A cutting head anti-collision protection structure of a laser cutting machine

Abstract

The application discloses a cutting head anti-collision protection structure of a laser cutting machine, which comprises a fixed seat, a floating seat, a mechanical spring buffer assembly and a piezoelectric ceramic collision detection assembly. The fixed seat is installed on a Z-axis movement mechanism of the laser cutting machine, the floating seat is movably connected below the fixed seat through the mechanical spring buffer assembly, and a laser cutting head body is installed at the bottom of the floating seat. The piezoelectric ceramic collision detection assembly is arranged between the fixed seat and the floating seat and is electrically connected with a control system of the laser cutting machine. When the cutting head collides, the floating seat generates a floating displacement relative to the fixed seat, the mechanical spring buffer assembly absorbs impact energy, and the piezoelectric ceramic collision detection assembly senses the collision in real time and outputs a trigger signal to the control system, so that rapid shutdown protection is realized. The application has the functions of mechanical buffering and electrical signal triggering, is fast in response and high in reliability, and can effectively prevent the cutting head from being damaged due to collision.

Description

Technical Field

[0001] This invention relates to the field of laser cutting technology, and in particular to a collision protection structure for the cutting head of a laser cutting machine. Background Technology

[0002] Laser cutting technology, with its advantages of high cutting precision, small heat-affected zone, and high processing efficiency, has been widely used in industrial fields such as sheet metal processing, automobile manufacturing, and aerospace. As the core execution component of laser cutting equipment, the laser cutting head integrates precision components such as precision optical lenses and capacitive height sensors, and must maintain a precise gap of micrometers with the workpiece surface during the cutting process.

[0003] In actual processing, due to factors such as sheet deformation and warping, tipping of cutting residue, control program deviations, or tool setting errors, the cutting head often collides unexpectedly with the workpiece or worktable. Once a collision occurs, not only will the expensive cutting head itself be damaged, but hidden damage such as optical lens misalignment and ceramic sealing ring breakage will also affect the subsequent cutting quality, and may even cause the entire batch of test pieces to be scrapped.

[0004] Currently, existing anti-collision devices have the following shortcomings: First, relying solely on mechanical spring buffer structures, while capable of absorbing some collision energy, lacks a rapid electrical signal triggering mechanism, making it impossible to stop the machine in time at the moment of collision. The cutting process continues, and the post-collision oscillation causes the laser beam to disperse, resulting in product burnt edges and scrap. Second, relying on capacitive or photoelectric displacement sensors for distance detection cannot achieve collision sensing. Third, the solution of attaching a piezoelectric film to the outside of the cutting head is prone to performance degradation and decreased collision sensitivity in cutting environments with severe dust and oil contamination. Furthermore, the soft collision layer has a limited buffer distance, posing a dual risk of sensor and cutting head damage in high-energy collision scenarios.

[0005] Therefore, there is an urgent need for a collision protection structure that can buffer and absorb collision energy and trigger collision electrical signals, so that it can both physically buffer the impact in the event of an accidental collision and quickly send a stop command to the control system to avoid interruption of large-scale sample processing tasks due to collision. Summary of the Invention

[0006] The present invention aims to solve the technical problem that it is difficult to balance the response speed and buffer protection of laser cutting head anti-collision devices in the prior art, and provides a cutting head anti-collision protection structure that combines mechanical spring buffering and piezoelectric ceramic sensor collision detection.

[0007] To achieve the above objectives, the present invention provides the following technical solution: A collision protection structure for the cutting head of a laser cutting machine includes: a fixed base, a floating base, a mechanical spring buffer assembly, and a piezoelectric ceramic collision detection assembly. The fixed base is mounted on the Z-axis motion mechanism of the laser cutting machine. The floating base is movably connected to the lower part of the fixed base through the mechanical spring buffer assembly. The laser cutting head body is mounted on the bottom of the floating base. When the laser cutting head is impacted, the floating base undergoes a floating displacement relative to the fixed base. The piezoelectric ceramic collision detection component is disposed between the fixed base and the floating base, and is electrically connected to the control system of the laser cutting machine.

[0008] Optionally, the fixing base includes a first housing, which is in the shape of a square tube, with a cover detachably connected to its top end and a first limiting ring provided at its bottom end. A first optical fiber penetration hole is provided in the center of the cover.

[0009] Optionally, the floating seat includes a second housing, which is slidably connected to the first housing. The top of the second housing is provided with a second limiting ring corresponding to the first limiting ring, and the bottom center of the second housing is provided with a second optical fiber penetration hole, which is located directly below the first optical fiber penetration hole.

