Rotary cutter

Abstract

The utility model relates to a rotary cutter, which comprises a cutter main body, the cutter main body is provided with a main body central axis B for limiting a relative forward direction DF and a backward direction DR, and the cutter main body can rotate around the main body central axis B in a rotating direction R; the front end side of the screw is screwed into the corresponding middle position of the cutter body, so that the cutter body is clamped relative to the adapter / cutter handle, and the cutter body is provided with a cavity into which the screw is screwed; the main cooling channel is formed in the center of the screw and is directly communicated with the cooling channel on the adapter / cutter handle; the coolant collecting chamber is positioned at the downstream of the main cooling channel; and the sub-cooling channels are formed in the cutter main body and are communicated with the coolant collecting chamber through a primary cooling channel. Cooling liquid can directly cool the cutting edge, temperature rise caused after the cutter body is pre-cooled is avoided, and the rigidity of the cutter is guaranteed through an annular cavity formed by gaps in the cutter body.

Description

Technical Field

[0001] The utility model relates to a cutting tool, in particular to a light cutting tool such as a milling cutter. Background Art

[0002] The diameter of the cooling channel inside the rotary tool is usually large, and the outflow port of the cooling channel is usually aligned with the top of the cutting edge, and cannot be aligned with all the key cutting areas of the cutting edge, resulting in poor cooling effect of the cutting edge and a large amount of coolant waste. For example, a Chinese utility model patent with application number CN202110029855.7, "Indexable Milling Cutter with Precise Coolant Flow" (publication number CN113231680A), discloses a rotary tool, the adapter of which is fastened to the tool body by a clamping screw, and the inside of the adapter is provided with a main coolant channel and a secondary coolant channel extending from the main coolant channel to the front end surface of the adapter, and the coolant manifold is connected to the main coolant channel, and the coolant fluid after passing through the coolant manifold is collected in the coolant reservoir and supplied to multiple specific key areas of the cutting edge through various coolant ducts.

[0003] This type of tool can effectively cool each key part of the cutting edge, avoiding the waste of coolant, but at the same time it brings the following problems: First, the fluid in the main coolant can enter the coolant reservoir after passing through the secondary coolant channel and the coolant manifold, and the secondary coolant channel and the coolant manifold inside the adapter are easy to reduce its rigidity and firmness, and cannot reliably avoid fracture. Its hardening treatment is difficult and stress cracks are prone to occur; second, during the cutting process, the heat generated by the cutting edge and the workpiece will be transferred to the tool body by heat conduction. The coolant of the rotary tool can only cool the blade part after cooling the hot tool body. At this time, the coolant leading to the blade part will heat up after the first round of pre-cooling of the tool body, which will affect the cooling effect of the coolant on the blade part. For this reason, further improvements are needed to the rotary tool. Utility Model Content

[0004] The first technical problem to be solved by the utility model is to provide a rotary cutter with better rigidity in view of the above-mentioned existing technical status.

[0005] The second technical problem to be solved by the present invention is to provide a rotary tool with good cutting edge cooling effect in view of the above-mentioned existing technical status.

[0006] The technical solution adopted by the utility model to solve the above technical problems is: the rotary cutter comprises:

[0007] a tool body having a body central axis B defining a relative forward direction DF and a rearward direction DR, and said tool body being rotatable about said body central axis B in a rotational direction R;

[0008] A screw is screwed into the corresponding center position of the tool body at the front end side, thereby clamping the tool body relative to the adapter / tool ​​handle, and correspondingly, the tool body has a cavity for the screw to be screwed into;

[0009] It is characterized by: it also includes:

[0010] A main cooling channel is provided in the center of the screw and is directly connected to the cooling channel on the adapter / tool ​​holder;

[0011] A coolant collection chamber, located downstream of the main cooling channel, for collecting coolant; and

[0012] A sub-cooling channel is provided on the tool body and guides the coolant to the cutting area, and is connected with the coolant collecting chamber through a primary cooling channel. The cross-sectional area of ​​the coolant collecting chamber is larger than the cross-sectional area of ​​the sub-cooling channel.

[0013] In order to meet the processing requirements of the workpiece, as a preferred embodiment, the tool body is divided into a roughing tool body located at the rear and a finishing tool body located at the front, and the sub-cooling channel is only provided on the finishing tool body. The roughing tool body and the finishing tool body are mutually embedded, the roughing tool body is provided with a rough cutting edge, and the finishing tool body is provided with a finishing cutting edge, which respectively meet the roughing and finishing requirements of the workpiece.

