A vertical five-axis machining center

Abstract

The application discloses a vertical five-axis machining center, and belongs to the technical field of numerical control machine tools.The machining center comprises a bed body, an AC cradle rotary table, a ram, a tool magazine, a slide and a cross beam.The bed body adopts a stepped structure with a low front end and a high rear end.The AC cradle rotary table is directly fixed and installed on the low table surface at the front end of the bed body, and only performs rotary interpolation motion around the A-axis and the C-axis.The linear motion components of the X-axis, the Y-axis and the Z-axis for driving the cutter to move are all arranged on the upper rear part of the bed body, and are spatially isolated from the machining area at the front end.The AC cradle rotary table is fixed on the front part of the bed body, and the linear motion components are centrally arranged on the upper rear part of the bed body, so that the workpiece moving inertia is greatly reduced, the dynamic response is fast, and the machining precision is high;the machining area and the motion components are effectively isolated, chip removal is smooth, the rotary table is only 730mm away from the ground, feeding and discharging are convenient, the whole machine structure is compact, and the cost is low.

Description

Technical Field

[0001] This invention belongs to the field of CNC machine tool technology, specifically relating to a vertical five-axis machining center, which is particularly suitable for efficient and high-precision machining of complex curved surface parts. Background Technology

[0002] Vertical five-axis machining centers are core equipment for machining complex curved surface parts and are widely used in high-end manufacturing fields such as aerospace, automotive molds, and medical devices. Currently, most existing vertical five-axis machine tools adopt the main structure of "AC cradle rotary table + vertical spindle". In this traditional structure, the AC cradle rotary table is generally set on the X-axis slide, and moves left and right with the worktable to form the X-axis. The saddle drives the worktable to move back and forth to form the Y-axis, and the spindle moves up and down with the spindle head to form the Z-axis.

[0003] The aforementioned traditional vertical five-axis machine tool has the following technical defects in practical applications: First, the workpiece has a large moment of inertia, limiting its dynamic response performance. Because the AC cradle turntable is mounted on the X-axis slide, the workpiece not only performs rotary interpolation motion along the A and C axes with the AC turntable, but also linear interpolation motion along the X and Y axes. The overall mass of the workpiece, turntable, and slide assembly is large, resulting in a high moment of inertia and limited acceleration / deceleration performance, directly affecting machining accuracy and surface quality. This is especially true under high feed rate machining conditions, where the following error increases significantly.

[0004] Secondly, the mixing of the machining area and moving parts makes chip removal difficult, affecting equipment lifespan. In traditional structures, precision moving parts such as X and Y axis linear guides and lead screws are located near or below the worktable. Chips and cutting fluid generated during machining easily splash and penetrate the guide and lead screw areas, accelerating wear on moving parts and affecting machine tool accuracy and lifespan. Simultaneously, chips accumulate in the machining area, making them difficult to remove, requiring operators to frequently stop the machine for cleaning, reducing machining efficiency.

[0005] Third, the human-machine interaction is not convenient enough. In the traditional structure, the AC cradle turntable is set on the X-axis slide plate and moves with the X-axis. The loading and unloading positions are not fixed. The operator needs to adjust the operating position according to the position of the turntable. Moreover, the turntable is far away from the operator, making it inconvenient to clamp the workpiece, resulting in high labor intensity and long auxiliary time.

[0006] While existing patents related to vertical five-axis machining centers have made improvements from different perspectives, they still share the following common shortcomings: Firstly, the problem of kinetic inertia has not yet been systematically solved. Although some patented dual direct-drive cradle rotary table five-axis vertical machining devices (CN202323193753.2) fix the AC cradle rotary table to the machine bed, the spatial layout of its linear axis moving parts such as the crossbeam and slide and the rotary table is still not reasonable enough. The separation between linear axis motion and rotary table motion is not thorough enough. The workpiece still needs to bear part of the inertia caused by linear axis motion during the machining process, and there is still room for improvement in dynamic response performance.

[0007] Secondly, the machining area and moving parts are not effectively isolated. For example, in a high-rigidity five-axis machining center (CN202020333948.X), precision moving parts such as linear axis guideways and lead screws are mostly located near or above the machining area. Under the influence of gravity and splashing, iron filings and cutting fluid can easily penetrate into the guideway and lead screw area, accelerating the wear of moving parts and affecting the machine tool's accuracy retention and service life.

