JP3342680B2 - Indexable cutting tool holder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a holder for a throw-away cutting tool, which is capable of electrically detecting the amount of wear at the cutting edge of the throw-away cutting tool and the occurrence of small cracks.

[0002]

2. Description of the Related Art Hitherto, there has been proposed a mechanism for automatically determining a tool life by detecting a wear amount of a cutting edge portion of a cutting tool.

FIG. 5 shows an example of such a detecting mechanism. The indexable cutting tool 60 provided with this mechanism detects a wear width at the limit of use. A wear sensor 61 formed of a thin conductive film circuit is formed at a position corresponding to the tool life width so that the wire is disconnected, and the tool life is automatically determined based on a change in the electric resistance. In this mechanism, when the indexable cutting tool 60 is worn during machining and finally proceeds to the wear sensor 61, the electric resistance starts to increase. When the maximum wear occurs, the circuit is disconnected. As described above, the width of wear is detected as a change in electric resistance, and the change in electric resistance is detected by a receiver to determine the tool life (Japanese Utility Model Laid-Open No. 3-120323). Therefore, the reliability is high, and the wear width (maximum wear amount) set as the service limit or the loss can be detected at the moment of the loss.

[0004]

However, in the prior art in which a detection mechanism is provided to the indexable cutting tool 60, the indexable cutting tool 60 has a flank 63 along the cutting edge 62 in use. Since the pair of ends of the wear sensor 61 and the lead wire 65 are connected to each other at a place where the chip is likely to contact during processing, such as 64, the discharge direction of the chip is changed by the lead wire 65 and the chip is entangled. Or the lead wire 65 may be broken.

In view of the problems of the prior art, the present invention makes it possible to electrically detect the limit of use and chipping by cooperating with a throw-away cutting tool having a wear sensor formed on the surface thereof, An object of the present invention is to provide a holder for a throw-away cutting tool that does not adversely affect the dischargeability and the like.

[0006]

In order to solve the above-mentioned problems, a holder according to the present invention is attached to a tip mounting portion having a pocket for fixing and holding a throw-away cutting tool provided with a wear sensor, and a tool post. A through-hole opening into the pocket, and an electrode member having a tip connected to the wear sensor is fixed in the through-hole in the holder body in an electrically insulated state. A holder for a cutting tool, wherein the electrode member comprises a contact probe in which an elastic body elastically supports a bar-shaped touch element, an insulating sleeve is inserted around the contact probe, and the contact probe is attached to the holder body by the insulating sleeve. The contact probe when the indexable cutting tool is fixed to the pocket. Rod-like probe is characterized in that it pressed against the wear sensor.

Further, the present invention is characterized in that, in such a holder, a conductive rubber material is attached to the tip of the rod-shaped touch element of the contact probe. in addition,
The present invention is characterized in that a lead wire fixed in a groove provided on an outer surface of the holder body is connected to a rear end of the contact probe.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of the present invention.

FIGS. 1 and 2 show a holder body 1 according to the present invention.
In the drawing, 2 is a throw-away cutting tool, 3 is a pocket for fixedly holding the throw-away cutting tool 2, 4 is a tip mounting portion having a pocket 3, and 5 is a shank portion to be attached to a tool post (not shown). , 7 are through holes opening into the pocket 3, and 8 is an electrode member (not shown in FIG. 1) fitted in the through hole 7.

The holder main body 1 has a shank portion 5 to be attached to a tool post (not shown), a tip mounting portion 4 at a tip end thereof, and a throw-away cutting in a pocket 3 provided in the tip mounting portion 4. In this configuration, the tool 2 is fixedly held.

The holder 1 is made of an alloy steel. The material of the holder 1 is alloy steel such as chromium-molybdenum steel, nickel-chromium steel, nickel-chromium-molybdenum steel, or C, Si, Mn, P and S in iron. There is an alloy steel based on a carbon alloy steel containing five elements to which chromium, tungsten, manganese, molybdenum, vanadium and the like are added.

As shown in FIG. 2 (a), this holder restrains the throw-away cutting tool 2 by using an L-shaped lever 9, and when the clamp bolt 10 is raised or lowered, one of the L-shaped levers 9 is moved. Is moved up and down.
As a result, the L-shaped lever 9 swings around the fulcrum, and the other end 9b of the L-shaped lever 9 causes the indexable cutting tool 2 to move.
The indexable cutting tool 2 placed on the sheet 11 is fixed to the holder 1 by pressing or releasing the hole wall 2b of the fixing hole 2a provided in the above.

The sheet 11 is a throw-away cutting tool 2
When a large loss occurs in the holder body 1
This is a protective member for preventing the distance from reaching. As a material of the sheet 11, a cemented carbide is mainly used.
If this material is softer than the indexable cutting tool 2, the sheet 11
There is a possibility that dents or deformations may occur in the cutting tool, causing the throw-away cutting tool 2 to rattle.