[0014] In order to cool the tool body, preferably, an annular cavity connected to the coolant collection chamber is formed between at least the structure of the screw and the cavity, and the annular cavity is connected to the coolant collection chamber through a secondary cooling channel, and the secondary cooling channel is located upstream of the first cooling channel, and the rough tool body is directly cooled through the annular cavity. The coolant in the main cooling channel enters the coolant collection chamber for collection, and then a part of the coolant enters the annular cavity formed between the rough tool body and the screw through the secondary cooling channel. The coolant in the annular cavity can cool the side wall of the rough tool body, and the other part of the coolant flows directly through the first cooling channel to the end of the annular cavity.

[0015] In order to form a closed coolant flow channel, preferably, the screw includes a main body for setting the main cooling channel and the secondary cooling channel, and an extension located at the front end of the main body and extending radially outward, and the extension abuts against the front end side of the tool body to close the front end of the annular cavity. The coolant first enters the coolant collection chamber from the main cooling channel set in the main body of the screw, and then is divided into two branches in the coolant collection chamber, one part flows out through the first cooling channel, and the other part enters the annular cavity through the second cooling channel. The bottom of the annular cavity is abutted by the extension of the screw so that the coolant does not flow out from the bottom gap. The coolants in the first cooling channel and the second cooling channel are collected and enter the sub-cooling channel together.

[0016] Furthermore, the cross section of the main body is in an inverted "T" shape, including a vertical section for setting the main cooling channel and a transverse section for setting the first cooling channel and the second cooling channel, and the extension is located at the front end of the transverse section. The main cooling channel extends axially from the vertical section of the screw to the transverse section, and the transverse section is provided with a coolant collection chamber, which is connected to the end of the main cooling channel, and a plurality of first cooling channels and second cooling channels are opened on the coolant collection chamber.

[0017] In order to realize how the screw is surrounded to form an annular cavity space, the tool design is considered as follows: the cavity on the tool body is surrounded by an annular inner step, including a first wall surface located above the step and a second wall surface located below the step, a central hole for the vertical section to pass through is opened in the center of the first wall surface, and the rear end of the transverse section abuts against the first wall surface to close the rear end of the annular cavity, and the gap between the lateral wall of the transverse section and the second wall surface constitutes the spatial area of ​​the annular cavity. Among them, the vertical section of the screw extends from the central hole to the outside of the cavity of the tool body, the upper circumference of the transverse section of the screw abuts against the second wall surface of the annular inner step, and the gap between the lateral wall of the transverse section and the second wall surface is an annular cavity space for the coolant of the secondary cooling channel to flow into.

[0018] In order to facilitate processing and flow guidance, preferably, the axis of the first cooling channel and the central axis (B) of the main body have an angle α, and 30°≤α≤60°. The first cooling channel is opened in the transverse section of the screw. Due to the limited space in the transverse section, during the opening process, it is necessary to ensure that the coolant can be smoothly guided and the end of the first cooling channel can be opened to the fine cutter body and connected to the sub-cooling channel in the fine cutter body.

[0019] Compared with the prior art, the advantages of the utility model are:

[0020] 1. The gap between the side wall of the tool body and the screw forms an annular cavity, which connects the coolant collection chamber and the sub-cooling channel, avoiding the opening of the internal flow channel of the tool body, thereby ensuring the rigidity of the tool;

[0021] 2. A part of the coolant in the coolant collection chamber enters the annular cavity through the secondary cooling channel to cool the tool body, and the other part of the coolant cools the cutting edge through the primary cooling channel, thereby avoiding the coolant being pre-cooled by the tool body and causing the temperature to rise, thereby affecting the cooling effect of the cutting edge. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a three-dimensional structural schematic diagram of an embodiment of the utility model;

[0023] Figure 2 It is an exploded schematic diagram of an embodiment of the utility model;

[0024] Figure 3 This is an exploded schematic diagram of the fine cutter body and the screw in the embodiment of the utility model;

[0025] Figure 4 for Figure 3 A magnified schematic diagram of the local structure;

[0026] Figure 5 It is a longitudinal cross-sectional schematic diagram in an embodiment of the utility model;

[0027] Figure 6 It is a longitudinal cross-sectional schematic diagram of an embodiment of the utility model (screws omitted);

[0028] Figure 7 It is a schematic cross-sectional view of an embodiment of the utility model.

[0029] In the figure: 1. tool body; 11. fine tool body; 12. rough tool body; 13. cavity; 131. first wall; 132. second wall; 2. screw; 21. main body; 211. transverse section; 212. vertical section; 22. extension; 3. main cooling channel; 4. sub-cooling channel; 5. first cooling channel; 6. second cooling channel; 7. coolant collection chamber; 8. annular cavity; 9. adapter. DETAILED DESCRIPTION

[0030] The present invention will be described in further detail below in conjunction with the accompanying drawings.

