CN101357462B - Rotary cutting tool - Google Patents

Abstract

A rotary cutting tool includes a flute, a blade assembly and a wedge. The groove is formed in the outer periphery of the tool body along the axial direction of the tool body, and has side walls inclined relative to each other such that the width between the side walls decreases toward the opening of the groove. The blade assembly includes a blade and a blade retaining plate, the blade is removable and movable relative to the blade retaining plate. Additionally, the blade assembly and wedge can be received in the slot such that the cutting portion of the blade protrudes from the opening. Additionally, the blade assembly is wedged in the slot when the tool body is rotated.

Description

rotary cutting tool

technical field

The present application relates to a plate-like knife, and more particularly to a rotary cutting tool having a plurality of separately replaceable plate-like knife on each outer peripheral surface of a cylindrical body.

Background technique

A rotary cutting tool having a disposable (replaceable blade) type insert is known (see, for example, Japanese Utility Model Publication No. 02-28014). The rotary cutting tool has a replaceable T-shaped backing bar configured to engage the T-shaped groove and a replaceable centrifugal wedge that utilizes the interference of the backing bar to secure the blade.

However, with regard to the rotary cutting tool according to the above reference, the cutting edge is not sharpened in order to be reusable if the edge has worn. In addition, the concave portion of the blade and the convex portion of the fixing member engage to fix each other in position. Therefore, when the cutting edge wears out, the insert must be replaced to maintain the cutting radius. When the cutting edge is sharpened, the position of the cutting edge changes according to the amount of sharpening, so that since each cutting edge cannot move in the radial direction, the cutting radius becomes smaller. Therefore, there arises a problem that the set position of the rotation axis needs to be finely adjusted in scale.

Thus, the prior art requires that the cutting edge of the plate-like insert is always fixed in the initial position after the cutting edge has been sharpened, in order to use the same cutting edge for a longer time than usual, thereby reducing their running costs. Another need is to save the time required to set up plate-like blades.

Contents of the invention

According to a first aspect of the invention, a rotary cutting tool includes a flute, a blade assembly and a wedge. Also, a plurality of the above-mentioned components may be used. Each groove is provided on the outer periphery of the cylindrical main body of the rotary cutting tool along the axial direction of the main body, and the side walls of the grooves are inclined relative to each other such that the width between the side walls decreases toward the opening of the groove. The blade assembly includes a plate-shaped blade and a blade holding plate, and the plate-shaped blade is detachable from the blade holding plate and movable in a radial direction to adjust a cutting radius of the blade. Both the blade assembly and the wedge can be received in corresponding slots such that the cutting edge of the plate-like blade protrudes from the opening. Furthermore, when the cylindrical body is rotated, the blade assembly is locked in the groove by the wedge under centrifugal force.

According to the first aspect, the plate-like blade is detachable and movable relative to the blade holding plate of the blade assembly. If the position of the leading edge of the insert changes due to sharpening of the insert, the cutting radius can be adjusted by moving the insert in the radial direction. Therefore, the same plate-shaped insert can be used for a longer period of time than the insert of a conventional cutting tool, and since the insert can be sharpened many times, the running costs required for using the device can be reduced. In addition, since the cutting radius can be adjusted by moving the cutting edge to the initial position, the cutting accuracy of the rotary cutting tool can be maintained.

Also, it is preferable that the blade holding plate is larger than the plate-shaped blade so that the plate-shaped blade can be detached and moved.

Regarding the second aspect of the present invention, the rotary cutting tool according to the first aspect further includes a holding member configured to hold each wedge within a predetermined range in the corresponding groove.

According to the second aspect, each holding member holds the wedge within a predetermined range. The wedge is held by the holding member when the blade assembly is detached during replacement of the plate-like blade for sharpening or the like, so that the retaining wedge is not required when the blade assembly is mounted again. Therefore, the blade assembly can be mounted quickly.

Regarding a third aspect of the present invention, the plate-shaped insert of the rotary cutting tool according to the first and second aspects further includes an engaging member. Each engagement member couples the plate-like blade with the blade holding plate or a constituent part of the rotary cutting tool in a manner that allows the blade-like blade to move.