As shown in FIG. 1, the tip mounting portion 4 of the holder body 1 is provided with a pair of through-holes 7 opening into the pockets 3. An electrode member 8 that is in contact with the cutting tool 2 is fixed to the holder 1 in an electrically insulated state.

As an insulating method, an insulating sleeve 12 made of alumina ceramics or heat-resistant resin is fitted around the electrode member 8, and the insulating sleeve 12 is
Support and fix. The electrode member 8 and the insulating sleeve 1
2. The insulating sleeve 12 and the holder body 1 may be fixed by using an adhesive or by shrink fitting.

In the present embodiment, the electrode member 8 is constituted by a contact probe. The contact probe is made of a material such as brass or stainless steel, and has a configuration in which an elastic body (not shown) attached to the bottom of the hole of the bottomed cylinder elastically supports the rod-shaped contactor 8a. Then, the rod-shaped contactor 8a penetrates through the through hole 11a formed in the seat 11 from the seating surface 3a of the pocket 3 and a later-described wear sensor 21 provided on the throw-away cutting tool 2.
And a lead wire 13 is fixed to the lower end of the electrode member 8 by brazing or the like, and the lead wire 13 is connected to the resistance meter 14. As a result, the wear sensor 21 of the indexable cutting tool 2 is connected to the ohmmeter 14 via the electrode member 8.

By attaching a conductive rubber material (not shown) to the tip of the rod-shaped contact 8a of the electrode member 8, the adhesion between the rod-shaped contact 8a and the indexable cutting tool 2 is improved.
An electric signal can be stably detected.

A lead wire 13 fixed to the rear end of the electrode member 8 is inserted into a groove 15 provided on the outer surface of the holder body 1.
By fixing with a resin material (not shown),
Can be kept out of the way at all.
For the same purpose, a hole (not shown) for passing the lead wire 13 may be formed in the holder body 6.

Next, FIGS. 3 and 4 show the indexable cutting tool 2, in which 20 is a silicon nitride ceramic base material, and 21 is a conductive film circuit formed on the base material 20. FIG. A wear sensor, 22 is an end of the wear sensor 21;
Is the upper surface of the indexable cutting tool 2, 24 is the lower surface, 25
Is a flank, and 26 and 27 are cutting edges.

The indexable cutting tool 2 is of a negative type that can use the cutting edges 26, 27 on both upper and lower sides (23, 24).
Although eight nose portions 28 at corners can be used, one is an upper surface 23 and the other is a lower surface 24 for convenience.

FIG. 4 is an explanatory diagram showing the pattern of one of the wear sensors 21 in an easy-to-understand manner, and shows the pattern three-dimensionally by seeing through the inside of the indexable cutting tool 2. As shown in FIG.
4 has a pair of ends 22,
2 to a flank 25, and a cutting edge 26 which forms a boundary between the upper surface 23 and the flank 25 by traversing the flank 25.
And extends from there along this cutting edge 26.

The actual indexable cutting tool 2 is:
The wear sensor 21 having the ends 22 on the lower surface 24
And they reach the cutting edge 26 at the four nose portions 28 of the upper surface 23. On the other hand, the upper surface 23 is also the lower surface 24
The upper surface 23 has the ends 22 and 2
There are four wear sensors 21 provided with two, which reach the cutting edge 27 at four nose portions 28 of the lower surface 23. The indexable cutting tool 2 thus configured is mounted on the holder 1, and the cutting edge 2 in use shown in FIG.
The end portion 22 of the wear sensor 21 formed on the electrode 6 is pressed against the rod-shaped contactor 8a of the electrode member 8. Thereby, the wear sensor 21 is connected to the resistance meter 14 via the electrode member 8.

Then, the indexable cutting tool 2 is worn during machining, and the used cutting edge 26 of the wear sensor 21 is used.
When the wear finally reaches the width of the wear sensor 21 in the portion along the wear sensor 21, the wear sensor is disconnected, and the electric resistance becomes infinite. The width of the portion of the wear sensor 21 along the cutting edge 26 during use is substantially equal to the use limit wear width, and therefore, the wear at the moment when the wear progresses to the use limit wear width or the loss occurs is reached. The electric resistance of the sensor 21 becomes infinite. At this point, by connecting and setting the resistance meter 14 and a machine tool (not shown) so that the processing can be stopped, the use of the cutting edge 26 beyond the use limit or the loss of the cutting edge 26 is possible. Can be prevented from being used.

At this time, the wear sensor 21 and the electrode member 8
The contact portion is not exposed to the outside, and the lead wire 13 or the like does not impede the chip dischargeability.

