Medical mold femtosecond laser processing positioning tooling

Abstract

The application provides a medical mold femtosecond laser processing positioning tool, and relates to the technical field of femtosecond laser precision machining, comprising a laser workbench, a feeding conveyor belt and a floating transmission group, the laser workbench is a rotatable multi-station rotary table, each station is provided with a negative pressure adsorption hole, the floating transmission group is arranged between the conveyor belt and the workbench, an adaptive floating adjustment mechanism composed of a floating block, a spring, a ball head and a ball is arranged in the support block, when feeding, the floating transmission group picks up and pushes the mold, the necked-in inclined surface block on the side surface of the mold cooperates with the guide block slot inclined surface of the workbench to generate a guiding force, the floating block is driven to slightly translate and rotate in the support block, so that the position and angle deviation of the mold are automatically corrected, automatic alignment and clamping without stress are realized, the application solves the problems of precision loss and product damage caused by secondary clamping and alignment error of the medical mold in femtosecond laser processing, and improves the processing efficiency and consistency.

Description

Technical Field

[0001] This invention relates to the field of femtosecond laser precision machining technology, and in particular to a positioning fixture for femtosecond laser machining of medical molds. Background Technology

[0002] Femtosecond lasers, due to their cold processing and ultra-high precision characteristics, demonstrate significant advantages in manufacturing high-value medical devices such as bioresorbable microneedles and interventional catheters with complex microstructures. These devices are typically tiny, structurally complex, and made of special materials. The manufacturing process usually involves: first, placing a pre-formed device into a specialized medical mold of a matching shape, which serves to fix, support, and precisely position the device during subsequent processing; then, placing the mold containing the device into a femtosecond laser processing system to perform microstructural processing on the device within the mold.

[0003] However, while femtosecond laser processing systems possess high-precision motion platforms, the assembly of medical molds and instruments is a separate process. When loading the assembled mold and instrument assembly onto the laser processing platform, secondary clamping and alignment are required. This secondary clamping and alignment often necessitates additional precision adjustment mechanisms or manual fine-tuning, making the process complex and inefficient. Furthermore, during clamping, traditional rigid clamping components, when pressing and squeezing the mold, are prone to causing localized pressure that penetrates the mold and impacts the delicate medical device, affecting its internal fragility and reducing processing precision. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a femtosecond laser processing positioning fixture for medical molds. This fixture can automate the entire process of medical mold processing from loading, precise positioning, rotation processing, detection and unloading, and eliminate the potential damage risk to precision instruments caused by rigid clamping, thereby improving processing accuracy and efficiency.

[0005] This invention provides the following technical solution: A femtosecond laser processing and positioning fixture for medical molds includes a laser worktable, a feeding conveyor belt, and a floating transport assembly. The laser worktable is a horizontal turntable with at least one set of stations for positioning the medical molds distributed circumferentially on its horizontal surface. The feeding conveyor belt transports the medical molds to a side close to the laser worktable. The floating transport assembly is located between the end of the feeding conveyor belt and the laser worktable, receiving the medical molds from the feeding conveyor belt and adaptively adjusting their position and angle before transferring and positioning the medical molds onto the stations on the laser worktable.

[0006] Its technical advantages are: it constructs a basic but complete framework for an automated positioning system, and by setting up a dedicated floating transmission group, it provides core functional units for eliminating loading alignment errors and achieving high-precision stress-free handover.

[0007] Furthermore, the horizontal turntable has four sets of workstations evenly distributed circumferentially on its horizontal platform, defined as loading, processing, inspection, and unloading positions. The turntable has an external gear ring around its periphery, which is driven by a rotary motor for indexing. Each workstation has a set of support block slots, and multiple negative pressure adsorption holes are arranged around the periphery of these slots. These negative pressure adsorption holes are connected to a negative pressure fan via independent adsorption pipes, and controlled solenoid valves are installed on these adsorption pipes.

