All-attitude five-axis turning and milling combined machine tool matched with non-orthogonal main shaft

Abstract

The invention discloses an all-attitude five-axis turning and milling combined machine tool matched with a non-orthogonal main shaft, and belongs to the technical field of high-end numerical control machine tools. According to the technical scheme, the turning and milling machine comprises a machine body and a turning and milling workbench arranged on the machine body, and a sliding seat is movably arranged on the machine body; the X-axis transmission system is arranged on the lathe bed, is in driving connection with the sliding seat and is used for driving the sliding seat to move in the X-axis direction; the Z-axis transmission system is arranged on the sliding seat; the spindle box is in driving connection with the Z-axis transmission system and used for moving in the Z-axis direction. And the turning and milling main shaft is rotatably connected to the main shaft box. The invention has the following beneficial effects: through the combined design of a series of technical characteristics of the 45-degree non-orthogonal main shaft and the-30-180-degree all-attitude adjusting structure thereof, the long-standing technical problems of limited machining range, insufficient angle adjusting precision, low multi-process circulation efficiency and the like of the traditional orthogonal main shaft machine tool are solved; and the machining flexibility, the positioning precision, the whole machine rigidity and the process adaptability are all substantially improved.

Description

A five-axis turning and milling composite machine tool with a non-orthogonal spindle for all postures Technical Field

[0001] This invention belongs to the field of high-end CNC machine tool technology and relates to a full-attitude five-axis turning and milling composite machining equipment equipped with a 45° non-orthogonal spindle. The spindle can achieve multi-angle precise positioning within a range of -30° to 180°, and is suitable for integrated machining of complex irregular parts in aerospace, energy equipment, precision grinding tools and other fields. It can complete multiple processes such as turning, milling, drilling and boring in a single clamping. Background Technology

[0002] Five-axis milling and turning machine tools are strategic equipment in modern high-end manufacturing. By integrating multiple machining processes such as turning, milling, drilling, and boring onto a single platform, they can complete multi-process machining of complex parts in a single setup. They are widely used in the manufacturing of key components such as aerospace engine impellers / blades, large gearboxes for energy equipment, and precision mold cavities. As the requirements for geometric complexity, surface integrity, and machining efficiency of parts continue to increase in high-end equipment, the ability of the machine tool spindle to adjust its spatial orientation has become a core bottleneck restricting the machining range and process flexibility. Currently, most commercially available five-axis milling and turning machine tools use fixed orthogonal spindle layouts or only have limited vertical / horizontal switching capabilities, making it difficult to adapt to interference-free machining of irregular features such as deep cavities, undercuts, and oblique holes.

[0003] Five-axis milling and turning composite machine tools are core equipment in the high-end manufacturing field, but existing technologies have obvious limitations: 1. Traditional machine tool spindles are mostly fixed in angle or can only switch between vertical and horizontal modes, which cannot adapt to the multi-directional machining needs of complex irregular parts and are prone to problems such as tool interference and machining blind spots; 2. Some adjustable spindles are also mostly orthogonal structures, with limited angle adjustment range, and poor adaptability to machining parts with irregular curved surfaces, deep cavities, and oblique features; 3. Multi-process and multi-directional machining requires frequent workpiece clamping or equipment changes, which not only reduces production efficiency but also easily introduces repeatability errors, making it difficult to meet the requirements of high-end manufacturing for machining accuracy and process flexibility.

[0004] In summary, while existing five-axis milling and turning machine tools have achieved multi-axis linkage, their spindle layout remains confined to an orthogonal coordinate system—that is, the spindle axis is always perpendicular to a certain guideway direction or can only oscillate within a limited orthogonal plane. This architecture forces the machine tool to rely on a large range of table rotation or long tool overhang to compensate when facing non-orthogonal features or spatially irregular curved surfaces, thus sacrificing rigidity, accuracy, and dynamic response performance. Particularly for aerospace / energy components with features such as inclined oil passages, spatially curved flow channels, and irregularly shaped deep cavities, orthogonal spindle machine tools often require the design of dedicated angle head fixtures or the use of inefficient processes such as electrical discharge machining (EDM) to supplement machining, severely hindering the widespread application of efficient and precision manufacturing processes such as "milling instead of grinding" and "turning instead of milling." Therefore, developing a new type of milling and turning machine tool that can overcome the limitations of orthogonal spindles and achieve full-attitude, blind-spot-free machining has become an urgent technical challenge in this field. Summary of the Invention

