Cutter locking structure

Abstract

The invention belongs to the technical field of cutter disassembly and assembly, and particularly relates to a cutter locking structure which comprises a cutter and a cutter handle, and a cam tensioning mechanism is arranged between the cutter and the cutter handle. The cam tensioning mechanism comprises a lock shaft and an eccentric wheel installed on the lock shaft, an axial tensioning piece is arranged between the cutter and the cutter handle, the axial tensioning piece is movably assembled in the cutter handle, one end of the axial tensioning piece is in threaded connection with the cutter, and a tensioning hole is formed in the axial tensioning piece; or a tensioning hole is formed in the short taper shank of the cutter; the axis of the tensioning hole coincides with the central axis of the cutter handle and is perpendicular to the axis of the lock shaft. The lock shaft can rotate relative to the cutter handle, penetrates into the cutter handle and is connected with the tensioning hole in an inserted mode so that the eccentric wheel can be located in the tensioning hole, the eccentric outer side of the eccentric wheel makes contact with the hole wall of the tensioning hole, and the eccentric wheel drives the cutter to move in the axial direction of the eccentric wheel under rotation of the lock shaft so as to tension the cutter. And a locking structure is arranged between the lock shaft and the knife handle. The tool can be prevented from loosening and rotating relative to the tool handle, machining precision is guaranteed, machining efficiency is improved, and machining cost is saved.

Description

Technical Field

[0001] The present invention belongs to the technical field of tool disassembly and assembly, and particularly relates to a tool locking structure. Background Art

[0002] The short cone connection structure has the characteristics of high precision, high rigidity, fast loading and unloading, etc., and is widely used in the connection between tools and tool holders.

[0003] In the field of mechanical connection, especially in the occasions involving high-precision transmission and positioning, the short cone connection structure is usually adopted, such as the assembly of a tool holder and a ball head. As a common short cone connection structure, the ball head taper shank connection structure usually adopts the form of double-headed stud threaded connection. Its core principle is to axially tighten the tool holder and the ball head through a double-headed stud with reverse threads at both ends. The specific structure is as Figure 1 shown. External threads with opposite helix directions are respectively machined at both ends of the double-headed stud 103. The external thread at one end is matched with the internal threaded hole of the tool holder 102, and the external thread at the other end is matched with the internal threaded hole of the short cone on the ball head 101. By rotating the double-headed stud, pre-tightening forces are generated simultaneously at both ends of the thread, and the ball head short cone and the tool holder are axially tightened.

[0004] The advantages of adopting the double-headed stud connection method are as follows: 1. The structure is simple, and the connection can be realized only by the stud and the threaded hole; 2. The cost is low. The thread processing technology is mature and it is easy to produce standardized products; 3. The axial positioning is reliable, and the conical surface fit can provide relatively high radial stiffness.

[0005] Although the double-headed stud connection is widely used, it also exposes significant defects in practical applications. Since the threads at both ends of the double-headed stud rotate in opposite directions, under high-speed rotation or alternating loads, the reverse threads at both ends of the double-headed stud will loosen on one side or even completely fail due to uneven stress, and the disassembly and assembly of the tool need to be carried out frequently; only the conical surface friction between the short cone ball head and the tool holder resists the torque. If the pre-tightening force is insufficient or the contact surface is worn, relative rotation between the tool and the tool holder is likely to occur. The above defects are likely to lead to a reduction in machining accuracy, a reduction in machining efficiency, and an increase in machining cost. Summary of the Invention

[0006] The purpose of the present invention is to provide a tool locking structure to solve the technical problems of easy reduction in machining accuracy, reduction in machining efficiency, and increase in machining cost when the short cone connection structure adopts the traditional double-headed bolt connection.

[0007] To solve the above problems, the tool locking structure provided by the present invention adopts the following technical solutions: A tool locking structure, including a tool and a tool holder, and a cam tensioning mechanism is provided between the tool and the tool holder; The cam tightening mechanism includes a locking shaft and an eccentric wheel mounted on the locking shaft; An axial tensioning member is provided between the tool and the tool holder. The axial tensioning member is movably assembled in the tool holder and is threadedly connected to the tool at one end. A tensioning hole is provided on the axial tensioning member; alternatively, a tensioning hole is provided on the short taper shank of the tool; the axis of the tensioning hole is perpendicular to the central axis of the tool holder; The locking shaft can rotate relative to the tool holder, and the locking shaft penetrates into the tool holder and is inserted into the tensioning hole, so that the eccentric wheel is located in the tensioning hole. The eccentric outer side of the eccentric wheel contacts the hole wall of the tensioning hole. The eccentric wheel drives the tool to move axially along it to tighten the tool when the locking shaft rotates; A locking structure is provided between the locking shaft and the tool holder for locking the locking shaft when it rotates in place.

