CN101992305B - Balance adjustable cutting tool - Google Patents

Abstract

The invention discloses a cutting tool with adjustable balance, which comprises a tool body, a tool holder, a cutting blade and a tool holder fastener. The knife holder is placed in the knife groove together with the knife holder. The knife body is provided with a countersunk hole communicating with the knife groove, and the knife holder is provided with fastening threaded holes corresponding to the countersunk hole. The tool holder fastener is installed in the counterbore and is threadedly connected with the fastening threaded hole, and the tool holder is compressed and fixed by the tool holder fastener. The balance-adjustable cutting tool has the advantages of simple and compact structure, convenient processing and production, and low production cost.

Description

A cutting tool with adjustable balance

technical field

The invention relates to the field of metal cutting, in particular to a cutting tool with adjustable balance.

Background technique

It has been found that during the cutting process of rotary cutting tools, high-speed cutting (especially when the linear speed V≥5000m/min) can greatly improve the processing efficiency and improve the quality of the processed surface. In the process of high-speed cutting, the eccentric mass produces a large unbalanced centrifugal force, which makes the cutting tool easy to vibrate and reduces the quality of the machined surface. This type of existing cutter generally adopts the structure shown in Figure 1 and Figure 2. In order to reduce the unbalanced centrifugal force, it is necessary to reduce the eccentric mass of the cutting tool relative to the center of rotation, so the cutter body 1 adopts a material with low density (usually aluminum alloy), compared with ordinary cutting tool materials (generally steel), this type of material has the characteristics of low density, low strength, low hardness, and no wear resistance. The service life of the tool is improved without reducing the clamping force of the fastener on the cutting blade 3. Generally, the fastener does not directly act on the cutter body 1, but directly connects the cutting blade 3 to the tool holder 2 with better strength. After putting it on, pass through a column hole 36 on the cutter body 1 with the tool clip fastener 5 to connect a steel sleeve 37. There are several tapered holes 38 on the outer surface of the steel sleeve 37, and the screws 40 orthogonal to the axis 39 of the steel sleeve pass through. Cooperate with the threaded hole on the cutter body 1 and press it into the taper hole 38, so that the steel sleeve 37 is fixedly connected with the cutter body 1, and the tool holder fastener 5 acts on the internal thread surface of the steel sleeve 37 to clamp the tool holder 2 and the cutting blade 3 Tightly on the knife body 1. The tool holder fastener 5 is indirectly connected to the cutter body 1 through the steel sleeve 37, which increases the clamping force of the cutter holder fastener 5, and can effectively prevent the tool holder fastener 5 from being directly connected to the cutter body 1 due to the friction on the cutter body 1. The thread surface is not wear-resistant and reduces the life of the cutting tool. Although the use of such a low-density material to make the cutter body 1 can effectively reduce the eccentric mass of the cutting tool, it cannot be completely eliminated. In order to ensure the quality of the machined surface, such tools generally have a dynamic balance adjustment structure. In order to achieve dynamic balance cutting, usually on the outer peripheral surface near the non-cutting end of the cutting tool, there are balancing parts with the same number as the cutting blade 3 6. The balancing pieces 6 are evenly distributed on a circle perpendicular to the central axis of the cutting tool, and the eccentric quality of the cutting tool can be adjusted by moving the balancing piece 6 in the radial direction of the circle. This structure with adjustable dynamic balance can effectively avoid the influence of unbalanced centrifugal force on cutting.

However, a steel sleeve 37 is embedded in the cutter body 1, which makes the structure of the cutting tool too complicated, and requires high assembly accuracy of the cutter body 1, which greatly increases the cost of making and using the cutting tool; at the same time, during high-speed cutting, With the increase of cutting speed, the centrifugal force suffered by the balance member 6 gradually increases. Due to the insufficient strength of the cutter body 1, the centripetal force that can be provided is limited, and the balance member 6 is easy to fly out.

Contents of the invention

The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art, and provide a balance-adjustable cutting tool with simple and compact structure, easy processing and low production cost.

In order to solve the problems of the technologies described above, the present invention adopts the following technical solutions:

A cutting tool with adjustable balance includes a cutter body, a cutter holder, a cutting blade and a fastener for the cutter holder. It is placed in the knife groove together with the knife holder. The knife body is provided with a countersunk hole communicating with the knife groove. The knife holder is provided with a fastening threaded hole corresponding to the countersunk hole. The knife holder The fastener is arranged in the counterbore and is threadedly connected with the fastening threaded hole, and the tool holder is pressed and fixed by the fastener of the tool holder.