[0005] In order to solve the technical problems existing in the prior art, the present invention provides a full-attitude five-axis turning and milling composite machine tool with a 45° non-orthogonal spindle, which takes into account the processing flexibility, positioning accuracy and overall machine rigidity.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a five-axis turning-milling composite machining center with a non-orthogonal spindle, comprising a bed and a turning-milling worktable mounted on the bed, and further comprising: a slide movably mounted on the bed; an X-axis transmission system mounted on the bed and drivenly connected to the slide for driving the slide to move along the X-axis; a Z-axis transmission system mounted on the slide; a spindle box drivenly connected to the Z-axis transmission system for moving along the Z-axis; and a turning-milling spindle, the spindle axis of which forms a 45° angle with the horizontal plane, creating a 45° non-orthogonal structure, the turning-milling spindle being rotatable. The spindle is grounded and connected to the spindle box, allowing for full-attitude angle adjustment within a range of -30° to 180° around the horizontal axis; a balance cylinder, mounted on the slide and driven by the spindle box, is used to counteract its own weight during spindle angle adjustment; a spindle-milling conversion hydraulic station, mounted on the X-axis transmission system, is used to lock the spindle after angle adjustment and to switch between turning and milling modes; an encoder, mounted on the spindle, is used to provide angle positioning signals; the milling table is a rotary table that is linked with the milling spindle after full-attitude angle adjustment to achieve five-axis machining.

[0007] Furthermore, both the bed and the slide are integrally cast structures, and they are arranged symmetrically based on the 45° non-orthogonal force characteristics of the milling spindle.

[0008] Furthermore, the milling and turning table is slidably mounted on the machine bed for moving along the Y-axis, and an adjustable foot B is provided on one side of the track on the machine bed for sliding the milling and turning table.

[0009] Furthermore, a tool magazine is provided on one side of the bed, which is used to store turning tools and milling tools.

[0010] Furthermore, the X-axis transmission system is equipped with an air storage tank, which provides an air source for the pneumatic components of the equipment.

[0011] Furthermore, the bed is equipped with a spiral chip conveyor, and a composite chip conveyor is provided on one side of the bed. The spiral chip conveyor and the composite chip conveyor work together.

[0012] Furthermore, the bed is equipped with a whole machine lifting device, and several adjustable feet A are provided under the bed for adjusting the installation level.

[0013] Furthermore, the milling spindle is equipped with a first motor and a second motor. The first motor is used to drive the milling spindle to rotate around a horizontal axis to adjust the angle, and the second motor is used to drive the cutting tool of the milling spindle to rotate.

[0014] Furthermore, the encoder is a high-precision encoder, which is connected to the spindle milling conversion hydraulic station and control system to achieve a spindle angle repeatability accuracy of ±5″.

[0015] The present invention also includes a five-axis turning and milling composite machining center with a non-orthogonal spindle, comprising a bed and a slide mounted on the bed, and further comprising: a turning and milling table slidably mounted on the bed for moving along the Y-axis; an X-axis transmission system mounted on the bed and drivenly connected to the slide; a Z-axis transmission system mounted on the slide; a spindle box drivenly connected to the Z-axis transmission system; a turning and milling spindle, the spindle axis of which forms a 45° angle with the horizontal plane, rotatably connected to the spindle box, and capable of full-attitude angle adjustment around the horizontal axis within a range of -30° to 180°; the turning and milling table is linked with the turning and milling spindle to complete turning, milling, drilling, and boring operations in a single setup.

[0016] The beneficial effects of the present invention: Compared with the prior art, the five-axis turning and milling composite machining tool with non-orthogonal spindle described in the present invention has the following technical features and beneficial effects: (1) Breaking through the limitations of orthogonal spindle and realizing full-attitude blind-spot machining The present invention adopts a 45° non-orthogonal turning and milling spindle, whose axis is at a 45° angle with the horizontal plane, which is different from the traditional orthogonal spindle structure; the spindle can be rotatably connected to the spindle box, and under the drive of the first motor, it can be adjusted in all attitudes from -30° to 180° around the horizontal axis, covering horizontal, inclined, vertical and inverted machining postures; with the linkage control of the rotary turning and milling table, the tool can enter the machining area from any spatial angle, effectively solving the problem of tool interference and machining blind spots in the deep cavity sidewall, undercut features, inclined oil holes and other parts of the traditional orthogonal spindle, and is particularly suitable for one-time complete machining of complex irregular parts such as aerospace impellers / blades, energy equipment gearboxes, and precision mold cavities.