[0008] The beneficial effects are as follows: The present invention uses a cam tightening mechanism to replace the traditional double-headed stud connection method, directly tightens the tool or indirectly tightens the tool through an axial tensioning member, relies on the geometric shape of the eccentric wheel in the cam tightening mechanism to transmit force, does not rely on friction, reduces the risk of thread loosening that occurs with double-headed studs, and improves connection stability. In addition, the contact between the eccentric wheel and the tensioning hole is a line contact, which can evenly distribute the load. Compared with the point contact of the traditional thread, it can reduce local stress concentration; when the camshaft is inserted into the tensioning hole along the radial direction of the tool holder, it is perpendicular to the rotation direction of the tool, so it can prevent the tool from rotating relative to the tool holder and improve the working stability of the tool; furthermore, the tool can be tightened by rotating the camshaft, and the locking structure ensures that the camshaft is locked after rotating in place to prevent accidental loosening, without repeatedly screwing the thread, and can realize the quick disassembly and assembly of the tool. The tool locking structure of the present invention can ensure the stable operation of the tool during the machining process, ensure the machining accuracy, avoid frequent disassembly and assembly, ensure the machining efficiency, and save the machining cost.

[0009] Further, the tool holder is provided with a socket for the locking shaft to be inserted. The locking structure includes a limiting protrusion and a protrusion platform provided in the socket, a blocking protrusion and a retaining ring provided on the locking shaft, and a retaining member provided on the tool holder; a relief groove for avoiding the limiting protrusion is provided on the retaining ring. The limiting protrusion and the protrusion platform are arranged at intervals in the axial direction of the socket for the retaining ring to be placed; the protrusion platform has a first blocking portion and a second blocking portion, and the retaining member has elasticity and is arranged between the first blocking portion and the second blocking portion; when the blocking protrusion is in blocking cooperation with the first blocking portion, the locking shaft is in the unlocked position. When the blocking protrusion crosses the retaining member during the rotation of the locking shaft and is in blocking cooperation with the second blocking portion, the locking shaft is in the locked position; the retaining member is used to block the blocking protrusion when the blocking protrusion is in the locked position; the limiting protrusion is used to be in blocking cooperation with the retaining ring in the axial direction of the socket.

[0010] Beneficial effects: The limiting protrusion can be in blocking cooperation with the retaining ring during the rotation of the locking shaft, which can limit the radial movement of the locking shaft and prevent the eccentric wheel from disengaging from the tensioning hole; by providing a raised platform, the installation and locking of the locking shaft can be achieved quickly; the anti-rotation part prevents accidental rotation when the locking shaft rotates in place, that is, when the tool is tensioned in place, enhances the locking reliability, and ensures the stability of the tool connection.

[0011] Further, the first blocking portion is a blocking inclined surface, and the second blocking portion is a blocking curved surface; on both sides of the blocking protrusion, there are respectively a mating inclined surface matching the blocking inclined surface and a mating inclined surface matching the blocking curved surface.

[0012] Beneficial effects: The design of the blocking inclined surface and the blocking curved surface enables the locking shaft to smoothly switch between the unlocking and locking states during rotation, reducing the operating force. In addition, the blocking curved surface can increase the mating contact area between the blocking protrusion and the second blocking portion, ensuring the locking reliability of the locking shaft. The blocking inclined surface guides the blocking protrusion and automatically pushes the locking shaft outwards by a small distance, facilitating the quick disassembly of the locking shaft.

[0013] Further, the anti-rotation part is an elastic cylindrical pin.

[0014] Beneficial effects: The elastic cylindrical pin occupies a small space, can be adapted to the narrow space inside the tool holder, is convenient for installation, and can provide reliable elastic resistance. In addition, the elastic cylindrical pin is a standardized part, which is easy to purchase and replace.

[0015] Further, the eccentric wheel and the locking shaft are integrally formed.

