JP5650981B2 - Turning tools and machine tools using them - Google Patents

Description

  The present invention relates to a turning tool such as a face milling cutter and a corner milling cutter, and a machine tool using the same, which enables suction and recovery of chips without using a casing covering the outer periphery of the cutter body.

  In order to smoothly recover chips generated by a milling tool such as a milling cutter, the outer periphery of the tool is covered with a casing, a conveying airflow is generated inside the casing, and the chips are placed on the airflow to form a casing. A chip recovery device that guides to a side discharge port and recovers via a duct is proposed in Patent Document 1 below.

  In addition, for cutting tools that are used by holding the tool with the tool holder and drawing it into the spindle of the machine tool with a draw bar that penetrates the shank of the tool holder through the spindle, a chip lead-out passage is provided in the axial center of the tool body. In some cases, the lead-out passage, the tool holder and the suction hole in the draw bar are sucked and collected.

JP 2000-126976 A

  As described above, a cutting tool of a type in which a tool holder is drawn into a main spindle of a machine tool with a draw bar and a shank is gripped with the tool holder is provided with a chip discharge passage in the axial center of the tool body, and the discharge passage is provided as a tool. The chips can be sucked and collected by communicating with suction holes provided in the holder, the draw bar, and the main shaft.

  However, a milling tool that is mounted on the main spindle of a machine tool using a cutter arbor or the like inserts a fitting shaft into the center mounting hole of the cutter body, and a center bolt (clamping bolt) for fixing the tool to the fitting shaft. Therefore, the mounting hole cannot be used as a chip outlet passage.

  Therefore, as proposed in the above-mentioned Patent Document 1 and the like, chips are collected by covering the outer periphery of the cutter body with a casing, but this structure increases the size of the apparatus because of the casing.

  In addition, there are cases where the casing becomes an obstacle and is subject to machining regulations. In corner cutting, the casing is opened to a position where there is no hindrance to machining in order to avoid the machining regulation. There is a problem that efficiency decreases.

  The present invention relates to a cutting tool and a machine tool using the same, in order to avoid an increase in the size of the apparatus and to ease processing restrictions, for chips generated by milling without providing a casing covering the outer periphery of the cutter body. It is an issue to enable efficient collection.

In order to solve the above-mentioned problems, in the present invention, a cutter body having an axially penetrating attachment hole in the center portion, and the front end of the cutter body and the front surface and the outer peripheral surface of the cutter body are opened to the two surfaces. In a turning tool having a chip pocket provided and an insert seat facing the chip pocket, and a cutting insert mounted on the insert seat,
A chip discharge hole is provided inside the cutter body, one end of which is opened in the chip pocket and the other end is opened in the back surface of the cutter body, and is further fixed to the cutter body to block the opening of the chip pocket. a cover, a gap for scrap lead cut substantially between cutting edge portion of the cutting insert and its cover is provided, the cutting chip discharging the chips flowing from the gap for the chip into the chip pocket It is possible to withdraw and collect via holes ,
The cover has an L-shape when viewed from the end, and the cover is fixed to the cutter body from either the outer peripheral side or the front side of the cutter body .

  The substantial cutting edge portion of the cutting insert here refers to a region actually involved in cutting among the cutting edge ridge line of the cutting insert.

Preferred forms of this rolling tool are listed below.
(1) The entrance area of the gap formed between the cover and the cutting insert is set to be not more than twice the cross-sectional area in a cross section perpendicular to the hole axis of the chip discharge hole.
(2) The chip discharge hole is inclined so that the opening of the hole to the chip pocket is in front of the tool in the forward direction with respect to the opening of the back of the cutter body.
(3) The chip discharge hole is inclined such that the opening of the hole to the chip pocket is located behind the opening of the back of the cutter body in the forward direction of the tool, and the chip discharge hole A part of at least a part of the opening to the chip pocket is arranged at a position facing the rake face of the cutting insert.
(4) The cover is detachable from the cutter body.
(5) The chip discharge holes are provided in the same number as the number of chip pockets corresponding to each of the plurality of chip pockets provided at intervals in the circumferential direction.

  The rolling tool according to the present invention is mounted on a spindle of a machine tool using an adapter that holds the tool and a draw bar that draws a shank of the adapter into the spindle. As the draw bar provided through the main shaft, a draw bar having a suction hole penetrating in the axial direction is used.