[0017] (2) High-precision and fast angle positioning improves processing efficiency and consistency. The spindle angle adjustment is driven by the first motor, and the balance cylinder is connected to the spindle box drive. During the rotation of the spindle around the horizontal axis, the weight of the spindle box is offset in real time, ensuring that the large inertia component runs smoothly and without impact within a wide adjustment range of -30° to 180°. After the angle is in place, the spindle turning and milling conversion hydraulic station performs the locking action to rigidly fix the turning and milling spindle at the target angle. The high-precision encoder provides real-time feedback of the position signal, forming a closed loop with the control system to achieve a repeatability accuracy of ±5″ and a single angle switching time of ≤5 seconds. The above structures work together to ensure the angle consistency in multi-process continuous processing and significantly shorten the non-cutting auxiliary time, making the overall processing efficiency more than 30% higher than the traditional multi-station clamping scheme.

[0018] (3) The rigidity of the whole machine is optimized to ensure the machining accuracy of all angles. The bed and slide adopt a symmetrical integral casting process, and the structural layout is optimized based on the force characteristics of the 45° non-orthogonal spindle in the process of full attitude adjustment. This design enables the cutting force to be evenly distributed to the basic components of the whole machine through the force transmission path of spindle box-Z-axis transmission system-slide-bed at any angle from -30° to 180°, avoiding local stiffness weakening or force eccentricity caused by spindle attitude change. Compared with conventional welded bed or asymmetrical layout, the present invention still has excellent anti-torsion and anti-vibration performance under extreme angle conditions (such as -30° inverted milling, 180° vertical turning), effectively suppressing tool vibration and ensuring the surface machining quality of parts.

[0019] (4) Multiple processing steps can be completed in one clamping, reducing the overall production cost. This invention uses the full attitude adjustment capability of the 45° non-orthogonal spindle and the five-axis linkage of the rotary milling table to enable the workpiece to complete all processes such as turning the outer circle, boring, milling the plane, drilling the inclined hole, and chamfering in one clamping. The tool magazine is located on one side of the bed and can store turning tools and milling cutters at the same time. The tool change time is ≤4 seconds, which can quickly adapt to the process change requirements. The above integrated design completely eliminates the multiple clamping and multiple equipment turnover caused by process flow in traditional processing. On the one hand, it avoids the introduction of repeated positioning errors. On the other hand, it enables a single equipment to replace multiple machine tool combinations with different fixed angles, significantly reducing equipment procurement costs and production site occupation, and simplifying the process flow and personnel configuration.

[0020] (5) Multi-module collaborative protection to improve equipment operation stability. This invention integrates multiple auxiliary function modules to ensure the reliability of the whole machine: the air tank is set in the X-axis transmission system to provide a stable air source for the tool magazine, pneumatic fixtures and other components; the spiral chip conveyor is embedded in the bed, and the composite chip conveyor is set on one side of the bed. The two work together to achieve rapid collection and discharge of chips under different spindle postures and angles, avoiding chip accumulation from interfering with the processing area; the whole machine lifting device is integrated on the top of the bed, and adjustable feet A and B are distributed at the bottom of the bed and the side of the guide rail, respectively undertaking the functions of overall machine leveling and local support, ensuring the installation accuracy and relocation convenience of the equipment. The above modules are structured based on the actual working conditions of the machine tool to form a complete and self-consistent functional support system. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and detailed embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein: Figure 1 is a schematic diagram of the structure of the present invention 1; Figure 2 is a schematic diagram of the structure of the present invention 2; Figure 3 is a schematic diagram of the structure of the spindle milling conversion hydraulic station of the present invention; Figure 4 is a schematic diagram of the working principle of the spindle milling conversion hydraulic station of the present invention; the reference numerals in the figures are: 1-milling spindle, 2-Z-axis transmission system, 3-spindle box, 4-X-axis transmission system, 5-air tank, 6-slide, 7-bed, 8-milling table, 9-machine lifting device, 10-adjustable foot A, 11-adjustable foot B, 12-spiral chip conveyor, 13-tool magazine, 14-balance cylinder, 15-spindle milling conversion hydraulic station, 16-compound chip conveyor, 18-bottom of oil tank, 19-wire box, 20-valve group, 21-accumulator, 22-oil tank cover, 23-air filter, 24-level gauge, 25-oil tank body. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for explaining the invention and are not intended to limit the invention. The following description, with reference to Figures 1-4, further illustrates the full-attitude five-axis turning and milling composite machine tool equipped with a non-orthogonal spindle.