The tool holder is provided with a connecting threaded hole, and the cutting blade is fixed on the tool holder through a connecting fastener connected with the connecting threaded hole. The included angle in the axial direction is α, the included angle between the fastening threaded hole and the connecting threaded hole in the axial direction of the cutter body is β, 0°≤α≤45°, 0°≤β≤25°.

The sipe is surrounded by a bottom surface of the groove, a positioning surface and a smooth surface, and a shallow hole arranged coaxially with the connecting threaded hole is arranged on the bottom surface of the groove, and the included angle between the positioning surface and the central axis of the shallow hole is γ , the tool holder is provided with a boss, and the outer side of the tool holder is provided with a lower bottom surface in contact with the bottom surface of the groove and a contact surface in contact with the smooth surface, and the outer side of the tool holder is provided with a bottom surface in contact with the smooth surface. The outer peripheral surface in contact with the positioning surface, the included angle between the outer peripheral surface and the central axis of the connecting threaded hole is λ, 0.25°≤λ-γ≤3°.

An inclined surface is provided between the positioning surface of the knife groove and the bottom surface of the groove, a clearance surface is provided between the outer peripheral surface and the lower bottom surface of the knife holder, and a pre-tightening gap is provided between the inclined surface and the clearance surface.

The inclined plane is parallel to the clearance plane.

The smooth surface is orthogonal to the bottom surface of the groove, and the contact surface is orthogonal to the lower bottom surface.

The boss of the tool holder is provided with a balance threaded hole, the cutter body is provided with a cutter body threaded hole corresponding to the balance threaded hole, and the balance piece is threaded through the cutter body threaded hole and the balance threaded hole.

The central axis of the threaded hole of the cutter body is coplanar with the central axis of rotation of the cutter body.

One end of the threaded hole of the cutter body is connected to the balanced threaded hole, and the other end is communicated with the installation hole in the center of the cutter body, and the cutting blade is blocked by the balanced threaded hole of the tool holder.

Compared with the prior art, the present invention has the advantages of:

The balance-adjustable cutting tool of the present invention not only cancels the complex structure of the existing steel sleeve connection mode, but also eliminates the complex structure of the existing steel sleeve connection method by providing a countersunk hole on the cutter body and directly connecting the tool holder fasteners inserted into the countersunk hole with the tool holder. The structure is greatly simplified, the production cost is reduced, and the tool holder and the cutting blade can be more firmly clamped on the tool body, thereby improving the cutting accuracy of the cutting tool in high-speed cutting. By reasonably setting the angle between the fastening threaded hole and the connecting threaded hole on the tool holder along the radial direction and axial direction of the tool body, it can effectively prevent the fasteners of the tool holder from flying out under the influence of centrifugal force when the tool body rotates at high speed , At the same time, the tool holder can generate normal, radial and axial pressure on the tool groove, effectively reducing the contact gap between the tool body and the tool holder. By setting a certain included angle between the positioning surface of the tool holder and the outer peripheral surface of the boss on the tool holder, the boss can be elastically deformed when the tool holder is fixed, so that the connection between the tool holder and the tool holder is more compact and stable. There is a clearance surface between the lower bottom surface and the outer peripheral surface of the tool holder. The clearance surface can reduce the elastic wall thickness of the boss while reducing the quality of the tool holder, so that the boss is more likely to be elastically deformed. There is a pre-tightening gap between the clearance surface and an inclined surface of the cutter body. The elastic deformation of the boss can make the cutter body and the tool holder completely contact in the radial direction of the cutter body, eliminating the pre-tightening gap and improving the connection. Stability also improves the stability of the cutting tool during radial feed. The balance part passes through the threaded hole of the cutter body and is threadedly connected with the balance threaded hole set on the boss of the tool holder. The balance part can not only adjust the cutting dynamic balance, but also connect the cutter body and the tool holder together to make the tool The clip and the cutter body form an over-positioning structure, so that the cutting tool has strong impact resistance. In the process of high-speed cutting, when the cutting speed reaches the cutter body threaded hole is not enough to overcome the centrifugal force of the balance piece, the balance threaded hole on the tool holder with better strength can help the balance piece overcome the centrifugal force, in order to increase the upper limit of cutting speed. Favorable conditions. The cutting blade blocks the balance threaded hole of the tool holder. When the threaded hole of the cutter body and the balance threaded hole on the tool holder are not enough to overcome the centrifugal force of the balance piece, the cutting blade prevents the balance piece from flying out. Protect the safety of operators.