According to the third aspect, the engagement member couples the plate-shaped blade with the blade holding plate. Alternatively, the engagement member couples the plate-like insert with a constituent part of the rotary cutting tool. The engaging part is configured to allow the plate-shaped blade to move, but prevent the plate-shaped blade from coming off due to centrifugal force even if the plate-shaped blade is separated from the blade assembly.

According to the invention, the blade assembly allows the plate-like blade to move relative to the blade holding plate. Therefore, since the front edge position can be adjusted when the cutting edge has been sharpened, the same plate-shaped insert can be used for a longer period of time than that of a conventional rotary cutting tool. Also, since the holding member holds the wedge within a predetermined range, the time required for setting can be reduced.

Description of drawings

1 is an exploded perspective view of a rotary cutting tool according to an embodiment of the present invention;

Figure 2 is an exploded perspective view of the wedge;

Fig. 3 is a perspective view of the wedge after installation;

Figure 4 is an exploded perspective view of the blade assembly;

Fig. 5 (A) is the perspective view of blade assembly;

Figure 5(B) is a sectional view of the blade assembly shown in Figure 5(A);

6 is a perspective view showing the process of installing the blade assembly on the rotary cutting tool;

Figure 7 is a perspective view of the installed blade assembly;

Figure 8 is a perspective view of a rotary cutting tool;

Figure 9 is a side view of a rotary cutting tool;

Figure 10(A) is a sectional view of the rotary cutting tool taken along line X-X in Figure 9;

Figure 10(B) is an enlarged cross-sectional view of the rotary cutting tool shown in Figure 10(A);

11 is another cross-sectional view of the rotary cutting tool taken along line XI-XI in FIG. 9; and

Fig. 12 is a sectional view of a plate-shaped blade.

Detailed ways

Each of the other features and teachings described above and described below can be used alone or in combination with the other features and teachings to provide improved rotary cutting tools. Exemplary embodiments of the invention showing the use of several of these other features and teachings alone and in combination with each other will now be described in detail with reference to the accompanying drawings. This detailed description is only to teach those skilled in the art in further detail how to practice the preferred aspects of the present invention, but not to limit the scope of the present invention. The scope of the invention is limited only by the claims. Therefore, combinations of features and steps disclosed in the following detailed description are not necessary to practice the invention in the broadest sense, but are instead taught merely to particularly illustrate exemplary embodiments of the invention. Furthermore, individual features of the exemplary embodiments as well as the dependent claims may be combined in ways not specifically listed in order to provide other useful embodiments of the invention.

The best mode for carrying out the present invention will be described below with reference to FIGS. 1 to 11. FIG.

The rotary cutting tool 10 will now be described with reference to FIG. 1 . FIG. 1 shows an exploded perspective view of a rotary cutting tool 10 . The rotary cutting tool 10 is called a "planer head" and has a tool body 14, a centrifugal wedge 16, a blade assembly 18, a fixed plate 24, a protective plate 26, and the like. The tool main body 14 corresponds to a cylindrical main body formed substantially in a cylindrical shape, and has a shaft hole 14 a that accommodates a rotating shaft directly or indirectly driven by a motor. In addition, slots 12 are formed in the outer periphery of the tool body 14 , each slot 12 receiving one of the wedges 16 and one of the blade assemblies 18 .

Each groove 12 has relatively non-parallel side walls 14b and 14c such that the width between the side walls narrows toward the opening of the groove 12 in the outer periphery of the tool body 14 (refer to FIGS. 2 and 10(B)) . Grooves 12 (four grooves in this embodiment) are formed on the outer periphery of the tool body 14 along the axial direction of the tool body 14 . Figure 1 shows three slots 12 that receive a wedge 16 and a blade assembly 18, respectively, and one slot 12 that will receive a wedge 16 and a blade assembly 18 as described below. An exemplary construction and assembly process for wedge 16 and blade assembly 18 will now be described. After the wedge 16 has been received in the corresponding slot 12, the fixing plate 24 and the protective plate 26 are mounted on the tool body 14 by means of the screws S2.

