JPH04101711A - Milling cutter installing device - Google Patents

Abstract

PURPOSE:To enhance installation accuracy of a milling cutter by drawing a connected cylindrical body, in which a polygonal bolt is screwed into a threaded hole for the polygonal bolt, into a fitting hole of a rotary main spindle, in a milling cutter installing device where the milling cutter is retained at the end of a main spindle of a milling machine. CONSTITUTION:In this device, a connected cylindrical body 2 of a cutter arbor 1, in which a polygonal bolt 4 is screwed into a threaded hole 3 for the polygonal bolt 4, is inserted into a fitting hole 10 provided at an end part of a rotary main spindle 9 of a milling machine so that a rotary main spindle abutting face 8 of the arbor 1 is brought into surface contact with an end face of the main spindle 9. After the insertion of the connected cylindrical body 2 is completed, an arbor drawing bolt 14 inserted through a hollow part 15 of the spindle 9 is screwed into the bolt 4 so as to strongly draw the connected body 2 into the fitting hole 10 of the main spindle 9. According to this action, tensile force of the bolt 14 is converted to expanding force for expanding respective apex portions of the bolt 4 outward. This expanding force expands and deforms the connected body 2 and the expanded portions are respectively brought into close contact with an inside circumferential surface of the fitting hole 10. At the same time, the face 8 of the arbor 1 is brought into tight contact with the end face of the main spindle 9.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an improvement in a milling cutter attachment device that is attached to the main shaft end of a milling machine and holds a milling cutter.

(Prior Art) Conventionally, this type of device is known to have a convex portion that fits into a recess provided at the end of the main shaft of a milling machine, and a flange portion that can be screwed to the end of the main shaft.

Further, as another conventional device, one is known that has a taper that fits into a tapered hole provided at the end of the main shaft of a milling machine, and is secured with a draw bolt from the rear end of the main shaft.

(Problem to be Solved by the Invention) However, since the concave portion provided at the former spindle end and the corresponding convex portion are made to fit together without any gaps, it is difficult to attach the former to the spindle end. In the case where the mounting is automatically performed by a robot, there is a problem in that it is difficult to attach the layer.

In addition, with the latter, it is difficult to process the taper hole provided at the end of the spindle and the corresponding taper, and if the machining accuracy of these is low, a gap will be created between the two, resulting in less accurate installation. The present invention aims to eliminate these problems.

(Means for Solving the Problems) In order to achieve the above object, the present invention was configured as follows.

That is, the present invention provides a connecting cylindrical body having a polygonal bolt threading hole and a rotary main shaft abutting surface on a milling cutter, and a connecting cylindrical body in which a polygonal bolt is threaded into the polygonal bolt threading hole.
The arbor draw-in bolt inserted from the hollow part of the rotating main shaft is inserted into the mounting hole provided at the end of the rotating main shaft to bring the rotating main shaft contact surface into surface contact with the end surface of the rotating main shaft, and the polygonal bolt is inserted into the polygonal bolt. The connecting cylinder is then pulled into the mounting hole of the rotating main shaft.

(Function) In the present invention configured as described above, the connecting cylinder of the milling arbor, in which the polygonal bolt is screwed into the polygonal bolt threading hole, is inserted into the mounting hole provided at the end of the rotating main shaft of the milling machine, and the milling arbor is attached to the milling arbor. The rotating spindle contact surface and the end surface of the rotating spindle are brought into surface contact.

When the insertion of the connecting cylinder is completed, the aperture drawing bolt inserted from the hollow part of the rotating main shaft is screwed onto the polygonal bolt, and the connecting cylinder is strongly pulled into the mounting hole of the rotating main shaft.

This converts the tensile force of the arbor draw bolt into an expansion force that outwardly expands each top of the polygonal bolt.

This expanding force expands and deforms the connecting cylinder integral with the polygonal bolt outwardly at a plurality of locations, and each of the expanded portions comes into close contact with the inner candle surface of the attachment hole of the rotating main shaft. At the same time, the rotating main shaft abutting surface of the milling arbor and the rotating main shaft end surface come into firm surface contact.

Therefore, the rigidity of the milling arbor relative to the rotating main shaft is extremely high, and the mounting accuracy is improved.

(Example) Embodiments of the present invention will be described with reference to the drawings.

In the figure, l is a milling arbor to which a milling cutter is attached, and a connecting cylinder 2 having a polygonal bolt screw hole 3 is provided at the rear thereof. Then, the polygonal bolt 4 is screwed into the polygonal bolt-type entrance hole 3.

The polygonal bolt 4 is preferably a triangular prism with threads 5 formed only at the tops thereof, as shown in FIG. Note that the polygonal bolt 4 may be a polygonal prism such as a square prism instead of a triangular prism, with external threads formed only at the tops of each polygonal prism.

The polygonal bolt 4 is provided with a screw hole 7 into which the locking rod 6 of No. 3 (1) is screwed, and the tip of each locking rod 6 screwed into the screw hole 7 is connected to the bottom of the inner circumference of the connecting cylinder 2. Insert each into the holes drilled in the.

The connecting cylinder 2 of the milling arbor 1 with the polygonal bolt 4 screwed thereon is inserted into the mounting hole 10 drilled at the front end of the rotating main shaft 9 of the milling machine, and the rotating main shaft abutting surface 8 provided on the milling arbor 1 is inserted into the mounting hole 10 bored at the front end of the rotating main shaft 9 of the milling machine. is brought into surface contact with the end face of the rotating main shaft 9.