  The adapter has a suction passage communicating with a suction hole inside the draw bar, and the suction passage is opened on the front surface of the main body.

  Then, the opening of the suction passage formed on the front surface of the main body of the adapter is abutted with the opening to the rear surface of the cutter body of the chip discharge hole so that the chip discharge hole is communicated with the suction hole in the draw bar, and suction is performed. Connect the suction port of the hole to the dust collector to configure the chip recovery device. The present invention also provides a machine tool to which the chip recovery device is attached.

  The cutting tool according to the present invention guides chips from the chip pocket surrounded by the cover to the back surface of the cutter body via a chip discharge hole provided in the cutter body. Therefore, it is not necessary to cover the outer periphery of the cutter body with the casing, and the enlargement of the apparatus due to the casing installation is avoided.

  Moreover, since there is no casing, the problem of the chip | tip collection efficiency fall resulting from opening a casing large in a cornering process does not arise, and a process control is eased.

  The chips guided to the back surface of the cutter body are discharged to the dust collecting section through a suction passage formed in the adapter and a suction hole provided in the adapter drawing drawer.

The side view which shows the 1st form of the rolling tool of this invention Front view of the turning tool of FIG. Sectional view along line XX in FIG. Rear view of the turning tool in FIG. 1 is a perspective view of the turning tool of FIG. 1 is a perspective view showing the turning tool of FIG. 1 with a cover, a locator, and a cutting insert removed at one place. (A) Perspective view showing part of edge of gap forming portion of cover, (b) Cross-sectional view along line YY in FIG. 7 (a) The side view which shows an example of the adapter used in combination with the cutting tool of this invention Front view of the adapter of FIG. Sectional drawing which shows the spindle apparatus of the machine tool which uses the turning tool of this invention Side view showing the second embodiment of the turning tool of the present invention Front view of the turning tool of FIG. Sectional drawing along the ZZ line of FIG. FIG. 11 is a perspective view of the turning tool of FIG.

  Embodiments of a rolling tool according to the present invention will be described below with reference to FIGS.

  FIGS. 1-7 has shown the example (1st form) which applied this invention to the corner milling cutter. The rolling tool 1 according to the first embodiment includes a cutter body 2, a locator 3 removably attached to the cutter body 2, a cutting insert 4 held by the locator, and a shaft of a cutting edge 4a of the cutting insert 4. The blade run-out adjusting mechanism 5 for adjusting the directional position and the cover 6 are combined.

  The cutter body 2 has a mounting hole 7 (see FIGS. 2 to 6) penetrating in the axial direction at the center. Moreover, the chip | tip pocket 8 (refer FIG. 6) open | released in two surfaces, the front surface 2a of the body, and the outer peripheral surface 2b, is provided in the front-end | tip outer periphery. Further, a chip discharge hole 9 is provided inside the cutter body 2 such that one end 9a shown in FIGS. 1 and 6 is opened in the chip pocket 8 and the other end 9b is opened in the back surface 2c.

  The locator 3 is assembled in a holding groove 2 e provided on the outer periphery of the cutter body 2 using a locator mounting bolt 10. In the illustrated tool, an insert seat 11 is provided in the locator 3, and a clamp screw 12 (see FIG. 3) through which the cutting insert 4 is passed through the center mounting hole of the insert seat 11 is used. Is fixed.

  The insert seat 11 may be provided directly on the cutter body 2 with the locator 3 omitted. However, in order to enable replacement regeneration of the damaged insert seat, the insert seat 11 is provided on the locator 3 using the locator 3 here. Yes.

  Although the cutting insert 4 illustrated the chip | tip of the blade-tip exchange type, it is not limited to this. Any cutting tool provided with one or more cutting edges may be used.

  A plurality of chip pockets 8 are provided at intervals in the circumferential direction, and an insert seat 11 is provided at the rear of each chip pocket 8 in the cutter rotating direction so as to face the chip pocket 8. The cutting inserts 4 are respectively attached to the two. The chip discharge holes 9 are individually provided in the respective chip pockets so as to correspond to the respective chip pockets 8.

  The blade run-out adjusting mechanism 5 is a well-known mechanism that adjusts the axial position of the cutting edge of the cutting insert 4 by screwing the adjusting bolt 5a into the cutter body 2 and abutting the locator 3 on the head of the adjusting bolt 5a. It is provided according to.

