A mechanism for connecting a tool holder and an input shaft of a machine tool angle head in two parts

Abstract

The utility model relates to a kind of mechanism that machine tool angle head tool shank and input shaft are connected in two parts, including tool shank body, the tool shank body one end is used to connect with machine tool spindle, the tool shank body bottom is equipped with output shaft, the power transmission between the tool shank body and output shaft is through internal hexagonal structure, angle head body is installed on the output shaft surface, tool shank is connected with machine tool spindle, receives the power transmission of machine tool, power is transmitted by the internal hexagonal structure between tool shank and output shaft, so that output shaft obtains rotary power, tool shank and output shaft are realized centring cooperation by 7:24 conic surface, ensure that both are accurately aligned in radial direction, simultaneously, using 12.9 level's M12 screw is locked and connected, under the tensioning effect of screw, tool shank and output shaft realize double-sided lamination, not only further ensure the accuracy of positioning, also enhanced the rigidity of connection, provide reliable guarantee for the stable transmission of power and the overall stable operation of mechanism.

Description

Technical Field

[0001] This utility model relates to the field of machining technology, specifically a mechanism for separately connecting the angle head tool holder and the input shaft of a machine tool. Background Technology

[0002] Improving the processing capabilities and precision of machine tools has always been key to the industry's development. As an important accessory for machine tools, the angle head enables the tool rotation center line to form a specific angle with the spindle rotation center line to process workpieces, greatly expanding the processing range of machine tools and playing an indispensable role in the processing of complex parts.

[0003] Traditional machine tool angle head tool holder and output shaft connection methods have many drawbacks. Early methods often used an integral connection, which meant that if any part was damaged, the entire angle head assembly often needed to be replaced, resulting in high repair costs and time-consuming labor. Later, some separate connection methods were developed, but they performed poorly in terms of positioning accuracy and connection rigidity. For example, some common methods using simple key connections or ordinary conical surface centering cannot achieve precise center positioning when facing high-speed, high-precision machining requirements. This can easily lead to angle head wobbling during machining, resulting in increased machining errors and seriously affecting machining accuracy. Such methods cannot meet the extremely high precision requirements of industries such as aerospace and precision mold manufacturing.

[0004] Furthermore, traditional angle head systems lack flexibility. Different machine tool spindle models have different interface specifications and dimensions, meaning that an angle head can typically only be used with one specific machine tool spindle model. If a factory has multiple machine tool models, it needs to equip each machine tool with a different angle head, which undoubtedly increases equipment procurement costs and management complexity. When angle heads need to be used for machining on different machine tools, complex modifications or even repurchase of the angle heads are often required, severely restricting the improvement of production efficiency and the control of machining costs. Therefore, we need to provide a mechanism that separately connects the machine tool angle head tool holder and the input shaft. Utility Model Content

[0005] The purpose of this utility model is to provide a mechanism for the separate connection of the tool holder and the input shaft of a machine tool angle head. The tool holder body and the output shaft transmit power through an internal hexagonal structure, with an inner conical surface for centering and fitting. The tool holder and the output shaft are tightened by screws to ensure double-sided contact, resulting in high positioning accuracy and strong connection rigidity. Furthermore, the internal hexagonal drive provides high stability, thus solving the problems mentioned in the background art.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a mechanism for separately connecting a machine tool angle head tool holder and an input shaft, comprising:

[0007] The tool holder body has one end for connection to the machine tool spindle, and an output shaft at the bottom of the tool holder body. Power is transmitted between the tool holder body and the output shaft through an internal hexagonal structure. An angle head body is mounted on the surface of the output shaft, and the other end of the output shaft is connected to a transmission mechanism inside the angle head body for transmitting power to the angle head body.

[0008] Preferably, the tool holder body and the output shaft are fastened together by an internal hex screw to achieve double-sided fit.

[0009] Preferably, a rotating ring assembly is installed on the surface of the angle head body to achieve rotational adjustment of the angle head body within a certain angle range.

[0010] Preferably, one end of the output shaft is engaged with the tool holder body through a conical centering structure to achieve precise center positioning with a 7:24 conical surface.

[0011] Preferably, the rotating ring assembly is connected to the angle head body via a bearing to achieve relative rotation.