Description of drawings

Fig. 1 is a schematic diagram of the first three-dimensional structure of a cutting tool in the prior art;

Fig. 2 is the second three-dimensional structure schematic diagram of cutting tool in the prior art;

Fig. 3 is the three-dimensional structure schematic diagram of cutting tool of the present invention;

Fig. 4 is the enlarged schematic view of the sipe in the cutting tool of the present invention;

Fig. 5 is a schematic diagram of the front view of the sipe in the cutting tool of the present invention;

Fig. 6 is the three-dimensional structure schematic diagram of toolholder in cutting tool of the present invention;

Fig. 7 is a front structural schematic view of the tool holder in the cutting tool of the present invention;

Fig. 8 is a schematic diagram of the three-dimensional structure of the cutting blade in the cutting tool of the present invention;

Fig. 9 is a sectional view of AA of Fig. 5;

Fig. 10 is a sectional view of BB of Fig. 7;

FIG. 11 is a CC sectional view of FIG. 7 .

Each label in the figure means:

1. Tool body; 2. Toolholder; 3. Cutting blade; 4. Connecting fastener; 5. Toolholder fastener; 6. Balance piece; 7. Chip groove; 8. Tool groove; 9. Smooth surface ;10, positioning surface; 11, threaded hole of cutter body; 12, shallow hole; 13, countersunk hole; 14, groove bottom surface; 15, inclined surface; 16, contact surface; 17, outer peripheral surface; Balance threaded hole; 20, connecting threaded hole; 21, lower bottom surface; 22, fastening threaded hole; 23, inner peripheral surface; 24, radial surface; 25, clearance surface; 26, pre-tightening clearance; 27, upper bottom surface ; 28, boss; 30, end face; 31, side; 32, base surface; 36, column hole;

Detailed ways

Fig. 3 to Fig. 11 have shown a kind of cutting tool embodiment with adjustable balance of the present invention, and this cutting tool comprises cutter body 1, cutter holder 2, cutting blade 3 and cutter holder fastener 5, and cutter body 1 is provided with At least one set of sipe 8 and balancer 6, tool holder 2 has three inner positioning surfaces composed of radial surface 24, inner peripheral surface 23 and upper bottom surface 27, end surface 30 of cutting blade 3 cooperates with radial surface 24, cutting The side surface 31 of the blade 3 is matched with the inner peripheral surface 23, the base surface 32 of the cutting blade 3 is matched with the upper bottom surface 27, the tool holder 2 is provided with a connecting threaded hole 20, and the cutting blade 3 is fastened by connecting with the connecting threaded hole 20. The part 4 is fixed on the tool holder 2, and a group of cutting blades 3 and the tool holder 2 are installed in each sipe 8. In this embodiment, only one group of sipes 8 and balance parts 6 and a group of corresponding cutting blades 3 and 6 are provided. Tool holder 2, chip flute 7 is arranged beside the knife groove 8, and the quantity of the knife groove 8, balancer 6, cutting blade 3 and tool holder 2 can be determined according to the needs of specific cutting conditions. The slot 8 communicates with the countersunk hole 13, the tool holder 2 is provided with a fastening threaded hole 22 corresponding to the countersunk hole 13, and the tool holder fastener 5 is installed in the countersunk hole 13 and threaded with the fastening threaded hole 22 , the tool holder 2 is compressed and fixed by the tool holder fastener 5 . The balance-adjustable cutting tool of the present invention provides a countersunk hole 13 on the cutter body 1, and directly connects the tool holder fastener 5 and the tool holder 2 loaded into the countersunk hole 13, which not only cancels the existing steel sleeve connection The complex structure of the method greatly simplifies the structure, reduces the production cost, and can clamp the tool holder 2 and the cutting blade 3 on the tool body 1 more stably, thereby improving the cutting accuracy of the cutting tool in high-speed cutting.

