JP2774657B2 - Throwaway bytes - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a throw-away tool having a function of rotating a round indexable insert at a predetermined angle when a cutting blade is worn to find an unused blade and re-clamping. .

[Conventional technology]

The round indexable insert is required to be firmly clamped because it is mainly used for heavy cutting.

In addition, in order to eliminate economic loss, it is also required that the used area and the unused area of the cutting blade be accurately replaced.

However, the conventional round insert bit is as shown in FIG. 6, that is, the operator loosens the clamp A (lever-type clamp in the figure) at the time of changing the cutting edge, rotates the insert T by hand, and re-clamps. What you do is common.

Attempts to automate the clamping and indexing work,
For example, although this has already been done in JP-A-55-37221 and JP-A-55-37222, these still have problems to be solved.

[Problems to be solved by the invention]

Tools that rely on manual work for clamping and rotating inserts have poor workability and work efficiency, and lack the accuracy of indexing unused blades.

The automatic cutting tool disclosed in the above-mentioned publication has satisfactory performance with respect to the clamp, but has a disadvantage in the mechanism of the index and has low reliability. In addition, since the tip itself is provided with a serration for transmitting the rotational force, there is a disadvantage that a general-purpose tip cannot be used.

Therefore, the applicant of the present application has disclosed in Japanese Patent Application No. 1-311522 a taper engagement portion with a clamp rod while tilting in a clamping direction with a hydraulically operated clamp rod during clamping, that is, in a direction in which the tip is pressed against a side support seat. A technique has been proposed in which the tip is fixed to a lever shaft that is drawn into the shaft hole by the component force generated in the above, and the shaft is rotated by a fixed angle by a ratchet mechanism, thereby simultaneously preventing reverse rotation.

However, this tool requires the ratchet ratchet to be replaced when the cutting depth varies. That is, since the use length of the cutting edge varies greatly depending on the cutting depth of the round insert, the indexing pitch is shifted and the cutting edge is effectively used unless the ratchet wheel is replaced and the tip rotation angle per operation is adjusted. Can not expect.

An object of the present invention is to eliminate the above-mentioned problems.

[Means for solving the problem]

In order to achieve the above object, the present invention provides a rotary indexing tool for rotating a tip by a predetermined angle together with a lever shaft at the time of unclamping with a lever shaft. Then a lever is provided to push up the lever shaft. Further, a one-way clutch that connects the rotation indexing mechanism to the lower end of the lever shaft so that the output shaft can slide in the axial direction and cannot rotate, and a seat plate that rotates forward and backward at a fixed angle in conjunction with the movement of the clamp rod. A cam to be mounted on the seat plate, a mounting angle adjusting portion for the cam with respect to the seat plate, an input rod which is pushed by the cam to linearly move, and rotates the input wheel of the one-way clutch by an angle corresponding to the amount of movement, and a return spring for the rod. The input rod is pushed by the cam at the time of unclamping, and the linear momentum of the rod changes according to the mounting angle of the cam.

[Action]

When the lever is provided, the lever shaft is surely lifted during unclamping, and the friction between the lever and the seat surface is eliminated, so that the rotational resistance of the lever shaft is reduced.

The rotary indexing mechanism operates when the lever shaft is floating due to the retraction of the clamp rod, so that the indexing of a new cutting edge is smoothly performed without resistance.

In the rotation indexing mechanism, the linear momentum of the input rod changes according to the mounting angle of the cam, and the input wheel of the one-way clutch rotates at an angle corresponding to the momentum. Further, the output shaft of the one-way clutch rotates integrally when the input wheel rotates in one direction. Therefore, the rotation angle (rotation amount of the tip) of the lever shaft connected to the output shaft also changes depending on the mounting angle of the cam,
The adjustment of the mounting angle can cope with the change of the index angle accompanying the change of the cut depth.

In addition, the clamp of the tip is applied by the fact that the clamping force applied from the clamp rod is amplified by the lever ratio and transmitted to the tip, and the retracting of the lever shaft also generates a pressing pressure on the bottom of the tip. It is as strong and stable as.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

As shown in FIG. 1, a round indexable insert T
Is mounted on the tip seat 2 provided at the tip of the cutting tool body 1. A shaft hole 3 is opened in the bottom surface of the tip seat, and a lever shaft 4 is mounted in the hole. In the figure, the bottom of the chip is received by the bottom plate 5, and the shaft hole receives the tilting fulcrum of the lever shaft easily. Therefore, a replaceable sleeve 6 is attached to the bottom plate 5 and the tilting fulcrum of the lever shaft is set by the sleeve. However, these are only preferred factors.