An exemplary construction and assembly process for one of the wedges 16 will now be described with reference to FIGS. 2 and 3 . FIG. 2 shows an exploded perspective view before receiving the wedge 16 , while FIG. 3 shows a perspective view after receiving the wedge 16 . Each wedge 16 is formed to have a generally trapezoidal cross-section and has slits 16a at opposite ends. When wedge 16 is received in slot 12 of body 14 , wedge 16 is retained by two retaining members 28 . That is, the pin 28b mounted on the holding member 28 engages with the slit 16a, and the screw S4 engages with the corresponding screw hole 14d formed in the tool body 14 via the hole 28a formed in the holding member 28 . Each screw hole 14d is located in a recess 14e formed to conform to the shape of the holding member 28 . Figure 3 shows a wedge 16 received in the slot 12 and retained by the pin 28b. The pin 28b can move within the range of the slit 16a (corresponding to the “predetermined range”), whereby the wedge 16 can also move due to the centrifugal force generated by the rotation of the rotary cutting tool 10 . On the other hand, the engagement between pin 28b and slot 16a prevents wedge 16 from falling out or moving unintentionally. In this embodiment, the two pairs of slots 16a and pins 28b are referred to as "retaining members".

Next, an exemplary construction and assembly process of one of the blade assemblies 18 will be described with reference to FIGS. 4 to 7 . FIG. 5(A) shows a perspective view of the assembled blade assembly 18, and FIG. 5(B) shows a cross-sectional view taken along line VB-VB in FIG. 5(A). FIG. 6 shows the process of inserting the blade assembly 18 into the slot 12 . FIG. 7 illustrates a perspective view of the inserted blade assembly 18 .

As shown in FIG. 4 , each blade unit 18 is mainly composed of a blade holding plate 20 and a plate-shaped blade 22 . In FIG. 5(A), the blade holding plate 20 and the plate-shaped blade 22 are assembled to each other by bolts B2 and nuts N2.

The blade holding plate 20 is a member for holding a plate-shaped blade 22, and is composed of a holding plate main body 20b and a bottom portion 20e having a substantially L-shaped cross section. The holding plate main body 20b has a chip discharge portion 20a, a convex portion 20c, and a long hole 20d. The discharge portion 20a has an arcuate cross-section, which helps to discharge chips generated during the cutting operation. For example, in the process of utilizing the pre-adjusting device to adjust the position of the front edge, the connecting parts (i.e., the bolt B2 and the nut N2) are loosened or removed, and then the plate-shaped blade 22 is moved along a predetermined direction (i.e., Fig. 5(B) In the up and down direction D2) move. During this process, the convex portion 20 c functions as a stopper to limit the movement of the plate-shaped blade 22 . Bolt B 2 (for engagement with nut N2) passes through slotted hole 20d.

Referring again to FIG. 4, the plate-like insert 22 includes a cutting portion 22a and an insert main body 22b. The cutting portion 22a is a member for cutting an object such as wood, and is made of a material harder than that of the blade main body 22b (for example, cemented carbide, high-speed tool steel, sintered diamond). The cutting portion 22a is fixed to the blade main body 22b by a predetermined fixing method such as brazing or bonding.

The blade body 22b has a concave portion 22c. A concave portion 22c is formed along the longitudinal direction of the blade main body 22b and between opposite end portions, and engages with the convex portion 20c of the holding plate main body 20b in a manner that allows a certain degree of movement. The concave portion 20c and the convex portion 22c are collectively referred to as an "engagement member".

Regarding the assembly process of the tool body 14, after the wedge 16 is inserted into the groove 12, the blade assembly 18 is inserted into the groove 12, and the fixing plate 24 and the protection plate 26 are fixed with the screws S2. As shown in FIG. 1, the fixing plate 24 has a cutout portion 24a, and the protection plate 26 also has a cutout portion 26a. The cutout portion 24 a and the cutout portion 26 a are formed so that the blade assembly 18 can be attached and detached relative to the corresponding groove 12 after the fixing plate 24 is attached to the tool body 14 . On the other hand, the opposite sides of the wedge 16 and the retaining member 28 are covered by the fixing plate 24 to prevent the wedge 16 from disengaging from the groove 12 . FIG. 6 shows one of the blade assemblies 18 during insertion of the blade assembly 18 into the corresponding slot 12 by moving in direction D4. FIG. 7 shows one of the blade assemblies 18 received in the slot 12 .

