Portable laser internal engraving machine

Abstract

The application relates to the technical field of laser inner engraving machines, in particular to a portable laser inner engraving machine which comprises a table body installed in the inner engraving machine body, a pressure bearing unit installed on the top of the table body, the pressure bearing unit comprising a carrier used for bearing a workpiece, the carrier sinking with the weight of the workpiece when the workpiece is placed, a transmission unit comprising a transmission bar, the transmission bar moving towards a first direction when the carrier sinks, the transmission bar moving towards a second direction when the workpiece is taken off from the top of the carrier, and at least four clamping units having a clamping state and a release state, when the workpiece is placed on the pressure bearing unit, the pressure bearing unit moving downwards under the action of gravity when the transmission bar moves towards the first direction, the clamping unit being driven, the clamping unit moving towards the center synchronously and having the same stroke, the workpiece being pushed to the center of the workbench and clamped, the center of the workpiece being ensured to coincide with a laser light path, the engraving deviation and the asymmetric pattern being avoided, and the engraving precision being improved.

Description

Technical Field

[0001] This invention relates to the field of laser engraving machine technology, specifically a portable laser engraving machine. Background Technology

[0002] Laser engraving machines utilize laser beams to create a matrix of dots inside transparent materials such as glass and crystal, achieving three-dimensional engraving. They are widely used in craft processing and personalized customization. Traditional desktop engraving machines are bulky and inconvenient to move, failing to meet the needs of outdoor on-site and door-to-door services. Portable engraving machines have emerged to address this need. Their core requirements are to achieve lightweight and miniaturization while maintaining engraving accuracy, facilitating portability and deployment, and ensuring convenient operation and efficient and reliable workpiece positioning. However, current development is limited by unreasonable workpiece positioning and clamping structures, making it difficult to balance portability and engraving accuracy.

[0003] The core design principle of portable internal engraving machines is lightweighting and miniaturization to achieve convenient portability and on-site deployment. However, traditional workpiece fixing structures are often large and complex, increasing the overall weight and size of the equipment and conflicting with the portability requirement. In order to minimize the size and weight of the equipment, most existing products have abandoned the workpiece fixing structure, resulting in the workpiece not being stably positioned after placement, easily causing offset and skew, and causing the workpiece center to not coincide with the laser beam path, seriously affecting the engraving accuracy. Summary of the Invention

[0004] The purpose of this invention is to provide a portable laser engraving machine to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A portable laser engraving machine, comprising:

[0007] The platform is installed inside the engraving machine body;

[0008] A pressure-bearing unit is installed on the top of the platform. The pressure-bearing unit includes a carrier for supporting the workpiece, and the carrier sinks with the weight of the workpiece when it is placed.

[0009] A transmission unit includes a transmission bar, which is driven to move in a first direction when the carrier sinks, and moves in a second direction when the workpiece is removed from the top of the carrier.

[0010] At least four clamping units are provided, with clamping and releasing states. When the transmission bar moves in the first direction, the clamping units move synchronously in the direction of the carrier and fix the workpiece at the center of the platform. When the transmission bar moves in the second direction, the clamping units are switched to the releasing state and the workpiece is stopped from being fixed. The clamping unit includes a clamping plate. When clamping, the transmission bar is locked by the clamping plate to avoid excessive clamping force.

[0011] Preferably, the top of the platform is provided with a first cavity, the pressure-bearing unit is installed in the first cavity and allows the pressure-bearing unit to move up and down along the first cavity, the pressure-bearing unit also includes a transmission block, the transmission block is disposed at the bottom of the carrier, one side of the transmission block and one end of the transmission bar form a mutually adapted inclined surface, the top of the transmission bar is provided with a rack and meshes with a gear, and the bottom of the clamping unit is provided with a rack and meshes with a gear.

[0012] Preferably, the clamping unit has an internal cavity, the clamping plate is installed at one end of the cavity and connected to the inner wall of the cavity by a spring, a brake strip is fixedly connected to one side of the clamping plate, a brake block is connected to the bottom of the brake strip by a spring, the gear also includes a rotating shaft, the gear is connected to the inner cavity of the platform through the rotating shaft, a brake ring is provided on the outer side of the rotating shaft, and a groove is provided at the bottom of the clamping unit, allowing the brake block to pass through the groove and contact the brake ring.

