Air chuck device

Abstract

This invention provides an air chuck device that allows for fine axial adjustment of the collet chuck by rotating an adjuster while the rotary cylinder remains attached to the spindle of the machining center. [Solution] The system comprises a collet housing 4, a rotary cylinder 16 attached to the spindle 2 of a machining center and on which a piston 22 is positioned, and an air circulation pipe 12 that passes through the rotary cylinder. An adjuster 38 for manual rotation is fitted and fixed to the outer surface of the air circulation pipe. A through hole 40 is provided in the adjuster, and an engaging body 48 biased by an elastic means is positioned in the through hole. Multiple engaging recesses are provided in the circumferential direction of the surface of the rotary cylinder that engages with the adjuster, and the engaging body can be fitted into any engaging recess by rotating the adjuster by hand.

Description

Technical Field

[0001] The present invention relates to an air chuck device for controlling a collet chuck used in a machine tool such as a NC lathe, and more particularly to an air rotary cylinder.

Background Art

[0002] An air chuck device including a rotary cylinder, a collet chuck, and a drawbar has been conventionally known (see Patent Document 1). In addition, an air chuck device is known, which includes a machine tool spindle, a collet housing attached to the tip side of the machine tool spindle, a rotary cylinder attached to the rear end side of the machine tool spindle, a piston built in the rotary cylinder, an air flow pipe penetrating the rotary cylinder, a rotary joint having a mechanism for supplying air for piston operation through the air flow passage of the pipe, and a drawbar having one side coupled to the other side of the air flow pipe via an adjustment screw and the other side coupled to a collet chuck disposed in the collet housing.

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0003] In a lathe (machine tool) using general numerical control, when trying to hold a workpiece with a collet chuck, the method for adjusting the axial position of the collet chuck is to remove the rotary cylinder from the main spindle of the machine tool, rotate the rotary cylinder, and perform fine adjustment of the axial direction of the collet chuck. Once the collet chuck reaches the optimal position, the rotary cylinder is fixed to the main spindle of the machine tool again. Thus, the conventional method requires the removal and reinstallation of a heavy air cylinder, and there is a possibility that the position of the collet chuck may shift when the air cylinder is reinstalled. In that case, readjustment will be necessary. The purpose of this invention is to solve the above-mentioned problems. [Means for solving the problem]

[0004] To achieve the above objective, this invention comprises a machining center spindle (2), a collet housing (4) attached to the tip side of the machining center spindle (2), a rotary cylinder (16) consisting of a body (16a) and a cover (16b) attached to the rear end side of the machining center spindle (2), a piston (22) housed within the rotary cylinder (16), an air circulation pipe (12) positioned through the rotary cylinder (16), a rotary joint (18) attached to one side of the air circulation pipe (12) and having a mechanism for supplying air for piston operation through the air passages (24) (26) of the pipe (12), and one side of which is connected to the other side of the air circulation pipe (12) via an adjustment screw (10), and the other side being positioned within the collet housing (4). An air chuck device comprising a drawbar (8) coupled to a collet chuck (23) placed on the surface, wherein the drawbar (8) can be slid axially by rotating the air circulation pipe (12), characterized in that a manual rotation adjuster (38) is fitted and fixed to the outer circumferential surface of the air circulation pipe (12), a through hole (40) is provided in the adjuster (38), an engaging body (48) biased by an elastic means is placed in the through hole (40), a plurality of engaging recesses (44) are provided in the circumferential direction of the surface of the cover (16b) of the rotary cylinder (16) that fits with the adjuster (38), and the engaging body (48) can be fitted into any engaging recess (44) by rotating the adjuster (38) by manual operation. Furthermore, this invention is characterized in that the resilience means is a compression coil spring (42). Furthermore, this invention is characterized in that the engaging body (48) is a steel ball. Furthermore, this invention is characterized in that the engaging recess (44) has a semi-curved recess shape. [Effects of the Invention]

[0005] As described above, this invention reduces the adjustment work because it does not require removing the rotary cylinder from the machining center spindle to adjust the position of the collet chuck. Furthermore, the collet chuck position adjustment process involves fewer steps, allowing it to be completed in a short amount of time. Furthermore, since there is no need to install a rotary cylinder to adjust the position of the collet chuck, there is no misalignment of the collet chuck position after adjustment. Furthermore, the adjustment pitch for the collet chuck position can be made finer than it is currently. [Brief explanation of the drawing]