[0023] Example 1 This example provides an overview of the overall solution of the present invention.

[0024] 1. Overall Mechanism Description: Spindle Full Attitude Adjustment Module: Includes direct drive spindle, C-axis angle adjustment, spindle milling conversion hydraulic station 15, and balance cylinder 14. It is the core unit for realizing full attitude angle adjustment of non-orthogonal spindle from -30° to 180°.

[0025] 2. Five-axis machining module: It consists of a 45° non-orthogonal milling spindle 1, Z-axis transmission system 2, X-axis transmission system 4, and rotary milling table 8, and is responsible for realizing multi-process, multi-directional five-axis linkage machining.

[0026] 3. Auxiliary function modules: including tool magazine 13, spiral / composite chip conveyor 12 and 16, air tank 5, to ensure stable operation of the equipment and realize the stable operation of the machine tool and the smooth realization of functions.

[0027] Basic support module: Composed of bed 7 and slide 6, it adopts an integral casting process to provide high rigidity support for the whole machine.

[0028] The control process is as follows: 1. Spindle angle adjustment process: The direct drive motor drives the 45° non-orthogonal spindle box to rotate around the horizontal axis. The balance cylinder moves synchronously to counteract the weight of the spindle box. According to the processing requirements, the spindle is adjusted to the target angle within the range of -30° to 180°. After the angle is in place, the hydraulic system works to lock the spindle at the required angle. The high-precision encoder feeds back the position signal. Only after confirming that the angle positioning accuracy meets the standard can the processing process be started.

[0029] 2. The five-axis linkage control system links and matches the spindle adjustment angle with the table rotation and linear axis movement. The motion control algorithm is optimized for the structural characteristics of the 45° non-orthogonal spindle to achieve continuous blind-spot-free machining of complex curved surfaces and irregular features.

[0030] The tool magazine enables automatic tool changing with a tool changing time of ≤4 seconds, adapting to the tool switching needs of multi-process machining; the spiral chip conveyor and the compound chip conveyor work together to ensure that iron chips are quickly discharged at different machining angles, avoiding chip accumulation that affects machining; the air tank provides a stable air source for all pneumatic components of the equipment, the adjustable feet ensure the installation level accuracy of the equipment, and the whole machine lifting device facilitates the installation, relocation and maintenance of the equipment.

[0031] The core innovations are as follows: 1. The spindle adopts a 45° non-orthogonal structure design, which is different from the traditional orthogonal spindle. It can freely adjust the machining angle around the horizontal axis within the range of -30° to 180°, covering all posture machining needs such as horizontal, inclined, and vertical. The spindle adopts hydraulic drive for switching between turning and milling functions, locking and releasing. The balance cylinder counteracts the weight of the spindle box in real time, ensuring a smooth and shock-free angle adjustment process. With a high-precision encoder, the spindle angle repeatability can reach within ±5″, and the single angle switching time is ≤5 seconds, which is suitable for efficient continuous machining.

[0032] 2. The bed and slide adopt a symmetrical integral casting process, and the structural layout is optimized by combining the force characteristics of the non-orthogonal spindle. It has excellent anti-torsion and anti-vibration performance within the full angle adjustment range of the spindle from -30° to 180°, effectively avoiding machining accuracy deviation caused by angle changes and ensuring the surface machining quality of parts.

[0033] The 45° non-orthogonal spindle's full attitude adjustment function works in conjunction with the rotary table to achieve blind-spot-free machining of complex and irregularly shaped parts. It can complete all processes such as turning, milling, drilling, boring, and chamfering in one clamping, eliminating the need for frequent tooling and equipment changes and greatly improving process adaptability.

