Chucks or sockets – Socket type – Spring biased jaws
Patent
1995-05-01
1997-04-22
Bishop, Steven C.
Chucks or sockets
Socket type
Spring biased jaws
279 53, 409234, B23B 3120
Patent
active
056223730
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to a chucking device, and more particularly to a chucking device for holding a cutting tool such as a drill, an end mill or the like.
BACKGROUND ART
Generally, a cutting tool such as a drill, an end mill or the like is fitted to a rotation spindle of a machine tool by using a chucking device. FIG. 14 shows by way of example a conventional chucking device of the foregoing type, and the chucking device 1 consists of a main body 2, a cylindrical press-fitting member 3 and a tightening ring 4. A plurality of male threads 6a are formed on the outer peripheral surface of a fore end part 5 of the chucking device 1, and a tapered hole 6b whose inner diameter is enlarged toward the foremost end thereof is formed inside of the fore end part 5.
A tapered portion 3a capable of being fitted to the tapered hole 6b is formed on the outer peripheral surface of the press-fitting portion 3. On the other hand, a hole 3b adapted to be fitted onto a shank of a cutting tool 7 is formed on the inner peripheral surface of the press-fitting portion 3.
A plurality of female threads 8 capable of being threadably engaged with the male threads 6a of the chucking device 1 are formed on the inner peripheral surface of the tightening ring 4, and a plurality of balls 9 are disposed on a fitting surface to the press-fitting member 3.
With the chucking device 1 constructed in the above-described manner, when the tightening ring 4 is rotated in the tightening direction, the press-fitting member 3 is displaced in the P arrow-marked direction so that the outer peripheral surface of the press-fitting portion 3 is thrusted against the tapered hole 6b of the chucking device by the wedging action, causing the diameter of the press-fitting portion to be reduced, whereby the inner peripheral surface 3b of the press-fitting portion 3 firmly holds a shank of the cutting tool 7 in the tightened state.
With the conventional chucking device 1 as mentioned above, however, since the foremost end part of the press-fitting portion 3 is offset from the inside tapered surface of the main body 2, the offset part of the press-fitting member 3 does not sufficiently exhibit the wedging effect, resulting in a magnitude of tightening force effective for the cutting tool 7 becoming short. Thus, there arises a problem that the cutting tool is vibratively displaced during a cutting operation.
Therefore, an object of the present invention is to provide a chucking device which assures that a shank portion of a cutting tool can firmly be held in the tightened state over the whole range of a press-fitting member.
SUMMARY OF THE INVENTION
Specifically, according to the present invention, a chucking device is characterized in that it comprises a holder capable of being fitted into a rotation shaft of a machine tool; chucking barrel including on the connection surface side a plurality of axially extending projections located in the equally spaced relationship as viewed in the circumferential direction, a plurality of opening portions each formed between adjacent projections and a tapered hole formed therein; an axially displaceable driving annular member having a plurality of radially extending tooth-like projections formed to be fitted into the opening portions of the chucking barrel and having a plurality of male threads formed on the outer peripheral surface thereof; a tightening ring having a plurality of female threads threadably engageable with the male threads of the driving annular member formed on the inner hole surface thereof, the tightening ring being rotatably held on the outer peripheral surface of the chucking barrel; and a press-fitting member fixedly secured to the driving annular member and adapted to be fitted into the tapered hole of the chucking barrel.
It is preferable that the press-fitting member has a plurality of slits formed through the peripheral wall thereof so as to allow it to have flexibility.
A plurality of axially extending grooves are formed on the inner peripheral surface of the chucking
REFERENCES:
patent: 3685845 (1972-08-01), Fischer et al.
patent: 4865336 (1989-09-01), Keritsis
patent: 5123663 (1992-06-01), Mizoguchi
LandOfFree
Chucking device does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Chucking device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Chucking device will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-337822