[0006] [Figure 1] This is an overall cross-sectional diagram illustrating the air chuck device according to the present invention. [Figure 2] This is an explanatory diagram of the cross-section of line AA. [Figure 3] This is an enlarged explanatory diagram of section B in Figure 2. [Modes for carrying out the invention]

[0007] The configuration of this invention will be described in detail below with reference to the attached drawings. First, let me explain how the air chuck device works. In Figure 1, 2 is the spindle of a tubular machining center, to which a collet housing 4 is fixed via a screw fitting, and to which a mounting flange 6 is fixed via a screw fitting. A tubular drawbar 8 is positioned on the spindle 2 of the machining center, and an air flow pipe 12 is connected to one end of the drawbar 8 via an adjustment screw 10.

[0008] The adjustment screw 10 consists of a female thread formed on the inner surface of the drawbar 8 and a male thread formed on the outer surface of the pipe 12 that screws into it. 14 is the air rotary cylinder section, which consists of an air rotary cylinder 16 and a rotary joint 18. The main spindle 2 of the machining center is fixed to the body 16a of the rotary cylinder 16 via a mounting flange 20 using a screw.

[0009] A piston 22 is positioned in the rotary cylinder 16, and the inner diameter of the piston 22 is slidably fitted to the outer surface of the pipe 12. Air passages 24 and 26 are formed in the circumferential wall of the pipe 12, and air for gripping and releasing the chuck is supplied into the rotary cylinder 16 from the rotary joint 18 via the air passages 24 and 26. A collet chuck 23 is connected to the tip of the drawbar 8.

[0010] When air is supplied from the processing machine's air source (not shown) to the chuck gripping air supply port 28 of the rotary joint 18, the air is supplied to one side of the piston 22 via the air passage 26, pushing the piston 22 to the left in Figure 1. As the piston 22 moves to the left in Figure 1, the pipe 12 and the drawbar 8 move in the left axis direction in Figure 1, causing the collet chuck 23 inside the collet housing 4 to be pulled inward, reducing the diameter of the collet chuck 23 and gripping the workpiece 32.

[0011] Furthermore, when the supply of air from the air source for gripping the workpiece in the rotary joint 18 is stopped and air is supplied to the air supply port 30 for chuck release, the air is supplied to the other side of the piston 22 via the air passage 24, pushing the piston 22 to the right in Figure 1. As the piston 22 moves to the right in Figure 1, the pipe 12 and the drawbar 8 move axially to the right in Figure 1, pushing the collet chuck 23 outward from the collet housing 4, causing the collet chuck 23 to be displaced in the diameter expansion direction, resulting in the workpiece release state.

[0012] The outer circumference of the cover 16b of the rotary cylinder 16 is fixed to the body 16a of the rotary cylinder 16 by bolts 33. The inner diameters of the body 16a and cover 16b of the rotary cylinder 16 are fitted to the outer surface of the pipe 12 via bearings 34 and 36. A boss portion 16c is formed on the inner diameter of the cover 16b of the rotary cylinder 16, and the annular recess 38a of the adjuster 38 is fitted into it.

[0013] The adjuster 38 has a step and comprises a first outer surface 38b and a second outer surface 38c adjacent to it, which has a smaller diameter than the outer surface 38b. The adjuster 38 is fixed to the pipe 12 by a screw 41, with its shaft hole fitted to the outer surface of the pipe 12. A through hole 40 is formed in the pipe wall where the second outer surface 38c of the adjuster 38 is located, perpendicular to the central axis of the shaft hole 38a of the adjuster 38. A compression coil spring 42 is compressed and positioned in the through hole 40.

[0014] On the inside of the boss portion 16c of the cover 16b of the rotary cylinder 16, 24 engagement recesses 44, each consisting of a hemispherical groove, are drilled at equal intervals, and each recess 44 is formed on a circular line 46 centered on the central axis of the boss portion 16c (see Figure 3). An engaging body 48 made of a steel ball is placed in the through hole 40, and the engaging body 48 is pressure-fitted into the opposing engaging recess 44 by the elasticity of a compression coil spring 42. The adjuster 38 is connected to the pipe 12 by the pressure of the screw 41, and the adjuster 38 and the pipe 12 are configured to move in conjunction in the rotational direction. The through hole 40 is configured to open into the circular line 46 set on the inner circumferential surface of the boss portion 16c of the cover 16.