[0034] The machine tool gains are as follows: 1. Improved machining flexibility: 45° non-orthogonal spindle with full attitude angle adjustment from -30° to 180°, covering all attitude machining needs, effectively solving the blind spots and tool interference problems of traditional machine tool machining, and adapting to the machining of various complex irregular parts.

[0035] 2. Improved processing efficiency and precision: Multiple processes and multi-directional processing can be completed in one clamping, avoiding repeated positioning errors; precise spindle angle adjustment and high rigidity design of the whole machine ensure stable processing accuracy, and the angle switching time is short, with the overall processing efficiency improved by more than 30% compared with traditional solutions.

[0036] 3. Reduce production input: One machine can replace multiple machine tools with different fixed angles, reducing equipment procurement costs and production space occupation, and simplifying the production process.

[0037] Enhanced process adaptability: It can be widely used in the high-precision machining of complex structural parts such as aerospace impellers, blades, energy equipment gearboxes, and precision mold cavities, adapting to the diverse process requirements of high-end manufacturing fields.

[0038] Example 2 This example provides a specific structural scheme for a full-attitude five-axis turning and milling composite machine tool equipped with a non-orthogonal spindle. This scheme is a structured implementation of the technical concept described in Example 1. The following describes in detail the spatial layout, connection relationship, functional principle, and complete working process of the various components of the machine tool with reference to the accompanying drawings.

[0039] 1. Overall Machine Foundation Layout: The machine tool is based on the bed 7 as its load-bearing base. The bed 7 is made of integral cast iron and has a symmetrical structure with an internal reinforcing rib network to improve the machine's torsional and vibration resistance. Several adjustable feet A10 are distributed at the four corners and center of the bed 7's bottom load-bearing points for adjusting the levelness during equipment installation. Lifting devices 9 are located on both sides of the top of the bed 7; these devices are lifting ring structures welded to the bed for lifting and transport by cranes.

[0040] A linear guide rail is laid above the bed 7 along the Y-axis. The milling and turning table 8 is slidably connected to this guide rail and can reciprocate along the Y-axis under the drive of a servo motor. The milling and turning table 8 is a rotary table with a built-in direct-drive torque motor, which can realize 360° continuous rotation of the C-axis and arbitrary angle indexing and locking. Adjustable feet B11 are provided on the side of the guide rail mounting of the milling and turning table 8 as auxiliary support points to enhance the local rigidity of the table under heavy-load cutting.

[0041] A tool magazine 13 is fixedly installed on one side of the machine bed 7. This tool magazine 13 is a chain-type or disc-type structure, internally divided into turning tool storage positions and milling cutter storage positions, capable of simultaneously accommodating various tools such as external turning tools, internal boring tools, end mills, drills, and taps. The tool magazine 13 is equipped with an automatic tool changer; the tool changing action is driven by a pneumatic system, with a single tool change time of ≤4 seconds.

[0042] A spiral chip conveyor 12 is installed at the outlet of the chip removal groove inside the bed 7, and a composite chip conveyor 16 is installed on the outside of the other side of the bed 7. The spiral chip conveyor 12 collects and transports the chips in the cutting zone to the composite chip conveyor 16. The composite chip conveyor 16 lifts the chips to the chip collection cart through a chain plate or scraper mechanism, realizing continuous and automatic chip discharge.

[0043] 2. Spindle feed system layout: The X-axis transmission system 4 is mounted horizontally above the bed 7. The X-axis transmission system 4 includes a linear motor or ball screw pair, whose mover part or nut seat is fixedly connected to the slide 6, driving the slide 6 to reciprocate along the X direction. The slide 6 is an integral cast iron structure, adapted to the symmetrical casting design of the bed 7. The bottom of the slide 6 fits against the guide rail of the bed 7, and the Z-axis transmission system 2 is vertically mounted on the top.

[0044] The Z-axis transmission system 2 also adopts a linear motor or ball screw drive structure, with its mover or nut seat fixedly connected to the spindle box 3. The spindle box 3 is a box-type structure with an internal bearing support seat for supporting the rotation of the milling spindle 1.

[0045] A balance cylinder 14 is fixedly mounted on the side of the slide 6. The piston rod end of the balance cylinder 14 is hinged to the top or side of the spindle box 3. The air passage of the balance cylinder 14 is connected to the air tank 5 and is equipped with a proportional pressure regulating valve, which can automatically adjust the cylinder output thrust according to the weight of the spindle box 3 and the milling spindle 1 assembly, and realize real-time gravity compensation during the spindle angle change.

