Multi-station integrated tool quick change structure for numerical control machine tool

Abstract

The application discloses a multi-station integrated tool quick change structure of a numerical control machine tool, which comprises a device shell, an inner cavity of which is circular, two symmetrical side openings are arranged on the device shell, two independent tool changing manipulators are arranged on the same tool magazine, different machine tool spindles are respectively connected to the two independent tool changing manipulators, tool changing actions are completed at the fixed openings of the side of the shell, the target tool is directly sent to any opening through index rotation, the tool changing path is the shortest straight line distance, the complex space motion track of the manipulator in the traditional scheme is avoided, the multi-outlet design is especially suitable for complex machining scenes which require high-speed and parallel tool changing, the overall tool changing waiting time can be significantly shortened, and the machining pace and flexibility of the machine tool are greatly improved; the device is full-mechanical transmission, direct and reliable action, the system does not need hydraulic and pneumatic devices, and the energy consumption, maintenance cost and leakage risk are reduced.

Description

Technical Field

[0001] This invention relates to the field of CNC machine tool technology, specifically to a multi-station integrated quick-change tool structure for CNC machine tools. Background Technology

[0002] In modern CNC machining centers, the automatic tool changer (ATC) system is a core component for achieving efficient and continuous machining. Traditional automatic tool changers typically use chain-type or disc-type tool magazines in conjunction with robotic arms for tool changing. While these systems are technologically mature, they generally suffer from problems such as complex structure, large footprint, long tool change paths, inconvenient maintenance, and high cost. Especially for small and medium-sized CNC machine tools or machining units, the large tool magazines and tool changing mechanisms occupy valuable internal machine space, increasing overall cost and complexity.

[0003] Existing technologies also include some highly integrated tool magazine designs, such as integrating the tool magazine directly into the machine tool table or near the spindle. However, these designs have limitations in achieving simultaneous and synchronous rapid replacement of multiple tools. The common practice is to replace only one tool at a time, or to use a complex multi-axis robotic arm to grasp them sequentially, which is inefficient. How to achieve synchronous control of multiple chuck movements through a single drive source in a compact modular structure, so as to push multiple tools simultaneously and synchronously from the storage position to the tool change position, in order to cooperate with an external robotic arm for efficient dual-tool or multi-tool exchange, is a technical problem that those skilled in the art are committed to solving. Summary of the Invention

[0004] (a) Technical problems to be solved To address the shortcomings of existing technologies, this invention provides a multi-station integrated tool quick-change structure for CNC machine tools, thus solving the aforementioned technical problems.

[0005] (II) Technical Solution To achieve the above objectives, the present invention provides the following technical solution: a multi-station integrated tool quick-change structure for CNC machine tools, comprising: Device housing: It has a circular inner cavity inside, and the side wall of the inner cavity has two symmetrical side openings, which serve as interfaces for exchanging tools with external machine tool spindles or tool changing robots.

[0006] Cover: It is detachably connected to the top opening of the device housing to facilitate the installation, debugging and maintenance of the tool magazine.

[0007] Tool magazine storage mechanism: installed in the inner cavity for storing and holding multiple tools, the mechanism includes: a rotating shaft: rotatably supported at the bottom center of the inner cavity by bearings.

[0008] Multiple tool clamping units are arranged uniformly and fixedly along the circumference of the rotation axis.

[0009] The specific structure of the tool clamping unit is as follows: Each unit includes a radial protrusion fixed on a rotating shaft, the end of which is provided with a radially extending sliding cavity; a sliding rod that slides in conjunction with the sliding cavity, the outer end of which is used to install a jaw for clamping the tool; and a screw that is threadedly connected to the sliding rod. An axial limiting groove is provided on the top inner wall of the sliding cavity, the screw passes upward through this limiting groove, and its top end is connected to a guide shaft.

[0010] Motion conversion and drive mechanism: Located between the cover and the tool magazine storage mechanism, it converts linear drive into radial motion of a specific tool clamping unit. This mechanism includes: Arc-shaped guide rail: Fixedly installed at the bottom of the cover, the arc-shaped guide rail extends to cover the corresponding circumferential angle range between the two side openings.