[0012] Preferably, sealing components are provided at the connection points between the tool holder body and the output shaft, the connection points between the output shaft and the angle head body, and the connection points between the rotating ring assembly and the angle head body.

[0013] Preferably, the internal hex screw is an M12 screw of grade 12.9.

[0014] Compared with the prior art, the beneficial effects of this utility model are:

[0015] This utility model combines an inner conical surface centering fit with screw tightening, allowing the tool holder and output shaft to achieve a tight fit on both sides, significantly improving positioning accuracy, reducing positional deviations during machining, and ensuring precise machining dimensions. At the same time, this structure significantly enhances connection rigidity, enabling it to withstand greater cutting forces, avoiding vibration during high-speed operation, and ensuring machining stability. The internal hexagonal drive structure transmits power directly and efficiently, reducing power loss and allowing the angle head to operate stably under high load conditions. The split design facilitates individual component replacement and maintenance, reducing maintenance costs. It can also be adapted to various machine tools by changing different tool holders, improving equipment versatility and efficiency. Attached Figure Description

[0016] Figure 1 This is a front view of the structure of this utility model;

[0017] Figure 2 This is a three-dimensional structural view of the present invention;

[0018] Figure 3 This is an exploded perspective view of the structure of this utility model;

[0019] Figure 4This is an exploded cross-sectional view of the structure of this utility model;

[0020] Figure 5 This is a cross-sectional view of the structure of this utility model.

[0021] In the diagram: 1. Tool holder body; 2. Output shaft; 3. Hexagonal socket structure; 4. Angle head body; 5. Hexagonal socket screw; 6. Rotary ring assembly. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0023] Please see Figure 1-5 This utility model provides a technical solution: a mechanism for separately connecting the angle head tool holder and the input shaft of a machine tool, comprising:

[0024] The tool holder body 1 has one end for connecting to the machine tool spindle. The bottom of the tool holder body 1 is provided with an output shaft 2. The tool holder body 1 and the output shaft 2 transmit power through an internal hexagonal structure 3. An angle head body 4 is mounted on the surface of the output shaft 2. The other end of the output shaft 2 is connected to the transmission mechanism inside the angle head body 4 for transmitting power to the angle head body 4.

[0025] Specifically, the tool holder body 1 and the output shaft 2 transmit power through an internal hexagonal structure 3, with an inner conical surface for centering. Tightening with screws ensures a double-sided fit between the tool holder and the output shaft 2, resulting in high positioning accuracy and strong connection rigidity. The internal hexagonal drive further enhances stability. The combination of the inner conical surface centering and screw tightening allows for a tight double-sided fit between the tool holder and the output shaft 2, significantly improving positioning accuracy, reducing positional deviations during machining, and ensuring precise machining dimensions. Simultaneously, this structure significantly strengthens connection rigidity, enabling it to withstand greater cutting forces, preventing vibrations during high-speed operation, and ensuring machining stability. The internal hexagonal drive structure transmits power directly and efficiently, reducing power loss and allowing the angle head to operate stably even under high load conditions. The modular design facilitates individual component replacement and maintenance, reducing maintenance costs. Furthermore, by changing different tool holders, it can be adapted to various machine tools, improving equipment versatility and efficiency.

[0026] The tool holder body 1 and the output shaft 2 are fastened together by an internal hex screw 5 to achieve double-sided fit;

[0027] Furthermore, the internal hexagon screw 5 is made of 40CrNiMoA alloy steel, and after quenching and tempering, its hardness reaches HRC33-38, and its thread accuracy is 6g. The screw head and the countersunk hole of the tool holder body 1 adopt an H7 / h6 transition fit. During assembly, the tightening torque of the screw is controlled at 35-40 N·m. The axial tension of the screw makes the contact pressure between the contact surface of the tool holder body 1 and the output shaft 2 reach 80-100 MPa, thereby eliminating the gap between the contact surfaces, improving the connection rigidity, and avoiding the impact of vibration caused by the gap during high-speed cutting on the machining accuracy.