[0016] Beneficial effects: The number of assembly steps is reduced, the coaxiality error during the connection of multiple components is avoided, and the synchronous rotation of the eccentric wheel and the locking shaft is ensured; integral forming can reduce weak links, improve the overall rigidity, reduce the risk of loosening, and is suitable for high-speed rotation scenarios.

[0017] Further, the eccentric wheel is cylindrical.

[0018] Beneficial effects: The contact between the cylindrical surface and the tensioning hole is line contact, which evenly distributes the load and reduces local stress concentration. The cylindrical surface can be manufactured with high precision through milling process, reducing the manufacturing cost.

[0019] Further, the inner side of the eccentricity of the eccentric wheel is tangent to the outer surface of the locking shaft.

[0020] Beneficial effects: The inscribed design minimizes the radial dimension of the overall structure, saves space, and is suitable for narrow environments such as tool holders. During processing, a standard milling cutter can be used for one-time forming, simplifying the manufacturing process.

[0021] Further, a tool interface is provided at the end of the locking shaft.

[0022] Beneficial effects: It is convenient to use tools (such as wrenches) to rotate the lock shaft, improving the operation convenience. The interface can be standardized to adapt to a variety of tools, enhancing the versatility.

[0023] One of the technical solutions is that an axial tensioning member is provided between the tool and the tool holder, there is one cam tensioning mechanism, the tensioning hole is a through hole, and the lock shaft passes through the tensioning hole and is inserted into the insertion hole.

[0024] Beneficial effects: When using a single cam tensioning mechanism, the structure can be simplified, the number of parts can be reduced, and the length of the tool holder can be shortened. The through hole design facilitates the installation and positioning of the lock shaft, eliminating the need for complex alignment steps and improving the assembly efficiency.

[0025] Another technical solution is that two axially arranged tensioning holes are provided on the short taper shank of the tool, the tensioning holes are blind holes, and there are two cam tensioning mechanisms.

[0026] Beneficial effects: The double cam tensioning mechanisms act synchronously, can provide a greater tensioning force, enhance the anti-torsion ability, and improve the connection stability between the tool and the tool holder. Description of the Drawings

[0027] Figure 1 It is a schematic diagram of a ball nose taper shank connection structure using a stud in the prior art; Figure 2 It is a three-dimensional structure schematic diagram of Embodiment 1 of the tool locking structure of the present invention; Figure 3 It is Figure 2 front view of Figure 4 It is Figure 3 A-A cross-sectional view of Figure 5 It is a three-dimensional structure schematic diagram of the tool holder in Embodiment 1 of the tool locking structure of the present invention; Figure 6 It is Figure 5 enlarged schematic diagram at A in Figure 7 It is a three-dimensional structure schematic diagram of the axial tensioning member in Embodiment 1 of the tool locking structure of the present invention; Figure 8 It is a front view of the axial tensioning member in Embodiment 1 of the tool locking structure of the present invention; Figure 9 It is a three-dimensional structure schematic diagram of the cam tensioning mechanism in Embodiment 1 of the tool locking structure of the present invention; Figure 10 It is Figure 9 front view of Figure 11 It is Figure 9 left side view of Figure 12is Figure 9 the right side view of; Figure 13 is a schematic structural view of Embodiment 2 of the tool locking structure of the present invention; Figure 14 is Figure 13 the B-B sectional view of; Figure 15 is a schematic structural view of the cam tensioning mechanism in Embodiment 2 of the tool locking structure of the present invention; Figure 16 is a schematic structural view of the tool in Embodiment 2 of the tool locking structure of the present invention.

[0028] Explanation of reference numerals: 101, ball head; 102, stud; 103, tool shank; 1, tool; 2, tool shank; 21, jack; 22, limit projection; 23, raised platform; 24, first stop portion; 25, second stop portion; 26, anti-backlash groove; 3, cam tensioning mechanism; 31, locking shaft; 311, tool interface; 32, eccentric wheel; 33, retaining ring; 34, relief groove; 35, stop projection; 351, mating inclined surface; 352, mating curved surface; 4, axial tensioning member; 41, tensioning hole; 42, external thread section; 43, water inlet guiding hole; 5, anti-backlash member; 201, tool; 2011, taper shank; 2012, tensioning hole; 202, tool shank; 203, cam tensioning mechanism; 2031, locking shaft; 2032, eccentric wheel. Detailed implementation manners

[0029] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Those skilled in the art should know that the embodiments described below are a part of the embodiments of the present disclosure, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts fall within the scope of protection of the present invention.