[0011] Push block: Located on the radial outer side of the arc-shaped guide rail, it can be driven by an independent horizontal linear drive mechanism to perform linear reciprocating motion. The push block is provided with an arc-shaped groove that matches the curvature of the fixed arc-shaped guide rail. A V-shaped groove for driving the guide shaft is opened in the arc-shaped groove. The movement stroke of the push block can serve and precisely align with the two side openings respectively.

[0012] Indexing drive motor: Installed at the bottom of the device housing, its output shaft is directly or through a transmission mechanism connected to the rotating shaft, used to drive the entire tool magazine storage mechanism to perform precise indexing rotation, so as to send the target tool to any tool changing station at any side opening.

[0013] This invention also provides a tool changing method based on the above-described quick-change structure, characterized by comprising the following steps: S1. Indexing and positioning: The control system receives the tool change command, drives the motor to rotate the rotating shaft, and rotates the station unit where the target tool group is located to the tool change position, so that the two jaws and the tool of the unit are aligned with the two symmetrical side openings respectively.

[0014] S2. Synchronous ejection: The horizontal synchronous ejection mechanism is activated, and its horizontal drive source drives the two ejection sliders to make synchronous opposite linear movements. The action output ends of the front ends of the two ejection sliders simultaneously push the rear ends of the two target jaws, forcing the jaws to reach the preset tool change waiting position.

[0015] S3, Tool Exchange: The external robotic arm picks up the two new tools that have been pushed out, and then rotates or moves them to place the two old tools between the two open jaws.

[0016] S4. Synchronous retraction: The horizontal synchronous ejection mechanism is driven in reverse, causing the two ejection sliders to move synchronously in opposite directions and retract.

[0017] S5, Reset and Standby: The drive motor drives the rotating shaft to rotate again, causing the tool-changed station to leave the tool-changing position, and the entire structure returns to the standby state.

[0018] Compared with existing technologies, this invention provides a multi-station integrated tool quick-change structure for CNC machine tools, which has the following advantages: By setting two symmetrical side openings, two independent tool-changing robots can be configured on the same tool magazine, respectively docking with different machine tool spindles. The tool exchange action is completed only at the fixed opening on the side of the housing. The target tool is directly sent to either opening through indexing rotation. The tool change path is the shortest straight-line distance, avoiding the complex spatial movement trajectory of the robot in traditional solutions. The multi-outlet design is particularly suitable for complex machining scenarios that require high-speed, parallel tool changing, which can significantly shorten the overall tool change waiting time and greatly improve the machining cycle and flexibility of the machine tool. Through the horizontal synchronous push mechanism, the synchronous push and retraction of the two tools are realized, and the tool change action is coordinated and consistent. It is suitable for machining scenarios that require symmetrical tool changing. Moreover, the device is a fully mechanical transmission, and the action is direct and reliable. The system does not require hydraulic or pneumatic devices, which reduces energy consumption, maintenance costs and leakage risks. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the main structure of the present invention; Figure 2 This is a cross-sectional structural diagram of the cover, device housing, and rotating shaft of the present invention. Figure 3 This is a schematic diagram showing the separation structure of the cover, inspection cover, and rotating shaft of the present invention. Figure 4 This is a schematic diagram showing the separation structure of the cover, protruding rod, and device housing of the present invention. Figure 5 This is a schematic diagram showing the separation structure of the cover, protruding rod, and device housing of the present invention. Figure 6 This is a top view of the cover, guide groove, and gripper structures of the present invention.

[0020] Wherein: 1. Device housing; 11. Inner cavity; 12. Side opening; 13. Second connecting part 2. Cover; 21. First connecting part; 22. Guide rail; 23. Guide groove; 3. Horizontal drive mechanism; 31. Drive mechanism; 32. Transmission cavity; 33. Transmission gear; 34. Inspection cover; 35. Transmission slider; 36. Push block; 37. Tooth groove; 38. Rectangular slide groove; 39. Arc groove; 310. V-groove; 4. Storage mechanism; 41. Stepper motor; 42. Connecting end; 43. Rotating shaft; 44. Sliding cavity; 45. Sliding rod; 46. Connecting rod; 47. Claw; 48. Protruding rod; 49. Screw; 410. Guide shaft; 411. Limiting groove. Detailed Implementation

[0021] The embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and should not be construed as limiting the scope of the invention.