[0008] Its technical advantages are as follows: by setting up a four-station rotary indexing table, the feeding, processing, inspection and unloading processes are made continuous and integrated, which improves equipment utilization and production efficiency; at the same time, the use of negative pressure adsorption for positioning provides a stable reference without mechanical clamping stress for subsequent processing, protecting the precision instruments inside the mold.

[0009] Furthermore, the adsorption pipeline includes an adsorption chamber, an adsorption tube, and a central suction tube corresponding to each workstation. The bottom of the negative pressure adsorption hole at each workstation is connected to an independent adsorption chamber, and each adsorption chamber is connected to the central suction tube located at the center of the horizontal turntable via an adsorption tube equipped with the solenoid valve. The central suction tube is connected to the negative pressure fan via a rotary joint.

[0010] Its technical advantages are as follows: by adopting the design of independent adsorption chamber and central suction tube combined with rotary joint, it realizes independent and precise control of negative pressure adsorption at each station on the rotating worktable, solves the problem of air circuit connection and sealing under dynamic rotation conditions, and ensures the reliability of positioning at each station.

[0011] Furthermore, the floating transmission assembly includes a base frame, a lifting cylinder, a support rail, a support block, and a push cylinder. The driving end of the lifting cylinder is connected to the base frame and is used to drive the base frame to rise and fall. The support rail is horizontally mounted on the base frame. The support block is slidably disposed on the support rail. The driving end of the push cylinder is connected to the support block and is used to drive the support block to slide along the support rail. A floating block for supporting the medical mold is provided on the top side of the support block.

[0012] Its technical advantages are: it clarifies the basic mechanical structure of the floating conveyor group, realizes the transfer of materials from the conveyor belt to the worktable through lifting and horizontal movement, and provides a structural basis for subsequent precise adaptive alignment by setting floating blocks.

[0013] Preferably, the top side of the support block is also provided with a plurality of upper balls, the top of which is flush with the top side plane of the floating block.

[0014] Its technical advantages are as follows: the upper ball bearing and the floating block jointly support the mold, which not only ensures that there is enough static friction between the floating block and the bottom surface of the mold to transmit the adjustment force, but also provides low-resistance rolling support when the mold is adjusted by floating, reducing the adjustment resistance and making fine adjustment smoother and more sensitive.

[0015] Furthermore, a slot is formed within the support block, and the floating block, being a cylindrical block, is accommodated within the slot. A lower ball bearing is provided on the bottom side of the floating block, and the lower ball bearing forms rolling contact with the bottom of the slot. Multiple pairs of limiting blocks are provided on the circumferential side of the floating block. An adjusting rod corresponding to each pair of limiting blocks is also inserted and installed within the support block. One end of the adjusting rod is provided with a ball head that abuts against the side of the floating block, and the other end abuts against a compression spring.

[0016] Its technical advantages are as follows: it specifically discloses the core mechanical structure of the floating adjustment mechanism. The lower ball provides a low-friction moving base for the floating block in the horizontal plane; the adjusting rod, ball head, and compression spring form an elastic abutment system, which allows the floating block to move under force and provides a return force to reset it; the limit block effectively prevents the floating block from being over-adjusted, ensuring the controllability and safety of the adjustment process.

[0017] The floating block can be adjusted by translation and rotation within the range defined by the slot under the combined action of the abutting force applied by the compression spring through the ball head, the rolling support of the lower ball, and the limiting action of the limiting block.

[0018] Its technical advantages lie in clarifying the motion mechanism of the floating block. This structure allows the floating block to smoothly translate and rotate under the action of external forces (such as guiding forces) and overcome spring forces. Once the external forces disappear or balance, it can reset or maintain its new position under the action of the spring. This design enables passive, adaptive fine-tuning of the position and angle of the medical mold, compensating for accumulated transmission errors, and is key to achieving high-precision, flexible alignment.

[0019] Furthermore, the medical mold has a set of constricted bevel blocks on the side near the laser worktable. Each station of the laser worktable has a corresponding set of guide block slots for docking and guiding with the constricted bevel blocks.

