Connecting mechanism for replaceable head tools that achieve high precision and high torque

Abstract

The present invention discloses a connection mechanism for a high-precision, high-torque interchangeable-head tool, comprising a cutter head and a tool shank, which are fixed to the tool shank by screws. The upper surface of the tool shank is provided with a cutter head mounting seat, and the outer side of the cutter head mounting seat is provided with three vertical surfaces separated by a distance, an arc surface between two adjacent vertical surfaces, and an arc-shaped conical surface above the arc surface. A groove is provided in the middle of each vertical surface, and the bottom edge of the groove is 0.5mm-2mm away from the upper surface of the tool shank; the inner side of the cutter head is provided with a cutter head vertical surface and a cutter head arc-shaped conical surface that are adapted to the vertical surface and the arc surface. The repeatability positioning accuracy of this solution can be controlled within 1.5 wires, which is far superior to 90% of interchangeable-head tools on the market; the powerful torque transmission force and high-precision repeatability positioning accuracy, as well as the low processing cost of the cutter head and long product life; the strong rigidity makes it difficult to cause damage to the cross section, and can be used for many large-allowance reaming processing needs.

Description

Technical Field

[0001] The present invention relates to the field of replaceable head tools, and in particular to a connecting mechanism of replaceable head tools capable of achieving high precision and high torque. Background Art

[0002] Tools can be divided into drills, milling cutters, reamers, reamers, boring tools, etc. according to their different uses. Each tool has a different purpose. For example, drills are used for drilling holes, milling cutters are used for slotting, reamers are used to enlarge holes and leave a certain amount of allowance for reaming, and reamers are used to finish the surface of the hole. While traditional tools can achieve high-precision repeatability (high-precision repeatability means that the reinstalled cutter head and the end face of the tool shank must fit tightly after each wear and tear (high-precision consistency in the axial and radial directions)), they suffer from insufficient torque transmission strength. This is because traditional replaceable-head tools basically rely on steel balls, tapered holes, and other methods to achieve repeatable positioning connection between the cutter head and the tool shank. Tapered holes and steel balls can only provide high-precision positioning and cannot provide strong torque transmission from the tool shank to the cutter head. Therefore, they all rely on screws to connect the cutter head and tool shank. Torque transmission depends entirely on screws, but the torque transmission strength of this type is not strong enough. When the machining allowance is large, the torque strength provided by the screws is insufficient and it is easy to damage. While traditional interchangeable-head tools offer sufficient torque transmission, their positioning accuracy is far from sufficient, making it difficult to achieve both high-precision repeatable positioning and strong torque transmission. Furthermore, there are no specialized interchangeable-head reaming tools on the market for traditional machining (mostly non-interchangeable-head reaming tools). Therefore, traditional reaming processes rely on solid alloy tools, welded tools, reamer drills, or boring tools. Summary of the Invention

[0003] In view of the above-mentioned defects or deficiencies in the prior art, it is desired to provide a connection mechanism for a replaceable head tool that can achieve high precision and high torque.

[0004] According to the technical solution provided in the embodiment of the present application, a connection mechanism of a high-precision, high-torque replaceable head tool can be realized, including a tool head and a tool rod, wherein the tool head and the tool rod are fixed by screws.

[0005] The upper surface of the knife bar is provided with a knife head mounting seat.

[0006] The outer side of the tool head mounting seat is provided with three vertical surfaces spaced apart from each other, an arc surface is formed between two adjacent vertical surfaces, an arc-shaped conical surface is formed above the arc surface, and a groove is formed in the middle of each vertical surface, and the bottom edge of the groove is 0.5mm-2mm away from the upper surface of the tool rod;

[0007] The inner side of the cutter head is provided with a cutter head vertical surface and a cutter head arc-shaped conical surface adapted to the vertical surface and the arc-shaped surface, and the inclination angle of the cutter head arc-shaped conical surface is 3 degrees to 45 degrees;

[0008] The height of the arc-shaped cone surface is 0.2mm-1.5mm;

[0009] The height of the cutter head mounting seat is 1mm-8mm;

[0010] The vertical surface of the cutter head and the arc-shaped conical surface of the cutter head form a mounting groove.

[0011] In this solution, further, among the three vertical surfaces, the lengths of the three surfaces are equal.

[0012] In this solution, further, among the three arc-shaped surfaces, the lengths of the arc surfaces of two surfaces are not equal to the length of the arc surface of the other surface.

[0013] In this solution, further, the knife rod is provided with a threaded hole, and the threaded hole is adapted to the screw.

[0014] In summary, the present invention has the following advantages over conventional replaceable head tools:

[0015] 1. The repeatability of this solution is much better than 90% of replaceable head tools on the market;

[0016] 2. Powerful torque transmission force and high-precision repeated positioning, low production cost of the cutter head, no need to grind the cutter head mounting groove (can be directly molded), and long tool rod service life;

[0017] 3. It has strong rigidity and is basically difficult to damage the cross section. It can be used for many large-allowance hole expansion processing needs.