The reason why the end portion 22 of the wear sensor 21 formed on the cutting edge 26 in use as described above and the rod-shaped contactor 8a of the electrode member 8 are pressed against each other is as follows. That is, if the contact between the wear sensor 21 and the rod-shaped contactor 8a of the electrode member 8 is weak, the two may be momentarily separated from each other due to the influence of vibration during machining. It is recognized that the wear has progressed or has been lost, and as a result, the machine tool may interrupt the cutting.

Although the embodiment of the present invention has been exemplified above, the present invention is not limited to the above embodiment. For example, the holder is not limited to using an L-shaped lever.
A clamper may be used.

The electrode member 8 is connected to the seating surface 3a of the pocket 3.
Not only those exposed from the side, but also those exposed from the lateral wall surface of the pocket 3 may be used.

[0028]

As described above, according to the present invention, there are provided a tip mounting portion having a pocket for fixing and holding a throw-away cutting tool provided with a wear sensor, and a shank portion mounted on a tool post. In the holder body, a through-hole that opens to the pocket is formed, and an electrode member whose tip is connected to the wear sensor in the through-hole is fixed in an electrically insulated state. In cooperation with the away cutting tool, reliable electrical detection of wear or loss of the cutting edge of the indexable cutting tool can be enabled. The electrode member is formed of a contact probe in which an elastic body elastically supports a bar-shaped touch element, an insulating sleeve is fitted around the contact probe, and the contact probe is supported and fixed to the holder body by the insulating sleeve. Accordingly, when the throw-away cutting tool is fixed to the pocket, the bar-shaped tentacle of the contact probe is pressed against the wear sensor, so that the contact probe can be supported and fixed to the holder body in an insulated state, and Since the end of the sensor and the rod of the contact probe can be pressed against each other, it is possible to prevent the end of the wear sensor from being separated from the rod of the wear sensor due to the influence of vibration during machining. Further, when a conductive rubber material is applied to the tip of the rod-shaped contact of the contact probe, the adhesion between the rod-shaped contact and the indexable cutting tool can be improved. Further, when a lead wire fixed in a groove provided on the outer surface of the holder main body is connected to the rear end of the contact probe, a contact portion between the conductive film circuit of the throw-away cutting tool and the electrode member of the holder becomes external. Because it is not exposed to chips, there is no hindrance to the discharge of chips by a lead wire or the like. Therefore, in the cutting process, a product defect is hardly generated, and high productivity can be improved.

[Brief description of the drawings]

FIG. 1 is a top view of a holder of the present invention with a seat mounted in a pocket.

FIG. 2 shows the holder of FIG. 1; FIG.
FIG. 3 is a diagram A, and FIG.

3A and 3B show a throw away cutting tool to be mounted on the holder of FIG. 1, wherein FIG. 3A is a bottom view and FIG. 3B is a side view.

FIG. 4 is a perspective view showing the arrangement of one wear sensor provided on the indexable cutting tool of FIG. 3;

FIG. 5 shows a prior art indexable cutting tool,
(A) is a perspective view of a state of being attached to a holder main body, (b)
FIG. 3 shows an upper surface of the throw-away chip, and FIG. 3C is an enlarged cross-sectional view showing a film configuration of the conductive film circuit.

[Explanation of symbols]

1. Holder body, 2. Indexable cutting tool,
2a ... fixed hole, 2b ... hole wall, 3 ... pocket, 3a
..Seat surface, 4 ··· Tip mounting part, 5 ··· Shank part, 7
..Through holes, 8 ·· Electrode members, 8a ·· Bar-shaped tentacles, 9 ·
· L-shaped lever, 10 · · clamp bolt, 11 · · sheet, 12 · · insulation sleeve, 13 · · lead wire, 14 ·
· Resistance meter, 15 · · Groove, 20 · · · Base material, 21 · · · Wear sensor, 22 · · · end, 23 · · · top surface, 24 · · · bottom surface, 2
5 · · · flank, 26, 27 · · cutting edge, 28 · · · nose

Claims (3)

(57) [Claims] 1. A through hole opening to said pocket in a holder body comprising a tip mounting portion provided with a pocket for fixing and holding a throw-away cutting tool provided with a wear sensor, and a shank portion attached to a tool post. And a holder for a throw-away cutting tool in which an electrode member whose tip is connected to the wear sensor in the through hole is fixed in an electrically insulated state. The contact probe is supported and fixed to the holder body by the insulating sleeve, whereby the indexable cutting tool is inserted into the pocket. Wherein the rod probe of the contact probe presses against the wear sensor when fixed. Holders of E Lee cutting tools. 2. The indexable cutting tool holder according to claim 1, wherein a conductive rubber material is attached to a tip of the rod-shaped contactor of the contact probe. 3. The indexable cutting tool according to claim 1, wherein a lead wire fixed in a groove provided on an outer surface of the holder body is connected to a rear end of the contact probe. Holder.