[0020] Its technical effect is that it provides a physical interface for triggering and guiding floating adjustments. By cooperating with the beveled surface of the constriction bevel block on the mold and the beveled surface of the guide block slot on the worktable, the macroscopic positional deviation is converted into a guiding force during the pushing process. This guiding force acts precisely on the mold and is then transmitted to the floating block, thereby automatically and flexibly guiding and correcting the mold to a precise predetermined position, realizing automatic centering at the physical level.

[0021] Furthermore, the positioning fixture also includes an unloading conveyor belt. The unloading conveyor belt is located on the unloading side of the laser worktable and is used to deliver the processed medical mold. The loading and unloading conveyor belts have the same structure, both including two sets of conveyor belts, and a floating transfer assembly is also provided between the two sets of conveyor belts of the unloading conveyor belt for transporting the medical mold from the unloading position onto the two sets of conveyor belts.

[0022] Its technical advantages lie in: perfecting the closed-loop process of the automated production line. The symmetrical unloading conveyor belt and its floating transmission group enable high-precision, non-destructive unloading of the processed mold from the worktable to the unloading conveyor belt. The entire system automates the entire process of loading, processing, inspection, and unloading, improving the overall continuity and efficiency of operations.

[0023] Furthermore, the present invention also provides a method for loading and positioning a medical mold, applied to the positioning fixture described in any of the preceding claims, comprising the following steps: S1: transporting the medical mold to the receiving position of a floating transmission group via a loading conveyor belt; S2: driving the floating transmission group to rise, causing the floating block of the floating transmission group to contact and lift the medical mold, thus detaching it from the loading conveyor belt; S3: driving the support block of the floating transmission group to move towards the loading position of the laser worktable, thereby moving the medical mold toward the loading position; S4: during the movement, a guiding force is generated by the engagement of the constricted inclined block on the medical mold with the inclined surface of the guide block slot on the loading position, and the guiding force drives the floating block to float and adjust within the support block, thereby causing the medical mold to make fine adjustments to its position and / or angle, so that it is precisely aligned with the support block slot on the loading position; S5: placing the medical mold on the loading position and fixing it by negative pressure adsorption; S6: the floating transmission group descends and returns to its initial position, completing the loading.

[0024] The beneficial effects of this invention are: 1: Through the coordinated operation of the horizontal turntable, floating conveyor group and loading / unloading conveyor belt, the unmanned and automated closed-loop flow of medical molds from loading, precision positioning, rotary processing, online detection and unloading is realized, which significantly improves production efficiency; 2: The mold is fixed on the work station by negative pressure adsorption, which avoids the compressive stress generated by traditional rigid clamping and prevents the stress from being transmitted through the mold to the brittle precision medical device inside, thus fundamentally ensuring the stability of the processing benchmark and the processing accuracy of the final product. 3: Through its unique floating transmission group structure, it can automatically compensate for the alignment error generated during the transmission of medical molds. By utilizing the guiding cooperation of the constricted inclined block and the guide block slot, combined with the synergistic effect of the floating block, ball head, spring, lower ball and limit block, the position and angle of the mold are automatically and flexibly adjusted in real time during the mold transfer process. This ensures that the mold can be accurately and without impact aligned and placed in the support block slot of the station, solving the problem of precise alignment in the last stage of automated feeding. 4. The loading and unloading conveyors adopt the same structure and are equipped with independent floating transmission groups, realizing bidirectional symmetrical automated material transfer. The four-station horizontal turntable integrates core processes and detection functions, with a compact layout. The negative pressure adsorption, floating transmission, and rotary indexing functional modules work together, resulting in high system reliability and high space utilization. Attached Figure Description