[0013] Preferably, when the transmission block moves toward the bottom wall of the first groove, the inclined plane causes the transmission bar to move toward the first direction and drives the gear to rotate, causing the clamping unit to move toward the second direction. The direction where the pressure-bearing unit is located is set as the second direction, and the opposite direction is set as the first direction.

[0014] Preferably, the bottom of the carrier is provided with a disassembly unit, which includes a first displacement plate, a support shaft, a second displacement plate, a limiting plate, and a positioning ring. The top of the first displacement plate is provided with a support shaft, and the top of the support shaft is provided with a second displacement plate. When the pressure unit carries the workpiece, the second displacement plate moves toward the first displacement plate and compresses the support shaft. The corresponding surfaces of the second displacement plate and the first displacement plate are provided with mutually misaligned displacement blocks.

[0015] Preferably, a lifting shaft is provided on the top of the second displacement plate, a limiting plate is provided on the outer side of the lifting shaft, a hole is provided on the bottom wall of the first groove, a positioning ring is fixedly installed in the hole, the positioning ring is provided with a fitting groove, and the inner wall of the fitting groove is adapted to the outer edge of the second displacement plate.

[0016] Preferably, the brake block has a pawl, and the outer periphery of the brake ring is provided with ratchet teeth that cooperate with the pawl. Both the pawl and the ratchet teeth are structures that combine inclined guide surfaces and stop surfaces. When the brake block and the brake ring are in contact, the pawl and the ratchet teeth form a unidirectional constraint, allowing the brake ring to rotate only in the second direction, so that the shaft and gear can only rotate in the second direction.

[0017] Preferably, the bottom of the transmission bar has a groove, and a reset seat is provided in the groove. The reset seat is connected to the inner wall of the groove by a spring.

[0018] Preferably, a disc spring is also provided in the first groove cavity, the preload of the disc spring can be adjusted, a pad is provided at the bottom end of the disc spring, and a bolt is provided at the bottom of the platform.

[0019] Preferably, a second groove is provided on the inner side of the platform, and the clamping unit is disposed in the second groove. When the four clamping units move synchronously toward the pressure-bearing unit and clamp and fix the workpiece placed on the pressure-bearing unit, the clamping unit is in a clamping state. When the four clamping units move toward the inner cavity of the second groove and stop clamping the workpiece, the clamping unit is in a releasing state.

[0020] Compared with the prior art, the beneficial effects of the present invention are:

[0021] 1. In this invention, by setting a pressure-bearing unit on the worktable, when the workpiece is placed on the pressure-bearing unit, the pressure-bearing unit moves downward under gravity, which drives the transmission unit and the clamping unit to move synchronously towards the center with the same stroke, pushing the workpiece to the center of the worktable and clamping it, ensuring that the center of the workpiece coincides with the laser optical path, avoiding engraving offset and pattern asymmetry, and improving engraving accuracy.

[0022] 2. In addition, by setting a braking unit on the clamping unit, when the clamping unit finishes fixing the workpiece, the braking unit locks the transmission unit, fixing the position of the clamping unit and stopping the pressure unit from moving down, thus avoiding the problem of excessive clamping force and easy damage to the workpiece. The clamping force is precisely controlled by the braking limit, taking into account both the workpiece clamping stability and safety, and is suitable for the engraving needs of fragile workpieces such as glass and crystal.