[0028] The hexagonal hole and hexagonal shaft of the internal hexagonal structure 3 adopt an H7 / f6 clearance fit. The tolerance of the opposite side dimension of the hexagon is ±0.01mm, and the rounding radius of the hexagonal edge is 0.2-0.5mm. During power transmission, the side of the hexagonal shaft is in close contact with the side of the hexagonal hole, and the torque is transmitted through surface contact. Compared with key connection, the contact area is increased by more than 30%, which can reduce the stress per unit area, reduce wear, and improve the power transmission efficiency to more than 95%. This solves the problems of stress concentration and limited torque transmission that are common in traditional key connections.

[0029] A rotating ring assembly 6 is installed on the surface of the angle head body 4 to realize the rotation adjustment of the angle head body 4 within a certain angle range;

[0030] It should be noted that the rotating ring assembly 6 includes a rotating ring body, a wear-resistant bushing, and a thrust bearing. The rotating ring body is made of QT600-3 ductile iron, and the wear-resistant bushing is made of tin bronze ZCuSn10Pb1. They are press-fitted into the inner hole of the rotating ring body through an interference fit. The rotating ring body and the angle head body 4 are connected by a thrust bearing, which is a single-row tapered roller bearing. Its outer ring is interference-fitted with the bearing seat of the angle head body 4, and its inner ring is transition-fitted with the journal of the rotating ring body. When the angle needs to be adjusted, the rotating ring body is rotated, and the wear-resistant bushing slides into contact with the outer circle of the angle head body 4. The thrust bearing bears the axial force of the rotating ring body, making the rotation adjustment process smooth and effortless. At the same time, the wear-resistant bushing can reduce the wear between the rotating ring body and the angle head body 4, improve the service life of the rotating ring assembly 6, and solve the problems of easy jamming and rapid wear of traditional rotating adjustment structures.

[0031] One end of the output shaft 2 is engaged with the tool holder body 1 through a conical centering structure, achieving precise center positioning with a 7:24 conical surface;

[0032] It is worth noting that the surface roughness of the 7:24 conical centering structure is Ra0.4μm, the surface contact rate is not less than 80%, the diameter tolerance of the large end of the conical surface is H8, and the diameter tolerance of the small end is h8. During assembly, the conical surface of the tool holder body 1 and the conical surface of the output shaft 2 are tightly fitted by axial force. By utilizing the self-centering characteristic of the conical surface, the coaxiality of the two is controlled within 0.005mm, ensuring the concentricity during power transmission, avoiding vibration and noise caused by excessive coaxiality error, and improving the stability of the mechanism operation. At the same time, the conical surface fit can also withstand a certain axial force, share the load of the internal hexagon screw 5, and extend the service life of the screw.

[0033] The tool holder body 1 is made of 45CrNiMoV alloy steel, and after overall quenching, the surface hardness reaches HRC45-50, and the core hardness is HRC28-32, exhibiting high strength and toughness. The output shaft 2 is made of 20CrMnTi carburized steel, with a carburized layer depth of 0.8-1.2mm, a surface hardness of HRC58-62, and a core hardness of HRC30-35, possessing excellent wear resistance and fatigue resistance. The material combination of the tool holder body 1 and the output shaft 2 allows them to complement each other in power transmission and load bearing. The tool holder body 1 can withstand large impact loads, while the output shaft 2 can resist long-term wear, improving the service life and operational reliability of the entire mechanism.

[0034] The rotating ring assembly 6 is connected to the angle head body 4 via bearings to achieve relative rotation.

[0035] Sealing components are provided at the connection points of the tool holder body 1 and the output shaft 2, the connection points of the output shaft 2 and the angle head body 4, and the connection points of the rotating ring assembly 6 and the angle head body 4;

[0036] The sealing components include a skeleton oil seal and an O-ring. The skeleton oil seal is made of nitrile rubber and is installed on the outer side of the mating surface between the tool holder body 1 and the output shaft 2. Its lip is interference-fitted with the outer circle of the output shaft 2, with an interference amount of 0.1-0.2mm, to prevent cutting fluid and dust from entering the connection part radially. The O-ring is made of fluororubber with a cross-sectional diameter of 3-5mm and is installed in the sealing grooves of the connecting flange face between the output shaft 2 and the angle head body 4, and the connecting flange face between the rotating ring assembly 6 and the angle head body 4. The depth of the sealing groove is 0.2-0.3mm smaller than the cross-sectional diameter of the O-ring. After assembly, the O-ring is compressed to achieve axial sealing. Through the synergistic effect of the skeleton oil seal and the O-ring, cutting fluid, oil, and dust can be effectively prevented from entering the mechanism, avoiding corrosion and wear of internal parts, solving the problem of mechanism failure caused by poor sealing, and improving the reliability of the mechanism.