[0010] Optionally, the mechanical spring buffer assembly includes a plurality of first spring guide rods and a first compression spring. The bottom end of the first spring guide rod is fixed on the floating seat, and the top end extends into the first spring guide cylinder on the fixed seat. The first compression spring is sleeved on the first spring guide rod and the first spring guide cylinder, and its two ends abut against the fixed seat and the floating seat, respectively.

[0011] Optionally, the mechanical spring buffer assembly further includes a first preload cylinder and a second preload cylinder. The first preload cylinder is mounted on the floating seat, and the second preload cylinder is mounted on the fixed seat and faces the first preload cylinder. The second preload cylinder has an internal thread, and the limiting bolt passes through the first preload cylinder on the floating seat and is threadedly connected to the second preload cylinder on the fixed seat.

[0012] Optionally, the piezoelectric ceramic collision detection assembly includes a piezoelectric ceramic sensor, a signal processing module, a first sleeve, a second sleeve, a slide bar, a cap, a second compression spring, and a third compression spring. The first sleeve is mounted on the fixed base, the second sleeve is mounted on the floating base and is directly opposite the first sleeve, and the piezoelectric ceramic sensor is mounted inside the first sleeve with its sensing surface facing the cap; The slide rod is slidably connected to the second sleeve, and the cap is installed at the end of the slide rod and slidably connected inside the first sleeve. The second compression spring is disposed inside the first sleeve and sleeved on the piezoelectric ceramic sensor, with its two ends abutting against the fixed base and the cap, respectively; The third compression spring is sleeved on the second sleeve and the slide rod, with its two ends abutting against the floating seat and the cap, respectively. The input terminal of the signal processing module is electrically connected to the piezoelectric ceramic sensor, and the output terminal is electrically connected to the control system of the laser cutting machine.

[0013] Optionally, the signal processing module includes a signal amplification circuit and a comparison circuit; the weak charge signal generated by the piezoelectric ceramic sensor is amplified by the signal amplification circuit and then input to the comparison circuit. The comparison circuit compares the amplified signal with a preset threshold voltage. When the signal exceeds the threshold, it outputs a high-level trigger signal to the control system of the laser cutting machine.

[0014] Optionally, a third optical fiber penetration hole is provided on the side wall of the second housing.

[0015] Compared with the prior art, the beneficial technical effects of the present invention are as follows: Dual protection mechanism: The mechanical spring buffer component absorbs the kinetic energy of the collision, while the piezoelectric ceramic collision detection component triggers an electrical signal at the moment of collision, providing both physical buffering and electrical shutdown protection, significantly reducing the risk of damage to the cutting head.

[0016] Fast response speed: The piezoelectric ceramic sensor has high sensitivity and fast response characteristics. The weak charge signal generated by the collision is processed by the signal amplification and comparison circuit and can output a trigger signal within milliseconds, so that the control system can immediately stop the cutting action and avoid secondary damage or product burn-out due to delayed shutdown.

[0017] Compact structure, adaptable to harsh environments: The piezoelectric ceramic sensor is built into the sleeve structure, isolated from external dust and oil, making it less susceptible to interference from the cutting environment and ensuring stable performance over long-term use. The overall structure is integrated between the fixed base and the floating base, without increasing the external volume of the cutting head.

[0018] Adjustable preload: The initial preload of the mechanical spring buffer assembly can be adjusted by the cooperation of the first preload cylinder, the second preload cylinder and the limit bolt, to adapt to cutting heads of different weights or dynamic characteristics and improve the adaptability of collision protection.

[0019] Low maintenance cost: The modular design of each component allows for the independent replacement of easily damaged parts such as springs and piezoelectric ceramic sensors, reducing the difficulty and cost of later maintenance. Attached Figure Description

[0020] The present invention will be further described below with reference to the accompanying drawings.

[0021] Figure 1 This is a schematic diagram of the anti-collision protection structure of the cutting head of the laser cutting machine of the present invention; Figure 2 This is an exploded view of the anti-collision protection structure of the laser cutting machine's cutting head according to the present invention; Figure 3 This is a schematic diagram of the first housing structure of the present invention; Figure 4 This is a schematic diagram of the cover structure of the present invention; Figure 5 This is a front view of the cover of the present invention; Figure 6 This is a cross-sectional view of the cover of the present invention; Figure 7 This is a schematic diagram of the second housing structure of the present invention; Figure 8 This is a schematic diagram showing the connection between the slide bar and the cap of the present invention.