[0025] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings: Figure 1 This is a top view schematic diagram of the positioning fixture of the present invention; Figure 2 This is a top view schematic diagram of the floating transmission group between conveyor belts in this invention; Figure 3 This is a schematic cross-sectional view of the floating block inside the support block in this invention; Figure 4 This is a front view schematic diagram of the floating transmission group in this invention; Markings in the diagram: 1. Laser worktable; 2. Floating conveyor group; 3. Loading conveyor belt; 4. Unloading conveyor belt; 5. Medical mold; 11. Horizontal turntable; 12. Rotary motor; 13. Guide block slot; 14. Support block slot; 15. Negative pressure suction hole; 16. Suction tube; 17. Central suction tube; 2a. Loading floating conveyor group; 2b. Unloading floating conveyor group; 21. Base frame; 22. Lifting cylinder; 23. Support rail; 24. Support block; 25. Push cylinder; 241. Floating block; 242. Lower ball bearing; 243. Limiting block; 244. Adjusting rod; 245. Ball head; 246. Compression spring; 247. Upper ball bearing; 51. Shrinking inclined block; A. Loading position; B. Processing position; C. Detection position; D. Unloading position. Detailed Implementation

[0026] Example 1: See Figures 1 to 4 The positioning fixture in this embodiment mainly includes a laser worktable 1, a feeding conveyor belt 3 and a floating transmission group 2. The floating transmission group 2 in this embodiment is the feeding floating transmission group 2a.

[0027] The core of the laser worktable 1 is a horizontal turntable 11. The turntable 11 has an external gear ring on its edge, driven by a rotary motor 12 via gears, enabling precise 90-degree indexing rotation. Four workstations are evenly arranged circumferentially on the surface of the turntable 11: loading station A, processing station B, inspection station C, and unloading station D. Each workstation has a guide block slot 13 and a support block slot 14. Around the support block slot 14, multiple negative pressure suction holes 15 are distributed. These suction holes 15 connect downwards to an independent suction chamber (not shown in the figure), with the four workstations corresponding to four independent suction chambers. Each suction chamber is connected to a central suction pipe 17 located at the center of the turntable 11 via a suction pipe 16 equipped with a solenoid valve. The central suction pipe 17 is connected to an external negative pressure fan via a rotary joint. When a specific workstation (such as the loading position A where the mold has been placed) needs to be fixed, the control system opens the solenoid valve of the corresponding workstation. The negative pressure passes through the central suction tube 17, the suction tube 16, and the suction chamber to the negative pressure suction hole 15, firmly adsorbing the mold 5 onto the table surface to achieve stress-free precision positioning.

[0028] The feeding conveyor belt 3 is used to transport the medical mold 5 to one side near the laser worktable 1. The floating transmission group 2 is located between the end of the feeding conveyor belt 3 and the laser worktable 1, and includes a base frame 21, a lifting cylinder 22, a support rail 23, a support block 24, and a push cylinder 25. The lifting cylinder 22 drives the base frame 21 to rise and fall. The support rail 23 is horizontally mounted on the base frame 21. The support block 24 is slidably mounted on the support rail 23 and is driven by the push cylinder 25 to reciprocate along the support rail 23.

[0029] The support block 24 is the core component of this embodiment. It has an internal slot to accommodate a cylindrical floating block 241. The bottom of the floating block 241 forms rolling contact with the bottom of the slot via lower ball bearings 242, allowing it to move slightly with low resistance in the horizontal plane. Multiple pairs of limiting blocks 243 are arranged circumferentially on the side of the floating block 241. An adjusting rod 244 is correspondingly installed on the support block 24. One end of the adjusting rod 244 is a ball head 245 that elastically abuts against the cylindrical surface of the floating block 241, and the other end is pressed by a compression spring 246, thereby providing the floating block 241 with an elastic restoring force tending towards the center position. Several upper ball bearings 247 are also installed on the top of the support block 24, their tops flush with the top of the floating block 241, jointly supporting the mold 5.

[0030] The medical mold 5 has a set of constricted inclined blocks 51 on the side near the laser worktable 1, which are used to dock and guide with the guide block slots 13 on each station of the laser worktable 1.

[0031] The workflow of this embodiment is as follows: Loading and Picking: The medical mold 5 containing medical devices is conveyed by the loading conveyor belt 3 to the receiving position of the floating transfer group 2. After the sensor detects that the mold 5 has arrived, the lifting cylinder 22 is activated, pushing the floating transfer group 2 upward. The floating block 241 and the upper ball bearing 247 contact and lift the mold 5, causing it to detach from the conveyor belt.