[0022] In the description of this invention, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0023] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0024] Please see Figure 1-6 The CNC machine tool multi-station integrated tool quick-change structure has a cylindrical device housing 1 as its main body. The housing 1 has a circular inner cavity 11 machined inside. A side opening 12 is opened on the side wall of the inner cavity 11, which serves as the only channel for exchanging tools with the outside. The top of the housing 1 is open and is connected to the cover 2 by bolts. The cover 2 is provided with a first connecting part 21, and the housing 1 is provided with a corresponding second connecting part 13, so as to realize detachable fastening.

[0025] At the bottom center of the device housing 1, a stepper motor 41 is installed. The output axis of the stepper motor 41 extends upward, and its top end is machined with a docking end 42 with a regular hexagonal cross section.

[0026] The core of the tool magazine storage mechanism is a vertically arranged rotating shaft 43, which is rotatably supported in the inner cavity 11 by bearings. The bottom end of the rotating shaft 43 has a regular hexagonal docking groove that perfectly matches the shape of the docking end 42, which is directly fitted onto the docking end 42 to achieve gapless power transmission. Along the circumference of the rotating shaft 43, multiple radially protruding protrusions 48 are evenly welded. The protrusions 48 are rectangular cross-section steel parts, which are keyed to the rotating shaft 3 and welded for reinforcement. Each protrusion 48 has a tool clamping unit at its end.

[0027] Each tool clamping unit includes: a radial sliding cavity 44 machined in the protrusion 48, and a sliding rod 45 that can slide in the sliding cavity 44; a chuck 47 connected to the outer end of the sliding rod 45 by a connecting rod 46, the shape of the chuck 47 matching the groove on the standard tool holder; a screw 49 screwed into the threaded hole at the inner end of the sliding rod 45; a limiting groove 411 is formed on the top inner wall of the sliding cavity 44; and a guide shaft 410 extends upward from one end of the screw 49 through the limiting groove 411.

[0028] The motion conversion and drive mechanism is used to control the motion state of the guide shaft 410. An arc-shaped guide rail 22 is fixedly installed at the bottom of the cover 2. The guide rail has a guide groove 23. Inside the cover 2, there is a horizontal linear drive assembly 3. This assembly includes a servo motor mounted on the inspection cover 34 as a drive mechanism 31. The servo motor drives a transmission gear 33 to rotate. Two transmission sliders 35 are symmetrically arranged on both sides of the gear and are slidably installed in the transmission cavity 32 of the cover 2. The tooth grooves 37 on the sliders mesh with the transmission gear 33. The bottom of each of the two transmission sliders 35 is connected to a push block 36 by screws. The lower surface of the push block 36 has an arc-shaped groove 39 with the same curvature as the fixed guide rail 22. A V-shaped groove 310 is machined in the middle of the arc-shaped groove 39.

[0029] During installation, the stepper motor 41 is securely mounted on the bottom base of the device housing 1, ensuring that the axis of the mating end 42 on its output shaft coincides with the center line of the circular inner cavity 11 of the housing. The rotating shaft 43 is mounted in the inner cavity 11 through the bearing, and its bottom mating groove is aligned with the regular hexagonal mating end 42 of the stepper motor and pressed in. Subsequently, multiple tool clamping units are evenly fixed in the protrusions 48 on the rotating shaft 43 along the circumference.

[0030] Install the upper mechanism: Install the arc-shaped guide rail 22 at the bottom of the cover 2, put the drive source, transmission gear 33, transmission slider 35, etc. into the transmission cavity 32, install the inspection cover 34, and connect the two push blocks 36 to the bottom of the transmission slider 35.

[0031] Final assembly: The assembled cover 2 is hoisted above the device housing 1, ensuring that the guide shafts 410 of all tool clamping units can smoothly enter the guide grooves 23 of the arc-shaped guide rail 22, and then the cover is fastened to the housing through the first connecting part 21 and the second connecting part 13.

[0032] Debugging: Connect the control system and adjust the indexing angle of the stepper motor 41 to ensure that each station can be accurately aligned with the side opening 12. Adjust the stroke of the horizontal drive mechanism 31 to ensure that the push block 36 can accurately form an annular channel and complete the engagement and disengagement actions with the guide shaft 410 when it moves.