[0018] 4. This technology can be used in the field of tool expansion, as well as in the field of processing replaceable head tools such as reamers and milling cutters.

[0019] 5. This technology has created a replaceable head reaming tool (all reaming tools on the market are not replaceable heads). The replaceable head reaming tool has the following advantages over the existing non-replaceable head reaming tools:

[0020] (1) Save a lot of processing operation and tool management costs;

[0021] (2) Reduce the amount of carbide material used in the cutter body;

[0022] (3) Longer tool life and predictability of hole machining;

[0023] (4) Better comprehensive tool inventory management;

[0024] (5) Eliminates the need for re-grinding, returning, and back-up tool mobility of reamer tools;

[0025] (6) The tool installation time is greatly shortened because the tool head is replaced on the machine tool and tool holder, without the need for pre-adjustment, compensation and tool setting.

[0026] (7) Lower cost for deep hole processing.

[0027] (8) Customized sizes are no longer required, and procurement costs and cycles are greatly reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Other features, objects and advantages of the present application will become more apparent upon reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0029] Figure 1 Schematic diagram of the structure of the tool bar in the present invention;

[0030] Figure 2 Schematic diagram of the structure of the cutter head in the present invention;

[0031] Figure 3 The figure shows the structure of the cutter head and the cutter rod after installation in the present invention.

[0032] Numbers in the figure: cutter head 1; cutter bar 2; vertical surface 3; screw 4; curved surface 5; slot 6; mounting slot 7; threaded hole 8; cutter head mounting seat 9, curved conical surface 10, cutter head vertical surface 11, cutter head curved conical surface 12 DETAILED DESCRIPTION

[0033] The present application will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the relevant invention and are not intended to limit the invention. It should also be noted that, for ease of description, only portions relevant to the invention are shown in the accompanying drawings.

[0034] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0035] like Figure 1 、 Figure 2 and Figure 3 As shown, a connection mechanism for a replaceable head tool that can achieve high precision and high torque is provided. A mounting groove 7 is provided on the tool head 1, and the edges of the mounting groove 7 are a tool head vertical surface 11 and a tool head arc-shaped conical surface 12.

[0036] Installation method: Install the cutter head 1 on the tool rod 2 in the direction that adapts to the mounting seat 9, and then use a screw 4 to pass through the mounting groove of the cutter head 1 and the threaded hole 8 of the cutter head 2 to connect the two. When the screw 4 is continuously tightened, the three arcuate conical surfaces 12 of the mounting groove 7 of the cutter head 1 will come into conical contact with the three arcuate conical surfaces 10 on the outside of the mounting seat 9 on the tool rod 2, and as the screw 4 is tightened, the three arcuate conical surfaces on the mounting groove 7 and the mounting seat 9 will be slightly deformed due to mutual extrusion. In order to make the deformation of the arcuate conical surface greater (the greater the deformation, the higher the positioning accuracy), three grooves 6 will be opened in the middle section of the three vertical surfaces 3 of the mounting seat 9. The purpose of these three grooves 6 is to make it easier for the mounting seat 9 to deform under force when the three arcuate conical surfaces 10 on the tool rod 2 are squeezed by the three arcuate conical surfaces 12 on the cutter head, thereby realizing the function of high-precision repeated positioning. The deformation mentioned here refers to elastic deformation (not plastic deformation), that is, when the cutter head is removed, the arc-shaped conical surface 10 will still rebound to its original state, so as to achieve the high-precision repeatable positioning requirement when the cutter head 1 is installed next time. The arc-shaped surface 5 further down is an arc-shaped surface without taper (taper refers to the inclination angle of the cone surface). After testing, this kind of arc-shaped surface 5 without taper is basically difficult to deform, so when the entire cutter head 1 is pressed onto the mounting seat 9, the tool is installed. The reason why this technology only leaves a deformable arc-shaped conical surface 10 of 0.2mm-1.5mm is that the less the deformed surface of the cutter head 1 and the tool rod 2 contacts, the higher the positioning accuracy.

[0037] The three slots 6 cannot be cut to the bottom of the vertical surface 3. The bottom edge of the slot 6 is 0.5mm-2mm away from the upper surface of the tool shank 2. If the bottom edge of the slot 6 is cut to the bottom, it will affect the rigidity of the mounting base 9, thereby reducing the torque transmission force. Therefore, a certain height below the slot 6 must be left ungrooved so as not to affect the rigidity and torque transmission of the bottom of the mounting base 9. When the screw 4 is tightened, the nut of the slot 6 is pressed against the protruding cross section of the mounting slot 7 of the cutter head 1, thus achieving a tight connection between the cutter head 1 and the tool shank 2.