[0032] Pushing and Adaptive Alignment: The push cylinder 25 drives the support block 24 and the mold 5 on it to move towards the loading position A of the horizontal turntable 11. The constricted inclined block 51 on the mold 5 first inserts into the guide block slot 13 of the loading position A. Under the guidance of the inclined block, if there is a position or angle deviation of the mold, the resulting guiding force will be transmitted to the floating block 241 through the mold 5. The floating block 241 overcomes the elastic force of the compression spring 246 and makes a small translation and rotation within the slot of the support block 24 through the lower ball 242, thereby adaptively adjusting the position and angle of the mold 5 until it is precisely aligned and enters the support block slot 14.

[0033] Placement and Fixing: Once mold 5 is precisely in place, lifting cylinder 22 descends, support block 24 and floating block 241 move downwards, and mold 5 is placed on the loading position A of horizontal turntable 11. Subsequently, support block 24 retracts. The control system activates the negative pressure adsorption of loading position A to fix mold 5 in place.

[0034] Processing flow: Rotary motor 12 drives horizontal turntable 11 to rotate, sequentially sending mold 5 to processing station B, inspection station C, and unloading station D. Femtosecond laser processing is completed at processing station B, and online quality inspection is performed at inspection station C.

[0035] Material unloading: After mold 5 reaches the unloading position D, the negative pressure is released. It can be removed from the unloading position D by a robot (not shown in the figure, which is conventional technology in this field) or manually, completing one processing cycle.

[0036] Example 2: The main difference between this embodiment and Embodiment 1 is that it also includes a complete and symmetrical feeding system.

[0037] Specifically, see Figure 1 This embodiment also includes a feeding conveyor belt 4. The feeding conveyor belt 4 is located on the feeding position D side of the laser worktable 1. The feeding conveyor belt 3 and the feeding conveyor belt 4 have the same structure, both including two sets of conveyor belts arranged side by side. Similar to the feeding end, a feeding floating conveyor group 2b with the same structure is also provided between the two sets of feeding conveyor belts 4.

[0038] The structure, composition and working principle of the unloading floating transmission group 2b are exactly the same as those of the loading floating transmission group 2a described in Embodiment 1. It also includes a base frame, lifting cylinder, support rail, support block, push cylinder and floating adjustment mechanism in the support block.

[0039] The complete workflow of this embodiment is based on that of embodiment 1, with the material unloading process being automated: The feeding, processing, and testing process is exactly the same as steps 1-4 in Example 1.

[0040] Automated unloading: After the finished mold 5 rotates to the unloading position D with the horizontal turntable 11, the control system closes the negative pressure adsorption valve at that position. Subsequently, the unloading floating conveyor group 2b starts: Its lifting cylinder drives the support block to rise, lifting and picking up the mold 5 on the material drop position D from below.

[0041] The push cylinder drives the support block to move away from the horizontal turntable 11, smoothly transferring the mold 5 to the center of the two belts of the unloading conveyor belt 4.

[0042] The lifting cylinder descends, placing mold 5 onto the unloading conveyor belt 4.

[0043] The support block returns to its original position, the unloading conveyor belt 4 starts, and sends the processed mold 5 out of the tooling area, completing the automated unloading.

[0044] The beneficial effects of this embodiment are as follows: By adding a symmetrical unloading conveyor belt and an unloading floating transmission group to the basis of embodiment 1, the entire process from loading to unloading is fully automated and closed-loop. The unloading process also adopts a high-precision floating transmission mechanism to ensure that the mold is transferred smoothly and accurately from the worktable to the conveyor belt, avoiding the risk of collision or contamination that may be caused by manual handling, and further improving the automation level and overall efficiency of the production line.

[0045] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A femtosecond laser processing positioning fixture for medical molds, characterized in that, include: Laser worktable (1), wherein the laser worktable (1) is a horizontal turntable (11), and at least one set of workstations for positioning medical molds (5) are distributed circumferentially on its horizontal platform surface; The feeding conveyor belt (3) is used to transport the medical mold (5) to a side close to the laser worktable (1); The floating transport group (2) is located between the end of the feeding conveyor belt (3) and the laser worktable (1) to receive the medical mold (5) from the feeding conveyor belt (3), and after adaptive floating adjustment of its position and angle, it moves and positions the medical mold (5) to the work position of the laser worktable (1).