[0033] The tool changing method based on this structure is an automated closed-loop process, controlled and executed by a numerical control system (CNC) or a programmable logic controller (PLC). The specific steps are as follows: Step S1: Tool Change Command Response and Tool Selection: The CNC system issues a tool change command according to the machining program, controls the stepper motor 41 to drive the rotating shaft 43 to rotate by a predetermined angle, and quickly and accurately rotates the clamping unit storing the target tool to the tool change position directly opposite the opening 12 on the side of the device housing. The closed-loop control of the stepper motor ensures the absolute accuracy of tool selection.

[0034] Step S2: After the tool is selected, the drive source of the horizontal drive mechanism 31 is immediately started, driving the transmission gear 33 to rotate, which in turn drives the two transmission sliders 35 and the bottom push block 36 to move in opposite directions along the guide rail. At this time, the guide shaft 410 of the target clamping unit is embedded in the V-groove 310 on the push block 36. The push block continues to move in opposite directions, and the guide shaft 410 is forced to slide outward radially through the inclined surface of the V-groove. The guide shaft 410 drives the screw 49 to move outward, which in turn drives the sliding rod 45 to extend outward, and finally the pawl 47 connected to the end of the sliding rod extends out of the side opening 12.

[0035] Step S3: Tool exchange: The external tool changing robot accurately grasps the tool holder through the side opening 12, removes it from the chuck 47 and removes it. Then, the robot feeds in the replaced tool and precisely places its tool holder on the chuck 47.

[0036] Step S4: Tool clamping: After the external robot confirms that the tool is in place, it sends a signal, and the horizontal drive mechanism 31 immediately reverses the drive, causing the two push blocks 36 to move in opposite directions in a straight line. The push blocks drive the guide shaft 410 310 to move radially inward. The guide shaft 410 drives the screw 49 to move inward, which in turn drives the chuck 47 to retract into the inner cavity. At this time, the arc grooves 39 on the two push blocks 36 are connected with the guide groove 23 to form a complete annular groove, which allows multiple guide shafts 410 to slide in the annular groove.

[0037] Step S5: Reset and standby: Stepper motor 41 is triggered again, driving the rotating shaft 43 to rotate a small angle, so that the station that just completed the tool change is slightly away from the tool change port, avoiding interference while preparing for the next tool change command. The entire quick change structure returns to the standby state, waiting for the next tool change cycle.

[0038] Example 2: For cost-sensitive or speed-required applications, the horizontal linear drive mechanism can be replaced with a dual-position cylinder, with the L1 and L2 strokes positioned by a precision mechanical stop or magnetic switch, and the indexing drive motor 16 can be a stepper motor in conjunction with a zero-point sensor.

[0039] In this specification, the clamping and releasing mechanism of the chuck, which achieves clamping and releasing of the standard tool holder through its axial displacement, and the working principle of the elastic deformation of the chuck and the engagement of the tool holder pull stud or groove, are common knowledge in the field of CNC machine tools. There are many mature and universal technical solutions available for selection and application. Therefore, in order to avoid redundancy and highlight the innovation of this invention, this document will not elaborate on the specific clamping mechanism of the chuck. Those skilled in the art, based on the overall solution of this invention, can directly and without doubt select a suitable chuck structure to achieve reliable tool fixation.

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

Claims

1. A multi-station integrated quick-change tool structure for CNC machine tools, characterized in that, include: The device housing (1) has a circular inner cavity (11) inside, and the side wall of the inner cavity (11) has a side opening (12). The cover (2) is detachably connected to the top opening of the device housing (1); The tool magazine storage mechanism includes a rotating shaft (43) rotatably mounted in the inner cavity (11) and a plurality of tool clamping units arranged circumferentially along the rotating shaft (43); A motion conversion and drive mechanism is disposed between the cover (2) and the tool magazine storage mechanism; And a drive motor, located at the bottom of the housing (1) of the device, for driving the rotating shaft (43) to perform indexing.

