JP4185766B2 - Collet chuck and bar support device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a collet chuck and a bar support device using the collet chuck, and more particularly to a collet chuck and a bar support device that are attached to a main shaft of a lathe and are thin and light and capable of rotating at high speed.
[0002]
[Prior art]
An example of a bar support device provided with a collet chuck attached to a spindle or the like of a conventional lathe is described in, for example, Japanese Patent Application Laid-Open No. 9-108917. In this bar support device, the collet chuck is formed with three slits 24e in the axial direction as shown in FIG. 5, and the sleeve 25 is moved back and forth in the axial direction by air pressure to grip / release the workpiece W. It was like that.
[0003]
[Problems to be solved by the invention]
In recent years, there has been an increasing demand for high-speed turning of lathes in order to improve machining accuracy and shorten machining time. In addition, materials that are easily deformed, such as aluminum and brass, are increasing. However, in the above-described conventional collet chuck and bar support device, the end of the collet chuck moves in an arc shape and comes into contact with the workpiece, so that the gripping force is small and the workpiece is easily scratched. was there. Furthermore, there is a problem that the apparatus becomes thicker and heavier by the length of the collet chuck and is not suitable for high-speed rotation due to vibration caused by shaft shake.
An object of the present invention is to solve the above-mentioned problems of the prior art, and to provide a collet chuck that is thin, lightweight, and capable of rotating at high speed, and a bar material support device using the collet chuck.
[0004]
[Means for Solving the Problems]
The collet chuck of the present invention is formed by dividing one end of a substantially cylindrical chuck into an odd number, and is formed at the other end with a gripping portion of a workpiece having a tapered surface and a vertical surface perpendicular to the axis, and the other end. When the position of the gripping portion is regulated by the tapered surface and the vertical surface, the surface of the gripping portion that contacts the workpiece is an axis. And a thin plate-like member having elasticity so as to be parallel to each other.
[0005]
According to another aspect of the present invention, there is provided a bar material support device comprising: a collet chuck according to claim 1; a sleeve having a tapered surface in contact with the tapered surface of the collet chuck; a connecting member that connects the sleeve and the drive member; A cap having a vertical surface that covers a side surface of the end portion and is in contact with the vertical surface of the collet chuck is provided.
[0006]
According to the present invention, since the length of the collet chuck is shortened, the entire length of the bar support device can be shortened and lightened, and high-speed rotation is possible. Further, since the collet chuck is divided into nine equal parts, the gripping force is improved, the workpiece is not easily scratched, and the centripetal force acts on the workpiece, so that the grasping repeatability is improved and high speed rotation is possible.
[0007]
Further, the position of the gripping portion of the chuck is regulated / determined by the surfaces of the sleeve and the cap, and the gripping portion is in contact with the workpiece, so that the gripping force is improved and the workpiece is not easily scratched.
Further, the position of the sleeve or the like is regulated by the cap, and the cylinder connecting shaft and the shaft of the sleeve automatically coincide with each other, so that blurring is reduced and high speed rotation is possible.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail. FIG. 1 is a cross-sectional view showing a configuration of a bar support device using a collet chuck 12 of the present invention. FIG. 2 is a cross-sectional view showing a state in which the work piece is gripped by attaching the bar support device of the present invention to the headstock of a lathe.
The bar support device main body 10 has a cylindrical shape having a ring-shaped chuck fixing rib 29 inside and having a shaft 23 as a central axis. FIG. 3 is a plan view showing the configuration of the bar supporting device body 10 of the present invention. A back cover 16 is provided at the rear part of the main body 10, and the main body 10 is fixed to a headstock 25 of a lathe by bolts (not shown).
[0009]
A hole 31 through which the work 23 passes is provided in the center of the main body 10, and three holes 30 through which the three protrusions 35 of the sleeve pressing ring 14 pass and a collet fixing ring 18 are provided in the chuck fixing rib 29 of the main body 10. Three holes 32 for fixing with bolts (not shown) are provided. The main body 10 may use a hard aluminum material for weight reduction.
[0010]
A cap 11 is fixed to the front portion of the main body 10 with bolts 20. As the material, a SUS material subjected to ion nitriding treatment (surface treatment) is used. A chip intrusion prevention ring 17 is fixed inside the end of the cap, and an O-ring 22 is attached to the inside of the ring 17 to press the work 26 and prevent intrusion of chips and coolant. ing. The outer surface of the chip intrusion prevention ring 17 and the corresponding inner surface of the cap 11 are formed in a tapered surface having an angle of about 1 degree that extends rearward and does not fall off.
