JPS60131116A - Tooling - Google Patents

Abstract

PURPOSE:To allow a swing machining method used in a machining center to work with its full performance by setting the speed difference between rotation and swinging of a tool in tooling such as tapping and boring by this method. CONSTITUTION:A prime motive shaft 1 is connected with a wave generator 4 of a decelerating device 3, which is composed of said wave generator 4, a flex spline 5 and a circular spline 6 in coaxial three-part construction, and either of the flex spline 5 and circular spline 6 is fixed and the other serves as output part. A rotary holder 9 is fixed to this output part, and a female screw 10 is provided at the tip of this rotary holder 9 coaxially with the abovementioned prime motive shaft 1 so as to serve screw fitting of a tool holder mounting spindle 11 thereon. At the inner wall of the holder 9, a crank shaft 12 is installed eccentrical from the prime motive shaft 1, and crank arms 13, 14 are fixed to the crank shaft on its both ends. The crank arm 13 is put in engagement with the abovementioned wave generator 4 and the other 14 with the spindle 11 so as to give swinging motion while it is rotating.

Description

[Detailed description of the invention] Conventionally, when tapping a thread, the ejection of chips is not smooth, and the cutting tool may be damaged due to excessive cutting force. In particular, the latest caution is required when tapping small diameter screws.

Therefore, various studies have been conducted to facilitate the tapping process, and the vibration cutting method has been developed as the most effective method. This vibration cutting method is a method in which tapping is performed while forcibly oscillating the blade (tap) or workpiece. According to this method, theoretically, the cutting resistance is reduced and no chips are generated. It is well known that such oscillating cutting has the following effects: good capture of screws, good burr-free tapping, and easy tapping of small-diameter screws. A screw tapping device that incorporates the law,
Many drilling devices, tooling, etc. have been researched and developed.

However, currently developed tools are equipped with separate drive sources for rotating and swinging the cutter, rotating the cutter,
Since the structure is such that the workpiece is oscillated, the structure of the device inevitably becomes complicated and large, and handling becomes troublesome. In addition, some tools have been developed in which the blade is rotated and oscillated by the same drive source, but
Since the rotation and swinging of the cutter lack smoothness, and the rotational speeds are close to each other, the theoretical effects of swinging can be produced, but both are impractical and have hardly been put into practical use.

This inventor has been researching the oscillating cutting method for a long time and is one of the people who established the oscillating cutting theory, but he has also continued research and development toward practical application, and has fully demonstrated the effects of the oscillating cutting method. We have completed a tooling for tapping and drilling using an oscillating cutting method that is small, easy to handle, and can be used in machining centers.

That is, the present invention connects a wave generator of a speed reduction device having a coaxial three-layer structure of a wave generator, a flex spline, and a circular spline to a driving shaft, fixes either the flex spline or the circular spline, and fixes the other. is an output part, a rotary holder is fixed to this output part, a female thread is provided at the tip of the rotary holder coaxially with the driving shaft, a tool holder main shaft is screwed into the female thread, and a rotary holder is fixed to the inner wall of the rotary holder. A crankshaft is provided at a position eccentric to the drive shaft so as to be rotatable in the coaxial direction, and crank arms are fixed to both ends of the crankshaft, one of the crank arms is connected to the wave generator, and the other is connected to the wave generator. The crank arm is engaged with the tool holder mounting spindle at an eccentric position, and the rotation of the wave generator causes the tool holder mounting spindle to swing through the crank arm and the crankshaft; The present invention is characterized in that the tool holder attachment main shaft is rotated through the rotary holder, which rotates due to the rotation of the output section of the speed reduction device.

Hereinafter, the present invention will be explained in detail based on embodiments shown in the drawings.

In the drawing, 1 is a driving shaft that rotates in response to the rotation of the main shaft 2 of the machining center, and 3 is a speed reduction device that decelerates the rotation of the driving shaft 1. This speed reduction device 3 is a flexure-mesh type speed reduction device composed of a coaxial three-layer structure of a wave generator 4, a flex spline 5, and a circular spline 6, and is capable of increasing the speed reduction ratio. It is generally known by the trade name of Harmonic Drive (trade name). The wave generator 4 of this speed reduction device 3 is connected to the driving shaft 1 and serves as an input section. In the output section, when either the flex spline 5 or the circular spline 6 is fixed, the other becomes the output section.

In the embodiment, the flex spline 5 is fixed and the circular spline 6 is used as the output section. 7 is a fixed circular spline for fixing the flexspline 5, and this fixed circular spline 7 is fixed to the casing 8 (fixed).

9 is a circular spline 6 which becomes the output part of the reduction gear device 3
A female screw 10 is provided at the tip of the rotary holder 9 coaxially with the driving shaft l and the wave generator 4. The pitch of this female thread 10 is not particularly limited in the case of drilling, but it is set to the same pitch as the screw to be inserted in the case of tapping.

A tool holder attachment main shaft ll is screwed into this female thread IO.