[0030] Next, the principles and spirits of the present invention will be elaborated in detail with reference to several representative embodiments of the present invention.

[0031] Embodiment 1 of the tool locking structure provided by the present invention: As Figure 2 and Figure 3 shown, the tool 1 locking structure includes a tool 1, an axial tensioning member 4, a tool shank 2, and a cam tensioning mechanism 3.

[0032] Specifically, the tool 1 is a tension-type tool with a taper shank structure, and a threaded hole is provided in the taper shank of the tool 1. In this embodiment, the tool 1 is with Figure 2Taking the ball-end milling cutter shown as an example for demonstration, however, the cutter 1 described in the present invention is not limited to the ball-end milling cutter, and any tension-type cutter with a taper shank structure is applicable.

[0033] As Figure 5 and Figure 6 shown, the tool holder 2 is a tension-type tool holder 2 that matches the cutter 1. The tool holder 2 is provided with an insertion hole 21 extending along its radial direction, and the insertion hole 21 penetrates through the tool holder 2. One end of the insertion hole 21 has a larger diameter, and the other end has a smaller diameter. The tool holder 2 is also provided with a retaining groove 26 on the side where the insertion hole 21 has a larger diameter, and the retaining groove 26 communicates with the insertion hole 21.

[0034] As Figure 4 , Figure 7 and Figure 8 shown, the axial tension member 4 is assembled inside the tool holder 2, has a symmetrical structure, and can move along the central axis of the tool holder 2. One end of the axial tension member 4 is an external thread section 42 for threaded connection with the taper shank of the cutter 1. The other end of the axial tension member 4 is provided with a tension hole 41, the tension hole 41 is a through hole, and the hole diameter is larger than the hole diameter of the insertion hole 21; the axis of the tension hole 41 is perpendicular to the axis of the axial tension member 4.

[0035] The axial tension member 4 is also provided with a water inlet guiding hole 43 at the position between the external thread section 42 and the tension hole 41. The water inlet guiding hole 43 is a through hole, the axis of the water inlet guiding hole 43 is perpendicular to the axis of the tension hole 41, and coincides with the central axis of the tool holder 2. The axial tension member 4 is coaxially provided with a central water inlet hole, the central water inlet hole communicates with the water inlet guiding hole 43, and one end of the central water inlet hole extends to the end face of the external thread section 42. After the axial tension member 4 is connected to the cutter 1, cooling water can be introduced into the central water inlet hole through the water inlet guiding hole 43, and then the cooling water can be guided into the cooling channel inside the cutter 1 to cool the cutter 1 during the working process of the cutter 1.

[0036] In this embodiment, as Figure 4 shown, one cam tension mechanism 3 is provided and is connected between the tool holder 2 and the axial tension member 4. Specifically, the cam tension mechanism 3 has an integrally formed structure. As Figure 9 shown, it includes an integrally formed locking shaft 31, an eccentric wheel 32 located on the locking shaft 31, a retaining ring 33 located on the locking shaft 31, and a retaining protrusion 35.

[0037] As Figure 10 shown, the locking shaft 31 has a three-section structure, including a head section, an intermediate shaft section, and a mating shaft section. The outer diameter of the head section is larger than the outer diameter of the mating shaft section, and the outer diameter of the mating shaft section is larger than the outer diameter of the intermediate shaft section. As Figure 11As shown, a tool interface 311 is provided on the head section. The tool interface 311 is a standard hexagonal interface and can cooperate with tools such as wrenches. The retaining ring 33 is coaxially arranged on the head section, and an arc-shaped avoidance groove 34 is provided on the retaining ring 33; a retaining protrusion 35 connected to the head is provided below the retaining ring 33.

[0038] As Figure 10 shown, the eccentric wheel 32 is located on the intermediate shaft section and is cylindrical. As Figure 12 shown, the inner side of the eccentricity of the eccentric wheel 32 is tangent to the outer surface of the locking shaft 31. Here, the tangency means that the circle formed by the projection of the eccentric wheel 32 on the axis of the locking shaft 31 is internally tangent to the circle formed by the projection of the mating shaft section on the axis of the locking shaft 31. During processing, a standard milling cutter can be used for one-time machining, without repeated positioning, simplifying the manufacturing process.