[0011]
The sleeve 13 has a cylindrical shape, and the inner surface is a tapered surface that abuts on the tapered surface 41 on the outer side of the collet chuck 12. The rear inner side surface 24 of the cap 11 is in contact with the outer side surface of the sleeve 13. As the sleeve 13 and the collet chuck material described later, SUJ2 material can be used.
[0012]
FIG. 4 is a plan view showing the configuration of the sleeve pressing ring 14 as seen from the front side. The three protrusions 35 of the sleeve pressing ring 14 are fixed to the sleeve 13 and the bolt 21 through three holes (30) provided in the chuck fixing rib 29 of the main body 10.
[0013]
FIG. 5 is a plan view showing the configuration of the end portion of the cylinder connecting shaft 15. The cylinder connecting shaft 15 is connected to a cylinder of a lathe device (not shown) and can be moved / pressurized forward or moved / released backward by an operator's operation. The end of the cylinder connecting shaft 15 has a ring shape with three protrusions 38, and the protrusions 38 are engaged with the three protrusions 35 of the sleeve pressing ring 14. Accordingly, the sleeve pressing ring 14 and the sleeve 13 are also forcibly moved in accordance with the movement of the cylinder connecting shaft 15.
[0014]
The three protrusions 38 at the end of the cylinder connection shaft 15 and the inner surfaces 37 of the three protrusions 35 of the sleeve pressing ring 14 that come into contact when the cylinder connection shaft 15 is pressed forward are both tapered with a conical shape. When the cylinder connecting shaft 15 is pressed forward, the cylinder connecting shaft 15, the sleeve pressing ring 14, and the central axis of the sleeve 13 are automatically aligned.
[0015]
Further, when the sleeve 13 is pressed forward, the outer surface and the inner surface of the sleeve 13 are in contact with the inner surface 24 of the cap 11 and the tapered surface of the collet chuck 12, respectively, so that the positions of the respective members are fixed. Even if it rotates at a high speed, the vibration due to the shake of the shafts of the collet chuck 12 and the sleeve 13 is reduced.
[0016]
FIG. 6 is a plan view showing the configuration of the collet chuck 12 of the present invention. FIG. 7 is a developed view showing the configuration of the collet chuck 12 of the present invention. FIG. 8 is a cross-sectional view showing the configuration of the collet chuck 12 of the present invention.
The collet chuck 12 has a substantially cylindrical shape, and the front portion is divided into nine equal parts by a slit 50 in a plane perpendicular to the axis. Thus, by dividing the chuck into odd numbers, a centripetal force is generated in the workpiece 26 when the chuck is tightened, and the shake is reduced, so that high-speed rotation is possible.
[0017]
On the inner side surface of the front portion of the collet chuck 12, a grip portion (contact surface) 40 that contacts the workpiece 26 is formed. The outer surface of the grip portion 40 forms a tapered side surface 41 having a conical side shape, and abuts against the tapered surface of the sleeve 13. Further, the ring-shaped end surface 42 perpendicular to the axis is in contact with the end surface of the cap 11.
In front of the collet chuck 12, a groove 45 for fitting the co-rotating ring 46 is provided. For example, when the collet chuck is replaced, the co-rotation ring 46 is attached to the groove 45 to close the chuck and the workpiece gripping portion 40 is subjected to correction processing such as cutting and polishing, so that the coaxiality is increased and repeated. Position accuracy and runout accuracy are improved. The ring 46 is removed when the workpiece is processed.
[0018]
The rear portion of the collet chuck 12 forms a chuck ring 44, and the chuck ring 44 and the nine gripping portions 40 are connected to each other by a curved thin plate-like connection portion 43. This connecting portion 43 has a weaker elasticity than before, such that when the position of the gripping portion is regulated by the tapered surface and the vertical surface, the surface 40 of the gripping portion that contacts the workpiece is parallel to the axis. In addition, although the example in which the connection part 43 has a substantially S-shaped cross section has been disclosed, any shape such as a U-shape, J-shape, or L-shape can be adopted as long as the desired elasticity can be obtained. It is.
[0019]
The chuck ring 44 at the rear of the collet chuck 12 is inserted / fixed to the collet fixing ring 18 without play. The collet fixing ring 18 is fixed to the chuck fixing rib 29 with a bolt (not shown).