[0031] like Figures 1 to 7 The rotary tool can be any type of rotary cutting tool, such as a boring bar, a drill bit, etc., and the adapter 9 used with the rotary cutting tool can also be any type of adapter 9, such as a non-tapered or cylindrical adapter.

[0032] The rotary tool of this embodiment includes a tool body 1 having a main body center axis B defining a relative forward direction DF and a rearward direction DR, and the tool body 1 can rotate around the main body center axis B in the rotation direction R; it also includes a screw 2 screwed into the corresponding center position of the tool body 1 on the front end side, and an adapter / tool ​​handle clamped to the tool body 1. This embodiment is explained using the adapter 9 as an example. Correspondingly, the tool body 1 has a cavity 13 for screwing the screw 2 into; and a main cooling channel 3 opened in the center of the screw 2 and directly connected to the cooling channel on the adapter 9; it also includes a coolant collection chamber 7 for collecting coolant, the coolant collection chamber 7 is located downstream of the main cooling channel 3; and a sub-cooling channel 4 opened on the tool body 1 and guiding the coolant to the cutting area, the sub-cooling channel 4 is connected to the coolant collection chamber 7 through the primary cooling channel 5, and the cross-sectional area of ​​the coolant collection chamber 7 is larger than the cross-sectional area of ​​the sub-cooling channel 4.

[0033] Different workpieces or different parts of workpieces have different precision requirements during machining. In order to meet the machining requirements, the tool body is divided into a rough tool body located at the rear and a fine tool body located at the front. Figure 1 The rough cutter body and the fine cutter body are interlocked. The rough cutter body is provided with a rough cutting edge, and the fine cutter body is provided with a fine cutting edge, which respectively meet the rough processing and fine processing requirements of the workpiece. The cutting edge and the workpiece will generate a lot of heat during the cutting process. The heat is mainly distributed in the cutting part of the cutting edge and the cutter body. The fine cutter body is provided with a sub-cooling channel, and the coolant is supplied to each cutting edge through the sub-cooling channel; in order to cool the inside of the cutter body, refer to Figure 5 , an annular cavity connected to the coolant collection chamber is formed between at least the structure of the screw and the cavity, and the annular cavity is connected to the coolant collection chamber through a secondary cooling channel, and the secondary cooling channel is located upstream of the primary cooling channel, while the roughing tool body is directly cooled through the annular cavity. The coolant in the main cooling channel enters the coolant collection chamber for collection, and then a part of the coolant enters the annular cavity formed between the roughing tool body and the screw through the secondary cooling channel. The coolant in the annular cavity can cool the side wall of the roughing tool body, and the other part of the coolant flows directly through the primary cooling channel to the end of the annular cavity.

[0034] In addition, the main cooling channel and the secondary cooling channel inside the rotating tool are both opened on the main body of the screw, and the front end of the main body extends radially outward to form an extension portion, which abuts against the front end side of the tool body to close the front end of the annular cavity. Figures 3 to 5The cross section of the main body is an inverted "T" shape, including a vertical section for setting the main cooling channel and a transverse section for setting the first cooling channel and the second cooling channel. The steps of the coolant participating in the cooling are: the coolant first enters the coolant collection chamber from the main cooling channel set in the main body of the screw, and then is divided into two branches in the coolant collection chamber, one part flows out through the first cooling channel, and the other part enters the annular cavity through the second cooling channel. The bottom of the annular cavity is abutted by the extension of the screw so that the coolant does not flow out from the bottom gap. The coolants in the first cooling channel and the second cooling channel are collected and enter the branch cooling channel together. The annular cavity is formed by the tool body and the screw. The cavity on the tool body is surrounded by an annular inner step, including a first wall surface located above the step and a second wall surface located below the step. A central hole for the vertical section to pass through is opened in the center of the first wall surface, and the rear end of the transverse section abuts against the first wall surface to close the rear end of the annular cavity, and the gap between the side circumferential wall of the transverse section and the second wall surface constitutes the space area of ​​the annular cavity. Reference Figure 5 and Figure 6 The vertical section of the screw extends from the central hole to the outside of the cavity of the tool body, the upper surface of the transverse section of the screw abuts against the second wall of the annular inner step, and the gap between the side wall of the transverse section and the second wall is the annular cavity space for the coolant of the secondary cooling channel to flow into. A part of the coolant in the coolant collection chamber is guided to the end of the annular cavity through the primary cooling channel, and this part of the coolant does not participate in the cooling of the tool body. Reference Figure 5 There is an angle α between the axis of the first cooling channel and the central axis B of the main body, and the angle can be set between 30° and 60°. The first cooling channel is affected by many factors during processing. Due to the limited space in the transverse section, it is necessary to ensure that the coolant can be smoothly guided during the opening process, and to ensure that the end of the first cooling channel can be opened to the fine tool body 11 and connected to the sub-cooling channel 4 in the fine tool body 11. In this embodiment, the preferred angle α between the axis of the first cooling channel 5 and the central axis B of the main body is 45°.

