JPH106130A - Double rotary sawtooth cutter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce vibration, and accurately cut a workpiece by arranging a planetary gear type speed reduction mechanism to rotationally drive paired circular sawteeth in the mutually opposite direction. SOLUTION: When a driving motor 11 is rotated, its rotation is reduced in speed by a planetary gear type speed reduction mechanism 12, and is transmitted to a third bevel gear 29. The third bevel gear 29 rotates first and second bevel gears 30 and 31 in the mutually inverse direction, and at the same time, also rotates first and second circular sawteeth 40 and 42 in the mutually inverse direction. Therefore, since reaction by the sawteeth 40 and 42 at workpiece cutting time is eliminated, operability is improved, and a workpiece can be quickly, accurately and stably cut.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double rotary cutting machine. More particularly, the present invention relates to a rotary cutter in which two circular saw blades are close to each other on the same central axis and are driven to rotate in opposite directions.

[0002]

2. Description of the Related Art A conventional rotary cutting machine used for cutting a pipe or the like is, as shown in FIG. 3, for example, provided with a shaft 2 provided at right angles to an elongated body 1 having a built-in drive unit. A circular saw blade 3 is mounted. The cutting operation is performed by holding the main body 1 by hand and pressing the rotating circular saw blade 3 against the workpiece.

[0003]

In such a conventional rotary cutting machine, when cutting a material, the reaction of the cutting force of the rotary blade is applied to the hand holding the main body 1, and therefore there is vibration, impact, and the like. Poor operability and safety. Therefore, there is a problem that accurate cutting cannot be performed.

[0004] In view of the above-mentioned conventional problems, an object of the present invention is to realize a rotary cutting machine which has good operability and can perform accurate cutting.

[0005]

In the rotary cutter according to the present invention, the first and second circular saw blades 40 and 42 are close to each other on the same central axis and opposite to each other. In a rotary driven double-rotation cutting machine, the first circular saw blade 40 is fixed to one end and the first bevel gear 30 is fixed to the other end; A second shaft 33 having a saw blade 42 fixed at one end and the second bevel gear 31 fixed at the other end, and rotatably inserted through the first shaft 32; Third bevel gear 29 commonly meshing with first and second bevel gears 30 and 31 attached to shafts 32 and 33
And a planetary gear-type reduction mechanism 12 that rotationally drives the third bevel gear 29 and a drive motor 11 that rotationally drives the planetary gear-type reduction mechanism 12.

[0006] In addition, a thin resin plate 45 is inserted between the two circular saw blades 40 and 42 to prevent contact between them. By adopting this configuration, it is possible to obtain a double-rotation cutting machine that has good operability and safety and can perform accurate cutting.

[0007]

FIG. 1 is a sectional view showing an embodiment of the present invention. In the figure, reference numeral 10 denotes a main body case of the rotary cutting machine. Inside the main body case 10, a drive motor 11 in a longitudinal direction thereof, a planetary gear type reduction mechanism 12 driven by the drive motor 11, A double reversing mechanism 13 driven by a planetary gear type reduction mechanism 12 is sequentially provided.

The planetary gear type speed reduction mechanism 12 driven by the drive motor 11 includes a plurality of planetary gears 15 (only one is shown in the figure) meshing with a pinion 14 formed on the rotation shaft of the drive motor 11. The gear 15 comprises a first rotating frame 19 rotatably supported by two ball bearings 17, 18 supported by a shaft 16, and a ring gear 20 fixed to the main body case 10 and engaged with the planetary gear 15. A first reduction unit, a plurality of planetary gears 22 (only one is shown in the figure) meshing with a pinion 21 provided on the first rotating frame 19, and the planetary gears 22 are supported by a shaft 23; A second rotating frame 26 rotatably supported by ball bearings 24 and 25, and the planetary gear 2 fixed to the main body case 10;
2 and a second reduction portion comprising a ring gear 27 meshing with the second reduction gear.

The contra-rotating mechanism 13 includes a third bevel gear 29 attached to a shaft 28 extending from a second rotary frame 26 of the planetary gear type reduction mechanism, and a third bevel gear 29.
And first and second bevel gears 30 and 31 of the same size that mesh with each other.

The first and second bevel gears 30, 31
Are fixed to first and second shafts 32 and 33 arranged at right angles to the longitudinal direction of the main body case 10, respectively. And a first shaft 3 having a first bevel gear fixed to one end.
2 has a cylindrical shape, is rotatably supported on the wall of the main body case 10 by a ball bearing 34, and has a flange 35 formed in a portion extending outside the main body case 10.