  The cover 6 is provided for the purpose of closing both the body outer peripheral side and the front side opening of the chip pocket 8 and has an L-shape in end view. The cover 6 is detachably fixed to the cutter body 2 using screws 13. A gap 14 for introducing chips (see FIGS. 1 and 5) is provided between the cover 6 and the cutting edge of the cutting insert 4 (the portion of the cutting edge that substantially functions as a cutting edge). It has been.

  The gap 14 is set to a size that allows the generated chips to pass therethrough. For the prototype tool, the gap 14 was preferably about 5 mm. Under general processing conditions in milling, for example, cutting: 6 mm or less, feeding: 0.5 mm / min or less, usually a maximum of about 4.5 mm in length and about 0.2 mm in width Is generated. The preferred dimensions described above are one size larger than the maximum size of chips and allow the generated chips to pass through without difficulty.

  The total area of the entrance of the gap 14 is preferably not more than twice the cross-sectional area in the cross section perpendicular to the hole axis of the chip discharge hole 9. If the total area of the entrance of the gap 14 is larger than necessary, the suction force at the position of the gap 14 decreases. The size of the gap is compared with the cross-sectional area of the chip discharge hole 9 because the cross-sectional area of the chip discharge hole 9 is smaller than the cross-sectional area of the chip pocket 8 and the cross-sectional area of the chip discharge hole 9 is. This is because the amount of airflow that is sucked in depends on the flow rate.

  If the cover 6 forms the chamfered part 6c shown in FIG. 7 in the edge of the location which forms the clearance gap 14, it will become difficult for chips to be caught.

  As shown in FIG. 1, the chip discharge hole 9 has a direction in which the opening to the chip pocket 8 is in the forward direction of the tool forward than the opening to the back surface 2 c of the cutter body (here, this is the positive direction). Or the direction opposite to that {the direction in which the opening to the chip pocket 8 is located behind the opening to the back surface 2c of the cutter body in the forward direction of the tool (this is referred to as the negative direction). Can be considered)}.

  In the chip discharge hole 9 inclined in the positive direction, chip discharge is assisted by the rotation of the tool, so that the flow of the chip becomes smooth. Further, the chip discharge hole 9 inclined in the negative direction is a position where at least a part of the opening to the chip pocket 8 faces the rake face of the cutting insert 4 (position where the suction port approaches the cutting insert 4). Therefore, the suction force acting on the cutting part can be increased, which also improves the efficiency of collecting chips.

  The chip discharge hole 9 does not need to be a straight hole. A hole bent in the middle of the restriction may be used, and there may be a case where the hole must be bent from the viewpoint of installation space and workability.

  The cover 6 is preferably detachable. The cutting insert 4 can be attached / detached by removing the locator 3 from the cutter body 2, but if the cover 6 is removed, the cutting insert 4 can be attached / detached without removing the locator 3. This eliminates the need for readjustment of the blade runout that is necessary when the locator 3 is attached or detached each time.

  Further, it is preferable to form the chamfered portion 6c shown in FIG. 7 at the edge of the portion where the gap 14 of the cover 6 is formed because it is difficult for chips to be caught.

  The rolling tool 1 configured as described above is mounted on the spindle of a machine tool using the adapter 15 shown in FIGS.

  The illustrated adapter 15 includes a fitting shaft 15b at the center of the tip of the main body 15a, and further includes a key 15c that transmits torque to the cutting tool around the fitting shaft 15b. The fitting shaft 15b is inserted into the mounting hole 7 at the center of the cutter body, and the key 15c is engaged with a key groove 2d (see FIGS. 3 and 4) formed on the back surface of the cutter body. The rolling tool 1 is fixed by tightening the front surface with the center bolt 16 of FIG. 10 screwed into the fitting shaft 15b.

  The adapter 15 has a suction passage 17 opened in the front surface of the main body portion 15a. The opening of the suction passage 17 on the front surface of the main body portion corresponds to the opening of the chip discharge hole 9 provided in the cutting tool 1 to the cutter body rear surface 2c, and the adapter 15 is attached to the adapter 15. When this is done, the opening of the suction passage 17 and the opening of the chip discharge hole 9 to the rear surface of the cutter body are brought into contact with each other so that the chip discharge hole 9 is connected to the suction passage 17.

  The adapter 15 is attached to the spindle 21 of the machine tool using a draw bar 23 as shown in FIG. Reference numeral 20 in FIG. 10 denotes a spindle device of a machine tool. The main shaft 21 is rotatably supported by the main shaft head 22 and is rotationally driven by a drive source (not shown).

