JP2579799Y2 - Mounting device for annular cutter - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an apparatus for making a hole in a metal material such as a steel plate by using an annular cutter, and an apparatus for attaching an annular cutter to a cutter holder on a driving source side so as to be detachably attached. It is about.

[0002]

2. Description of the Related Art As an apparatus for mounting an annular cutter of this kind, for example, a tip end of a cutter holder connected to a driving source side and elastically holding a center pin on an axis line is capable of freely protruding and retracting in and out in the radial direction. In addition to providing a ball, a sleeve urged in the cutter holder tip direction by a spring is provided outside the tip portion of the cutter holder, and the sleeve holds the ball in a protruding state inside the cutter holder. In some cases, a concave portion is provided at the base end portion of the annular cutter fitted inside the distal end portion of the cutter holder, in which the ball protruding inside the cutter holder is engaged.

[0003] In this mounting device for an annular cutter, by sliding the sleeve toward the base end of the cutter holder against the spring, the ball is in a free state and the annular cutter can be attached and detached. Such a mounting device for an annular cutter is disclosed, for example, in Japanese Patent Application Laid-Open No. Sho 62-74515.

[0004]

However, in the above-mentioned conventional apparatus for mounting an annular cutter, the sleeve must be operated both when the annular cutter is mounted and when the annular cutter is removed. There is a problem, and solving such a problem has been a problem in improving the function.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and has as its object to provide an apparatus for mounting an annular cutter capable of improving the operability of attaching and detaching an annular cutter to and from a cutter holder. .

[0006]

According to the present invention, there is provided an apparatus for mounting an annular cutter according to the present invention, wherein a coupling member for an annular cutter is provided at a lower end of a cutter holder, and the coupling member includes an engaging portion for suppressing rotation of the annular cutter, A restraining ball which engages with a locking portion provided on the inner periphery of the annular cutter to prevent the annular cutter from separating in the axial direction; and a taper which is resiliently spring-loaded and presses the restraining ball outward in the connecting member. A ball retainer, and a center pin that is resiliently spring-loaded and whose tip projects from the lower end of the annular cutter. The center pin is provided with a small-diameter portion, and the annular cutter is mounted on the connecting member. The inner peripheral taper surface presses the restraining ball inwardly of the connecting member so that the restraining ball temporarily waits at the small diameter portion of the center pin to enable the annular cutter to be mounted. Cage, and the configuration with a means for solving the conventional problems.

[0007]

In the apparatus for mounting an annular cutter according to the present invention, in the cutter holder, the restraining ball is always urged to the outside of the connecting member by the ball presser repelled by a spring, and the connecting member is connected. Since the center pin on the inner side of the member is provided with a narrowed diameter portion corresponding to the amount of protrusion of the restraining ball, it is possible to immerse the restraining ball inside the connecting member by an external force.

Therefore, the restraining ball is engaged with the locking portion of the annular cutter by mounting the annular cutter on the connecting member while pressing the restraining ball inwardly of the connecting member on the inner peripheral tapered surface of the annular cutter. In this state, the attachment of the annular cutter is completed, and the annular cutter can be removed in such a manner that the annular cutter is pulled out against the urging force applied to the restraining ball.

Further, in the above-described apparatus for mounting the annular cutter, during drilling, the center pin is displaced in the axial direction with respect to the cutter holder and the annular cutter, and the position of the small diameter portion and the restraining ball are displaced. Movement of the connecting ball to the inside of the connecting member is prevented,
The engagement between the restraining ball and the locking portion of the annular cutter is maintained.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

A cutter holder 1 shown in FIGS. 1 and 2
Is formed of a cylindrical member opened downward, and a substantially cylindrical connecting member 3 fitted inside the annular cutter 2 is fixed to the inside of the lower end by screw connection. The side is connected to a rotary drive source (not shown).

The cutter holder 1 has a center pin 4 having a pointed lower end protruding from the lower end of the annular cutter 2 and a spring 5 for urging the center pin 4 downward.
Is inserted. The center pin 4 has a flange 4a near the upper end, and has a small diameter portion 4b narrowed slightly above the intermediate portion, and the flange 4a is applied to a stop ring 6 fixed inside the connecting member 3. The contact causes the downward movement to be restricted, and in this state, about half of the lower side protrudes from the connecting member 3.

The connecting member 3 is formed with a ball mounting hole 3a which opens laterally at a height corresponding to the small diameter portion 4b of the center pin 4 located inside the connecting member 3. Means that the restraining ball 7 is
Are provided so as to be freely protruded and retracted in and out in the radial direction. The ball mounting hole 3a is formed in a circular shape having a size smaller than the diameter of the restraining ball 7 outside the connecting member 3, so that the restraining ball 7 does not fall outside.

Further, a tapered ball press 8 for pressing the restraining ball 7 outward is provided in the connecting member 3. The ball presser 8 has a ring shape in which the center pin 4 penetrates at the center, and a contact portion with the restraining ball 7 has a downward tapered surface. , And is elastically held in a state of being pressed against the restraining ball 7.