The rotary cutting tool 10 shown in FIG. 8 is mounted on a rotation shaft of a motor (not shown) and rotated to cut a workpiece with a cutting portion 22a.

As shown in FIGS. 7 , 8 and 10(A), with respect to each pair of wedge 16 and blade assembly 18 inserted into the groove 12, the flat surface 16b of the wedge 16 and the flat surface 20f of the blade holding plate 20 contact each other. Each blade assembly 18 is fixed as described below, and the corresponding wedge 16 is movable within a predetermined range. Thus, the wedge 16 is moved in direction D6 by the centrifugal force generated by the rotation of the rotary cutting tool 10 so that the wedge 16 and blade assembly 18 are secured between the side walls 14b and 14c at the narrow opening of the slot 12 . The blade assembly 18 is pressed by the wedge 16 in addition to the engagement of the bottom 20e with the engagement groove 12a as described below. Thus, the blade assembly 18 is securely fixed. Therefore, no vibration is generated when an object is cut by the cutting portion 22a.

As shown in FIG. 10(B), each side wall 14c of the groove 12 has an engagement groove 12a. Similar to the groove 12 , the engaging groove 12 a is formed along the axis of the rotary cutting tool 10 and is formed in a concave shape corresponding to the end of the bottom 20 e of the blade holding plate 20 .

Also, as shown in FIG. 11, at least one pressing pin 14f is installed in the bottom of each groove 12 opposite to the bottom 20e (two pressing pins are provided in this embodiment). Each pressing pin 14f is urged by the corresponding elastic member 14g to press the blade assembly 18 toward the outer periphery of the tool body 14 . Therefore, in a state where the end portion of the bottom portion 20e is engaged with the engagement groove 12a, the pressing pin 14f urges the blade assembly 18 to prevent vibration.

Regarding the blade assembly 18, each plate-like blade 22 can be attached to or detached from the corresponding blade holding plate 20 due to engagement/disengagement between the bolt B2 and the nut N2 (refer to FIG. 4 ). Furthermore, the plate-shaped blade 22 is movable within a range defined by the elongated hole 20d (see FIG. 4 ). If the position of the front edge of the plate insert 22 is changed by sharpening the cutting edge of the plate insert 22 (especially the cutting portion 22a), the front edge of the cutting insert can be kept at the original position by moving the plate insert 22. Thus, a single plate-shaped insert 22 can be used for a longer period of time than conventional cutting tool inserts since the cutting edge can be sharpened multiple times. Furthermore, by maintaining a certain distance between the upper surface of the bottom 20e and the cutting edge of the insert, the cutting radius is maintained at a predetermined distance to maintain cutting accuracy.

As shown in FIG. 2 , a pair of retaining members (ie, slot 16 a and pin 28 b ) is provided such that wedge 16 is retained at a predetermined position within slot 12 . In the process of replacing the plate-shaped blade 22 (especially the cutting portion 22a) for purposes such as sharpening, the wedge 16 is held by the corresponding holding member even after the blade assembly 18 is detached, so that the wedge 16 is held when the blade assembly 18 is removed. When inserted into the slot 12, the retaining wedge 16 is not required. Thus, the blade assembly 18 can be installed more quickly since the device according to the present invention requires less attention than conventional devices.

Each engagement member constituted by a convex portion 20c and a concave portion 22c is configured to engage the plate-shaped blade 22 with the blade holding plate 20 to allow movement (refer to FIG. 4 and FIG. 5(B)). Therefore, even if the plate-shaped blade 22 has been detached from the plate-shaped blade 18, the plate-shaped blade 22 can be prevented from coming off due to the centrifugal force.