  A draw bar 23 is provided inside the main shaft 21 so as to penetrate the main shaft 21. The draw bar 23 is pushed and pulled by the drawing device 24. The pull-in device 24 is a well-known device that uses a fluid-actuated cylinder actuator as a drive source. With this draw bar 23, the shank 15 d of the adapter 15 is drawn into the main shaft 21.

  The draw bar 23 has a suction hole 25 penetrating in the axial direction. The suction passage 17 provided in the adapter 15 communicates with the central hole of the main body 15a, and the tip of the draw bar 23 is inserted inside the adapter shank 15d so that the chip discharge hole 9 inside the cutter body is formed. It communicates with the suction hole 25 inside the draw bar.

  A duct (not shown) of a dust collector is connected to the suction port 25a of the suction hole 25 opened at the upper end of the spindle head 22. As a result, a chip collection device is configured in which the chip discharge hole 9 inside the cutter body, the suction passage 17 inside the adapter, and the suction hole 25 inside the draw bar are used as a chip discharge path, and surrounds the outer periphery of the cutter body 2. It is possible to efficiently collect chips generated by milling without using a housing.

  FIGS. 11-14 has shown the 2nd form of the rolling tool of this invention. In the second embodiment, the present invention is applied to a front milling cutter having a lead angle of 45 °. In the rolling tool 1 of the second form, the shape of the cutter body 2 is different from that of the first form. Further, the cover 6 covering the opening of the chip pocket 8 is constituted by two members, a main cover 6a and a ring-shaped auxiliary cover 6b, and further, the chip discharge hole 9 provided in the cutter body 2 will be described first. The holes are inclined in the negative direction, and these configurations are different from those of the first embodiment.

  The main cover 6a has a shape that closes the opening of the chip pocket 8 on the outer peripheral side of the cutter body and the opening of the inclined surface on the distal end outer diameter side. When the main cover 6a is in its shape, the chip pocket 8 cannot close the opening of the portion opened to the recess on the front surface of the cutter body. Therefore, the disc-shaped auxiliary cover 6b is additionally provided, and the cutter body 2 is formed by the auxiliary cover 6b. The opening of the concave portion on the front surface of the front is closed.

  A gap 14 for introducing chips is provided between the main cover 6 a and the cutting edge 4 a (substantially functioning as a cutting edge) of the cutting insert 4.

  In the cutting tool 1 of the second embodiment, air leakage from the concave side of the front surface of the cutter body with respect to the chip pocket 8 is suppressed by installing the auxiliary cover 6b. Therefore, although not as much as the first form, the rolling tool 1 of the second form also exhibits an excellent dust absorption function.

  In addition, since the other structure of a 2nd form and the usage method of this tool do not change with a 1st form, description is abbreviate | omitted.

The cutting tools of the following invention products 1 to 3 were made as trial products.
・ Invention 1: Corner cutting milling cutter with outer diameter of 100 mm and gap 14 of about 45 mm ² shown in FIGS. 1 to 6, axial rake: + 24 °, radial rake: + 15 ° 20 ′
・ Invention 2: Corner cutting milling cutter with 6-blade outer diameter φ100 mm and gap 14 of about 100 mm ² shown in FIGS. 1 to 6, axial rake and radial rake are the same as invention 1 ・ Invention 3 : Front blade mill cutter with outer diameter of 100 mm, gap 14 area of about 48 mm ² , lead angle 45 °, axial rake: + 20 °, radial rake: −15 °

  The area of the gap 14 in the above is an area projected on a plane.

Each of the chip discharge holes inside the cutter body provided in the cutting tools of Inventions 1 to 3 has a diameter of 10 mm, and an area in a cross section perpendicular to the axis is 78.540 mm ² .

Next, the workpiece of FC250 was cut under the following conditions using the rolling tools of Inventions 1 to 3.
Cutting conditions for Inventions 1 and 2
Rotational speed: 250 min ⁻¹ , feed: 150 mm (0.1 mm / min), cutting depth: 6 mm, cutting width: 40 mm, workpiece removal amount: 92 cc / min
Cutting conditions for Invention 3
Rotation speed: 320 min ⁻¹ , feed: 576 mm (0.3 mm / min), incision: 3 mm, cutting width: 80 mm, workpiece removal amount: 138 cc / min

  As a result of examining the dust absorption rate (recovery amount / removal amount) of the chips in this processing, the recovery rate of Inventions 1 and 2 was 99%, and the recovery rate of Invention 3 was 91%.