[0039] As Figure 4 shown, the locking shaft 31 is inserted from the side with a larger diameter of the insertion hole 21 on the tool handle 2, passes through the tensioning hole 41, and is inserted into the part with a smaller diameter of the insertion hole 21. The locking shaft 31 can rotate within the insertion hole 21. When the locking shaft 31 is inserted into the insertion hole 21, the eccentric wheel 32 is located within the tensioning hole 41, and the outer side of the eccentricity of the eccentric wheel 32 contacts the hole wall of the tensioning hole 41. Limit protrusions 22 and a protrusion platform 23 are provided in the insertion hole 21. The limit protrusions 22 and the protrusion platform 23 are arranged at intervals in the axial direction of the insertion hole 21, and the limit protrusions 22 are located on the outer side, and the protrusion platform 23 is located on the inner side. The avoidance groove 34 on the retaining ring 33 is used to avoid the limit protrusion 22, and at the same time, the limit protrusion 22 can be in a retaining fit with the retaining ring 33 in the axial direction of the insertion hole 21.

[0040] As Figure 6 shown, the protrusion platform 23 has a first retaining portion 24 and a second retaining portion 25. The first retaining portion 24 is a retaining inclined surface, and the second retaining portion 25 is a retaining curved surface. Matching inclined surfaces 351 matching the retaining inclined surface and matching curved surfaces 352 matching the retaining curved surface are respectively provided on both sides of the retaining protrusion 35. A retaining groove 26 is located between the first retaining portion 24 and the second retaining portion 25 and is close to the position of the second retaining portion 25. A retaining member 5 is installed in the retaining groove 26. The retaining member 5 has elasticity. In this embodiment, the retaining member 5 uses a spring cylindrical pin, and the elastic cylindrical pin is a standardized part, which is easy to purchase and replace.

[0041] The limit protrusions 22, the protrusion platform 23, the retaining member 5, the retaining protrusion 35, and the retaining ring 33 together form a locking structure for locking the locking shaft 31 when it rotates in place. When the retaining protrusion 35 is in a retaining fit with the first retaining portion 24, the locking shaft 31 is in the unlocked position; when the retaining protrusion 35 is in a retaining fit with the second retaining portion 25, the locking shaft 31 is in the locked position.

[0042] The specific usage method of the locking structure of the tool 1 of the present invention is: First, thread-connect the cutting tool 1 with the axial tensioning member 4. Then, align the relief groove 34 on the retaining ring 33 with the limiting protrusion 22. Insert the locking shaft 31 into the insertion hole 21 and pass through the tensioning hole 41 of the axial tensioning member 4. At this time, the retaining ring 33 passes over the limiting protrusion 22 and is located between the limiting protrusion 22 and the protrusion platform 23, and the eccentric wheel 32 contacts the hole wall of the tensioning hole 41. Then, insert a wrench into the tool interface 311 to rotate the locking shaft 31. Under the action of the eccentric wheel 32, the axial tensioning member 4 moves along the central axis direction of the tool shank 2 to pull the cutting tool 1 to move axially. During the rotation of the locking shaft 31, when the blocking protrusion 35 passes over the anti-retreat member 5 and engages with the second blocking portion 25, the tensioning is in place. At this time, the blocking protrusion 35 is blocked by the anti-retreat member 5 and will not retreat. At the same time, the cutting tool 1 and the tool shank 2 are blocked in the central axis direction of the tool shank 2. The eccentric wheel 32 still contacts the hole wall of the tensioning hole 41, and the eccentric wheel 32 blocks the axial tensioning member 4 in the central axis direction of the tool shank 2, restricting the movement of the axial tensioning member 4 and thus restricting the movement of the cutting tool 1 in two directions, realizing the reliable fixation of the cutting tool 1 and the tool shank 2. Since the locking shaft 31 passes through the axial tensioning member 4 in a direction perpendicular to the central axis of the tool shank 2, that is, there is no relative rotation between the axial tensioning member 4 and the tool shank 2, and thus there is no relative rotation between the cutting tool 1 and the tool shank 2.

[0043] When the cutting tool 1 is severely worn after long-term use and needs to be disassembled, the operator uses a wrench to cooperate with the tool interface 311 to reverse-rotate the locking shaft 31, so that the blocking protrusion 35 passes over the anti-retreat member 5 until it rotates to the position of the first blocking portion 24. During this process, the eccentric wheel 32 rotates together with the locking shaft 31, driving the axial tensioning member 4 to move in the reverse direction, so that the cutting tool 1 is separated from the tool shank 2. Then, the cutting tool 1 can be unscrewed from the axial tensioning member 4 for replacement.

