approximately the center of the trapezoidal groove or the trapezoidal protrusion, and the protruding end of the clamp shaft is configured to have a radially outward direction. an engagement head provided in the tool holder, which is engaged with an engagement groove formed in the tool holder that extends parallel to the trapezoidal groove and has at least one longitudinal end open; and a retraction mechanism for the clamp shaft. The dimensions of the trapezoidal groove and the trapezoidal protrusion are determined so that the tool holder and the fixing member not only come into close contact with each other on the one plane, but also tightly fit into the trapezoidal groove and the trapezoidal protrusion. It is characterized by this.

However, subsequent research revealed that there is still room for improvement. That is, because the shapes of the parts constituting the device are complex, many man-hours are required for processing, resulting in a high cost.

The present invention was developed against this background, and its purpose is to further simplify the clamping mechanism, thereby simplifying the part shape, reducing processing man-hours, and reducing costs. It is an object of the present invention to provide a cutting tool changing device which has extremely high tool mounting accuracy and rigidity, and can particularly quickly change cutting tools.

To achieve such an object, the present invention provides a cutting tool mounting device including the fixing member, tool holder, trapezoidal groove, trapezoidal protrusion, clamp shaft, engagement head, engagement groove, retraction mechanism, etc. , an elastic member is provided between the clamp shaft and the fixed member to constantly bias the clamp shaft in the projecting direction, and a retraction mechanism is (a) formed on the side surface of the clamp shaft in a direction perpendicular to the axis of the clamp shaft; a tapered hole with a circular cross section whose diameter decreases as it approaches its axis, and (b) a position offset from the center line of the tapered hole in the fixing member to the side opposite to the contact plane between the fixing member and the tool holder. and a tightening screw which is screwed into a threaded hole formed parallel to the tapered hole and has a conical surface with a taper equal to that of the tapered hole at its tip,
The clamp shaft is pulled in against the biasing force of the elastic member by engagement between the inner peripheral surface of the tapered hole and the conical surface.

With this configuration, it is possible to improve the positioning accuracy of the tool holder with respect to the fixing member, and also increase the mounting rigidity, especially the rigidity against rotational torque applied to the tool holder based on cutting resistance, and the clamp shaft. Remove the tool holder from the fixing member by loosening it slightly.
Alternatively, the effects of the invention related to the above-mentioned application, which are attachable and easy to attach and detach for tool replacement, can be obtained, and the following unique effects can also be obtained.

In other words, since the clamp shaft is always urged in the protruding direction by the elastic member, the retraction mechanism does not need to have a function of protruding the clamp shaft, and only needs to have a retraction function, resulting in a simple configuration. This makes it possible to reduce costs. Moreover, since the tapered hole and the tightening screw that constitute the retraction mechanism both have circular cross sections, they are easy to process, and the effect of further reducing costs can be obtained.

An embodiment of the present invention will be described in detail below with reference to the drawings.

1 and 2, reference numeral 10 denotes a fixing member, which is positioned by a parallel key 14 fixed with a bolt 12 and fixed to a tool holder 15 of the cutting machine, as shown in FIG. This fixing member 10 is provided with a clamp shaft hole 18 perpendicular to a mounting surface 16 serving as a contact plane, and a screw hole 20 penetrating through this hole 18 such that their axes intersect with each other. A clamp shaft 24 having an engaging head 22 formed at its tip is slidably fitted into the clamp shaft hole 18.
This engaging head 22 has a disk shape with both ends cut out parallel to each other. This engaging head 22 is engaged with an engaging groove 28 of a tool holder 26 attached to the fixing member 10.

In the clamp shaft hole 18, the fixing member 1 is inserted so as to close one opening of the clamp shaft 24.
A countersunk 34 as an elastic member is inserted between the presser plate 32 attached to the tool holder 2 and the clamp shaft 24, and the clamp shaft 24 is attached to the tool holder 2.
It is urged to protrude in the direction of 6. A through hole 36 is provided in the intermediate portion of the clamp shaft 24 in a direction perpendicular to the axis.
A tapered hole 38 is formed from one open end of the through hole 36, the diameter of which decreases as it approaches the axis. Note that the disc spring 34 may be an elastic member such as a coil spring or a leaf spring.

