JPH035363Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a hydraulic chuck device used for gripping objects to be held such as workpieces and tools in machine tools and the like.

[Prior art] In this type of conventional hydraulic chuck device,
To grip the object to be held, such as a workpiece or tool,
For example, as shown in Japanese Patent Publication No. 45-29346 and Japanese Patent Publication No. 47-5198, screws are generally tightened manually, which requires considerable time and effort to attach and detach the held object. The disadvantage is that it requires Due to the low work efficiency of conventional hydraulic chuck devices, despite having the advantage of high deflection accuracy when gripping objects, as a basic chuck, objects to be held are replaced one after another. For example, it is difficult to use in a special purpose machine or in a tool presetting device for a straight adapter holding a tool.

[Purpose of the invention] The purpose of the invention is to improve the above-mentioned problems.
It is an object of the present invention to provide a hydraulic chuck device with high work efficiency that enables automatic tightening and loosening operations of a held body.

[Summary of the invention] The gist of the invention to achieve the above objectives is as follows:
A sleeve that is easily elastically deformable for gripping a held object is attached to the rear end of the chuck body, the front end of which is attached to the main shaft of the machine, and an expansion is formed between the sleeve and the chuck body. An oil passage leading to the chamber is formed on the same axis as a pull stud attached to the front end of the chuck body, a piston rod is inserted into a through hole formed in the axis of the pull stud, and one end of the piston rod is used as a projecting end. The pull stud protrudes outward from an end face thereof, the other end is connected to a piston inserted into the oil passage, and the protruding end is pushed inward to pressurize the oil in the expansion chamber via the piston. , a hydraulic chuck device characterized in that the sleeve bulges toward the held object.

[Embodiments of the invention] The invention will be described in detail based on illustrated embodiments.

FIG. 1 is a longitudinal cross-sectional view of the first embodiment, and FIG. 2 is a cross-sectional view taken along the - line in FIG. 1. This first embodiment exemplifies a case in which the object to be held T is gripped from the outside, and the chuck body 1 has a tapered shank portion 2 at the front end for attachment to the main shaft S of the machine, and a tapered shank portion 2 at the intermediate portion. It has a flange 3 at the rear end thereof, and a cylindrical portion 4 at the rear end, and the cylindrical portion 4 is provided with an opening 5 that opens toward the axial direction. An oil passage 6 is provided in the axial direction from the front end,
This oil passage 6 is bent in the middle to become an oil passage 6a, and an opening is provided on the rear end surface of the chuck body 1 for replenishing and draining oil, and this opening is pushed by a set screw 7. It is closed by ball 8. A shunt 6b branched from the middle of the oil passage 6a is opened on the inner surface of the opening 5.

Furthermore, a pull stud 9 is attached to the taper shank portion 2.
A through hole 10 facing in the axial direction is bored in the center of the pull stud 9, and a piston 11 is inserted into the through hole 10 and into the oil passage 6 following it.
is inserted. The piston 11 is connected to a piston rod 13 via a ball 12. The piston rod 13 has a flange 14 in the middle,
Movement in the axial direction is restricted at a predetermined position by a counterbore 15 of the pull stud 9, and in this state, the piston rod 13 has a length such that its tip protrudes outward from the tip of the pull stud 9.

A thin cylindrical sleeve 16 is fitted into the opening 5, and the outer circumferential portion 17 of this sleeve 16 in the axial direction is further thinned to facilitate inward elastic deformation and to prevent the opening from forming. An annular expansion chamber 18 is formed between the inner surface of the tube 5 and the inner surface of the tube 5. A shunt 6b from the oil passage 6a is communicated with this expansion chamber 18, and two seal rings 19 are provided between the sleeve 16 and the inner surface of the opening 5 with the expansion chamber 18 in between. . A stopper 20 is fixed to the inner part of the opening 5 by a screw 21, a collet 22 is fitted inside the sleeve 16, and is fixed to the chuck body 1 together with the sleeve 16 by a stopper 23. ing. As shown in FIG. 2, the collet 22 has, for example, six grooves 24 arranged radially around the outer circumference and along the axial direction, one of which communicates with a slot 25 inserted in the axial direction. . These grooves 24 and slots 25 are filled with an elastic material 26 such as rubber by a method such as molding.

When using this device, first
Insert the tapered shank portion 2 into the shank. Next, the pull stud 9 is gripped and pulled by a well-known pulling means (not shown) provided inside the main shaft S, and the chuck body 1 is firmly fixed to the main shaft S. Subsequently, the object T to be held is inserted into the collet 22, and its tip abuts against the stopper 20. Then, when the piston rod 13 is pushed in the direction of arrow A, the oil filled in the oil passage 6, set screw 7, and expansion chamber 18 is pushed, and the thinned outer peripheral portion 17 of the sleeve 16 is elastically deformed. The sleeve 16 bulges inward. As a result, the object to be held T is firmly gripped via the collet 22. Also, when the piston rod 13 is pulled up, the oil comes out of the expansion chamber 18 and the sleeve 16
returns to its original state due to its elasticity, so the tightening of the held body T is loosened.