[0023] 3. Based on the above structure, by setting a reset unit at the bottom of the pressure unit, when the workpiece is placed, the pressure unit moves downward, driving the transmission unit to rotate and achieve centering and clamping of the workpiece. When the workpiece is removed, the pressure unit is pressed again, the reset unit drives the pressure unit to reset, and then drives the transmission unit to move in the opposite direction, so that the clamping unit returns to its original position and stops and is fixed, thus solving the problem of inconvenience in removing the workpiece after clamping. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0025] Figure 2 This is an exploded view of the overall structure of the platform in this invention;

[0026] Figure 3 This is a schematic diagram of the bottom structure of the platform in this invention;

[0027] Figure 4 This is a schematic diagram of the structure of the pressure-bearing unit and the clamping unit in this invention;

[0028] Figure 5 This is a schematic diagram of the cross-sectional structure of the transmission unit in this invention;

[0029] Figure 6 This is a schematic diagram of the contact portion between the brake ring and the brake block in this invention;

[0030] Figure 7 This is a schematic diagram of the planar structure of the brake ring and brake block in this invention;

[0031] Figure 8 This is a schematic diagram of the overall structure of the disassembly unit in this invention.

[0032] In the diagram: 100, platform; 110, bolt; 120, first cavity; 130, second cavity; 200, pressure-bearing unit; 210, carrier; 220, transmission block; 230, disc spring; 240, pad; 300, transmission unit; 310, transmission bar; 320, gear; 321, rotating shaft; 322, brake ring; 330, reset seat; 400, clamping unit; 410, clamping plate; 411, brake bar; 412, brake block; 500, disassembly unit; 510, first displacement plate; 520, support shaft; 530, second displacement plate; 540, limiting plate; 550, positioning ring; 551, fitting groove; 560, lifting shaft; 570, displacement block. Detailed Implementation

[0033] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0034] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0035] like Figures 1-2 The embodiment shown discloses a portable laser engraving machine, including a platform 100, a pressure-bearing unit 200, a transmission unit 300, and a clamping unit 400. The platform 100, the pressure-bearing unit 200, the transmission unit 300, and the clamping unit 400 are all installed in the machine body of the engraving machine.

[0036] like Figure 2As shown, the top of the platform 100 has a groove, and the center of the groove has a first cavity 120. The pressure-bearing unit 200 is installed in the first cavity 120 and is allowed to move up and down along the first cavity 120. The inner wall of the groove at the top of the platform 100 has four second cavities 130. Each second cavity 130 is equipped with a clamping unit 400. When the workpiece is placed on top of the pressure-bearing unit 200, the weight of the workpiece causes the pressure-bearing unit 200 to move downward. The transmission unit 300 is located inside the platform 100 and at the bottom of the pressure-bearing unit 200. When the pressure-bearing unit 200 moves downward, the transmission unit 300 drives the four clamping units 400 to clamp and fix the workpiece from four directions. The stroke of each clamping unit 400 is the same, fixing the workpiece at the center of the platform 100. After fixing, the clamping unit 400 is in the clamping state.

[0037] like Figure 4 As shown, the pressure-bearing unit 200 includes a carrier 210 and transmission blocks 220. Four transmission blocks 220 are arranged at the bottom of the carrier 210. The transmission unit 300 includes a transmission bar 310. The corresponding ends of the transmission bar 310 and the transmission blocks 220 are all configured with mutually adaptable inclined surfaces. That is, when the transmission block 220 moves downwards, under the action of the inclined surface, it pushes the transmission bar 310 to move in a first direction. The first direction is... Figure 4 In the direction indicated by the middle arrow, a rack is provided at the top of the transmission bar 310, and the rack meshes with a gear 320. The transmission bar 310 moves in the first direction, causing the gear 320 to rotate in the first direction. The bottom of the clamping unit 400 is provided with a rack, which meshes with the gear 320. The gear 320 rotates in the first direction, driving the clamping unit 400 to move in the second direction, that is, in the direction of the pressure unit 200. The four clamping units 400 converge towards the center simultaneously, fixing the workpiece at the center of the platform 100. The stroke of each clamping unit 400 is the same, so that the workpiece placed on the pressure unit 200 is fixed at the center position of the top of the platform 100.