[0038] This connection method can control the repeat positioning accuracy of the cutter head 1 and the tool rod 2 within 1.5 wires. The most important thing is that it can also bring great torque transmission force under such precision. This is an advantage that traditional exchangeable head tools such as expanders, reamers, and milling cutters do not have. In addition, another great advantage of this technology is that the cost is more advantageous than traditional tools. Because in order for the traditional exchangeable cutter head 1 to achieve high-precision repeat positioning function with the tool rod 2, it is necessary to grind a high-precision inner circle with a tapered surface in the hollow interior of the cutter head 1. This kind of grinding is very time-consuming and labor-intensive, and requires very high costs. Now the hollow mounting groove 7 of the cutter head does not need to be polished, and can be directly completed by molding. The processing cost is very low and the mold opening is also easy. Therefore, the production cost of this cutter head 1 is much cheaper than the traditional cutter head 1 which requires high-precision grinding.

[0039] In this solution, in order to ensure that the cutter head 1 can only be installed on the tool rod 2 in one direction, the method adopted is to make the three vertical surfaces 3 equal in length and the three arc-shaped surfaces 5 of unequal length. In this way, the cutter head 1 can only be installed in the tool rod in an adaptive manner, and the torque transmission force of the three vertical surfaces can be ensured to be the most uniform (because the three vertical surfaces are equal in length). Therefore, the cutter head 1 and the tool rod 2 can only be installed in a single direction, and are installed in a single direction during the manufacturing process and the use process, thereby further improving the repeatability accuracy.

[0040] In this solution, the taper of the arc-shaped conical surface 12 of the cutter head 1 is 3 degrees to 45 degrees; the reason for choosing this angle of 3 degrees to 45 degrees is that when the angle is less than 3 degrees, the 0 When the angle is greater than 45 degrees, the centering effect will be worse and the deformation of the mounting seat 9 will be greater. When the deformation is too large, the deformation will become plastic deformation, which will lose the original intention of high repeat positioning accuracy required by this technology. Therefore, a value of 3 to 45 degrees is more appropriate.

[0041] A curved surface is a portion of the outer surface of a cylinder, and a curved conical surface is a portion of the outer surface of a cone. The reason for choosing a curved conical surface for positioning connections is that it is easily deformed by force and can achieve high-precision positioning connections.

[0042] The three functional points achieved by this solution are mainly high-precision repeated positioning, strong torque force, and orientation.

[0043] High-precision repeatable positioning is mainly achieved by the arc-shaped conical surfaces on the cutter head 1 and the tool rod 2 squeezing each other and generating a slight elastic deformation when the screw 4 is tightened; because it must be ensured that the end faces of the cutter head 1 and the tool rod 2 are tightly fitted (axial and radial consistency) after each replacement of the cutter head.

[0044] Torque transmission means that the shank 2 can provide sufficient driving force to the cutter head 1 when it rotates. This is achieved by relying on the three vertical surfaces on the cutter head 1 and the shank 2. The vertical surface means that the vertical surface is perpendicular to the cross section of the shank or cutter head. The vertical surface can transmit the most powerful torque.

[0045] Orientation means that the cutter head 1 can only be installed on the tool arbor 2 mounting seat facing a certain fixed direction. This is achieved by ensuring that the lengths of the three vertical surfaces are equal and the lengths of the three arc-shaped surfaces are unequal. The purpose is to further improve the repeatability of the positioning between the cutter head and the tool arbor.

[0046] The advantages of the replaceable head reamer compared with the existing reamer are shown in the following table:

[0047]

[0048] The above description is merely an illustration of the preferred embodiments of the present application and the technical principles employed. The scope of the invention herein is not limited to the technical solutions formed by the specific combination of the aforementioned technical features, but also encompasses other technical solutions formed by any combination of the aforementioned technical features or their equivalents without departing from the inventive concept. For example, a technical solution formed by replacing the aforementioned features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. A connection mechanism for a high-precision, high-torque replaceable head tool, comprising a tool head (1) and a tool bar (2), wherein the tool head (1) and the tool bar (2) are fixed by screws (4), and is characterized by: A cutter head mounting seat (9) is provided on the upper surface of the cutter bar (2), and the height of the cutter head mounting seat (9) is 1 mm to 8 mm; The outside of the tool head mounting seat (9) is provided with three mutually spaced planar vertical surfaces (3), each vertical surface (3) is perpendicular to the upper surface of the tool rod (2), an arc surface (5) is between two adjacent vertical surfaces (3), and an arc-shaped conical surface (10) is above the arc surface (5), and a groove (6) is provided in the middle of each vertical surface (3), and the bottom edge of the groove (6) is 0.5mm-2mm away from the upper surface of the tool rod (2); The inner side of the cutter head (1) is provided with a cutter head vertical surface (11) and a cutter head arcuate conical surface (12) adapted to the vertical surface (3) and the arcuate surface (5); the inclination angle of the cutter head arcuate conical surface (12) is 3 degrees to 45 degrees; the lengths of the three vertical surfaces (3) are equal; the lengths of the arcuate surfaces of two surfaces are not equal to the length of the arcuate surface of the other surface; The opening position of the groove (6) enables the arc-shaped conical surface (10) to undergo elastic deformation when the screw (4) is tightened to achieve radial positioning; The vertical surface (11) of the cutter head and the arc-shaped conical surface (12) of the cutter head (1) form a mounting groove (7), and the height of the arc-shaped conical surface (10) is 0.2 mm-1.5 mm.

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