[0015] The adjuster 38, through-hole 40, compression coil spring 42, engaging body 48, and engaging recess 44 constitute the position adjustment mechanism of the collet chuck. When the spherical surface of the engaging body 48 is fitted into the groove of the engaging recess 44 by the elastic force of the compression coil spring 42, the connection state of the adjuster 38 to the rotary cylinder 16 is stable. In this state, when a rotational force greater than a predetermined value is applied manually to the adjuster 38, by this rotational force, the engaging body 48 is pressed against the curved surface of the engaging recess 44 and is pushed inward in the through-hole 40 against the elastic force of the compression coil spring 44.

[0016] As a result, the fitting state between the engaging body 48 and the engaging recess 44 is disengaged, and the adjuster 38 rotates with respect to the cover 16b of the rotary cylinder in the direction of the applied manual rotational force. By this manual rotation of the adjuster 38, the pipe 12 rotates with respect to the drawbar 8, and by the action of the adjusting screw 10, the drawbar 8 slides axially with respect to the pipe 12, and the position of the collet chuck 23 changes.

[0017] When the collet chuck 23 is set at an optimal position and the engaging body 48 is opposed to an appropriately selected engaging recess 44 by manually rotating the adjuster 38, the engaging body 48 is press-fitted into the opposing engaging recess 44 by the elastic force of the compression coil spring 44. When the engaging body 48 is fitted into the engaging recess 44, the adjuster 38 is in a connected state with respect to the rotary cylinder 16, and the position adjustment of the collet chuck 23 is completed. In this embodiment, 24 engaging recesses 44 are provided inside the boss portion 16c of the cover 16b of the rotary cylinder, but it is not particularly limited to this number. The engaging recesses 44 can be provided on the circular line 46 at an arbitrary fine pitch.

Explanation of Reference Numerals

[0018] 2 Machine spindle 4 Collet housing 6 Mounting flange 8 Drawbar 10 Adjusting screw 12 Air circulation pipes 14 (Air) Rotary Cylinder Section 16 (Air) Rotary Cylinder 16a Main Unit 16b Cover 16c Boss section 18 Rotary Joint 20 Mounting flange 22 pistons 23 Collet Chuck 24 Air passage 26 Air passage 28 Air supply port 30 Air supply ports 32 Work 33 volts 34 bearings 36 Bearings 38 Adjuster 38a Annular recess 38b Outer surface 38c Outer surface 38d shaft hole 38e tube wall 40 Through holes 41 screws 42 Compression coil spring 44 Engagement recess 46 yen line 48 Engaging body

Claims

1. The machine spindle (2), a collet housing (4) attached to the tip side of the machine spindle (2), a rotary cylinder (16) attached to the rear end side of the machine spindle (2) consisting of a body (16a) and a cover (16b), a piston (22) housed inside the rotary cylinder (16), an air circulation pipe (12) positioned through the rotary cylinder (16), a rotary joint (18) attached to one side of the air circulation pipe (12) and having a mechanism for supplying air for piston operation through the air passages (24) (26) of the pipe (12), and a collet chuck ( ) whose one side is connected to the other side of the air circulation pipe (12) via an adjustment screw (10) and whose other side is located inside the collet housing (4) An air chuck device comprising a drawbar (8) coupled to a 23), wherein the drawbar (8) can be slid axially by rotating the air circulation pipe (12), characterized in that a manual rotation adjuster (38) is fitted and fixed to the outer circumferential surface of the air circulation pipe (12), a through hole (40) is provided in the adjuster (38), an engaging body (48) biased by an elastic means is placed in the through hole (40), a plurality of engaging recesses (44) are provided in the circumferential direction of the surface of the cover (16b) of the rotary cylinder (16) that engages with the adjuster (38), and the engaging body (48) can be fitted into any engaging recess (44) by rotating the adjuster (38) by manual operation.

2. The air chuck device according to claim 1, characterized in that the elastic means is a compression coil spring (42).

3. The air chuck device according to claim 1, characterized in that the engaging body (48) is a steel ball.

4. The air chuck device according to claim 1, characterized in that the engaging recess (44) has a semi-curved recess shape.

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