JPS60141446A - Rotary tool holder - Google Patents

Abstract

PURPOSE:To improve working efficiency by installing a tool holding shaft onto the main shaft of a holder through a planetary gear mechanism so that the center of a rotary tool is provided with eccentric revolution. CONSTITUTION:The captioned apparatus is constituted of a holder main shaft 1 for directly connecting a tool holder to the driving shaft 2 of a working machine 7 and a tool holding shaft 12 connected to the main shaft through a planetary gear 6 mechanism, and the captioned holder is designed to an integral type structure by installing the planetary gear 6 mechanism into the main shaft 1, and a rotary tool 11 held onto the tool holding shaft 12 by the planetary gear 6 mechanism is provided with the high-speed revolution due to the self-reliance speed increase, and the tool holding part of the tool holding shaft 12 is installed around the center of the rotary shaft, permitting eccentric revolution, and thus the desired eccentric revolution can be obtained easily. Therefore, the proper selection of the worked surface and the high efficiency in machining are permitted by the speed increase by the planetary gear 6 mechanism and the eccentric revolution of the center of revolution of the tool around the center of revolution of the main shaft.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a holder for rotatably holding a cutting or other rotary tool, which can easily self-increase the original rotational speed of a drive shaft, and can rotate a single-rotary tool by the speed-increasing speed. The present invention relates to a device that is eccentrically rotatable around its rotation center under rotation.

It is well known that when a cutting or other rotary tool is mounted on each processing machine, a holder on which the tool is mounted is attached to the drive shaft of the machine. For example, in the case of tools such as cutting cutter blades.

If the cutter blade can be rotated eccentrically around the center of rotation to accommodate changes in cutter diameter due to wear of the cutter blade, re-IT polishing, etc., it is possible to cope with changes in the cutter diameter even if the required cutter diameter is not exact. Even when performing machining that requires accuracy of one dimension, such as groove machining, if the cutter blade is set to rotate eccentrically, accurate 11 dimensions can be obtained by adjusting the amount of eccentricity. It would be extremely advantageous to allow the cutter blade to rotate eccentrically around the axis 1u while rotating around the rotation axis. Holders that satisfy this purpose already exist, but in conventional structures, the main part of the holder and the eccentric part have relative structures that allow them to slide, so it is difficult to design them as an integral structure. There are concerns about the rigidity of the entire holder, making it difficult to use for light-load cutting, but not suitable for heavy-load cutting such as end milling. In addition, when applying rotation to the tool from the drive shaft via the holder, conventionally, when applying high-speed rotation only to the cutter blade that is arranged coaxially with the drive shaft center, it is difficult to apply rotation to the cutter blade other than the drive shaft. In order to rotate only the blade at an increased speed, it is necessary to use a separate drive source such as a high frequency motor or an air motor, which is disadvantageous in terms of cost and structure. In this case, in the type that enables eccentric rotation, it is necessary to install a lead wire or pipe as a driving medium passage for the driving source in the eccentric structure, which complicates the structure and makes it difficult to change tools. Such shortcomings are a sign of weakness.

The great invention was made in order to solve the problems with conventional holders for this type of rotary tool, and for this reason, the great invention has a tool holder with a holder main shaft that is directly connected to the drive shaft of a processing machine, and a rib main shaft. The tool holding shaft is connected to the main shaft via a planetary gear mechanism, and the planetary gear mechanism is housed in the main shaft, resulting in an integrated structure β holder design.
In addition, the planetary gear mechanism allows the rotary tool held on the tool holding shaft to easily undergo high-speed rotation due to self-blade speed increase, and furthermore, the tool holding portion of the tool holding shaft is
The desired eccentric rotation can be easily obtained by providing eccentric rotation around the rotation axis,
Therefore, its features include a holder main shaft that is connected to the drive shaft and can rotate at the same speed, and a planetary gear mechanism built into the holder main shaft around the main shaft, which is connected to the holder main shaft so that it can rotate at increased speed. The holding part of the rotary tool is comprised of a tool holding shaft which is eccentrically rotatable with respect to the rotation axis U.

The great invention will be described in detail below with reference to the illustrated embodiments.