As means for pressing the piston rod 13 and piston 11, various conventionally known methods can be used. For example, a fluid actuator may be provided inside the main shaft S, and the piston rod 13 and the piston 11 may be operated by the forward and backward movement of the fluid actuator, or a solenoid or the like may be used instead of the fluid actuator. Note that it is also possible to omit the collet 22 and directly insert and hold the held object T into the sleeve 16.

FIG. 3 shows a second embodiment of the present invention, in which the held object T is opposite to the first embodiment.
An example of holding from the inside is shown. In FIG. 3, members that are the same as or equivalent to those in FIG. 1 are designated by the same reference numerals. The main difference from the first embodiment is that the rear end of the chuck body 1 has a cylindrical portion 2.
7, a thin sleeve 16 is fitted on the outside of this cylindrical part 27, and a held body T is fitted on the outside of this sleeve 16. In addition, oil path 6
is connected to the cylindrical part 2 through the shunt 6b at the middle of the cylindrical part 27.
7 and the cylindrical portion 27 and the sleeve 16
It communicates with an expansion chamber 18 formed between.

In the case of this embodiment as well, when the tip of the piston rod 13 is pressed in the direction of arrow A, the oil filled in the oil passage 6 and the expansion chamber 18 is pushed, and the outer circumference 17 of the sleeve 16 is elastically deformed outward. However, the object to be held T can be firmly tightened and held from the inside, and the tightening can be loosened by returning the piston rod 13 to its original position.

Although the first embodiment shows the case where the opening 5 is a straight hole with the same inner diameter, it is also possible to make this a tapered hole and adapt the sleeve 16 to form a tapered outer peripheral surface. . Also in the second embodiment, there is no problem even if the outer circumferential surface of the cylindrical portion 27 and the inner circumferential surface of the sleeve 16 are formed into a tapered shape.

[Effects of the Invention] As explained above, the hydraulic chuck device according to the present invention is capable of automatically tightening and loosening the held body by pressing or releasing the piston rod. Therefore, it can be attached to the main shaft of a machine as a basic chuck, and used to automatically attach and detach objects to be held, for example, by linking with an NC device, or to adjust the wrist of a robot according to the purpose. When replacing, it can be effectively used as a standard chuck device that can be automatically replaced.

Furthermore, since the piston rod is arranged in the axial direction via the pull stud, it is easy to apply it to ready-made machines. Furthermore, in the case of a structure using a collet, if the concave grooves and grooves provided in the collet are filled with an elastic material using a method such as molding, the intrusion of dust from the outside can be prevented, and the elastic material will prevent dirt from entering during use. There is also the advantage that the vibrations that occur are attenuated and the runout accuracy can be further improved.

Moreover, when used on a special machine such as a multi-axis machine, many tools are attached, so by using this device as a basic chuck when setting the tool length, the setting time can be greatly reduced. This makes it possible to significantly increase production efficiency.

[Brief explanation of the drawing]

The drawings show an embodiment of the hydraulic chuck device according to the present invention, FIG. 1 is a sectional view of the first embodiment, FIG. 2 is a sectional view taken along the line - in FIG. 1, and FIG. 3 is a sectional view of the second embodiment. FIG. 1 is the chuck body, 2 is the tapered shank portion, 4 is the cylindrical portion, 5 is the opening, 6 is the oil passage, 9 is the pull stud, 10 is the through hole, 11 is the piston, 1
2 is a ball, 13 is a piston rod, 14 is a flange, 15 is a counterbore, 16 is a sleeve, 17 is an outer periphery, 18 is an expansion chamber, 19 is a seal ring, 2
2 is a collet, 24 is a groove, 25 is a split, 27 is a cylindrical portion, S is a main shaft, and T is a held body.

Claims (1)

[Claims for Utility Model Registration] 1. A sleeve that is easily elastically deformable for gripping a held object is attached to the rear end of the chuck body whose front end is attached to the main shaft of a machine, and the sleeve and the An oil passage leading to an expansion chamber formed between the chuck body and the chuck body is formed on the same axis as a pull stud attached to the front end of the chuck body, and a piston rod is inserted into a through hole formed in the axis of the pull stud. , one end of the piston rod is a protruding end that protrudes outward from the end surface of the pull stud, the other end is connected to a piston inserted in the oil passage, and the protruding end is pushed inward to allow the piston rod to pass through the piston. The hydraulic chuck device is characterized in that the oil in the expansion chamber is pressurized to cause the sleeve to bulge toward the held object. 2. The hydraulic chuck device according to claim 1, wherein the sleeve is installed inside the chuck body and the expansion chamber is provided outside the sleeve. 3. The hydraulic chuck device according to claim 1, wherein the sleeve is attached to the outside of the chuck main body, and the expansion chamber is provided inside the sleeve. 4. A collet having an axial groove and a split is fitted into the sleeve, the collet is interposed between the sleeve and the body to be held, and an elastic material is fitted between the sleeve and the groove. A hydraulic chuck device according to claim 1 of the claimed utility model registration.