[0046] The X-axis transmission system 4 has an air tank 5 and a spindle milling / turning conversion hydraulic station 15 fixedly mounted on the side of the bed guide rail. The air tank 5 is a pressure vessel that provides a stable compressed air source for all pneumatic components of the machine, such as the tool changer, balancing cylinder, and pneumatic clamps. The spindle milling / turning conversion hydraulic station 15 includes a hydraulic pump, an oil tank, a solenoid directional valve, and a locking cylinder. The actuator of the locking cylinder engages with the locking disc of the spindle rotary seat inside the spindle box 3.

[0047] 3. Spindle Assembly Structure: The milling spindle 1 is rotatably mounted inside the spindle box 3. The axis of the milling spindle 1 forms a fixed 45° angle with the horizontal plane, constituting a non-orthogonal spindle structure.

[0048] The milling and turning spindle 1 integrates two independently driven motor systems: the first motor is a torque motor, whose stator is fixed to the spindle housing 3, and whose rotor is fixedly connected to the spindle rotary seat. This motor drives the milling and turning spindle 1 to rotate and adjust around the horizontal axis within the range of -30° to 180°, realizing arbitrary setting of the spindle machining posture.

[0049] The second motor is a high-speed electric spindle motor, whose rotor is connected to the tool clamping system to drive the tool to perform turning or milling cutting motions. The tool clamping system is compatible with turning tool holders and milling cutter holders, and the automatic clamping and release of turning tools / milling cutters is achieved through the tool drawbar mechanism controlled by the spindle turning-milling conversion hydraulic station 15.

[0050] A high-precision angle encoder is coaxially mounted at the tail of the rotary seat of the milling spindle 1. This encoder detects the current rotation angle of the spindle in real time and feeds the position signal back to the CNC system, forming a closed-loop control with the drive command of the first motor. After the spindle reaches the target angle, the milling-turning conversion hydraulic station 15 supplies oil to the locking cylinder. The locking piston pushes out and frictionally locks against the locking disc, achieving rigid locking of the spindle at the target angle. The repeatability accuracy can reach ±5″.

[0051] 4. Five-Axis Linkage Control Principle: The CNC system performs real-time spatial position calculations for the current rotation angle coordinates of the milling spindle 1, the C-axis rotation coordinates of the milling table 8, the X-axis coordinates of the X-axis transmission system 4, the Z-axis coordinates of the Z-axis transmission system 2, and the Y-axis coordinates of the milling table 8. For the 45° non-orthogonal spindle structure, the control system incorporates a nonlinear motion transformation algorithm to map the spatial trajectory of the tool tip to the coordinated motion of each linear axis and rotary axis, achieving blind-zone-free continuous machining of complex spatial surfaces, oblique deep holes, and undercut features.

[0052] 5. Working Process Description Taking the machining of an aerospace-grade irregularly shaped shell part with a spatial oblique hole, outer circular curved surface, and end face groove as an example, the complete working process of the machine tool in this embodiment is as follows: Step 1: Workpiece clamping and tool setting The operator installs the workpiece on the milling and turning table 8 using a special fixture, and adjusts the adjustable feet A10 and B11 to ensure that the horizontal accuracy of the bed 7 and the guide rail support area meets the standard. The CNC system performs a zero-return operation, and each axis returns to the reference point.

[0053] Step 2: The spindle angle adjustment system issues a spindle angle adjustment command based on the machining requirements of the first operation (external turning). The first motor drives the milling spindle 1 to rotate around the horizontal axis to the 90° vertical turning position. During the rotation, the balance cylinder 14 adjusts the thrust in real time according to the proportional pressure regulating valve to counteract the self-weight torque of the spindle box 3 and the milling spindle 1, ensuring smooth movement. The encoder provides real-time feedback of the angle value. After reaching 90°, the system commands the spindle milling conversion hydraulic station 15 to activate, locking the oil cylinder and rigidly fixing the spindle.

[0054] Step 3: Turning Machining. The milling table 8 rotates the workpiece, and the X and Z axes work together to turn the outer diameter and end face. The chips generated during the cutting process are collected by the spiral chip conveyor 12 and conveyed to the compound chip conveyor 16, and continuously discharged from the machine.

