JPH08267322A - Threading device - Google Patents

Abstract

PURPOSE: To perform threading work accurately and easily by installing a boss to be engaged with a spline shaft, at one side, while attaching a threading tool to the other side, and installing a slide shaft provided with an external thread being screwed in a feed internal thread, in the circumference of an intermediate part. CONSTITUTION: An adjusting dial 43a is operated, and the projecting length of a cutting part 52 of a threading tool 50 is made into the extent of length conformed to a radius of a prepared hole 71. In this state intact, if a spindle 61 of a metalcutting machine tool is rotated and driven, driving force in this spindle 61 is transmitted to a slide shaft 40 via a spindle shaft 20, a spline shaft 22 and a boss, and thereby this slide shaft 40 performs its screw motion toward a workpiece 70 at the pitch of a feed screw (feed external thread 42 and feed internal thread 30). Accordingly, the threading tool 50 forms a thread groove in an inner circumference of the prepared hole 71 at the same pitch as the feed screw pitch.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thread cutting device capable of accurately and easily performing thread cutting with a general-purpose machine tool.

[0002]

2. Description of the Related Art Conventional thread cutting with a machine tool, especially when processing a screw having a relatively small diameter, a machine tool such as a milling machine, a machining center, or a dedicated tapping machine having a numerical control device is dedicated for thread cutting. It was done by attaching a tap, which is a tool.

[0003]

However, although the milling machine and the machining center having the above-described conventional numerical control device can perform accurate thread cutting, the numerical control device is expensive, and the numerical control device is used only for thread cutting. It could not be installed. Further, in thread cutting with a dedicated tapping machine, etc., it is necessary to accurately control the rotation speed and feed rate of the thread cutting tool according to the pitch of the thread to be processed, and this control requires a skill. It was

On the other hand, due to a shortage of skilled workers in recent years, thread cutting at a general machining site is performed exclusively by the above-described milling machine having a numerical control function, a dedicated tapping machine, etc., and general-purpose machine tools perform thread cutting. I couldn't. For this reason, a general-purpose machine tool has a problem that only thread cutting must be performed in a separate process.

Further, since the conventional machine tool described above is configured to use taps, it is only possible to perform thread cutting with a relatively small diameter, and special large-diameter thread cutting that cannot be performed with existing taps. There was a problem that I could not.

Incidentally, Japanese Patent Laid-Open No. 63-84815 and Japanese Patent Laid-Open No. 5-337730 propose a plate cutting machine having a spline and a feed screw. However, the spline and the feed screw in these cutting machines are for moving the cutter for cutting the plate material while rotating it, and do not solve the above problems at all.

The present invention has been made in view of the above problems, and it is possible to accurately and easily perform thread cutting with a general-purpose machine tool and to process a wide range of screws from small diameters to large diameters. The purpose of the present invention is to provide a thread cutting device that can be used.

[0008]

In order to achieve the above object, a threading device according to claim 1 of the present invention is a hollow case detachably fixed to a spindle head of a machine tool, and a hollow portion of the case. A spindle shaft rotatably supported on one side and a spline shaft on the other side, and a female screw fitted in the hollow part of the case; A boss that is rotatably supported in the hollow part of the case is provided on one side, a boss that engages with the spline shaft is provided, a thread cutting tool is attached on the other side, and a male screw that is screwed with the feed female screw is provided on the outer periphery of the intermediate portion. And a slide shaft.

According to a second aspect of the present invention, there is provided a thread cutting device in which the thread cutting tool is replaceable, and the thread cutting device according to the third aspect is capable of moving the thread cutting tool in a direction orthogonal to the slide shaft. It is configured to have a sharp blade.

[0010]

In the thread cutting device of the present invention having the above structure,
The connecting portion is connected to the spindle of the machine tool, the case is fixed to the spindle head of the machine tool, and the thread cutting device is attached to the machine tool. Then, the thread cutting tool of the present thread cutting device is aligned with the prepared hole previously formed in the workpiece.