[0038] In a more specific plan, continue as follows Figure 4As shown, a groove is provided at the bottom of the transmission bar 310, and a reset seat 330 is provided in the groove. The reset seat 330 is connected to the inner wall of the groove of the transmission bar 310 by a spring. When the transmission bar 310 moves in the first direction, the reset seat 330 moves in the first direction, and the spring is stretched and deformed. A disc spring 230 is also provided at the bottom of the carrier 210. When the carrier 210 moves downward due to the weight of the workpiece, the disc spring 230 is compressed and deformed. When the workpiece is removed from the top of the carrier 210, the disc spring 230 rebounds and drives the carrier 210 to move upward, and the transmission block 220 disengages from the transmission bar 310. The spring of the reset seat 330 rebounds and drives the transmission bar 310 to move in the second direction closer to the carrier 210. Through the meshing of the rack and pinion, the clamping unit 400 moves away from the carrier 210 and retracts into the second groove 130, completing the reset, which is convenient for the subsequent positioning and fixing of the workpiece.

[0039] In a more preferred embodiment, such as Figure 5 As shown, a cavity is provided on one side of the clamping unit 400, and a clamping plate 410 is connected to the cavity via a spring. When the clamping unit 400 clamps the workpiece, the clamping plate 410 contacts the workpiece, and under the action of the clamping force, it pushes the clamping plate 410 to move in the first direction. A brake strip 411 is fixedly connected to one side of the clamping plate 410. Figure 6 As shown, the bottom of the brake bar 411 is connected to the brake block 412 via a spring. The bottom of the clamping unit 400 has a groove for the brake block 412 to pass through. The clamping plate 410 moves in a first direction, pushing the brake bar 411 in the same direction. The brake bar 411 aligns the brake block 412 with the groove. Under the spring force, the brake block 412 passes through the groove and pops outward, protruding from the bottom of the clamping unit 400. The gear 320 also includes a rotating shaft 321. The 0 is connected to the inner cavity of the platform 100 via the rotating shaft 321. A brake ring 322 is provided on the outer side of the rotating shaft 321. When the brake block 412 protrudes from the bottom of the clamping unit 400, it contacts the brake ring 322, preventing the gear 320 from rotating in the first direction and preventing the clamping unit 400 from moving in the second direction. At the same time, the carrier 210 stops moving downward to avoid the workpiece being too heavy, which would cause the clamping unit 400 to continue moving in the second direction and continuously squeeze the outer side of the workpiece, resulting in damage to the outer side of the workpiece.

[0040] To prevent gear 320 from rotating in the first direction, such as Figure 7As shown, the brake block 412 has a pawl, and the outer periphery of the brake ring 322 is provided with ratchet teeth that cooperate with the pawl. Both the pawl and the ratchet teeth are structures that combine inclined guide surfaces and stop surfaces. When the brake block 412 and the brake ring 322 are in contact and engaged, the pawl and the ratchet teeth form a unidirectional constraint, allowing the brake ring 322 to rotate only in the second direction. This allows the rotating shaft 321 and the gear 320 to rotate only in the second direction. While avoiding continuous compression of the workpiece, since the brake ring 322 can rotate in the second direction, removing the workpiece at this time can return the clamping unit 400 to its original position, which is convenient for positioning and fixing subsequent workpieces.

[0041] like Figures 3-4 As shown, the preload of the disc spring 230 can be adjusted. A pad 240 is provided at the bottom of the disc spring 230. By moving the position of the pad 240, the overall length of the disc spring 230 can be adjusted, thereby changing the preload of the disc spring 230. When the workpiece weight is insufficient, the carrier 210 sinks too far, that is, the transmission block 220 drives the transmission bar 310 to move too far, resulting in the clamping unit 400 not moving to the designated position to clamp the workpiece. By adjusting the preload of the disc spring 230, the supporting force of the disc spring 230 on the carrier 210 is reduced, allowing the carrier 210 to sink a sufficient distance, and the clamping unit 400 clamps and fixes the workpiece. A bolt 110 is provided at the bottom of the platform 100. By rotating the bolt 110, the height of the pad 240 can be adjusted, thereby adjusting the preload of the disc spring 230.

[0042] like Figure 6 As shown, one side of the brake block 412 is set as an inclined surface. When the clamping unit 400 stops clamping the workpiece, the spring connected to the clamping plate 410 loses pressure and rebounds, causing the clamping plate 410 to move in the second direction, causing the brake bar 411 to move in the second direction back to its original position. Since one side of the brake block 412 is set as an inclined surface, when the brake bar 411 moves in the second direction, the brake block 412 is subjected to a pulling force in the second direction. Under the action of the inclined surface, the brake block 412 moves upward along the inner wall of the groove and leaves the outer edge of the brake ring 322. At this time, the gear 320 can rotate in the first direction to drive the clamping unit 400 to clamp and fix the subsequent workpiece.