  In this test result, the effectiveness of the rolling tool according to the present invention (which enables efficient recovery of chips without a casing) often appears.

DESCRIPTION OF SYMBOLS 1 Turning tool 2 Cutter body 2a Front surface 2b Outer peripheral surface 2c Back surface 2d Keyway 2e Holding groove 3 Locator 4 Cutting insert 4a Cutting edge 5 Blade run-out adjustment mechanism 5a Adjustment bolt 6 Cover 6a Auxiliary cover 6c Chamfering part 7 Installation hole 8 Chip pocket 9 Chip discharge hole 9a One end of hole 9b The other end of hole 10 Locator mounting bolt 11 Insert seat 12 Clamp screw 13 Screw 14 Clearance 15 Adapter 15a Body 15b Fitting shaft 15c Key 15d Shank 16 Center bolt 17 Suction Passage 20 Spindle device 21 Spindle 22 Spindle head 23 Drawbar 24 Pull-in device 25 Suction hole 25a Suction port

Claims (7)

A cutter body (2) having a mounting hole (7) penetrating in the axial direction in the center, and the front end (2a) and the outer peripheral surface (2b) of the cutter body are opened at the outer periphery of the cutter body (2). In a cutting tool having a chip pocket (8) provided and an insert seat (11) facing the chip pocket, the cutting seat (4) being mounted on the insert seat (11),
A chip discharge hole (9) having one end opened in the chip pocket (8) and the other end opened in the back surface (2c) of the cutter body is provided in the cutter body (2), and the cutter body A cover (6) fixed to (2) and closing the opening of the chip pocket (8);
A chip introduction gap (14) is provided between the cover (6) and the substantial cutting edge of the cutting insert (4), and flows into the chip pocket (8) from the gap (14). The chip can be sucked and collected via the chip discharge hole (9),
The cover (6) is L-shaped when viewed from the end, and the cover (6) can be fixed to the cutter body (2) from either the outer peripheral side or the front side of the cutter body. A turning tool.   The entrance area of the gap (14) formed between the cover (6) and the cutting insert (4) is less than twice the cross-sectional area in the cross section perpendicular to the hole axis of the chip discharge hole (9). The rolling tool according to claim 1, wherein   The chip discharge hole (9) is inclined so that the opening to the chip pocket (8) of the hole is in the forward direction of the tool forward than the opening to the back surface (2c) of the cutter body. The rolling tool according to claim 1 or 2, wherein   The chip discharge hole (9) is inclined so that the opening to the chip pocket (8) is behind the opening to the back surface (2c) of the cutter body in the forward direction of the tool. The rolling tool according to claim 1 or 2, wherein at least a part of an opening of the chip discharge hole to the chip pocket is arranged at a position facing the rake face of the cutting insert (4). .   The cutting tool according to any one of claims 1 to 4, wherein the cover (6) is detachable from the cutter body (2).   The number of chip discharge holes (9) is provided in the same number as the number of chip pockets corresponding to each of the plurality of chip pockets (8) provided at intervals in the circumferential direction. The rolling tool according to any one of 5. A main shaft (21) that is rotationally driven by a drive source, the rolling tool (1) according to any one of claims 1 to 6, and a fitting shaft (15b) provided at the center of the tip of the main body (15a). An adapter (15) that is inserted into a mounting hole (7) at the center of the cutter body, and a center bolt (16) is screwed into the fitting shaft (15b) to fix and hold the rolling tool (1), and the main body portion A drawbar (23) for drawing a shank (15d) integral with (15a) into the main shaft (21) and fixing the adapter (15) to the main shaft, and a drawing-in device (24) for the drawbar;
The draw bar (23) provided through the main shaft (21) has a suction hole (25) penetrating in the axial direction inside,
The adapter (15) has a suction passage (17) communicating with the suction hole (25) inside the draw bar, and the suction passage (17) closely contacts the back surface of the cutter body (2). An opening is made in the front surface of the main body (15a), and the opening is abutted with an opening to the cutter body back surface (2c) of the chip discharge hole (9) so that the chip discharge hole (9) is inside the draw bar. Machine tool constituted by connecting the suction port (25a) of the suction hole (25) to a dust collector.

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