Thereafter, when the main shaft of the machine tool is rotationally driven, this driving force is transmitted to the slide shaft via the spline shaft of the spindle shaft, and the slide shaft is driven by the pitch of the feed screw (feed male screw and feed female screw). It makes a spiral motion. Thereby, the thread cutting tool,
Threading is performed on the inner circumference of the pilot hole of the workpiece at the same pitch as the pitch of the feed screw.

Further, when the thread cutting tool has a blade portion movable in a direction orthogonal to the slide shaft, the protruding length of the blade portion is changed to change the screw diameter from a small diameter to a large diameter. Can be formed. Furthermore, when the screw cutting tool is configured to be replaceable, an existing tap can be used instead of the screw cutting tool.

[0013]

Embodiments of the thread cutting device of the present invention will be described below with reference to the drawings. First, a thread cutting device according to a first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a sectional view showing a thread cutting device according to a first embodiment of the present invention. The thread cutting device according to the first embodiment is configured to use a thread cutting tool in which a blade portion moves in a direction orthogonal to the slide shaft.

In the figure, reference numeral 10 denotes a case, which has a cylindrical shape. Inside the case 10, there are a spindle shaft 20, a female feed screw 30, and a slide shaft 4.
0 is accommodated, and a fixing portion 11 to the spindle head of a machine tool (not shown) is provided at the upper end.

The spindle shaft 20 is a rolling bearing 2
It is rotatably supported inside the case 10 via 0a and 20b. A connecting portion 21 with a main shaft of a machine tool (not shown) is integrally formed on the upper portion of the spindle shaft 20, and a spline shaft 22 is integrally formed on the lower portion.

The feed female screw 30 has a structure in which a female screw is formed on the inner circumference of a cylindrical member, and the pitch of this female screw is
It is the same as the pitch of the thread to be threaded. Further, the feed female screw 30 can be replaced with a feed female screw formed with a female screw having another pitch according to the pitch of the thread to be threaded.

The slide shaft 40 is located below the spindle shaft 20 inside the case 10 and is rotatably and vertically movably supported inside the case 10 through rolling slide bearings 40a and 40b. This slide shaft 40
A boss 41 for spline coupling with the spline shaft 22 is formed in the upper part of the above, and a feeding male screw 42 for screwing with the female feeding screw 30 is formed in the middle part. Also,
An attachment portion 43 for the thread cutting tool 50 is provided below the slide shaft 40.

The thread cutting tool 50 has a joint portion (not shown) with the mounting portion 43, a holder 51 fixed to the joint portion and protruding in a direction orthogonal to the slide shaft 40, and a blade fixed to the tip of the holder 51. And part 52. Such a thread cutting tool 50 is mounted on the holder 51 by rotating the adjustment dial 43a of the mounting portion 43.
Using a known adjusting device for adjusting the amount of movement of the blade 52
It is possible to adjust the protruding length of.

Next, the operation of thread cutting by the thread cutting device will be described with reference to FIG. FIG. 2 is a sectional view showing an operation of thread cutting by the present thread cutting device.

When the workpiece 70 is to be thread-cut by the present thread cutting device, the connecting portion 21 is connected to the spindle 61 of a machine tool (general-purpose machine tool) (not shown) and is fixed to the spindle head 62 of the machine tool. Fix the part 11,
The threading device is attached to the machine tool.

The center of the thread cutting device is the workpiece 7.
The spindle head 62 of the machine tool is moved so as to coincide with the center of the prepared hole 71 of 0, and the main threading device is aligned. Also, at this time, by operating the adjustment dial 43a,
The protruding length of the blade portion 52 of the thread cutting tool 50 is set to a length corresponding to the radius of the prepared hole 201.

In this state, when the main shaft 61 of the machine tool is rotationally driven, the driving force of the main shaft 61 is transmitted to the slide shaft 40 via the spindle shaft 20, the spline shaft 22 and the boss 41, and the slide shaft 40 is machined. In the direction of the object 70, a feed screw (feed male screw 42
And the spiral movement of the feed female screw 30). Thereby, the thread cutting tool 50 forms a thread groove on the inner circumference of the pilot hole 71 at the same pitch as the pitch of the feed screw.