2. The multi-station integrated quick-change tool structure for CNC machine tools according to claim 1, characterized in that, The tool clamping unit includes: A protruding rod (48) is fixed on the rotating shaft (43), and the end of the protruding rod (48) is provided with a sliding cavity (44) extending radially. A sliding rod (45) is slidably installed in the sliding cavity (44), and the outer end of the sliding rod (45) is connected to a claw (47) via a connecting rod (46). And a screw (49), which is threadedly connected to the sliding rod (45); The sliding cavity (44) has a limiting groove (411) on its top inner wall. The screw (49) is connected to a guide shaft (410) on its upward-extending end face through the limiting groove. The movement of the guide shaft (410) can drive the screw (49) to move, thereby causing the sliding rod (45) and the claw (47) to extend and retract radially.

3. The multi-station integrated quick-change tool structure for CNC machine tools according to claim 2, characterized in that, The motion conversion and driving mechanism includes: At least one arc-shaped guide rail (22) is provided at the bottom of the cover (2), and a guide groove (23) is provided on the guide rail (22). At least one push block (36) driven by a drive mechanism (31), wherein an arc groove (39) is provided on the push block (36); When the push block (36) moves to a preset position, the arc groove (39) on it connects with the guide groove (23) on the guide rail (22) to form an annular channel for the guide shaft (410) to slide. The linear motion of the push block (36) drives the guide shaft (410) to move by changing the shape of the annular channel.

4. The multi-station integrated quick-change tool structure for CNC machine tools according to claim 3, characterized in that, The drive mechanism (31) is a horizontal linear drive assembly, which includes: The drive source is installed on the cover (2); The transmission gear (33) is driven to rotate by the drive source; And two symmetrically arranged transmission sliders (35) are slidably installed inside the cover (2), and are provided with tooth grooves (37) that mesh with the transmission gear (33). The two push blocks (36) are detachably connected to the bottom of the two transmission sliders (35).

5. The multi-station integrated quick-change tool structure for CNC machine tools according to claim 4, characterized in that, The cover (2) has a transmission cavity (32) inside, the transmission gear (33) and the transmission slider (35) are disposed in the transmission cavity (32), and the top of the transmission cavity (32) is provided with a detachable maintenance cover (34).

6. The multi-station integrated quick-change tool structure for CNC machine tools according to claim 3, characterized in that, A V-shaped groove (310) is provided in the middle of the inner wall of the arc groove (39) on the push block (36); When the push block (36) moves under the drive of the drive mechanism (31) to engage with the guide shaft (410), the pawl (47) can be pushed to move horizontally.

7. The multi-station integrated quick-change tool structure for CNC machine tools according to claim 1, characterized in that, The cover (2) and the device housing (1) are detachably connected by a connecting part. The cover (2) is provided with a first connecting part (21), and the device housing (1) is provided with a second connecting part (13) that is adapted to it.

8. The multi-station integrated quick-change tool structure for CNC machine tools according to claim 1, characterized in that, The drive motor is a stepper motor (41), and its output shaft end is provided with a docking end (42) with a cross-section of a regular polygon; the bottom end of the rotating shaft (43) is provided with a docking groove that is compatible with the docking end (42).

9. The multi-station integrated quick-change tool structure for CNC machine tools according to claim 8, characterized in that, The cross-section of the docking end (42) is a regular hexagon.

10. The tool changing method with a quick-change structure according to any one of claims 1-9, characterized in that, Includes the following steps: S1. Tool change command response: The control system receives the tool change command, and the stepper motor (41) drives the rotating shaft (43) to rotate, rotating the tool clamping unit where the target tool is located to the tool change station aligned with the side opening (12); S2, Tool release: The horizontal drive mechanism (3) is activated, driving the two push blocks (36) to move in opposite directions, forcing the guide shaft (410) in the target tool clamping unit to be inserted into the V-groove (310) and move horizontally, thereby driving the sliding rod (45) to extend radially outward, so that the two claws (47) extend out from the two side openings respectively; S3, Tool exchange: The external robot arm removes the old tool through the side opening (12) and inserts a new tool; S4, Tool clamping: The horizontal drive mechanism (3) drives in the opposite direction, causing the two push blocks (36) to move towards each other, forcing the guide shaft (410) to be driven by the push blocks, thereby causing the sliding rod (45) to drive the pawl (47) to retract into the inner cavity; S5, Reset and standby: The rotating shaft (43) rotates, causing the tool-changing station to leave the side opening (12), and the structure returns to the standby state.

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