The lever shaft 4 is tapered into the center hole of the chip, and is screwed into a screw hole (not shown) at the upper end.
And a sloping fulcrum 4b of a spherical surface in contact with the inner surface of the sleeve 6 and an inclined surface 4c protruding downward from the outer periphery of the lower end.

Reference numeral 7 denotes a clamp rod that pushes the inclined surface 4c to tilt the lever shaft 4 in the clamping direction during forward movement, and presses the tip T against the side surface 2a of the seat 2. When this rod advances, the slope 4c
A downward component force is generated in the engaging portion with the lever, and the lever shaft 4 is pulled into the shaft hole by this force. The clamp rod 7 is moved forward and backward by a hydraulically operated piston 8. Numeral 9 is a return stroke adjusting screw of the piston, and constitutes a clamp mechanism together with 7, 8. Note that two pistons 8 are provided in series to increase the thrust. This is an effective structure for reducing the size of the main body, but the serial arrangement of a plurality of pistons is not an essential requirement of the present application.

12 is the oil introduction port, the upper one is the front chamber of the cylinder
On the lower side, it leads to the rear chamber 11.

Reference numeral 13 denotes a lever rotatably attached to the main body using a horizontal support shaft. This lever 13 is connected to the clamp rod 7
At the time of retreat, one end is pushed down by the rod 7, whereby the other end is lifted and pushes up the lever shaft 4 from below.

Reference numeral 15 denotes a chip rotation indexing mechanism. This mechanism 15
A one-way clutch 16 supported by the main body and installed below the lever shaft 4, a seat plate 17 having an outer peripheral pivot shaft connected to the crank rod 7, and a cam 19 with an adjustment scale fixed to the seat plate with bolts 18. An input rod 20 is slidably supported by the main body and one end of the input rod is in contact with a cam, and a spring 21 that applies a restoring force to the rod to constantly contact the rod with the cam.

The one-way clutch 16 is a well-known clutch in which a ball or a roller is fitted into a ramp groove between an input wheel 16a and an output shaft 16b, and the input wheel is in one direction (the direction of the arrow in FIG. 4). The output shaft rotates together when it rotates.

The other end of the input rod 20 is connected to an input wheel 16a of a clutch in a link shape that can swing in a horizontal plane. The output shaft 16b of the clutch is connected to the lower end of the lever shaft 4. The output shaft 16b for the lever shaft 4
It is necessary to transmit the rotational force while allowing the lever shaft to move up and down, so that it is slidable in the axial direction and relative rotation is not possible. Also, in order to eliminate interference when the lever shaft is tilted, an appropriate play is generated between the output shaft 16b and the hole on the lever shaft side that receives the output shaft 16b.

Reference numeral 14 denotes a spring contracted between the lever shaft 4 and the output shaft 16b. This spring prevents the lever shaft from being retracted by shock. In addition, an appropriate rotation resistance is given to 16b, so that the disengagement of the clutch at the time of reverse rotation of the input wheel 16a is improved. Therefore, it is preferable.

 The operation of the exemplary byte is described below.

When hydraulic pressure is applied to the front chamber 10 of the cylinder, the piston 8 moves and the clamp rod 7 moves backward, and the engagement between the rod 7 and the lever shaft 4 is released. At the position where the rod 7 is slightly retracted, the lever 13 is actuated to push the lever shaft 4 up to the position shown in FIG. 5 (the bite shown in FIG. 5 also lifts up together).
The index is ready. Thereafter, the rod 7 further retreats and the pushing of the input rod 20 by the surface of the cam 19 is started, the input wheel 16a rotates, and this rotational force is transmitted to the lever shaft 4 via the output shaft 16b. Therefore, the lever shaft rotates by the same angle as the input wheel, and the cutting edge of the tip is replaced.

When the supply of hydraulic pressure is switched to the rear chamber 11 and the clamp rod moves forward, the cam 19 rotates in the reverse direction and the input rod 20 returns, but at this time, the input wheel and the output shaft No power transmission occurs between them, so that the newly indexed cutting edge is held at the index point.