Also, a second bevel gear having a second bevel gear fixed to one end thereof is provided.
Shaft 33 is longer than the first shaft 32 and has a flange 36 at one end.
Is formed, and the shaft portion is inserted through the hollow portion of the first shaft,
Needle bearing 37 and bush 3 provided in the hollow portion
8 and the other end is supported by the main body case 10 via a ball bearing 39.

A first circular saw blade 40 is fixed to the flange 35 of the first shaft 32 with a knock pin or countersunk screw 41, and the second circular shaft 33 cannot rotate on the flange 36 of the second shaft 33. Between the presser plate 43 and the
The circular saw blade 42 is pressed and held and is fixed by a knock pin or countersunk screw 44. The first circular saw blade 40 and the second circular saw blade 42 are mounted such that the directions of the cutting blades are opposite to each other.

In this embodiment constructed as described above, by rotating the drive motor 11, the rotation is reduced by the planetary gear type reduction mechanism 12 and transmitted to the third bevel gear 29. The third bevel gear 29 rotates the first and second bevel gears 30 and 31 in directions opposite to each other, and simultaneously rotates the first and second circular saw blades 40 and 42 in directions opposite to each other. Thereby, the reaction by the saw blade at the time of cutting the workpiece is eliminated, so that the operability is improved, and the workpiece can be cut quickly, accurately and stably.

FIG. 2 is a diagram showing another embodiment of the present invention. In the figure, reference numeral 40 denotes a first circular saw blade, 42 denotes a second circular saw blade, and the first circular saw blade 40 is fixed to a flange 35 formed on a first shaft, and The circular saw blade 42 has a holding plate 43 attached to a flange 36 formed on the first shaft.
Is pressed and held. A feature of this embodiment is that a thin resin plate 45 is inserted between the first circular saw blade 40 and the second circular saw blade 42. The outer diameter of the resin plate 45 is substantially equal to the outer diameter of the flange 35 of the first shaft, and the thickness is preferably about 0.2 mm. As the resin material, a Teflon-based resin is preferable.

In the present embodiment configured as described above, the friction between the first and second circular saw blades 40 and 42 rotating in opposite directions can be reduced by the resin plate 45, and heat is generated. Can be suppressed.

[0016]

According to the dual rotary cutting machine of the present invention, the work piece can be cut accurately with low vibration and easy operation, and the resin plate is inserted between the two circular saw blades. By 2
Heat generation due to friction between the saw blades can be suppressed and stable cutting can be performed.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing another embodiment of the present invention.

FIG. 3 is a view showing a conventional rotary cutting machine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Main body case 11 ... Drive motor 12 ... Planetary gear type reduction mechanism 13 ... Double reversal mechanism 14, 21 ... Pinion 15, 22 ... Planetary gear 16, 23, 28 ... Shaft 17, 18, 24, 25, 34, 39 ... Ball bearings 19,26 ... Rotating frame 20,27 ... Ring gear 29 ... Third bevel gear 30 ... First bevel gear 31 ... Second bevel gear 32 ... First shaft 33 ... Second shaft 35, 36 ... Flange 37 ... Needle bearing 38 ... Bush 40, 42 ... Circular saw blade 41, 44 ... Knock pin or countersunk screw 43 ... Holding plate 45 ... Resin plate

Claims (2)

[Claims] A first and a second circular saw blade (40, 4).
2), which are close to each other on the same central axis and driven to rotate in opposite directions, wherein the first circular saw blade (40) is fixed to one end and the first circular saw blade (40) is fixed to the other end.
Cylindrical first shaft (32) to which the bevel gear (30) is fixed
And the second circular saw blade (42) is fixed at one end, the second bevel gear (31) is fixed at the other end, and the first shaft (3) is fixed.
A second shaft (33) rotatably inserted in 2);
A third bevel gear (29) commonly meshing with the first and second bevel gears (30, 31) attached to the first and second shafts (32, 33), and the third bevel gear; A planetary gear type reduction mechanism (12) for driving the gear (29) to rotate; and a drive motor (11) for rotating the planetary gear type reduction mechanism (12).
And a rotary cutting machine comprising: 2. The double rotary cutting machine according to claim 1, wherein a thin resin plate (45) is inserted between said two circular saw blades (40, 42) to prevent contact between them.