[0043] During use, it was found that when the clamping unit 400 clamps the outside of the workpiece, under the action of the clamping force and the spring connected to the clamping plate 410, the workpiece is fixed by the four clamping units 400 at the same time under the action of the spring force, which makes it inconvenient to remove it from the table 100. Forcibly removing it can easily cause the surface of the workpiece to be scratched.

[0044] Therefore, in order to solve the above problems, such as Figure 4As shown, a disassembly unit 500 is also provided at the bottom of the carrier 210. When the workpiece is placed on top of the carrier 210, the carrier 210 moves downward. At this time, the disassembly unit 500 is compressed and its overall length is shortened. When the workpiece needs to be engraved and removed from the platform 100, the carrier 210 is pressed down again, causing the carrier 210 to move further downward, and the disassembly unit 500 is compressed again. After the workpiece is engraved, the carrier 210 is pressed again, driving the lifting shaft 560 to move further down, squeezing the second position plate 530 closer to the first position plate 510; the two sets of matching position blocks 570 interact, causing the first position plate 510 to rotate, which in turn drives the limiting plate 540 to rotate until it is aligned with the fitting groove 551; the spring of the support shaft 520 rebounds, pushing the lifting shaft 560 to move up, driving the carrier 210 to rise, the transmission block 220 to disengage from the transmission bar 310, the reset seat 330 drives the transmission bar 310 to move in the opposite direction, the clamping unit 400 retracts to release the workpiece, and the carrier 210 moves upward, so that the transmission block 220 and the transmission bar 310 no longer contact each other, the spring connected to the reset seat 330 retracts, so that the clamping unit 400 moves in the first direction, stops clamping the workpiece, and allows the workpiece to be smoothly removed from the table 100.

[0045] In more specific plans, such as Figure 8As shown, the disassembly unit 500 includes a first displacement plate 510, a support shaft 520, a second displacement plate 530, a limiting plate 540, and a positioning ring 550. The support shaft 520 is provided on the top of the first displacement plate 510, and the second displacement plate 530 is provided on the top of the support shaft 520. When the pressure unit 200 carries the workpiece, the second displacement plate 530 moves towards the first displacement plate 510, compressing the support shaft 520. The corresponding surfaces of the second displacement plate 530 and the first displacement plate 510 are provided with mutually misaligned displacement blocks 570. A lifting shaft 560 is fixedly connected to the top of the second displacement plate 530. When the pressing unit 200 carries the workpiece, that is, when the carrier 210 first presses the disassembly unit 500, the lifting shaft 560 moves downward to press the second displacement plate 530 downward, causing the support shaft 520 to be compressed. A spring is provided on the outer side of the support shaft 520. As the lifting shaft 560 moves downward, its lower surface approaches the upper surface of the first displacement plate 510, and the two sets of displacement blocks 570 press against each other. Due to the misalignment of the two sets of displacement blocks 570 and the provision of matching inclined surfaces, the first displacement plate 510 rotates. Through the cooperation of the second displacement plate 530 with the wedge-shaped block of the first displacement plate 510, the second displacement plate 530 is driven... The second displacement plate 530 rotates, thereby driving the support shaft 520 and the lifting shaft 560 to rotate synchronously. A limit plate 540 is provided on the outer side of the lifting shaft 560. A hole is opened in the bottom wall of the first cavity 120, and a positioning ring 550 is fixedly installed in the hole. The positioning ring 550 has a fitting groove 551. The inner wall of the fitting groove 551 is adapted to the outer edge of the second displacement plate 530. The rotation of the lifting shaft 560 drives the limit plate 540 to rotate, so that the limit plate 540 cannot pass through the fitting groove 551. The overall length of the disassembly unit 500 is shortened. After the workpiece is engraved, the carrier 210 is pressed to make the carrier... 210 drives the lifting shaft 560 to move downward again, and the two sets of displacement blocks 570 squeeze each other again, causing the first displacement plate 510 to rotate. The rotation of the first displacement plate 510 drives the limiting plate 540 to rotate. When the limiting plate 540 rotates again, it can pass through the fitting groove 551. Under the elastic force of the support shaft 520 and the spring, since the limiting plate 540 is not blocked, the lifting shaft 560 pushes the carrier 210 to move upward, causing the transmission block 220 to separate from the end of the transmission bar 310. The clamping unit 400 moves in the second direction, and the workpiece is no longer clamped and can be removed from the top of the platform 100.