[0037] The socket head cap screw 5 is set to a 12.9 grade M12 screw;

[0038] Grade 12.9 is a common grade for high-strength screws. Its tensile strength and yield strength are far higher than those of ordinary grade screws, providing strong axial tensile force. This effectively tightens the tool holder and output shaft 2, ensuring a tight double-sided fit and significantly improving connection rigidity. This allows the screw to better withstand cutting forces during machining, reducing vibration caused by loose connections and ensuring machining stability. The M12 thread specification matches the connection structure of the angle head tool holder and output shaft 2, enabling precise locking. Combined with the 7:24 conical centering structure, positioning accuracy is further enhanced, ensuring precise radial alignment of the tool holder and output shaft 2, reducing positional deviations during machining, and guaranteeing dimensional accuracy.

[0039] This device connects the tool holder to the machine tool spindle, receiving power from the machine tool. This power is transmitted through the internal hexagonal structure 3 between the tool holder and the output shaft 2, enabling the output shaft 2 to rotate. The tool holder and output shaft 2 are centered via a 7:24 taper, ensuring precise alignment in the radial direction. Simultaneously, a 12.9 grade M12 screw is used for locking the connection. Under the tension of the screw, the tool holder and output shaft 2 achieve double-sided contact, further ensuring positioning accuracy and enhancing connection rigidity. This provides a reliable guarantee for stable power transmission and overall stable operation of the mechanism. The output shaft 2 transmits the received power to the transmission mechanism inside the angle head body 4, driving the angle head body 4 to operate. The rotating ring assembly 6 is mounted on the angle head body 4, allowing the angle head body 4 to rotate and adjust within a certain range to adapt to different machining requirements. Through this coordination and power transmission, the entire mechanism achieves flexible application and stable machining on different machine tool spindles.

[0040] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A mechanism for separately connecting the angle head tool holder and the input shaft of a machine tool, characterized in that, include: The tool holder body (1) has one end for connecting to the machine tool spindle. The bottom of the tool holder body (1) is provided with an output shaft (2). The tool holder body (1) and the output shaft (2) transmit power through an internal hexagonal structure (3). An angle head body (4) is mounted on the surface of the output shaft (2). The other end of the output shaft (2) is connected to the transmission mechanism inside the angle head body (4) to transmit power to the angle head body (4).

2. The mechanism for separately connecting the machine tool angle head tool holder and the input shaft according to claim 1, characterized in that: The tool holder body (1) and the output shaft (2) are fastened together by an internal hex screw (5) to achieve double-sided fit.

3. The mechanism for separately connecting the machine tool angle head tool holder and the input shaft according to claim 2, characterized in that: The angle head body (4) is equipped with a rotating ring assembly (6) to achieve rotational adjustment of the angle head body (4) within a certain angle range.

4. The mechanism for separately connecting the machine tool angle head tool holder and the input shaft according to claim 3, characterized in that: One end of the output shaft (2) is engaged with the tool holder body (1) through a conical centering structure, achieving precise center positioning with a 7:24 conical surface.

5. The mechanism for separately connecting the machine tool angle head tool holder and the input shaft according to claim 3, characterized in that: The rotating ring assembly (6) and the angle head body (4) are connected by bearings to achieve relative rotation.

6. The mechanism for separately connecting the machine tool angle head tool holder and the input shaft according to claim 1, characterized in that: Sealing components are provided at the connection points of the tool holder body (1) and the output shaft (2), the connection points of the output shaft (2) and the angle head body (4), and the connection points of the rotating ring assembly (6) and the angle head body (4).

7. The mechanism for separately connecting the machine tool angle head tool holder and the input shaft according to claim 2, characterized in that: The internal hex screw (5) is set to an M12 screw of grade 12.9.

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