A tightening screw 40 is screwed into the screw hole 20 of the fixing member 10, and the tightening screw 40 has a tip portion 42 formed with a conical surface having a slope substantially equal to that of the tapered hole 38. Hexagon socket 44 for hex wrench
is formed. The conical surface of the tip 42 of the tightening screw 40 is connected to the clamp shaft 24 in the tapered hole 38.
The clamp shaft 24 is prevented from protruding by the disk spring 34, and the tightening screw 40 is rotated so that its tip When the position of the portion 40 changes in the axial direction, the protruding position of the clamp shaft 24 is changed according to the action of the conical surface of the tip portion and the tapered hole 38.
Further, the tightening screw 40 also serves to prevent the clamp shaft 24 from rotating. The smaller the taper angle of the tapered hole 38, the greater the force for pulling in the clamp shaft 24, but if it is too small, the necessary stroke will not be obtained. In this embodiment, this taper angle is set approximately in consideration of such circumstances.
It is said to be 40 degrees.

As shown in FIG. 1, the mounting surface 16 of the fixing member 10 facing the tool holder 26 has inner wall surfaces 46 on both sides opening toward the tool holder 26 so as to form an angle of 10 degrees with each other. A trapezoidal groove 48 is provided. This trapezoidal groove 48 extends in the longitudinal direction of the engaging head 22 of the clamp shaft 24.
In addition, the clamp shaft 24 is formed to be located approximately at the center of this trapezoidal groove 48.

A trapezoidal protrusion 52 that fits into the trapezoidal groove 48 is formed on the attachment surface 50 of the tool holder 26, which is a contact plane facing the fixing member 10.
An engagement groove 28 having a T-shaped cross section is provided in the center of the clamp shaft 24, into which the engagement head 22 of the clamp shaft 24 can engage. When the clamp shaft 24 is tightened in the retracting direction, not only the inclined surfaces 54 on both sides of the trapezoidal protrusion 52 are in close contact with the side wall surfaces 46 of the trapezoidal groove 48, but also the surface mounting surfaces 16 and 50 are in close contact with each other. It is configured so that

On the upper end surface of the tool holder 26, a block 56 is fixed at the upper end position of the trapezoidal protrusion 52.
A core height adjustment bolt 58 is provided at the end of the block 56 that projects toward the fixing member 10 so that it can be screwed out toward the fixing member 10. And the tool holder 26
As shown in FIG.
A cutting tool holder 64 to which a cutting tool (chip) 62 is fixed is screwed into the groove 60.

The cutting tool mounting device configured as above is
After fitting the tool holder 26 from above by engaging its engagement groove 28 and the engagement head 22 of the clamp shaft 24, and positioning it in the vertical direction with the center height adjustment bolt 58, use a hexagonal wrench. It can be quickly attached by rotating the tightening screw 40. That is, as for the installation procedure, first rotate the tightening screw 40 counterclockwise to loosen it, and then tighten the fixing member 1.
0 and the mounting surface of the tool holder 26,
After confirming that there are no chips or the like, the tool holder 26 is attached from above along the trapezoidal protrusion 52. Next, by removing the tightening screw 40 clockwise, the tightening screw 40 is advanced, and the tip portion 42 of the tightening screw 40 is moved forward.
When the clamp shaft 24 is retracted by the wedge action between the rear portion of the trapezoidal groove 48 and the rear portion of the tapered hole 38, both inner wall surfaces 46 of the trapezoidal groove 48 are brought into contact with both inclined surfaces 54 of the trapezoidal protrusion 52, and the inner Wall surface 46 and slope surface 54
Since they form a small inclination angle, a large wedge action is applied, and the inner wall surface 16 of the fixing member 10 is brought into close contact with the mounting surface 50 of the tool holder 26 with high pressure, resulting in extremely accurate positioning and It can be installed while maintaining high rigidity.