[0008] Third, the human-machine interaction is not convenient enough. For example, in a high-rigidity five-axis machining center (CN202020333948.X), the cradle turntable is located in the middle of the machine tool, which is far from the operator's position. None of the above solutions systematically optimize the turntable position from an ergonomic perspective, which is not conducive to reducing labor intensity and improving loading and unloading efficiency.

[0009] In summary, existing vertical five-axis machining center technology still has significant shortcomings in reducing workpiece inertia, achieving spatial isolation between the machining area and moving parts, and improving the convenience of human-machine interaction. There is an urgent need for a new vertical five-axis machining center structural solution that can comprehensively solve the above problems. Summary of the Invention

[0010] Purpose of the invention: To solve the above problems, the present invention provides a vertical five-axis machining center, which aims to reduce the moment of inertia of workpiece movement, improve dynamic response accuracy, and at the same time realize the isolation between the machining area and moving parts, and optimize chip removal and human-machine interaction performance.

[0011] Technical solution: This invention discloses a vertical five-axis machining center, including a bed, an AC cradle turntable, a slide, a slide seat, and a crossbeam, characterized in that: the bed adopts a stepped structure with a lower front and a higher rear; The AC cradle turntable is directly and fixedly installed on the low platform at the front end of the bed, and only performs rotary interpolation motion around the A-axis and C-axis; The X-axis, Y-axis and Z-axis linear motion components used to drive the tool movement are all located on the upper part of the machine back and are spatially isolated from the front machining area; The crossbeam slides back and forth along the Y-axis guide rail located above the back of the bed to form the Y-axis, the slide block slides left and right along the X-axis guide rail located on the crossbeam to form the X-axis, and the ram slides up and down along the Z-axis guide rail located on the slide block to form the Z-axis.

[0012] Furthermore, the table surface of the AC cradle turntable is 730mm above the ground; the front part of the bed and the surrounding area below the AC cradle turntable are provided with a guide slope with a slope angle of 40°, and a chip discharge port for discharging iron filings is provided at the center.

[0013] Furthermore, two 45mm roller linear guides with a span of 1075mm are symmetrically arranged on the upper rear of the bed, and the crossbeam is mounted on the guides; the crossbeam has a cross-sectional shape that is narrow at the top and wide at the bottom, and is driven by a single lead screw transmission system located in the center of the two guides.

[0014] Furthermore, a 45mm roller linear guide rail is provided on each of the upper and lower front sides of the crossbeam in a stepped manner, and the slide is mounted on the stepped guide rail; the slide is designed with a structure that is wider at the top and narrower at the bottom, in order to reduce the moment of inertia while ensuring support rigidity.

[0015] Furthermore, the top of the slide has a chamfered structure, and the interior of the slide is hollowed out, with the outer side supported and connected by reinforcing ribs; an electric spindle is installed at the bottom of the slide.

[0016] Furthermore, both the AC cradle turntable and the electric spindle are driven by direct drive motors; the direct drive motors are equipped with a water-cooled circulating cooling device and a temperature monitoring device.

[0017] Furthermore, a tool magazine mounting platform is provided on the left side of the bed, on which a disc-type tool magazine is fixed; the tool magazine is equipped with 24 tools as standard, and is equipped with an automatic protective door and an automatic tool changing mechanism.

[0018] Beneficial effects: Compared with the prior art, the present invention has the following advantages: 1. The moment of inertia of the workpiece is significantly reduced, and the dynamic response performance is significantly improved.

[0019] This invention directly fixes the AC cradle turntable to the low platform at the front end of the machine bed. The turntable only performs rotary interpolation motion around the A and C axes, without needing to perform linear interpolation motion along the X and Y axes. The workpiece's mass is completely decoupled from the mass of the linear axis moving parts, resulting in a much lower moment of inertia than in traditional designs where the turntable moves with the X-axis slide. Simultaneously, the crossbeam uses a single-screw drive instead of the overhead crane-style double-screw structure, significantly reducing the overall size and weight of the crossbeam compared to the double-screw drive structure, further lowering the moment of inertia. The combined application of these technologies enables the machine tool to achieve extremely fast dynamic response speed and excellent following performance, maintaining high precision even under high feed rate machining conditions, making it particularly suitable for the efficient and precise machining of complex curved surface parts.