One key piece 12A of the cross key 12 fits into the notch 11 formed by cutting out the left and right sides of the open end of the connecting cylinder 2 inserted into the mounting hole 10. cross key 1
The other key piece 12B of No. 2 is fitted in advance into a fitting groove 13 provided at the bottom of the mounting hole IO.

The rotating main shaft 9 is provided with a hollow part 15 into which an arbor draw-in bolt 14 is inserted, which pulls the connecting cylinder 2 of the milling arbor 1 into the mounting hole IO of the rotating main shaft 9 and fixes it therein. This arbor draw-in bolt 14 is made of a hexagon socket head bolt. After the arbor drawing bolt 14 with the washer 16 inserted passes through the through hole 17 of the cross key 12, its tip is screwed into the threaded hole 18 of the polygonal bolt 4, thereby connecting the connecting cylinder 2 of the milling arbor l. Strongly pull it into the mounting hole 10 of the rotating main shaft 9.

Next, an example of use of the present invention configured as described above will be described.

First, after screwing the polygonal bolt 4 into the polygonal bolt screw insertion hole 3 of the milling arbor L, the rotation stopper rod 6 is inserted into the polygonal bolt 4.
and insert the tips of each of the rotation stopper rods 6 into the corresponding through holes of the 7 rice arbor l.

Next, the connecting cylinder 2 of the milling arbor l is inserted into the mounting hole lO of the rotating main shaft 9, and the rotating main shaft end face 8 of the milling arbor l is
is brought into surface contact with the end face of the rotating main shaft 9.

After that, the 7-bar draw bolt 1 is inserted into the hollow part 15 of the main shaft 9 for one rotation.
4, the arbor draw-in bolt 14 is passed through the through hole 17 of the cross key 12, and its tip is screwed into the threaded hole 18 of the polygonal bolt 4. Pull firmly into the mounting hole.

Then, the milling arbor 1 by the arbor drawing bolt 14
When the retraction is completed, the tensile force of the arbor retraction bolt 14 causes an expansion force F that expands each top of the polygonal bolt 4 outward.
(see Figure 3).

Due to this expansion force F, the polygonal bolt 4 is integrally connected to the connecting cylindrical body 2.
The three locations are also expanded outward and deformed, and each of the expanded portions is brought into close contact with the inner circumferential surface of the attachment hole 10 of the rotating main shaft 9. At the same time, the rotating main shaft contact surface 8 of the milling cutter l and the rotating main shaft 9
makes strong surface contact with the end face of the

Therefore, the rigidity of the milling arbor l relative to the main shaft 9 for one rotation becomes extremely large.

After sowing, attach the milling cutter to the milling cutter.

(Effects of the Invention) As described above, in the present invention, the milling arbor is provided with a connecting cylinder having a polygonal bolt screw hole and a rotating main shaft contact surface,
Insert the connecting cylinder with the polygonal bolt screwed into the polygonal bolt screw hole into the mounting hole provided at the end of the rotating spindle to bring the rotating spindle contact surface into surface contact with the end surface of the rotating spindle, and then pull in the arbor and tighten the polygonal bolt. Since the connecting cylinder is screwed onto the bolt and pulled into the mounting hole of the rotating main shaft, the rigidity of the milling arbor is improved and the mounting accuracy thereof is improved.

Furthermore, in the present invention, the milling arbor is attached to the rotating spindle by expanding and deforming the connecting cylindrical body within the mounting hole of the rotating spindle, so that the connecting cylindrical body of the milling arbor can be constructed loosely with respect to the mounting hole. This makes it easier to attach the milling arbor by inserting the connecting cylinder into the attachment hole, and is particularly suitable for realizing automation.

Furthermore, since the present invention does not require taper processing, the overall manufacturing work is easy.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view of an embodiment of the present invention, Fig. 2 is a front view of a polygonal bolt, Fig. 3 is a cross-sectional view of main parts of an embodiment of the present invention, and Fig. 4 is a longitudinal cross-sectional view of an embodiment of the present invention.
The figure is a diagram showing a deformed state of the connecting cylinder. 1... Milling arbor, 2... Connecting cylinder. 3... Polygonal bolt screw hole, 4... Polygonal bolt, 6.
・・Rotating stopper rod, 8・Rotating main shaft contact surface, 9・・・・
Rotating main shaft, 10... Mounting hole, 14... Arbor pull-in bolt, 15... Hollow part. Figure 2 Figure 3 Patent applicant Ariyoshi Kiko Group Agent Tobe Maki (3 others) Figure 4

Claims (1)

[Claims] A connecting cylinder having a polygonal bolt threading hole and a rotating spindle contact surface are provided in the milling arbor, and the connecting cylinder with the polygonal bolt screwed into the polygonal bolt threading hole is provided in an attachment hole provided at the end of the rotating spindle. the rotary main shaft contact surface and the rotary main shaft end surface are brought into surface contact, and an arbor drawing bolt inserted from the hollow part of the rotary main shaft is screwed onto the polygonal bolt to connect the connecting cylinder to the rotary main shaft. A milling cutter mounting device that retracts into the mounting hole.