[0044] Compared with the existing connection method of double-headed studs, the present invention can realize the quick disassembly and assembly of the cutting tool 1. When the installed cutting tool 1 is working, it will not rotate relative to the tool shank 2, and under the tension of the eccentric wheel 32, it is not easy to loosen, reducing the risk of the cutting tool 1 falling off from the tool shank 2, thereby ensuring the machining accuracy of the cutting tool 1, reducing the disassembly and assembly frequency of the cutting tool 1, and saving the machining cost.

[0045] It should be noted that in practice, two sets of cam tensioning mechanisms can also be set to synchronously tension the axial tensioning member. At this time, the tensioning holes on the axial tensioning member are in the form of two coaxially arranged blind holes.

[0046] Embodiment 2 of the tool locking structure provided by the present invention: The main difference from Embodiment 1 is that: In Embodiment 1, there is one cam tensioning mechanism 3, and it is necessary to use the axial tensioning member 4 to realize the tensioning of the cutting tool.

[0047] In this embodiment, the axial tensioning member 4 is not provided, and two sets of cam tensioning mechanisms 203 are provided. Specifically, as shown in Figure 13 , Figure 14 , Figure 15 and Figure 16 , two tensioning holes 2012 arranged coaxially are provided on the taper shank 2011 of the cutting tool 201. These two tensioning holes 2012 are both blind holes, and the two sets of cam tensioning mechanisms 203 respectively correspond to the tensioning holes 2012 one by one. Each cam tensioning mechanism 203 still includes a locking shaft 2031, an eccentric wheel 2032 located on the locking shaft 2031, a retaining ring and a retaining protrusion located on the locking shaft 2031. However, the length of the locking shaft 2031 is smaller than the length of the locking shaft 31 in the above-mentioned Embodiment 1 and is adapted to the depth of the tensioning hole 2012. In this embodiment, the locking shaft 2031 is a two-section structure, only the head section and the middle section. The eccentric wheel 2032 is still installed on the middle section, but the end face of the eccentric wheel 2032 is flush with the end face of the locking shaft 2031. It should be noted that the length of the locking shaft 2031 is designed to match the depth of the tensioning hole 2012 and is not specifically limited.

[0048] At this time, the calibers on both sides of the jack provided on the tool shank 202 are the same, and a limiting protrusion, an anti-backlash groove and a raised platform are provided on each side of the jack.

[0049] During installation, the two locking shafts 2031 need to be inserted into the corresponding tensioning holes 2012 through both sides of the jack respectively, and the locking shafts 2031 are screwed from both sides at the same time. At this time, the two eccentric wheels 2032 drive the cutting tool 201 to move axially together until the cutting tool 201 is tensioned in place.

[0050] In this embodiment, two sets of cam tensioning mechanisms 203 act synchronously, which can provide a greater tensioning force, enhance the anti-torsion ability, and improve the connection stability between the cutting tool 201 and the tool shank 202; when two sets of cam tensioning mechanisms 203 are used, there is no need to provide an axial tensioning member 4, and the size of the locking shaft 2031 is also correspondingly reduced..

[0051] Embodiment 3 of the tool locking structure provided by the present invention: The main difference from Embodiment 1 is that: In Embodiment 1, the shape of the eccentric wheel is cylindrical.

[0052] In this embodiment, the eccentric wheel adopts a common cam. At this time, the cam is connected to the middle section of the locking shaft, and the eccentric inner side of the cam is located outside the outer surface of the locking shaft and does not tangent to the outer surface of the locking shaft.

[0053] Embodiment 4 of the tool locking structure provided by the present invention: The main difference from Embodiment 1 is that: In Embodiment 1, the eccentric wheel and the locking shaft are integrally machined.

[0054] In this embodiment, the eccentric wheel and the locking shaft are two parts. The eccentric wheel is sleeved on the locking shaft, and the two are connected by welding.

[0055] Embodiment 5 of the tool locking structure provided by the present invention: The main difference between it and Embodiment 1 lies in: In Embodiment 1, the limiting protrusion is used to block the retaining ring, and the anti-retreat member is used to prevent the blocking protrusion from retreating to fix the locking shaft.