In this embodiment, the included angle between the fastening threaded hole 22 and the connecting threaded hole 20 along the radial direction of the cutter body 1 is α, and the included angle between the fastening threaded hole 22 and the connecting threaded hole 20 along the axial direction of the cutter body 1 is β, 0°≤α≤45°, 0°≤β≤25°, in this embodiment, α is 10°, and β is 15°. By reasonably setting the included angle between the fastening threaded hole 22 on the tool holder 2 and the connecting threaded hole 20 along the radial direction and the axial direction of the tool body 1, it can effectively prevent the tool holder fastener 5 from rotating at high speed with the tool body 1 At the same time, it is affected by the centrifugal force and flies out. At the same time, the tool holder 2 can generate normal, radial and axial pressure on the tool groove 8, effectively reducing the contact gap between the tool body 1 and the tool holder 2.

In this embodiment, the sipe 8 is surrounded by the groove bottom surface 14, the positioning surface 10 and the smooth surface 9, the smooth surface 9 is orthogonal to the groove bottom surface 14, and the groove bottom surface 14 is provided with a shallow groove coaxially arranged with the connecting threaded hole 20. The hole 12, the included angle between the positioning surface 10 and the central axis of the shallow hole 12 is γ, the tool holder 2 is provided with a boss 28, and the outer side of the tool holder 2 is provided with a lower bottom surface 21 and a contact surface 16, and the contact surface 16 is positive to the lower bottom surface 21. Cross, the outside of the boss 28 of the tool holder 2 is provided with an outer peripheral surface 17, the angle between the outer peripheral surface 17 and the central axis of the connecting threaded hole 20 is λ, 0.25°≤λ-γ≤3°, in this embodiment, λ-γ is 0.75°, the difference makes a certain angle between the positioning surface 10 of the tool groove 8 and the outer peripheral surface 17 of the boss 28 on the tool holder 2, and the boss 28 is formed when the tool holder 2 is fixed by the tool holder fastener 5 The elastic deformation makes the lower bottom surface 21 in close contact with the groove bottom surface 14, the contact surface 16 in close contact with the smooth surface 9, and the outer peripheral surface 17 in close contact with the positioning surface 10, so as to ensure that the connection between the knife holder 2 and the knife groove 8 is tighter and more stable. An inclined surface 15 is provided between the positioning surface 10 of the knife groove 8 and the groove bottom surface 14, and a clearance surface 25 is provided between the outer peripheral surface 17 of the knife holder 2 and the lower bottom surface 21, and the clearance surface 25 reduces the quality of the knife holder 2. At the same time, the elastic wall thickness of the boss 28 can be reduced, so that the boss 28 is more likely to be elastically deformed, and a pre-tightening gap 26 is provided between the inclined surface 15 and the clearance surface 25, and the inclined surface 15 is parallel to the clearance surface 25. The elastic deformation of the platform 28 can make the cutter body 1 and the tool holder 2 fully contact in the radial direction of the cutter body 1, and while eliminating the pre-tightening gap 26 and improving the connection stability, it also improves the radial feeding of the cutting tool. stability.

In this embodiment, the boss 28 of the tool holder 2 is provided with a balance threaded hole 19, the cutter body 1 is provided with a cutter body threaded hole 11 corresponding to the balance threaded hole 19, and the balance member 6 passes through the cutter body threaded hole 11 and The balance threaded hole 19 is threaded, the central axis of the cutter body threaded hole 11 is coplanar with the rotation center axis of the cutter body 1, one end of the cutter body threaded hole 11 is connected with the balance threaded hole 19, and the other end is connected with the mounting hole in the center of the cutter body 1 18 connected, the balance piece 6 moves axially along the threaded hole 11 of the cutter body and the balance threaded hole 19 to adjust the cutting dynamic balance. It forms an over-positioning structure with the cutter body 1, so that the cutting tool has strong impact resistance. In the high-speed cutting process, when the cutting speed reaches the cutter body threaded hole 11 of the cutter body 1, it is not enough to overcome the centrifugal force of the balance piece 6, the balance threaded hole 19 on the tool holder 2 with better strength can help the balance piece 6 overcome the centrifugal force, for Increasing the upper limit of cutting speed improves the favorable conditions. The cutting blade 3 is blocked at the balance threaded hole 19 of the tool holder 2. When both the cutter body threaded hole 11 of the cutter body 1 and the balance threaded hole 19 on the tool holder 2 are not enough to overcome the centrifugal force of the balance member 6, the cutting blade 3 The blade 3 prevents the balance member 6 from flying out, which can protect the safety of the operator. According to the process requirements, the balance threaded hole 19 in the balance-adjustable cutting tool of the present invention can be replaced by a through hole with a diameter slightly larger than the outer diameter of the balance piece 6, and the balance piece 6 can move in the through hole, but is not limited by it , the cutter body threaded hole 11 overcomes the centrifugal force suffered by the balancer 6 during high-speed cutting. When the cutter body threaded hole 11 is insufficient to overcome the centrifugal force, the cutting blade 3 directly blocks the balancer 6 from flying out; in addition, the cutting blade 3 Not only can it be fixed on the tool holder 2 by connecting fasteners 4 as described in this embodiment, but also the cutting blade 3 and the tool holder 2 can be permanently connected by methods such as welding.