[0022] Explanation of reference numerals in the attached drawings: 1. Fixing base; 11. First housing; 12. Cover; 13. First limiting ring; 14. First optical fiber penetration hole; 2. Floating seat; 21. Second housing; 22. Second limiting ring; 23. Second optical fiber penetration hole; 3. Mechanical spring buffer assembly; 31. First spring guide rod; 32. First compression spring; 33. First spring guide cylinder; 34. First preload cylinder; 35. Second preload cylinder; 36. Limit bolt; 4. Piezoelectric ceramic collision detection component; 41. Piezoelectric ceramic sensor; 42. Signal processing module; 43. First sleeve; 44. Second sleeve; 45. Slide rod; 46. Cap; 47. Second compression spring; 48. Third compression spring. Detailed Implementation

[0023] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present 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 used to explain the present invention and are not intended to limit the present invention.

[0024] like Figure 1-8 As shown, this embodiment provides a collision protection structure for the cutting head of a laser cutting machine, including: a fixed base 1, a floating base 2, a mechanical spring buffer assembly 3, and a piezoelectric ceramic collision detection assembly 4. The fixed base 1 is installed on the Z-axis motion mechanism of the laser cutting machine. The floating base 2 is movably connected to the lower part of the fixed base 1 through the mechanical spring buffer assembly 3. The laser cutting head body is installed at the bottom of the floating base 2. When the laser cutting head is impacted, the floating base 2 generates a floating displacement relative to the fixed base 1. The piezoelectric ceramic collision detection component 4 is disposed between the fixed base 1 and the floating base 2, and is electrically connected to the control system of the laser cutting machine.

[0025] Specifically, the fixing base 1 includes a first housing 11, which is in the shape of a square tube. A cover 12 is detachably connected to its top end, and a first limiting ring 13 is provided at its bottom end. A first optical fiber penetration hole 14 is provided in the center of the cover 12.

[0026] Specifically, the floating seat 2 includes a second housing 21, which is slidably connected to the first housing 11. The top of the second housing 21 is provided with a second limiting ring 22 corresponding to the first limiting ring 13. The bottom center of the second housing 21 is provided with a second optical fiber penetration reserved hole 23, which is located directly below the first optical fiber penetration reserved hole 14.

[0027] Specifically, the mechanical spring buffer assembly 3 includes a plurality of first spring guide rods 31 and first compression springs 32. The bottom end of the first spring guide rod 31 is fixed on the floating seat 2, and the top end extends into the first spring guide cylinder 33 on the fixed seat 1. The first compression spring 32 is sleeved on the first spring guide rod 31 and the first spring guide cylinder 33, and its two ends abut against the fixed seat 1 and the floating seat 2 respectively.

[0028] Specifically, the mechanical spring buffer assembly 3 further includes a first preload cylinder 34 and a second preload cylinder 35. The first preload cylinder 34 is mounted on the floating seat 2, and the second preload cylinder 35 is mounted on the fixed seat 1 and faces the first preload cylinder 34. The second preload cylinder 35 has an internal thread. The limiting bolt 36 passes through the first preload cylinder 34 on the floating seat 2 and is threadedly connected to the second preload cylinder 35 on the fixed seat 1.

[0029] Specifically, the piezoelectric ceramic collision detection assembly 4 includes a piezoelectric ceramic sensor 41, a signal processing module 42, a first sleeve 43, a second sleeve 44, a slide rod 45, a cap 46, a second compression spring 47, and a third compression spring 48. The first sleeve 43 is mounted on the fixed base 1, the second sleeve 44 is mounted on the floating base 2 and is directly opposite the first sleeve 43, and the piezoelectric ceramic sensor 41 is mounted inside the first sleeve 43 with its sensing surface facing the cap 46. The slide rod 45 is slidably connected to the second sleeve 44, and the cap 46 is installed at the end of the slide rod 45 and slidably connected inside the first sleeve 43. The second compression spring 47 is disposed inside the first sleeve 43 and sleeved on the piezoelectric ceramic sensor 41, with its two ends abutting against the fixed base 1 and the cap 46 respectively; The third compression spring 48 is sleeved on the second sleeve 44 and the slide rod 45, with its two ends abutting against the floating seat 2 and the cap 46 respectively. The input terminal of the signal processing module 42 is electrically connected to the piezoelectric ceramic sensor 41, and the output terminal is electrically connected to the control system of the laser cutting machine.