Next, as a removal procedure, the cutting tool 6
2. After cleaning the chips etc. adhering to the tool holder 26 etc., loosen the tightening screw 40 and move the trapezoidal protrusion 52 to the clamp shaft 24 according to the biasing force of the disc spring 34.
After protruding, the tool holder 26 can be pulled out upward.

Therefore, if a plurality of tool holders having the same structure are prepared, the time required for exchanging cutting tools and positioning them after attachment can be significantly reduced. That is, each tool holder can be attached to and removed from the fixing member 10 by simply rotating the tightening screw 40 in a predetermined direction, and each tool holder can be attached to the fixing member 1 while reliably satisfying the above conditions.
Since it is fixed at 0, there is no need to adjust the position after installation, and turning can be started immediately.

Although the most desirable embodiment of the present invention has been described above, the present invention is not limited to this embodiment in any way, and various improvements and modifications can be made without departing from the gist of the present invention. It can be implemented.

For example, the trapezoidal protrusion 52 may be provided on the fixing member 10 and the trapezoidal groove 48 may be provided on the tool holder 26. Also,
If the angle formed by the side walls 46 of the trapezoidal groove 48 is too large, it will be difficult to bring both the side walls 46 and the mounting surface 16 into close contact with the tool holder 26 at the same time; There is an appropriate range because the stiffness against In other words, if the angle is between 2 and 17 degrees, the objective can be achieved.

Furthermore, a compression coil spring, elastic rubber, or the like may be used instead of the disc spring 34 as the elastic member.

Further, although the above embodiment is a cutting tool mounting device in which the tool holder is fixed, the device of the present invention may be used in a boring bar type device in which the tool holder is rotated.

[Brief explanation of the drawing]

Fig. 1 is a top view of a tool mounting device which is an embodiment of the present invention, and Fig. 2 is a -
FIG. 10...Fixing member, 15...Tool holding part, 1
6, 50...Mounting surface, 22...Engagement head, 24...
... Clamp shaft, 26 ... Tool holder, 28
...Engagement groove, 34 ... Belleville spring (elastic member), 38
...Tapered hole, 40...Tightening screw.

Claims (1)

[Scope of Claim for Utility Model Registration] Any one of the planes of a fixing member fixed to a tool attachment part of a cutting machine and a tool holder that holds a cutting tool and is attached to and detached from the fixing member, which are in close contact with each other. On one side, a trapezoidal groove is provided that is open toward one plane so that both side wall surfaces form an angle of 2 degrees to 17 degrees with respect to each other, and on the other side, a trapezoidal protrusion having a tapered side surface corresponding to the trapezoidal groove is provided. In addition, the clamp shaft is held by the fixing member in a state where the clamp shaft is movable in a direction perpendicular to the one plane and one end protrudes from approximately the center of the trapezoidal groove or the trapezoidal protrusion, and the protruding end of the clamp shaft an engaging head provided facing outward in the radial direction is engaged with an engaging groove formed in the tool holder, extending parallel to the trapezoidal groove and having at least one longitudinal end open; When the clamp shaft is retracted by the retraction mechanism, the tool holder and the fixing member are not only brought into close contact with each other on the one plane, but also the trapezoidal groove and the trapezoidal projection are tightly fitted together. A cutting tool mounting device having determined dimensions, wherein an elastic member is provided between the clamp shaft and the fixing member to constantly bias the clamp shaft in the projecting direction, and the retraction mechanism is configured to: (a) (b) a tapered hole with a circular cross section that is formed on the side surface of the clamp shaft in a direction perpendicular to the axis of the clamp shaft and whose diameter decreases as it approaches the axis; A tightening screw is screwed into a threaded hole formed parallel to the tapered hole at a position offset to the opposite side from one plane, and has a conical surface with a taper equal to that of the tapered hole at the tip. A quick-exchangeable cutting tool mounting device, characterized in that the clamp shaft is pulled in against the biasing force of the elastic member by engagement between the inner circumferential surface of the tapered hole and the conical surface.