Here, the rotation angle θ of the seat plate 17 that rotates in conjunction with the movement of the clamp rod 7 is always constant if the stroke l of the rod 7 is constant. However, when the mounting angle of the cam 19 with respect to the seat plate 7 is adjusted, the invalid rotation amount from the start of rotation to the start of pushing the input rod changes. Since the linear momentum of the input rod increases as the amount of invalid rotation of the cam decreases, the indexing angle of the cutting edge is adjusted using this.

Next, as the clamp rod 7 moves forward, the lever 13
Is disengaged, but at this time, since the spring 14 has received the lever shaft 4, the lever shaft is still floating.
That is, the lever shaft is drawn into the shaft hole 3 after the clamp rod 7 starts pressurizing the slope 4c, and simultaneously tilts. Due to this tilt, the clamping force applied from the clamp rod 7 is amplified and transmitted to the chip T. The chip is pressed against the seat side surface 2a by this strong force, and the clamping force acts on the bottom surface by the retraction, so that the chip is firmly fixed. Is more than unclamped,
A series of operations of rotating indexing and re-clamping of the cutting edge are completed.

〔effect〕

As described above, according to the present invention, since the lever shaft is tilted in the clamp direction by the clamp rod and simultaneously pulled down to generate the clamp force with the amplified force, a strong clamp is guaranteed.

In addition, since the indexing angle can be adjusted by devising a rotary indexing mechanism for the cutting edge, even if the cutting amount changes, the indexing angle can be adjusted to an angle according to the cutting amount without replacing parts. It can be changed, and the entire area of the cutting blade can be used without waste and economical loss can be eliminated.

Further, since the chip to be used is a general-purpose chip, it is economical in this aspect as well.

[Brief description of the drawings]

1 is a cross-sectional view showing one embodiment of the present invention, FIG. 2 is a plan view thereof, FIG. 3 is a bottom view of a state where a lower cover is cut away, FIG. 4 is a plan view of a rotary indexing mechanism, FIG. 5 is a sectional view of a main part at the time of unclamping, and FIG. 6 is a partial sectional view showing an example of a conventional cutting tool. 1 ... tool body, 2 ... tip seat, 2a ... seat side surface, 3 ... shaft hole, 4 ... lever shaft, 4a ... set screw, 4b ... tilting fulcrum, 4c ... slope, 5 ... Base plate, 6 ... Sleeve, 7 ... Clamp rod, 8 ... Piston, 9 ... Return stroke adjusting screw, 10 ... Front chamber of cylinder, 11 ... Rear chamber of cylinder, 12 ... Introducing port, 13 ... ... Lever, 14 ... Spring, 15 ... Rotating indexing mechanism, 16 ... One-way clutch, 16a ... Input wheel, 16b ... Output shaft, 17 ... Seat plate, 18 ... Bolt, 19 ... Cam , 20 ... Input rod, 21 ... Spring.

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Shunsuke Uchida 5-1-1109 Shimaya, Konohana-ku, Osaka-shi, Osaka Sumitomo Metal Industries, Ltd. Steelworks (56) References JP-A-62-292303 (JP, A) JP-A-55-37221 (JP, A) JP-B-55-27802 (JP, B2) (58) Fields investigated (Int. Cl. ⁶ , DB name) B23B 27/00 B23B 27/16

Claims (1)

(57) [Claims] 1. A lever shaft, which is inserted into a shaft hole opened in a seat bottom surface of a tip mounting portion and is screwed at a top end thereof with a round throw-away tip, and the lever shaft is moved forward by a hydraulically operated clamp rod when the rod is advanced. A tilt-away tool that pulls into the shaft hole while tilting to generate a tip clamping force and rotates the tip with the lever shaft by a predetermined angle with the rotation indexing mechanism during unclamping. A lever that pushes up the shaft is provided. Furthermore, the rotation indexing mechanism has a one-way clutch that connects the output shaft to the lower end of the lever shaft so that it can slide in the axial direction and cannot rotate, and a fixed angle in conjunction with the movement of the clamp rod. A seat plate that rotates forward and backward, a cam that is mounted on this seat plate, a mounting angle adjustment unit for the cam with respect to the seat plate, and a one-way An input rod for rotating the input wheel by an angle corresponding to the momentum and a return spring for the rod so that the input rod is pushed by the cam at the time of unclamping so that the linear momentum of the rod changes according to the mounting angle of the cam. A throwaway byte characterized by doing.