[0020] 2. Spatial isolation between the processing area and moving parts is beneficial for maintaining precision and environmental protection.

[0021] This invention centrally positions all X, Y, and Z linear axis motion components on the upper rear of the machine bed, while the machining area is located on the lower platform at the front of the bed, completely isolating the two areas spatially. The precision linear guides, lead screws, and other moving parts are elevated above the machining area. Metal chips and cutting fluid generated during machining fall naturally under gravity, preventing splashing onto the guides and lead screws, effectively avoiding wear and contamination of the moving parts, extending the service life of the precision components, and ensuring the long-term stability of the machine tool's accuracy. Simultaneously, the machining area remains clean, eliminating the need for frequent machine shutdowns for cleaning, thus meeting the requirements of green manufacturing and clean production.

[0022] 3. Excellent ergonomic design, convenient and efficient loading and unloading.

[0023] This invention places the AC cradle turntable on a low platform at the front of the machine bed, with the turntable surface only 730mm above the ground. This height design fully considers ergonomic factors, allowing operators to easily clamp and unclamp workpieces without bending over or using auxiliary tools, significantly reducing labor intensity. Simultaneously, the turntable's location at the very front of the machine bed, very close to the operator's position, provides a wide field of vision, and the operating space is not obstructed by the machine bed structure (such as walls or columns), making loading and unloading operations extremely convenient. This user-friendly design reduces operator labor intensity while effectively shortening auxiliary time and improving overall processing efficiency.

[0024] 4. The machine has a compact structure and high cost performance.

[0025] The crossbeam of this invention is driven by a single lead screw transmission system, unlike the double lead screw transmission structure of an overhead crane. By eliminating a set of lead screw transmission components and corresponding drive motors, couplings, and other parts, the overall manufacturing cost is significantly reduced. Furthermore, the overall size and weight of the crossbeam are much lower than those of the overhead crane structure, thereby reducing the moment of inertia and improving dynamic response performance. Simultaneously, this invention compactly arranges the X, Y, and Z linear axis motion components in the upper part of the machine back, resulting in a small footprint and high space utilization, making it particularly suitable for processing workshops with strict space requirements.

[0026] 5. The transmission system has high precision and good thermal stability.

[0027] The AC cradle turntable and electric spindle in this invention are both directly driven by direct-drive motors, eliminating the need for intermediate transmission components (such as gears, worm gears, belts, etc.), achieving zero-backlash transmission, zero reverse backlash, high rotational accuracy, and fast dynamic response. The turntable body castings are all made of ductile iron, which has high tensile strength and a stable coefficient of thermal expansion, minimizing the impact of thermal deformation on machining accuracy. The direct-drive motor is equipped with a water-cooled circulating cooling device, which promptly removes the heat generated by the motor during machining, effectively suppressing motor temperature rise and heat conduction to the turntable body and spindle box. Furthermore, the direct-drive motor is equipped with a temperature monitoring device that monitors the motor's operating temperature in real time. An alarm is triggered when the temperature exceeds a set threshold to prevent overload and sintering of the direct-drive motor, ensuring the long-term reliability and accuracy maintenance of the transmission system. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the main structure of the present invention; Figure 3 This is a side view of the structure of the present invention; Figure 4 This is a top view of the structure of the present invention. Detailed Implementation

[0029] The present invention will be further described below with reference to specific embodiments and accompanying drawings. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. It should also be understood that the terminology used in the embodiments of the present invention is for describing specific specific implementation schemes and not for limiting the scope of protection of the present invention.

[0030] like Figure 1-3 As shown, the present invention provides a vertical five-axis machining center, including a bed 1, an AC cradle turntable 2, a slide 3, a tool magazine 4, a slide 5, and a crossbeam 6.

[0031] In this embodiment, the bed 1 is the basic support component of the machine tool, made of an integral casting, and bears most of the weight of the machine tool. The bed 1 adopts a stepped structure with a lower front and higher rear, placing the AC cradle turntable 2 at the lower front. This lowers the center of gravity of the AC cradle turntable 2 and makes the turntable surface only 730mm above the ground, which is a low distance that facilitates workpiece clamping, saves manpower, and is close to the operator for easy loading and unloading.