When the sleeve 13 advances, the position of the gripping portion of the chuck 12 is regulated by the surface 41 in contact with the tapered surface of the sleeve 13 and the surface 42 in contact with the cap 11, so that the surface 40 in contact with the workpiece 26 is always parallel to the shaft 23. The gripping part moves. Therefore, the gripping part and the work 26 are always in contact with each other, the gripping force is improved, and scratches are difficult to be attached.
The collet chuck is replaced by the following procedure. First, the bolt of the cap 11 is removed, and the collet chuck 12 is pulled out. Then, a new collet chuck 12 is inserted. Next, correction processing such as cutting and polishing of the workpiece gripping portion 40 described above is performed as necessary. When the diameter of the workpiece is changed, the chip intrusion prevention ring 17 of the cap 11 is pushed out to the inside of the cap, and the chip intrusion prevention ring 17 of another diameter is inserted from the inside of the cap.
[0020]
As mentioned above, although the Example of this invention was disclosed, the following modifications can also be considered to this invention. In the embodiment, the example in which the surface where the cap 11 and the chuck 12 contact is a plane perpendicular to the axis is disclosed, but this surface may be a tapered surface similar to that between the chuck and the sleeve. However, the inclination direction of the surface is the reverse direction.
[0021]
【The invention's effect】
As described above, according to the present invention, since the length of the collet chuck is shortened, there is an effect that the entire length of the bar support device can be shortened and reduced in weight and can be rotated at high speed. . In addition, since the collet chuck pawl is divided into an odd number of nine, the gripping force is improved, the work is not easily scratched, and the centripetal force acts on the work, so that the repeatability of grasping is improved and high-speed rotation is possible. . Furthermore, since the position of the gripping portion of the chuck is regulated / determined by the surfaces of the sleeve and the cap and the gripping portion is in contact with the workpiece, the gripping force is also improved, and there is an effect that the workpiece is hardly scratched.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a configuration of a bar support device using a collet chuck 12 of the present invention.
FIG. 2 is a cross-sectional view showing a state in which the work piece is gripped by attaching the bar support device of the present invention to a head stock of a lathe.
FIG. 3 is a plan view showing a configuration of a bar support device body 10 of the present invention.
4 is a plan view showing the configuration of a sleeve pressing ring 14 as seen from the front side. FIG.
5 is a plan view showing a configuration of an end portion of a cylinder connecting shaft 15. FIG.
FIG. 6 is a plan view showing the configuration of the collet chuck 12 of the present invention.
FIG. 7 is a development view showing the configuration of the collet chuck 12 of the present invention.
FIG. 8 is a cross-sectional view showing the configuration of the collet chuck 12 of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Bar material support apparatus main body, 11 ... Cap, 12 ... Collet chuck, 13 ... Sleeve, 14 ... Sleeve pressing ring, 15 ... Cylinder connecting shaft, 16 ... Back cover, 17 ... Chip entry prevention ring, 18 ... Collet fixation Ring, 19 ... chuck fixing rib, 20, 21 ... bolt, 22 ... O-ring, 23 ... shaft, 25 ... spindle head of lathe, 26 ... work, 41 ... taper surface

Claims (2)

A cylindrical main body having a collet chuck fixing rib having a ring shape inside and a plurality of holes provided therein;
A cap fixed to the front portion of the main body, covering the end side surface of the sleeve, the rear inner side surface being in contact with the outer side surface of the sleeve, and a cap provided with a vertical surface contacting the vertical surface of the collet chuck at the rear portion;
A cylindrical sleeve with a tapered surface on the inside that contacts the tapered surface of the collet chuck;
Is formed by equally dividing one end of the collet chuck substantially cylindrical odd a plane passing through the axis, provided with a tapered surface contacting the tapered surface of the sleeve on the outside, the shaft in contact with the vertical surface of the cap in front of the end face A workpiece gripping portion having a vertical surface perpendicular to the workpiece, a ring-shaped member formed on the other end of the collet chuck and fixed to the collet chuck fixing rib of the main body , the gripping portion and the ring-shaped member And a thin plate-like member having elasticity such that the surface of the gripping part that contacts the workpiece is parallel to the axis when the position of the gripping part is regulated by the tapered surface and the vertical surface. A collet chuck formed integrally ,
A sleeve pressing ring having a plurality of protrusions for fixing to the sleeve through a plurality of holes in the collet chuck fixing rib of the main body, and a pressing surface pressed by a cylinder connecting shaft of a lathe is formed in a taper shape; A bar support device comprising: a bar support device . 2. The bar support device according to claim 1, wherein the plate-like member of the collet chuck has a curved cross section including a shaft.

Images