[0030] Initially, the cap 46 is located near the piezoelectric ceramic sensor 41. Upon collision, the floating seat 2 floats relative to the fixed seat 1, and the third compression spring 48 drives the cap 46 to press against the piezoelectric ceramic sensor 41. The piezoelectric ceramic sensor 41 generates an electrical signal under pressure and transmits it to the signal processing module 42. After the collision, the floating seat 2 resets, and the second compression spring 47 pushes the cap 46 off the piezoelectric ceramic sensor 41 to reset it, thus preventing the piezoelectric ceramic sensor 41 from being subjected to long-term pressure, which could lead to fatigue accumulation and performance degradation.

[0031] The cap 46 is driven by the third compression spring 48 to squeeze the piezoelectric ceramic sensor 41. The pressure of the cap 46 can be kept below the compressive strength of the piezoelectric ceramic by adjusting the elasticity of the third compression spring 48, thus preventing it from being crushed.

[0032] At the moment of impact, the third compression spring 48 is compressed first to generate buffer, and almost simultaneously the spring force acts directly on the piezoelectric ceramic sensor 41, instantly generating a high-intensity impact electrical signal. This direct coupling of "spring-piezoelectric" forms a perfect timing sequence of "buffering first, then triggering", resulting in a fast response speed.

[0033] Specifically, the signal processing module 42 includes a signal amplification circuit and a comparison circuit; the weak charge signal generated by the piezoelectric ceramic sensor 41 is amplified by the signal amplification circuit and then input to the comparison circuit. The comparison circuit compares the amplified signal with a preset threshold voltage. When the signal exceeds the threshold, it outputs a high-level trigger signal to the control system of the laser cutting machine.

[0034] Specifically, a third optical fiber penetration hole is provided on the side wall of the second housing 21.

[0035] The present invention discloses a collision protection structure for the cutting head of a laser cutting machine, the working principle of which is as follows: In normal operation of the laser cutting machine, the fixed base 1 is mounted on the Z-axis motion mechanism, and the floating base 2 is suspended below the fixed base 1 by a mechanical spring buffer assembly 3. The laser cutting head body is fixed to the bottom of the floating base 2. At this time, the cap 46 in the piezoelectric ceramic collision detection assembly 4 maintains a small gap or slight contact with the piezoelectric ceramic sensor 41 under the action of the second compression spring 47, but does not generate an effective trigger signal. The output of the piezoelectric ceramic sensor 41 is in a low-level or zero-level state.

[0036] When the laser cutting head accidentally collides with the workpiece or table during processing, the cutting head body experiences an upward impact force, causing the floating seat 2 to float upward relative to the fixed seat 1. At this time: Mechanical buffering process: The first compression spring 32 in the mechanical spring buffer assembly 3 is further compressed to absorb the kinetic energy generated by the collision, reduce the transmission of the impact to the fixed seat 1 and the Z-axis motion mechanism, and play a physical buffering protection role.

[0037] Electrical signal triggering process: When the floating seat 2 moves upward, the third compression spring 48 drives the cap 46 to squeeze the piezoelectric ceramic sensor 41. The piezoelectric ceramic sensor 41 is subjected to instantaneous compression, and based on the piezoelectric effect, a weak charge signal proportional to the impact force is generated at its two poles.

[0038] The weak charge signal is amplified by the signal amplification circuit in the signal processing module 42 and then compared with a preset threshold voltage by the comparison circuit. When the amplified signal exceeds the threshold, the comparison circuit outputs a high-level trigger signal to the control system of the laser cutting machine. Upon receiving the trigger signal, the control system immediately executes an emergency stop command, cutting off the laser output and stopping the Z-axis and XY-axis movements, thereby preventing further damage to the cutting head or burnt edges on the workpiece.

[0039] After the collision, the operator manually or automatically resets the floating seat 2. At this time, the first compression spring 32 pushes the floating seat 2 downward to reset, and the second compression spring 47 pushes the cap 46 away from the piezoelectric ceramic sensor 41, restoring it to its initial pressure-free state and preventing the piezoelectric ceramic sensor 41 from being degraded or damaged due to long-term pressure. The signal processing module 42 output returns to a low level, and the device can re-enter standby or reset working state.

[0040] In addition, by adjusting the cooperation between the limiting bolt 36 and the first pre-tightening cylinder 34 and the second pre-tightening cylinder 35, the initial pre-tightening force of the first compression spring 32 can be changed, thereby adjusting the initial floating sensitivity of the floating seat 2 to adapt to cutting heads of different weights or dynamic characteristics, and improve the adaptability and reliability of collision protection.