When the thread cutting process is completed, the spindle 61
Stop the rotation drive of. And the adjustment dial 43a
Is operated to make the protruding length of the blade 52 shorter than the radius of the pilot hole 71. After that, when the main shaft 61 is rotationally driven in the direction opposite to the B direction, the thread cutting tool 50 returns to the position at the start of thread cutting through the prepared hole 71 by the action of the feed screw.

Further, when deep thread cutting that is impossible with a single operation is performed, the protruding length of the blade 52 is readjusted, the spindle 61 is rotated in the B direction, and the above-described machining operation is repeated a plurality of times. In this case, since the blade portion 52 traces the same axis trace unless the position of the present thread cutting device is moved, a continuous spiral thread groove can be formed in the deep pilot hole 71.

According to the thread cutting device of the first embodiment having the above-mentioned structure, the thread cutting tool 50 causes the feed screw (feed male screw 4) by applying the rotational force of the main shaft 61.
Since the thread cutting is performed at the same pitch as the pitch of the 2 and the feed female screw 30), the thread cutting can be accurately and easily performed by a general-purpose machine tool.

By changing the protruding length of the blade portion 52 of the thread cutting tool 50, it is possible to form a screw having a small diameter to a large diameter. Furthermore, by exchanging the feed male screw 42 (slide shaft 40) and the feed female screw 30 with other feed male screws and feed female screws having different pitches, thread cutting with various pitches can be performed.

Next, a thread cutting device according to a second embodiment of the present invention will be described with reference to FIG. FIG. 3 is a side view showing a thread cutting device according to a second embodiment of the present invention.

In the thread cutting device of this embodiment, a grip portion 44 capable of gripping various thread cutting tools is provided at the lower end of the slide shaft 40, and an existing tap 80 other than the thread cutting tool 50 can be used. . In the present thread cutting device having such a configuration, the thread cutting is performed by matching the pitch of the tap 80 with the pitch of the feed screw (the feed male screw 42 and the feed female screw 30). According to such a thread cutting device of the second embodiment, it is possible to perform re-tap which is usually difficult with a machine other than a dedicated machine, and it becomes easy to additionally process the depth of the screw hole.

[0029]

As described above, according to the thread cutting device of the present invention, it is possible to accurately and easily perform thread cutting with a general-purpose machine tool and to process a wide range of screws from small diameters to large diameters. You can

[Brief description of drawings]

FIG. 1 is a sectional view showing a thread cutting device according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing an operation of thread cutting by the thread cutting device.

FIG. 3 is a side view showing a thread cutting device according to a second embodiment of the present invention.

[Explanation of symbols]

 10 Case 11 Fixed part 20 Spindle shaft 20a, 20b Rolling bearing 21 Connecting part 22 Spline shaft 30 Feed female screw 40 Slide shaft 40a, 40b Rolling slide bearing 41 Boss 42 Feed male screw 43 Mounting part 43a Adjustment dial 44 Gripping part 50 Thread cutting tool 51 Holder 52 Blade

Claims (3)

[Claims] 1. A hollow case detachably fixed to a spindle head of a machine tool, and a connecting portion rotatably supported in the hollow portion of the case and connected to one side of the spindle of the machine tool. In addition, a spindle shaft provided with a spline shaft on the other side, a female feed screw fitted in a hollow portion of the case, a boss rotatably supported in the hollow portion of the case, and a boss that engages with the spline shaft on one side. And a slide shaft provided with a thread cutting tool on the other side, and provided with a male screw on the outer periphery of the intermediate portion, the male screw screwing with the female feeding screw being provided. 2. The thread cutting device according to claim 1, wherein the thread cutting tool is replaceable. 3. The thread cutting device according to claim 1, wherein the thread cutting tool has a blade portion movable in a direction orthogonal to the slide shaft.