JPS59232718A - Hob for hourglass worm wheel gear cutting - Google Patents

Abstract

PURPOSE:To improve the manufacturing efficiency of a hob as well as to heighten hobbing accuracy, by making up a setting surface being paralleled with a hob spindle in relatiuon to an arbor, while locking a flat platelike cutter body carrying a cutting edge of more than two screw threads detachably to this setting surface. CONSTITUTION:Each flat platelike cutter body 2 to be set to a setting surface 11 is provided with each cutting edge 21 consisting of at least two screw threads or more. The cutting edge 21 of each cutter body 2 is optionally formed after being calculated in conformity with each tooth profile of a hourglass worm wheel to be created. Each of these flat platelike cutter bodies 2 is restrained in movement and positioned between a cam lock 5 and a cam piece 51 and locked to the setting surface 11 by means of bolts 3. Therefore, a manufacturing process comes easy.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an hourglass-shaped worm wheel gear cutting hob.The hourglass-shaped worm wheel gear cutting hob of the present invention allows the hob itself to be manufactured easily and efficiently.
This was proposed to obtain a highly accurate hob, and the
On the other hand, a mounting surface parallel to the hob shaft is formed, and a flat plate-shaped blade body having a cutting edge equal to or more than two screw threads is removably fixed to the mounting surface.

The present invention will be explained below based on embodiments shown in the drawings.

1 is a hob body whose center part is hourglass-shaped, and the center part of the arm μ1 forms a multi-face 11 parallel to the hob axis l.The term "hob axis" used in this specification l
As shown in the example, the "mounting surface 11 parallel to" includes "the mounting surface 11 including the hob shaft I!". Reference numeral 12 denotes a receiving surface that is substantially perpendicular to the mounting surface 11, and serves to position the base end of the force-generating body 2 when the flat blade body 2, which will be described later, is brought into contact with the mounting surface 11.

Although the mounting surfaces 11 in the illustrated example AR μ1 are provided at two locations separated by an angle of approximately iso' in the circumferential direction, they may be provided at one location or at three or more locations.

Reference numeral 2 designates a flat plate-like blade body that is attached to each of the mounting surfaces 11, and is integrally provided with a cutting blade 21 that is at least the length of two threads. The cutting edge 21 of each blade body 2 is calculated and arbitrarily formed in accordance with the tooth profile of the drum-shaped worm wheel to be created. The flat blade body 2 in the embodiment is provided with an arbitrary number (three in the figure) of attachment holes 22 into which the attachment bolts 3 can be loosely inserted.

After applying one side of the flat plate-shaped blade body 2 to the mounting surface 11 of the arm μ1 and further applying the seat plate 4t to its outer surface, it is attached and detached by tightening it with any mounting bolt 3 such as a hexagon socket bolt. The mounting bolt 3 mentioned above is screwed into a female threaded hole 013 provided in the arm μ1. During this installation,
The base end (base end) of the flat plate-like blade body 2 has a mounting hole 22't, which is made larger in diameter than the bolt 3.
It is accurately positioned by making it abut against the receiving surface 12 of. Also,
The length direction of the blade 2, in other words, the hob axis! Positioning in the direction is performed using a cam rotatably mounted on the mounting surface 11.
This is done by Tsuk5. That is, both longitudinal ends of the blade body 2 are restrained and positioned between the wall surface 14 perpendicular to the mounting surface 11 and the cam piece 51 of the cam lock 5.

In the figure, reference numerals 6 and 6 are well-known external cutting tools placed on both sides of the flat blade body 1 and implanted in the arm μ 1, and are fixed by a cutting tool holder 7, a spacer 8, and a set screw 9, respectively.

According to the hourglass-shaped worm wheel gear cutting hob of the present invention described above, the following effects are achieved.

(1) Since the blade body 2 equipped with a plurality of cutting edges 21 mounted at least in the center of the arm μ1 is formed in a flat plate shape, that is, as a blade, it is not only easy to manufacture;
In addition to significantly improving the production efficiency of the hob as a whole,
A hob with extremely high precision can be provided.

(Because the tooth profile is created on a flat plate, pitch errors can be further reduced compared to conventional products.)

(3) Since creation by cutting into the wire is possible, a highly accurate blade body 2 can be produced, and furthermore, in this case, the No. 2 (relief surface) can be easily cut.

(4) Since the enveloping surface can be roughly formed, a fitting tooth surface can be easily obtained.

[Brief explanation of drawings]

Fig. 1 is a front view of a drum-shaped worm wheel gear cutting hob of the present invention, Fig. 2 is a side view thereof, and Fig. 3 is Fig. 1 m-1.
11 is a cross-sectional end view taken along line 11. FIG.

Claims (1)

[Claims] A mounting surface 1it is formed on the arm μ1 parallel to the hob axis l, and a flat blade body 2 having a cutting edge 21 equal to or more than two screw threads is removably fixed to the mounting surface 11. A drum-shaped worm wheel hob for gear cutting.