[0056] In this embodiment, an internal thread is machined on the side with a smaller diameter of the jack, and an external thread is machined on the mating section of the locking shaft. The mating section of the locking shaft is threadedly connected to the above internal thread. Since the mating section of the locking shaft is threadedly mated with the side with a smaller diameter of the jack, it needs to be screwed. During the screwing process, it just drives the rotation of the eccentric wheel to realize the tightening of the tool.

[0057] Based on the above description of this specification, those skilled in the art can also understand the following terms used. For example, terms indicating orientation or positional relationship such as "inner" and "outer" are based on the orientation or positional relationship shown in the drawings of this specification. It is only for the purpose of facilitating the description of the solution of the present invention and simplifying the description, rather than explicitly or implicitly indicating that the device or element involved must have the specific orientation, be constructed and operate in the specific orientation. Therefore, the above terms of orientation or positional relationship cannot be understood or interpreted as a limitation to the solution of the present invention.

[0058] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. Tool locking structure, including a tool and a tool holder, characterized in that, A cam tightening mechanism is provided between the cutting tool and the tool holder; The cam tightening mechanism includes a locking shaft and an eccentric wheel mounted on the locking shaft; An axial tensioning member is provided between the cutting tool and the tool holder. The axial tensioning member is movably assembled in the tool holder and is threadedly connected to the cutting tool at one end. A tensioning hole is provided on the axial tensioning member; alternatively, a tensioning hole is provided on the short taper shank of the cutting tool; the axis of the tensioning hole is perpendicular to the central axis of the tool holder; The locking shaft can rotate relative to the tool holder, and the locking shaft penetrates into the tool holder and is inserted into the tensioning hole, so that the eccentric wheel is located in the tensioning hole. The eccentric outer side of the eccentric wheel contacts the hole wall of the tensioning hole. The eccentric wheel drives the cutting tool to move axially along it to tighten the cutting tool when the locking shaft rotates; A locking structure is provided between the locking shaft and the tool holder for locking the locking shaft when it rotates in place.

2. The tool locking structure according to claim 1, characterized in that, A socket for inserting the locking shaft is provided on the tool holder. The locking structure includes a limiting protrusion and a protrusion platform provided in the socket, a blocking protrusion and a retaining ring provided on the locking shaft, and a retaining member provided on the tool holder; a relief groove for avoiding the limiting protrusion is provided on the retaining ring. The limiting protrusion and the protrusion platform are arranged at intervals in the axial direction of the socket for the retaining ring to be placed in; The protrusion platform has a first blocking portion and a second blocking portion. The retaining member is elastic and is arranged between the first blocking portion and the second blocking portion; when the blocking protrusion is in blocking cooperation with the first blocking portion, the locking shaft is in the unlocked position. When the blocking protrusion crosses the retaining member during the rotation of the locking shaft and is in blocking cooperation with the second blocking portion, the locking shaft is in the locked position; the retaining member is used to block the blocking protrusion when the blocking protrusion is in the locked position; the limiting protrusion is used to be in blocking cooperation with the retaining ring in the axial direction of the socket.

3. The tool locking structure according to claim 2, wherein The first blocking portion is a blocking inclined surface, and the second blocking portion is a blocking curved surface; matching inclined surfaces matching the blocking inclined surface and matching inclined surfaces matching the blocking curved surface are respectively provided on both sides of the blocking protrusion.

4. The tool locking structure according to claim 2, characterized in that, The retaining member is an elastic cylindrical pin.

5. The tool locking structure according to claim 1, characterized in that, The eccentric wheel is integrally formed with the locking shaft.

6. The tool locking structure according to claim 5, characterized in that, The eccentric wheel is cylindrical.

7. The tool locking structure according to claim 5, characterized in that, The eccentric inner side of the eccentric wheel is tangent to the outer surface of the locking shaft.

8. The tool locking structure according to claim 1, characterized in that, A tool interface is provided at the end of the locking shaft.

9. The tool locking structure according to any one of claims 2-8, characterized in that, An axial tensioning member is provided between the cutting tool and the tool holder. There is one cam tightening mechanism. The tensioning hole is a through hole. The locking shaft passes through the tensioning hole and is inserted into the socket.

10. The tool locking structure according to any one of claims 2-8, characterized in that, Two coaxially arranged tensioning holes are provided on the short taper shank of the cutting tool. The tensioning holes are blind holes. There are two cam tightening mechanisms.

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