In Fig. 1, the holder main shaft (1), whose one end for connection is a shank portion, is press-fitted and engaged with the drive shaft (2) of a required processing machine (7) by mutual tapered slope fitting portions. At the same time, the facial part i[tltM
The rotation of I21 is controlled by the drive key (3) protruding from the shaft (2).
) and the key (3) are transmitted to the main shaft full side by a key groove (4) formed on a part of the outer periphery of the main shaft (1). ([7) The connection of the holder main shaft (1) to the drive shaft (2) and the rotation transmission structure are not limited to the illustrated example.

An outer cylinder (9) is wrapped around the front outer periphery of the holder main shaft fil via a bearing (18), and the outer cylinder (9) has a fixing pin protruding from a processing machine (7) on a part of its outer periphery. (8) is held fixed by being engaged through the spring OI.

On the inner circumferential surface of this outer tfA191, the drive shaft (2) and the axial center (rotation center) of the holder main shaft f11 and an internal gear (lO) of @l +l> are integrally formed fF, and this internal gear (
A planetary gear (6) rotatably held by a bottle shaft fixed at a predetermined radial position from the rotation center at the front end of the holder main shaft (1) is internally meshed with lO).

For this holder main shaft (]), the required rotary tool is shown as an example of a cutting cutter OD in the figure,
A tool holding shaft (2) that detachably holds the cutter 〇〇, for example, with a taper collet chuck holder as shown in the figure.
is integrally provided with a sun gear concentric with the rotation center at one end opposite to the mounting side of the cutter aη, and by meshing the gear α with the planetary gear (6), the holder main shaft (+1 and The tool holding shaft a2 is concentrically connected to the internal gear (1
0) Connected by a planetary gear mechanism with a planetary gear (6) and a sun gear θ.

Furthermore, the tool holding shaft (+2) is held so that its entirety can freely rotate eccentrically around the center of rotation, and the eccentric rotation for this purpose can be freely designed as an IJ mechanism. The example shown uses a double eccentric cylindrical structure.In other words, the tool support shaft (2) is connected to the bearing cage 11.
The rotating eccentric inner cylinder A4 is externally fitted and supported via the .

Its inner diameter surface is centered with the axis of the support shaft (2) (rotation center of the tool oD), but its outer diameter surface is a cam cylinder eccentric with the axis of the support shaft surface, and this rotating eccentric inner cylinder a The fixed eccentric outer cylinder QG that is externally fitted on the chrysanthemum is a cam cylinder whose inner diameter surface is eccentric to the axis of the support shaft (2) and whose outer diameter surface is pivoted to the axis,
One end of the fixed eccentric external flit Q5 is fixed to a part of the front end surface of the holder main shaft (1), +22
Reference numeral 1 indicates a removal stopper interposed between the eccentric inner and outer radial surfaces of both cylinders Q41 (to), and reference numeral 1) indicates a set screw screwed into a part of the circumferential side of the outer cylinder ao.

According to the tool holder according to the great invention, the cutting cutter aη, which is a one-rotation tool, is attached to the drive shaft (2) in the state shown in the first figure and configured as follows. Along with the rotation (autorotation) due to the increased rotational speed as shown in FIG. With the rotation of 2), the holder main shaft i11
are rotated together at the same speed, and the rotation is caused by the internal gear (
10) The rotation of the holder main shaft (]) is transmitted to the two-piece support shaft (2) through the planetary gear (61 sun gear 03), as shown in the schematic diagrams shown in Figures 2a and 2b. At the same time, the planetary gear (6) integrated therewith revolves in unison with the fixed internal gear (10) via the pin shaft 15), and at the same time, by rotating the sun gear 03, the entire sun gear θ is rotated. If the diameter of the planetary gear (6) is Za, the diameter of the planetary gear (6) is zb, and the diameter of the internal gear (10) is ZC, then the planetary gear (6)
) The rotation speed Na of the sun gear for one revolution is Na
= (1+Z0/za)
Since a-(1+Z(/za)Nd, (Zc-
The rotational speed is further increased by Ncl)/Za. However, for this Zc = + za +2Z
It is necessary to satisfy the requirement b, and in this case, the rotation direction of the holder main shaft ill and the sun gear Q3 is the 1Eil direction. Furthermore, in the uninvention, the tool holding shaft 0O, which is integral with the solar inner wheel a frame which is rotated at an increased speed, is not simply rotatably supported at the center of rotation, but is supported by a fixed eccentric outer cylinder 0Q and a rotating eccentric inner cylinder αa. Since it is held by a combined eccentric rotation mechanism, eccentric movement can be given in the direction of the arrow KP as shown in Fig. 2b, and the cutter θ inserted into the holding shaft (6) can be moved eccentrically in the direction of the KP arrow as shown in Fig.
When the rotation speed of υ is increased several times with respect to the holder main shaft H, it rotates eccentrically at 1ijt, and performs a movement that revolves around the rotation center of the main shaft +1). In this way, the center of rotation of the cutting cutter α makes a planetary motion around U during the rotation of the main axis +1+, and as shown in FIG. On the other hand, even if a small-diameter cutting cutter αυ is used, the cutting process can be suitably performed as if it were processed by a large-diameter cutting cutter.
C shows the rotation locus of the center of rotation, and C indicates the feeding direction of the broken workpiece. Although not shown here, if the amount of eccentricity can be adjusted, it is also possible to set the machining lJ independently of the cutter diameter within a certain range.