2. The femtosecond laser processing positioning fixture for medical molds according to claim 1, characterized in that: The horizontal turntable (11) has four sets of workstations evenly distributed circumferentially on its horizontal platform surface, which are defined as loading position (A), processing position (B), detection position (C) and unloading position (D). The horizontal turntable (11) is provided with an external gear ring around its periphery, and is driven by a rotary motor (12) to perform rotational indexing. Each workstation is provided with a set of support block slots (14). The support block slots (14) are surrounded by multiple negative pressure adsorption holes (15). The negative pressure adsorption holes (15) are connected to the negative pressure fan through independent adsorption pipelines. The adsorption pipelines are equipped with controlled solenoid valves.

3. The femtosecond laser processing positioning fixture for medical molds according to claim 2, characterized in that: The adsorption pipeline includes an adsorption chamber, an adsorption tube (16), and a central suction tube (17) corresponding to each workstation. The bottom of the negative pressure adsorption hole (15) of each workstation is connected to an independent adsorption chamber. Each adsorption chamber is connected to the central suction pipe (17) located at the center of the horizontal turntable (11) through an adsorption pipe (16) equipped with the solenoid valve. The central suction pipe (17) is connected to the negative pressure fan through a rotary joint.

4. The femtosecond laser processing positioning fixture for medical molds according to claim 1, characterized in that, The floating transport group (2) includes: Base frame (21); A lifting cylinder (22) is connected to the base frame (21) at its driving end, and is used to drive the base frame (21) to lift. The support rail (23) is horizontally installed on the base frame (21); The support block (24) is slidably mounted on the support rail (23); A push cylinder (25) is connected to the support block (24) at its driving end, and is used to drive the support block (24) to slide along the support rail (23); The top side of the support block (24) is provided with a floating block (241) for supporting the medical mold (5).

5. The femtosecond laser processing positioning fixture for medical molds according to claim 4, characterized in that: The top side of the support block (24) is also provided with a plurality of upper balls (247), the top of the upper balls (247) being flush with the top side plane of the floating block (241).

6. The femtosecond laser processing positioning fixture for medical molds according to claim 4 or 5, characterized in that: The support block (24) has a slot, and the floating block (241) is a cylindrical block and is accommodated in the slot; The bottom side of the floating block (241) is provided with a lower ball bearing (242), and the lower ball bearing (242) forms a rolling contact with the bottom of the groove. The floating block (241) is provided with multiple pairs of limiting blocks (243) on its circumferential side. An adjusting rod (244) corresponding to each pair of limiting blocks (243) is also inserted into the support block (24). One end of the adjusting rod (244) is provided with a ball head (245) that abuts against the side of the floating block (241), and the other end abuts against a compression spring (246).

7. The femtosecond laser processing positioning fixture for medical molds according to claim 6, characterized in that: The floating block (241) can be adjusted by translation and rotation within the range defined by the slot under the combined action of the abutting force applied by the compression spring (246) through the ball head (245), the rolling support of the lower ball (242), and the limiting action of the limiting block (243).

8. The femtosecond laser processing positioning fixture for medical molds according to claim 1, characterized in that: The medical mold (5) has a set of constricted inclined blocks (51) on one side near the laser worktable (1). Each station of the laser worktable (1) is provided with a set of guide block slots (13) for docking and guiding with the constricted inclined block (51).

9. The femtosecond laser processing positioning fixture for medical molds according to claim 1, characterized in that, Also includes: The unloading conveyor belt (4) is located on the unloading position (D) side of the laser worktable (1) and is used to send out the processed medical mold (5). It and the loading conveyor belt (3) are the same two sets of conveyor belts. A floating conveyor group is also provided between the two sets of conveyor belts of the unloading conveyor belt (4) to transport the medical mold (5) on the unloading position (D) to the two sets of conveyor belts.

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