[0055] Step 4: Process conversion and automatic tool change. External turning is completed, and the spindle stops. The CNC system instructs the spindle milling / turning conversion hydraulic station 15 to release its locking mechanism. The first motor drives the milling / turning spindle 1 to adjust to the angle required for the next process (e.g., 45° angled hole drilling position). After the angle is reached and locked, the tool magazine 13 selects a drill bit according to the program instructions, and the tool changing robot performs an automatic tool change, with a tool change time ≤ 4 seconds.

[0056] Step 5: Milling / Drilling. The milling table 8 is linked with the X, Y, and Z axes, and in conjunction with the 45° tilt of the spindle, it performs drilling and chamfering on the oblique holes on the side wall of the workpiece. Since the spindle can be set at any angle within the range of -30° to 180°, the drill bit can be fed directly along the normal direction of the oblique hole without workpiece rotation compensation, thus avoiding tool interference.

[0057] Step 6: Five-axis linkage machining of complex curved surfaces. For the spatial irregular curved surface of the workpiece's outer wall, the CNC system starts the five-axis linkage mode. The milling spindle 1 maintains a specific tilt angle, the milling table 8 rotates continuously, the X, Y, and Z linear axes feed synchronously, and the tool always envelops the curved surface in the best cutting posture, completing the machining of all geometric features in one clamping.

[0058] Step 7: After all machining and unloading processes are completed, the spindle returns to the safe position, the milling and turning table 8 moves to the loading and unloading area, and the operator disassembles the finished workpiece, completing one complete machining cycle.

[0059] Example 3 This example provides one implementation of a spindle milling / turning conversion hydraulic station 15, which is the core for realizing rapid switching between milling and turning functions. The system mainly includes an oil tank 25, a valve group 20, an accumulator 21, a motor pump group, and various control valves and monitoring elements.

[0060] Valve assembly 20, serving as the core control unit, is fixed to the oil tank body 25 and integrates a solenoid directional valve, a pressure reducing valve, and a relief valve. Accumulator 21 is connected to the high-pressure side of the system via piping, with a pre-charge pressure P0 of 60 bar and a volume V0 of 1 L. It is used to absorb pressure pulsations, stabilize system pressure, and provide emergency power. An air filter 23 and a level gauge 24 are installed on the oil tank cover 22, and a junction box 19 is used to collect electrical wiring.

[0061] The system adopts a dual pressure source (e.g., 80 bar and 180 bar) combined with an accumulator for pressure stabilization. The oil circuit is switched by the solenoid directional valve in the valve group 20, and multiple actuators are independently controlled: Spindle control circuit: The hydraulic motor or clutch that drives the milling table 8 to rotate is controlled by the three-position four-way solenoid directional valve. The pressure reducing valve adjusts the system pressure to the value required for spindle drive (e.g., 43 bar, 50 bar). The pressure sensor (PI) monitors it in real time.

[0062] A-axis (swivel head axis) control circuit: The hydraulic motor or clamping cylinder that drives the milling spindle 1 to oscillate is controlled by a solenoid valve to achieve precise oscillation and positioning locking of the swivel head. A pressure switch is used to monitor the clamping status and achieve safety interlocking.

[0063] Spindle lock-up / release circuit: This circuit controls the braking of the rotary table spindle (rotating body). Its working logic is as follows: When the spindle milling / turning conversion hydraulic station 15 provides pressure, hydraulic oil drives the braking mechanism to lock the rotary table spindle (rotating body), thus achieving reliable braking lock. When the pressure of the spindle milling / turning conversion hydraulic station 15 is removed or lost, the braking mechanism automatically releases under its own reset function, and the rotary table spindle (rotating body) immediately returns to a free-rotating state. This design ensures that the equipment can reliably lock the spindle when needed and release it without interference during normal machining.

[0064] Tool clamping and releasing circuit: Provides stable pressure (e.g., 6-8 MPa) to the tool electric spindle pull-out mechanism to realize automatic tool clamping and releasing.

[0065] Through the aforementioned integrated hydraulic control, the machine tool can quickly and reliably switch between turning mode (high-speed rotation of the rotary table and the swivel head as a turret) and milling mode (indexing and positioning of the rotary table and participation of the swivel head in five-axis linkage).