[0041] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0042] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A collision protection structure for the cutting head of a laser cutting machine, characterized in that, include: The laser cutting head comprises a fixed base (1), a floating base (2), a mechanical spring buffer assembly (3), and a piezoelectric ceramic collision detection assembly (4). The fixed base (1) is mounted on the Z-axis motion mechanism of the laser cutting machine. The floating base (2) is movably connected to the bottom of the fixed base (1) via the mechanical spring buffer assembly (3). The laser cutting head body is mounted on the bottom of the floating base (2). When the laser cutting head is impacted, the floating base (2) generates a floating displacement relative to the fixed base (1). The piezoelectric ceramic collision detection component (4) is disposed between the fixed base (1) and the floating base (2) and is electrically connected to the control system of the laser cutting machine.

2. The anti-collision protection structure for the cutting head of a laser cutting machine according to claim 1, characterized in that: The fixing base (1) includes a first housing (11), which is in the shape of a square tube. A cover (12) is detachably connected to its top end, and a first limiting ring (13) is provided at its bottom end. A first optical fiber penetration reserved hole (14) is opened in the center of the cover (12).

3. The anti-collision protection structure for the cutting head of a laser cutting machine according to claim 2, characterized in that: The floating seat (2) includes a second housing (21), which is slidably connected to the first housing (11). The top of the second housing (21) is provided with a second limiting ring (22) corresponding to the first limiting ring (13). The bottom center of the second housing (21) is provided with a second optical fiber penetration reserved hole (23), which is located directly below the first optical fiber penetration reserved hole (14).

4. The anti-collision protection structure for the cutting head of the laser cutting machine according to claim 3, characterized in that: The mechanical spring buffer assembly (3) includes several first spring guide rods (31) and first compression springs (32). The bottom end of the first spring guide rod (31) is fixed on the floating seat (2), and the top end extends into the first spring guide cylinder (33) on the fixed seat (1). The first compression spring (32) is sleeved on the first spring guide rod (31) and the first spring guide cylinder (33), and its two ends abut against the fixed seat (1) and the floating seat (2) respectively.

5. The anti-collision protection structure for the cutting head of a laser cutting machine according to claim 3, characterized in that: The mechanical spring buffer assembly (3) further includes a first preload cylinder (34) and a second preload cylinder (35). The first preload cylinder (34) is mounted on the floating seat (2), and the second preload cylinder (35) is mounted on the fixed seat (1) and is directly opposite the first preload cylinder (34). The second preload cylinder (35) has an internal thread. The limiting bolt (36) passes through the first preload cylinder (34) on the floating seat (2) and is threadedly connected to the second preload cylinder (35) on the fixed seat (1).

6. The anti-collision protection structure for the cutting head of a laser cutting machine according to claim 1, characterized in that: The piezoelectric ceramic collision detection assembly (4) includes a piezoelectric ceramic sensor (41), a signal processing module (42), a first sleeve (43), a second sleeve (44), a slide bar (45), a cap (46), a second compression spring (47), and a third compression spring (48). The first sleeve (43) is mounted on the fixed base (1), the second sleeve (44) is mounted on the floating base (2) and faces the first sleeve (43), and the piezoelectric ceramic sensor (41) is mounted inside the first sleeve (43) with its sensing surface facing the cap (46). The slide rod (45) is slidably connected to the second sleeve (44), and the cap (46) is installed at the end of the slide rod (45) and slidably connected inside the first sleeve (43). The second compression spring (47) is disposed inside the first sleeve (43) and sleeved on the piezoelectric ceramic sensor (41), with its two ends abutting against the fixed base (1) and the cap (46) respectively; The third compression spring (48) is sleeved on the second sleeve (44) and the slide rod (45), with its two ends abutting against the floating seat (2) and the cap (46) respectively; The input terminal of the signal processing module (42) is electrically connected to the piezoelectric ceramic sensor (41), and the output terminal is electrically connected to the control system of the laser cutting machine.

7. The anti-collision protection structure for the cutting head of a laser cutting machine according to claim 6, characterized in that: The signal processing module (42) includes a signal amplification circuit and a comparison circuit. The weak charge signal generated by the piezoelectric ceramic sensor (41) is amplified by the signal amplification circuit and then input to the comparison circuit. The comparison circuit compares the amplified signal with a preset threshold voltage. When the signal exceeds the threshold, it outputs a high-level trigger signal to the control system of the laser cutting machine.

8. The anti-collision protection structure for the cutting head of the laser cutting machine according to claim 3, characterized in that: The second housing (21) has a third optical fiber penetration hole on its side wall.

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