The above are only preferred embodiments of the present invention, and do not limit the present invention in any form. Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Any person familiar with the art, without departing from the scope of the technical solution of the present invention, can use the technical content disclosed above to make many possible changes and modifications to the technical solution of the present invention, or modify it into an equivalent implementation of equivalent changes example. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention shall fall within the protection scope of the technical solution of the present invention.

Claims (6)

1. cutting tool that balance is adjustable; Comprise cutter hub (1), cutter holder (2), cutting tip (3) and cutter holder securing member (5); Said cutter hub (1) is provided with at least one group of cutter groove (8) and balance element (6); Said cutting tip (3) is fixed in cutter holder (2) and goes up and together place in the cutter groove (8) with cutter holder (2); It is characterized in that: said cutter hub (1) is provided with the counter sink (13) that communicates with cutter groove (8); Said cutter holder (2) is provided with the fastening screw pit (22) corresponding with said counter sink (13), and said cutter holder securing member (5) is installed in the counter sink (13) and with said fastening screw pit (22) and is threaded, and said cutter holder (2) is fixed through cutter holder securing member (5); Said cutter holder (2) is provided with connection screw thread hole (20); Said cutting tip (3) is fixed on the cutter holder (2) through the connection securing member (4) that is connected with said connection screw thread hole (20), and said fastening screw pit (22) is α with said connection screw thread hole (20) along cutter hub (1) angle in the radial direction, and said fastening screw pit (22) is β with said connection screw thread hole (20) along the angle on cutter hub (1) axial direction; 0 °≤α≤45 °; 0 °≤β≤25 °, said cutter groove (8) is surrounded by groove bottom (14), locating surface (10) and fairing face (9), and said groove bottom (14) is provided with the shallow bore hole (12) with said connection screw thread hole (20) coaxial arrangement; Said locating surface (10) is γ with the angle of shallow bore hole (12) central axis; Said cutter holder (2) is provided with boss (28), and said cutter holder (2) outside is provided with bottom surface (21) that contacts with said groove bottom (14) and the contact-making surface (16) that contacts with said fairing face (9), and boss (28) outside of said cutter holder (2) is provided with the outer peripheral face (17) that contacts with said locating surface (10); Said outer peripheral face (17) is λ with the angle of said connection screw thread hole (20) central axis, 0.25 °≤λ-γ≤3 °.

2. the adjustable cutting tool of balance according to claim 1; It is characterized in that: be provided with an inclined-plane (15) between the locating surface (10) of said cutter groove (8) and the groove bottom (14); Be provided with clearance face (25) between the outer peripheral face (17) of said cutter holder (2) and the bottom surface (21), be provided with pretension gap (26) between said inclined-plane (15) and the said clearance face (25).

3. the adjustable cutting tool of balance according to claim 2 is characterized in that: said inclined-plane (15) are parallel with said clearance face (25).

4. the adjustable cutting tool of balance according to claim 3 is characterized in that: said fairing face (9) and said groove bottom (14) quadrature, said contact-making surface (16) and said bottom surface (21) quadrature.

5. according to the adjustable cutting tool of each described balance in the claim 1 to 4; It is characterized in that: the boss (28) of said cutter holder (2) is provided with balance screwed hole (19); Said cutter hub (1) is provided with the cutter hub screwed hole (11) corresponding with balance screwed hole (19), and said balance element (6) passes cutter hub screwed hole (11) and is threaded with balance screwed hole (19).

6. the adjustable cutting tool of balance according to claim 5 is characterized in that: the centre of gyration axis coplane of the central axis of said cutter hub screwed hole (11) and said cutter hub (1).

Images