The above-mentioned embodiment is based on an uninvented example, and the rotation mechanism for making the eccentric surface 1# with respect to the tool holding shaft (6) can be adopted other than the example shown. but.

It is preferable to provide it around the holding axis as much as possible. For mounting various rotary tools, including the cutting cutter 00, to the tool holding shaft 0'J, instead of using the taper collet chuck system shown in FIG. 1, for example, as illustrated in FIG. 4,
Insert the canter 0υ into the tool holding shaft (2) at iα contact, I)
, side I grip type screws (17I) are also effective; 00 indicates the cutter insertion hole.

The uninvented tool holder has advantages over conventional holders in the following points due to the speed increase by the planetary gear mechanism and the eccentric rotation of the tool rotation center around the spindle rotation center.

(1) Eccentric rotation that can respond to changes in tool outer diameter due to rotary tool wear, regrinding, etc. makes it possible to easily obtain an appropriate machining 1h1 even if the required tool diameter is not accurate. By adjusting the eccentricity m, it is possible to provide more appropriate machining motion contents.

+2) Therefore, even when performing machining with strict dimensions such as round groove machining (1), it is easy to perform machining with dimensions of one comb by adjusting the amount of eccentricity. This makes it possible to easily adjust the hole diameter when various hole machining is performed using an end mill or the like.

(3) It is possible to give the tool several times the rotation speed of the drive shaft (2), for example, the rotation speed of the drive shaft (2) is 100 or
Since the speed of m can be increased to 500 Or'pm, it is possible to improve the efficiency of processing including cutting, and since there is no need for a separate speed-increasing prime mover, it is economical.

(4) Regardless of whether it is a specialized processing machine or a general-purpose processing machine, d' can be applied without invention, and with its speed increase function and tool diameter correction function, high-speed and precision machining can be easily achieved. In addition, the planetary gear mechanism and eccentric rotation mechanism can be compactly incorporated into the holder body as part of the structure, and furthermore, the holder can be designed as an integral part of the entire holder, making it easy to construct it as a solid and rigid body. You can get it.

As described above, the uninvented invention enables the rotation and revolution of the tool by using the drive shaft of the processing machine as the only drive source, improving the machining range and content, and also making it easier to change the tool. It does not cause any trouble and has great utility as an improved tool holder.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional front view of the embodiment of the invention, Fig. 2a. FIG. 2b is a schematic diagram illustrating the motion content of the main mechanism in the present invention, and FIG. 3 is an explanatory diagram of one example of the same cutting process. FIG. 4 is a sectional view of essential parts of an embodiment of the tool attachment/detachment structure. (1)...Holder main shaft, (2)...Drive shaft: 6
)...pin shaft, (6)...planetary gear, +10)・
...Internal gear, Qυ...Cutting cutter. (2)...Tool holding shaft, α...sun gear, σ4...
・Rotating eccentric inner cylinder, θQ...Fixed eccentric outer cylinder. Patent applicant Osawa Seisakusho Co., Ltd.

Claims (1)

[Claims] 1. A holder main shaft that is connected to a drive shaft so that it can rotate at the same speed, and a holder main shaft that is connected to the holder main shaft so that it can rotate at increased speed through a planetary gear mechanism built around the main shaft, and that holds the rotating tool. A rotary tool holder characterized in that a portion thereof comprises a tool holding shaft which is eccentrically rotatable with respect to the rotation center.