On the other hand, the annular cutter 2 has a mounting portion 2a connected to the upper end thereof, and has a substantially cylindrical shape as a whole. A peripheral taper surface 2c is provided, and a concave locking portion 2b is provided for engaging a restraining ball 7 protruding outside the connecting member 3. The locking portion 2b has an inclined surface on the upper and lower sides, has a cross-sectional shape expanding toward the opening side, and is formed in a groove shape in the circumferential direction of the mounting portion 2a. Further, as shown in FIG. 1 (c), the fitting portion between the engagement portion 3b for preventing rotation provided at the lower end portion of the connecting member 3 and the mounting portion 2a has a radial cross section, particularly as shown in FIG. It is square.

Incidentally, in addition to the above configuration, the cutter holder 1
Is connected to a cutting oil supply system communicating with the inside thereof, and the center pin 4 is provided with a groove or the like for cutting oil circulation.

In the apparatus for mounting the annular cutter 2 having the above configuration, in the state before mounting shown in FIG.
The restraining ball 7 is always urged to the outside of the connecting member 3 by the spring 9 and the ball presser 8, and is constricted by the center pin 4 inside the connecting member 3 according to the amount of protrusion of the restraining ball 7. Since the small diameter portion 4b is provided, the restraining ball 7 can be immersed in the connecting member 3 by an external force.

Accordingly, when the mounting portion 2a of the annular cutter 2 is assembled to the connecting member 3 of the cutter holder 1, as shown in FIG. 2 (a), the inner peripheral tapered surface 2c of the mounting portion 2a
The restraining ball 7 pressed in the step enters the connecting member 3 and temporarily waits in the small-diameter portion 4b. Finally, as shown in FIG. Engages with the locking portion 2b of the mounting portion 2a to prevent the annular cutter 2 from separating in the axial direction. That is, the fitting of the annular cutter 2 is completed only by fitting the mounting portion 2a of the annular cutter 2 to the connecting member 3 against the urging force applied to the restraining ball 7.

At this time, in the mounting device, the fitting portion between the engaging portion 3b of the connecting member 3 and the mounting portion 2a of the annular cutter 1 has a hexagonal shape, and the locking portion 2b is the mounting portion. Since the mounting portion 2a is formed in the circumferential direction of the mounting member 2a, there are six fitting positions of the mounting portion 2a to the connecting member 3 corresponding to the number of corners, and the restraining ball 7 and the locking portion 2b are provided at any position. Are engaged, and the positioning of the annular cutter 2 is easy.

The annular cutter 2 is detached from the cutter holder 1 in such a manner as to be pulled out against the urging force applied to the restraining ball 7. As described above, in the mounting device, the annular cutter 2 can be attached and detached with one hand.

Further, in the above-described apparatus for mounting the annular cutter 2, the center pin 4 moves upward with respect to the descending cutter holder 1 and the annular cutter 2 due to the contact with the workpiece W during the drilling shown in FIG. And the position of the small-diameter portion 4b and the restraining ball 7 are shifted, so that the center pin 4 prevents the restraining ball 7 from moving inward of the connecting member, and the locking portion between the restraining ball 7 and the mounting portion 2a. 2b
Is maintained in the engaged state. Therefore, when the cutter holder 1 is raised after the drilling is completed, the annular cutter 2 does not come off from the cutter holder 1. After the completion of the drilling, the center pin 4 moves downward by the repulsive force of the spring 5, whereby the scrap S in the annular cutter 2 is pushed out as shown by the phantom line in FIG.

[0022]

As described above, according to the annular cutter mounting apparatus according to the first aspect of the present invention, the annular cutter can be easily attached to and detached from the cutter holder with one hand, and furthermore, the drilling is performed. In this case, an excellent effect is obtained in that the fixed state of the annular cutter can be maintained.

[Brief description of the drawings]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view illustrating an embodiment of the present invention in a state where an annular cutter is attached, FIG. 1A is a cross-sectional view taken along line AA in FIG. It is sectional drawing (c) based on the BB line arrow.

FIGS. 2A and 2B are a cross-sectional view of a main part illustrating a state where the cutter holder and the annular cutter are being fitted, and a cross-sectional view of the state where the annular cutter is removed;

FIG. 3 is a cross-sectional view of a main part illustrating a state during drilling.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cutter holder 2 Annular cutter 2b Locking part 2c Inner peripheral taper surface 3 Connecting member 3b Engaging part 4 Center pin 4b Small diameter part 5, 9 Spring 7 Restriction ball 8 Ball press

Claims (1)

(57) [Scope of request for utility model registration] 1. A connecting member for an annular cutter is provided at a lower end of a cutter holder. The connecting member engages with an engaging portion for suppressing rotation of the annular cutter and an engaging portion provided on an inner periphery of the annular cutter. A restraining ball for preventing the annular cutter from detaching in the axial direction, a ball presser with a spring which is resiliently pressed and presses the constraining ball outwardly of the connecting member, and a resiliently resilient spring having a ring-shaped tip. A center pin protruding from the lower end of the cutter is disposed, and the center pin is provided with a small diameter portion. When the annular cutter is mounted on the connecting member, the restraining ball is inwardly directed toward the connecting member by the inner peripheral taper surface of the annular cutter. An annular cutter mounting device characterized in that the annular ball cutter is mounted by pressing to temporarily hold the restraining ball at the small diameter portion of the center pin so that the annular cutter can be mounted.