[0032] The machine bed 1 has a mounting platform on each of its left and right front sides, and the AC cradle turntable 2 is directly fixed to the platform. The upper rear of the machine bed 1 has X, Y, and Z axis moving parts. These parts all move on the upper part of the machine bed and are completely isolated from the AC cradle turntable 2 at the front end, which facilitates the falling of iron filings and keeps the processing area clean.

[0033] The front part of the bed 1 and the lower center of the AC cradle turntable 2 are all equipped with guide slopes with a 40° angle, and a chip discharge port 7 is provided in the middle to facilitate the automatic discharge of iron chips. An automatic chip conveyor can be installed below the chip discharge port 7 to automatically discharge iron chips.

[0034] A tool magazine mounting platform is located on the left side of the bed 1 for fixing the tool magazine 4. A Y-axis linear encoder mounting position is also reserved on the bed 1 for easy full closed-loop precision control.

[0035] In this embodiment, the AC cradle turntable 2 is fixedly installed on the low platform in front of the bed 1. The A-axis rotation axis is parallel to the X-axis, and the A-axis can rotate ±120°. The C-axis axis is parallel to the Z-axis, and the C-axis can rotate 360°. In this design, the AC cradle turntable 2 only performs rotational interpolation motion around the A-axis and C-axis, and does not perform any linear axis interpolation motion.

[0036] The AC cradle turntable 2 is directly driven by a direct-drive motor, featuring zero backlash, high precision, and fast rotation speed. The main body castings of the AC cradle turntable 2 are all made of ductile iron, which has high tensile strength, reducing the impact of thermal deformation on machining accuracy. The direct-drive motor uses a water-cooled circulating cooling system to promptly remove heat and reduce thermal deformation; the direct-drive motor is also equipped with a temperature monitoring device to monitor the motor temperature at any time, preventing overload and sintering of the direct-drive motor.

[0037] In this embodiment, the crossbeam 6 is located above the rear of the bed 1. Two 45mm roller linear guides are symmetrically arranged on the upper rear of the bed 1, with a span of 1075mm between them, providing strong support and load-bearing capacity. The crossbeam 6 moves back and forth along these linear guides to form a Y-axis.

[0038] A Y-axis transmission system is located in the center between the two guide rails at the rear upper part of the bed 1. It uses a single lead screw to drive the crossbeam 6 to move back and forth. Unlike the double lead screw setup of the overhead crane, the single lead screw transmission reduces costs. In addition, the overall shape and weight of the crossbeam are much lower than those of the overhead crane structure, resulting in low moment of inertia and good dynamic response.

[0039] The crossbeam 6 adopts a cross-sectional shape that is narrower at the top and wider at the bottom. This reduces the weight of the crossbeam itself and increases the support distance of the guide rail surface, thereby obtaining a greater load-bearing torque.

[0040] In this embodiment, the slide 5 is located in front of the crossbeam 6 and is mounted on the X-axis guide rail, moving left and right to form the X-axis. A 45° roller linear guide rail is provided on each of the upper and lower sides in front of the crossbeam 6, and the two guide rails are arranged in a stepped manner to increase the load-bearing torque of the X-axis guide rail. An X-axis transmission system is provided between the two guide rails to drive the slide 5 to move left and right. A mounting position for an X-axis grating ruler is also reserved in the middle of the crossbeam 6, facilitating the installation of the grating ruler and benefiting machine tool precision control.

[0041] The slide block 5 is designed with a shape that is wider at the top and narrower at the bottom, which reduces the sliding block's moment of inertia while ensuring the rigidity of the slide block's support.

[0042] In this embodiment, the slide block 3 is installed in front of the slide block 5. Two 45mm roller linear guide rails are provided in front of the slide block 5. The slide block 3 moves up and down on these guide rails to form the Z-axis.

[0043] The top of the slide 3 has a chamfered structure to reduce weight, and the interior of the slide is hollowed out, with reinforcing ribs supporting the outer side to ensure its rigidity. The spindle is located at the bottom of the slide 3; in this embodiment, an electric spindle is standard. Compared to belt drives, electric spindles offer higher speeds, zero friction, zero backlash, and higher transmission efficiency, improving machining accuracy and efficiency. The electric spindle is also driven by a direct-drive motor and equipped with a water-cooled circulating cooling system.