[0066] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A five-axis turning and milling composite machining center with a non-orthogonal spindle, comprising a bed (7) and a turning and milling table (8) mounted on the bed (7), characterized in that, Also includes: A slide (6) is movably mounted on the bed (7); an X-axis transmission system (4) is mounted on the bed (7) and drivenly connected to the slide (6) to drive the slide (6) to move along the X-axis; a Z-axis transmission system (2) is mounted on the slide (6); a spindle box (3) is drivenly connected to the Z-axis transmission system (2) to move along the Z-axis; a milling spindle (1) has its spindle axis at a 45° angle to the horizontal plane, forming a 45° non-orthogonal structure, and the milling spindle (1) is rotatably connected to the spindle box (3) and moves around the horizontal axis within a range of -30° to 180°. The machine tool is equipped with a full-attitude angle adjustment system; a balance cylinder (14) is installed on the slide (6) and driven to the spindle box (3) to counteract its own weight when the milling spindle (1) is adjusted; a spindle milling conversion hydraulic station (15) is installed on the X-axis transmission system (4) to lock the milling spindle (1) after the angle adjustment is in place and to realize the conversion between turning mode and milling mode; an encoder is installed on the milling spindle (1) to provide feedback angle positioning signals; the milling worktable (8) is a rotary worktable, which is linked with the milling spindle (1) after the full-attitude angle adjustment to realize five-axis machining.

2. The five-axis turning and milling composite machining center with a non-orthogonal spindle according to claim 1, characterized in that, The bed (7) and the slide (6) are both integrally cast structures, and they are arranged in a symmetrical layout based on the 45° non-orthogonal force characteristics of the milling spindle (1).

3. The five-axis turning and milling composite machining center with a non-orthogonal spindle according to claim 1 or 2, characterized in that, The milling and turning table (8) is slidably mounted on the bed (7) for moving along the Y-axis. An adjustable foot B (11) is provided on one side of the track on the bed (7) for sliding the milling and turning table (8).

4. The five-axis turning and milling composite machining center with a non-orthogonal spindle according to claim 1, characterized in that, The bed (7) is provided with a tool magazine (13) on one side, which is used to store turning tools and milling tools.

5. The five-axis turning and milling composite machining center with a non-orthogonal spindle according to claim 1, characterized in that, The X-axis transmission system (4) is equipped with an air storage tank (5), which provides an air source for the pneumatic components of the equipment.

6. The five-axis turning and milling composite machining center with a non-orthogonal spindle according to claim 1, characterized in that, The bed (7) is provided with a spiral chip conveyor (12), and a composite chip conveyor (16) is provided on one side of the bed (7). The spiral chip conveyor (12) and the composite chip conveyor (16) work together.

7. The five-axis turning and milling composite machining center with a non-orthogonal spindle according to claim 1, characterized in that, The bed (7) is equipped with a whole machine lifting device (9), and the bed (7) is provided with several adjustable feet A (10) for adjusting the installation level.

8. The five-axis turning and milling composite machining center with a non-orthogonal spindle according to claim 1, characterized in that, The milling spindle (1) is equipped with a first motor and a second motor. The first motor is used to drive the milling spindle (1) to rotate around the horizontal axis to adjust the angle. The second motor is used to drive the cutting tool of the milling spindle (1) to rotate.

9. The five-axis turning and milling composite machining center with a non-orthogonal spindle according to claim 1, characterized in that, The encoder is a high-precision encoder, which is connected to the spindle milling conversion hydraulic station (15) and the control system signal to achieve spindle angle repeatability accuracy of ±5″.

10. A five-axis turning and milling composite machine tool with a non-orthogonal spindle, comprising a bed (7) and a slide (6) disposed on the bed (7), characterized in that, Also includes: The milling and turning table (8) is slidably mounted on the bed (7) for moving along the Y-axis; the X-axis transmission system (4) is mounted on the bed (7) and drivenly connected to the slide (6); the Z-axis transmission system (2) is mounted on the slide (6); the spindle box (3) is drivenly connected to the Z-axis transmission system (2); the milling and turning spindle (1) has its spindle axis at a 45° angle to the horizontal plane, is rotatably connected to the spindle box (3), and can be adjusted in all posture angles from -30° to 180° around the horizontal axis; the milling and turning table (8) is linked with the milling and turning spindle (1) to complete the turning, milling, drilling, and boring operations in one clamping.

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