[0035] In summary, the specific working process of the rotary tool is as follows: before the rotary tool is processed, it is necessary to select the corresponding adapter 9 to be installed in the cavity 13 of the tool body 1. After the installation, the tool body 1 needs to be fixedly connected to the machine tool. During the processing, the high-speed rotating rotary tool and the workpiece will generate a large amount of heat. At this time, it is necessary to introduce coolant from the end inlet of the adapter 9. The coolant flows from the cooling channel of the adapter 9 into the main cooling channel 3 arranged in the vertical section 212 of the screw 2. When the coolant flows to the end of the main cooling channel 3, it will be collected in the coolant collection chamber 7. At this time, the coolant in the coolant collection chamber 7 will be divided into two parts. One part of the coolant enters the annular cavity 8 after passing through the second cooling channel 6 opened radially outward, and cools the side wall of the tool body located in the annular cavity 8. The other part of the coolant enters the first cooling channel 5 opened forwardly. The coolant finally gathers at the end of the annular cavity 8 and enters the sub-cooling channel 4 through the inlet opened on the second wall 132. Finally, the corresponding rough cutting edge / fine cutting edge is cooled and lubricated through the outlet at the end of the sub-cooling channel 4.

Claims

1. A rotary tool comprising: A tool body (1) having a body central axis (B) defining a relative forward direction (DF) and a rearward direction (DR), and the tool body (1) is rotatable about the body central axis (B) in a rotational direction (R); A screw (2) is screwed into the corresponding central position of the tool body (1) at the front end side, thereby clamping the tool body (1) relative to the adapter / tool ​​handle, and correspondingly, the tool body (1) has a cavity (13) for the screw (2) to be screwed into; Features: Also included are: A main cooling channel (3) is provided in the center of the screw (2) and is directly connected to the cooling channel on the adapter / tool ​​handle; a coolant collection chamber (7), located downstream of the main cooling channel (3), for collecting coolant; and A sub-cooling channel (4) is provided on the tool body (1) and guides the coolant to the cutting area, and is connected to the coolant collecting chamber (7) through the primary cooling channel (5); the cross-sectional area of ​​the coolant collecting chamber (7) is larger than the cross-sectional area of ​​the sub-cooling channel (4).

2. The rotary tool according to claim 1, characterized in that: The tool body (1) is divided into a rough tool body (12) located at the rear and a fine tool body (11) located at the front, and the sub-cooling channel (4) is only provided on the fine tool body (11).

3. The rotary tool according to claim 2, characterized in that: An annular cavity (8) connected to the coolant collecting chamber (7) is formed between at least the structure of the screw (2) and the cavity (13); the annular cavity (8) is connected to the coolant collecting chamber (7) through a secondary cooling channel (6); the secondary cooling channel (6) is located upstream of the primary cooling channel (5); and the roughing tool body (12) is directly cooled through the annular cavity (8).

4. The rotary tool according to claim 3, characterized in that: The screw (2) comprises a main body (21) for arranging the primary cooling channel (3) and the secondary cooling channel, and an extension portion (22) located at the front end of the main body (21) and extending radially outward, wherein the extension portion (22) abuts against the front end side of the tool body (1) to close the front end of the annular cavity (8).

5. The rotary tool according to claim 4, characterized in that: The cross section of the main body (21) is in an inverted "T" shape, comprising a vertical section (212) for arranging the main cooling channel (3) and a transverse section (211) for arranging the first cooling channel (5) and the second cooling channel (6), and the extension portion (22) is located at the front end of the transverse section (211).

6. The rotary tool according to claim 5, characterized in that: The cavity (13) on the tool body (1) is surrounded by an annular inner step, and includes a first wall surface (131) located above the step and a second wall surface (132) located below the step. A central hole is provided in the center of the first wall surface (131) for the vertical section (212) to pass through, and the rear end of the transverse section (211) abuts against the first wall surface (131) to close the rear end of the annular cavity (8), and the gap between the side wall of the transverse section (211) and the second wall surface (132) constitutes the spatial area of ​​the annular cavity (8).

7. The rotary tool according to any one of claims 1 to 6, characterized in that: An included angle α is formed between the axis of the first cooling channel (5) and the central axis (B) of the main body, and the angle is 30°≤α≤60°.

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