[0044] In this embodiment, the tool magazine 4 is installed on the tool magazine mounting platform on the left side of the bed 1. It adopts a 24-disc cam-type tool magazine, with an optional 30-disc magazine. The tool magazine 4 is equipped with an automatic protective door. When tool exchange is required, the electric spindle moves to the same side with the slide ram 3, and the tool exchange mechanism realizes automatic tool changing, thereby improving machining efficiency.

[0045] In the vertical five-axis machining center of this invention, the workpiece is clamped on the AC cradle turntable 2 during machining. The turntable 2 only performs rotary interpolation movements along the A and C axes. The crossbeam 6 moves back and forth along the Y-axis guide rail, the slide 5 moves left and right along the X-axis guide rail, and the ram 3 moves up and down along the Z-axis guide rail, together driving the tool on the electric spindle to move in three-dimensional space, realizing five-axis linkage machining of the workpiece.

[0046] The iron filings generated during processing are collected through a 40° inclined guide surface to the chip discharge port directly below the turntable, and then discharged by an automatic chip conveyor.

[0047] The present invention has been described in detail above with reference to the accompanying drawings and embodiments. Those skilled in the art can make various modifications to the present invention based on the above description. Therefore, certain details in the embodiments should not be construed as limiting the present invention, and the scope of protection of the present invention shall be defined by the appended claims.

Claims

1. A vertical five-axis machining center, comprising a bed (1), an AC cradle rotary table (2), a slide (3), a tool magazine (4), a slide block (5), and a crossbeam (6), characterized in that: The bed (1) adopts a stepped structure with a lower front and a higher back; The AC cradle turntable (2) is directly fixedly installed on the low platform at the front end of the bed (1), and only performs rotary interpolation motion around the A-axis and C-axis; The X-axis, Y-axis and Z-axis linear motion components used to drive the tool movement are all located at the upper rear part of the bed (1) and are spatially isolated from the front machining area; The crossbeam (6) slides back and forth along the Y-axis guide rail located above the bed to form the Y-axis. The slide block (5) slides left and right along the X-axis guide rail located on the crossbeam (6) to form the X-axis. The slide block (3) slides up and down along the Z-axis guide rail located on the slide block (5) to form the Z-axis.

2. The vertical five-axis machining center according to claim 1, characterized in that: The table surface of the AC cradle turntable (2) is 730mm above the ground; the front of the bed (1) and the surrounding area below the AC cradle turntable (2) are provided with a guide slope with a slope angle of 40°, and a chip discharge port (7) for discharging iron filings is provided at the center.

3. The vertical five-axis machining center according to claim 1, characterized in that: The upper rear part of the bed (1) is symmetrically arranged with two 45 roller linear guides with a span of 1075mm. The crossbeam (6) is installed on the guides. The crossbeam (6) has a cross-sectional shape that is narrow at the top and wide at the bottom, and is driven by a single screw drive system located in the center of the two guides.

4. The vertical five-axis machining center according to claim 1, characterized in that: The front of the crossbeam (6) is provided with a 45 roller linear guide rail on each of the upper and lower sides in a stepped shape, and the slide (5) is installed on the stepped guide rail; the slide (5) is designed with a structure that is wider at the top and narrower at the bottom, in order to reduce the moment of inertia while ensuring the rigidity of the support.

5. The vertical five-axis machining center according to claim 1, characterized in that: The top of the slide (3) is provided with a chamfered structure, and the interior of the slide is hollowed out. The outside is supported and connected by reinforcing ribs. An electric spindle is installed at the bottom of the slide (3).

6. The vertical five-axis machining center according to claim 1, characterized in that: The AC cradle turntable (2) and the electric spindle are both driven by direct drive motors; the direct drive motors are equipped with water-cooled circulating cooling devices and temperature monitoring devices.

7. The vertical five-axis machining center according to claim 1, characterized in that: The left side of the bed (1) is provided with a tool magazine installation platform, on which a disc-type tool magazine (4) is fixed; the tool magazine (4) is equipped with 24 tools as standard, and is provided with an automatic protective door and an automatic tool changing mechanism.

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