The best mode for carrying out the present invention has been described above, however, the present invention is not limited to the above-described embodiments. Various modifications can be made within the spirit and scope of the invention. For example, the following changes may be employed.

According to the above-described embodiment, each plate-like insert 22 includes the cutting portion 22a and the insert main body 22b (refer to FIG. 4 ). If the cutting portion 22a and the insert body 22b are made of the same material such as cemented carbide or high speed tool steel, as shown in FIG. 12, a pair of cutting portion 22a and insert body 22b may be formed as a single member. This prevents the cutting portion 22a from being detached from the blade body 22b.

According to the above-described embodiment, each engagement member is constituted by the convex portion 20c formed on the blade holding plate 20 and the concave portion 22c formed on the plate-shaped blade 22 (refer to FIGS. 4 and 5 ). Instead of this embodiment, as an engaging member, a recess (a long hole or a long groove) may be formed on one of the blade holding plate 20 and the plate-shaped blade 22, and a protrusion engaging the recess may be formed on the other. In addition, protrusions (or recesses) may be formed on constituent parts of the rotary cutting tool (such as the fixed plate 24 or the protection plate 26, etc.), and recesses (or protrusions) engaging with the protrusions (or recesses) may be formed on the blade Hold the plate 20 or the plate-like blade 22 on. In either embodiment, the engagement features prevent the plate blades 22 from being discarded even if each plate blade 22 has been removed from the corresponding blade assembly 18 . The same result can also be achieved by using a hole or a cutout portion instead of the recess. In addition, an engaging part is provided to sufficiently fix the blade assembly by the connecting part. If no engaging member is provided, the plate-shaped blade 22 may not have the recess 22c and may be configured as a flat blade.

According to the above-described embodiment, each holding member is constituted by the slit 16a formed on the wedge 16 and the pin 28b formed on the holding member 28 (refer to FIG. 2 ). Instead of this embodiment, a protrusion similar to the pin 28b may be formed on the wedge 16 and a groove (or long hole) similar to the slit 16a may be formed on the holding member 28 as a holding member. Furthermore, the wedge 16 may be held by a protective plate 26 instead of a corresponding holding member 28 . That is, a pin may be formed on a portion of the protection plate 26 opposite to the slit 16a of the wedge 16, or a groove (or a long hole) may be formed on a portion of the protection plate 26 opposite to the convex portion of the wedge. In either embodiment, because the wedge 16 is held by the retaining features, the blade assembly 18 can be assembled more easily and quickly than conventional arrangements.

According to the above-described embodiment, each fixing member is constituted by the bolt B2 and the nut N2 (refer to FIG. 4 ). Alternatively, screws or rivets or the like may be used. Even if other fixing members are used, the blade holding plate 20 can be firmly connected with the plate-like blade 22, so that, of course, the position of the front blade can be adjusted.

This application claims priority from Japanese Patent Application Serial No. 2007-201822, the contents of which are hereby incorporated by reference.

Claims (2)

1. A rotary cutting tool comprising: At least one groove formed in the outer periphery of the cylindrical body of the rotary cutting tool in the axial direction of the cylindrical body and having opposite side walls inclined relative to each other such that the side walls the width between decreases towards the opening of the slot; at least one blade assembly comprising a plate-shaped blade and a blade holding plate and configured such that the plate-shaped blade is detachable from the blade holding plate and movable in a direction to adjust a cutting radius of the blade; and at least one wedge having a predetermined cross-section; wherein said blade assembly and said wedge may be received in corresponding said slots such that the cutting portion of said plate-shaped blade protrudes from said opening; and When the cylindrical body is rotated, the blade assembly is held in the groove by the wedge under the action of centrifugal force, The rotary cutting tool also includes at least one retaining member configured to retain a corresponding wedge within a predetermined range within the groove. 2. The rotary cutting tool of claim 1, further comprising at least one engagement member, each engagement member configured to engage the plate-like blade with the blade retaining plate and At least one of the constituent parts of the rotary cutting tool engages to allow movement of the plate-like blade in the direction.

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