A crankshaft 12 is provided on the inner wall of the rotating holder 9 at a position eccentric to the driving shaft 1 and the wave generator 4 so as to be freely rotatable in the coaxial direction. This crankshaft 12
Crank arms 13 and 14 are fixed to both ends of the wave generator 4, and the crank arm 14 is connected to the tool holder attachment main shaft 11.
and are engaged at eccentric positions with respect to their axes. Specifically, a guide groove 15 is formed in the longitudinal direction in the crank arm 13, an eccentric pin 16 is provided in the wave generator 4 at a position eccentric to the coaxial center, and a shoe 17 is fitted onto the eccentric pin 16. 17 is engaged with the guide groove 15 of the crank arm 13. The shoe 17 is designed to slide along the guide groove 15 with little friction, and when the wave generator 4 rotates, the shoe 17 slides along the guide groove 15.
rotates while sliding in the guide groove 15 of the crank arm 13, and the rotation of the shoe 17 causes the crank arm 13 to swing at an angle proportional to the amount of eccentricity of the eccentric pin 16. In addition, the crankshaft 12
The crank arm 14 provided at the other end has a crankshaft 1
An eccentric pin 18 is provided at a position eccentric to the axis of the tool holder mounting main shaft ll and the axis of the tool holder attachment main shaft ll, and a shoe 19 is fitted to the eccentric pin 18. A motion transmission shaft 2 coaxially with the tool boulder mounting main shaft 11 and engaged with the main shaft 11
A guide groove 21 parallel to the crank arm 14 is provided at the end of the o.
is formed, and the shoe 19 is engaged with this guide 1121. The shoe 19 is designed to slide along the guide groove 21 with little friction, and when the crankshaft 12 swings in the circumferential direction via the crank arm 13 due to the rotation of the wave generator 4, the crank arm 14
The shoe 19 slides on the guide groove 21 and performs a swinging motion. The swing motion of the shoe 19 causes the motion transmission shaft 20 to swing in the circumferential direction, and the tool holder take-up main shaft 11 that engages with the motion transmission shaft 20 swings.

For the engagement between the tool holder attachment spindle 11 and the motion transmission shaft 2O, a square hole 22 is formed in the axial direction at the end of the tool holder attachment spindle 1'1, while the end of the motion transmission shaft 20 is formed in a square rod 23 having the same shape as the square hole 22, and the square rod 23 is fitted into the square hole 22 so as to be slidable in the axial direction.

When the driving shaft l rotates, the rotary holder 9 fixed to the circular spline 6, which is the output part of the reduction gear 3, is rotated at a predetermined rotation speed, and the rotary holder 9
The tool holder attachment main shaft ll, which is screwed into a female thread 10 provided at the tip of the tool holder, rotates. At the same time, the crank arm 13. Crankshaft 12. Crank arm 14. A high-speed swing motion in the circumferential direction of the shaft is transmitted to the tool holder attachment main shaft 11 via the motion transmission shaft 2o. As a result, the tool holder mounting main shaft 11 rotates slowly in response to the rotation of the rotary holder 9, and also rotates at high speed while sliding on the square bar 23 of the motion transmission shaft 2o in the lead angle direction of the female screw 10 in response to the swinging motion. It is designed to perform a rocking motion.

24 is pullstat, 25, 26.27 is nuts, 28
．． 29 is a bearing, 30.31 is an oil seal, 32 is a tool holder provided at the tip of the tool holder mounting spindle 11,
Reference numeral 33 denotes a rotation stopper provided on the outer wall of the casing 8, which engages with a positioning block 34 provided on the machining center to prevent rotation of the casing 8 when the tooling according to the present invention is set on the main shaft 2 of the machining center.

When tapping the tool with the above configuration on a machining center, the pitch is matched to the pitch of the female thread 10 provided at the tip of the rotary holder 9, and the tool holder 32 is tapped by the rotation of the main shaft 2 of the machining center. The attached cutter rotates while making a high-speed rocking motion in the direction of the lead angle of the female screw 10, and taps the screw by feeding the height according to the pitch of the female screw on the machining center. It is done in the same way as vertical machining, but in this case female thread 1
There is no need to pay attention to the pitch of 0.

As described above, according to the present invention, the rotary motion and rocking motion of the cutter are performed smoothly, and since the reduction gear used in the present invention can increase the reduction ratio, the rotary motion and rocking motion are smoothly performed. It is possible to increase the speed difference of dynamic motion,
The theoretical effects of rocking can be produced extremely effectively. In addition, the simple structure makes it compact and lightweight, making it easy to handle.Furthermore, since the drive shaft and cutter are coaxially located, it can be used in machining centers, making it particularly suitable as tooling for machining centers. It has a positive effect.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and FIG. 1 is a longitudinal sectional view, and FIG. 2 is a partially exploded perspective view of FIG. 1. l... Driving shaft, 3... Reduction device 4... Wave generator 5... Tsukless spline 6... Circular spline 9... Rotating holder, 10... Female thread 11... Tool holder installation Main shaft 12...Crankshaft 13.14...Crank arm

Claims (1)

[Claims] Wave generator, flex spline,
A wave generator of a speed reducer configured with a coaxial three-layer structure of circular splines is connected, either the flex spline or the circular spline is fixed, the other is used as an output part, and a rotation holder is fixed to this output part, A female thread is provided at the tip of the rotary holder coaxially with the driving shaft, a tool holder mounting main shaft is screwed onto the female thread, and a crankshaft is mounted on the inner wall of the rotating holder in a coaxial direction at a position eccentric to the driving shaft. A crank arm is fixed to both ends of the crankshaft, and one crank arm of the crank arm is eccentric to the wave generator, and the other crank arm is eccentric to the tool holder mounting main shaft. The rotation of the wave generator causes the tool holder attachment main shaft to swing through the crank arm and the crankshaft, and the tool holder is rotated by the rotation of the output section of the reduction gear. Tooling that rotates the tool holder mounting spindle.