[0046] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. The present invention is not limited to the above embodiments; the embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A portable laser engraving machine, characterized in that, include: The platform (100) is installed inside the body of the engraving machine; A pressure-bearing unit (200) is installed on the top of the platform (100). The pressure-bearing unit (200) includes a carrier (210) for bearing the workpiece, and the carrier (210) sinks with the weight of the workpiece when the workpiece is placed. The transmission unit (300) includes a transmission bar (310), which drives the transmission bar (310) to move in a first direction when the carrier (210) sinks, and the transmission bar (310) moves in a second direction when the workpiece is removed from the top of the carrier (210). At least four clamping units (400) have clamping and releasing states. When the transmission bar (310) moves in the first direction, the clamping units (400) move synchronously in the direction of the carrier (210) and fix the workpiece at the center of the platform (100). When the transmission bar (310) moves in the second direction, the clamping units (400) are switched to the releasing state and the workpiece is stopped from being fixed. The clamping unit (400) includes a clamping plate (410). When clamping, the transmission bar (310) is locked in conjunction with the clamping plate (410) to avoid excessive clamping force.

2. The portable laser engraving machine according to claim 1, characterized in that: The top of the platform (100) is provided with a first cavity (120), the pressure-bearing unit (200) is installed in the first cavity (120) and allows the pressure-bearing unit (200) to move up and down along the first cavity (120). The pressure-bearing unit (200) also includes a transmission block (220), the transmission block (220) is disposed at the bottom of the carrier (210), one side of the transmission block (220) and one end of the transmission bar (310) form a mutually compatible inclined surface, the top of the transmission bar (310) is provided with a rack and meshes with a gear (320), the bottom of the clamping unit (400) is provided with a rack and meshes with the gear (320).

3. The portable laser engraving machine according to claim 2, characterized in that: The clamping unit (400) has an internal cavity. The clamping plate (410) is installed at one end of the cavity and connected to the inner wall of the cavity by a spring. A brake strip (411) is fixedly connected to one side of the clamping plate (410). A brake block (412) is connected to the bottom of the brake strip (411) by a spring. The gear (320) also includes a rotating shaft (321). The gear (320) is connected to the inner cavity of the platform (100) through the rotating shaft (321). A brake ring (322) is provided on the outer side of the rotating shaft (321). A groove is provided at the bottom of the clamping unit (400) to allow the brake block (412) to pass through the groove and contact the brake ring (322).

4. The portable laser engraving machine according to claim 2, characterized in that: When the transmission block (220) moves toward the bottom wall of the first cavity (120), the inclined plane causes the transmission bar (310) to move toward the first direction and drives the gear (320) to rotate, so that the clamping unit (400) moves toward the second direction. The direction where the pressure unit (200) is located is set as the second direction, and the opposite direction is set as the first direction.

5. The portable laser engraving machine according to claim 1, characterized in that: The carrier (210) is provided with a disassembly unit (500) at its bottom. The disassembly unit (500) includes a first displacement plate (510), a support shaft (520), a second displacement plate (530), a limiting plate (540), and a positioning ring (550). The support shaft (520) is provided at the top of the first displacement plate (510), and the second displacement plate (530) is provided at the top of the support shaft (520). When the pressure-bearing unit (200) carries the workpiece, the second displacement plate (530) moves toward the first displacement plate (510) and compresses the support shaft (520). The corresponding surfaces of the second displacement plate (530) and the first displacement plate (510) are provided with displacement blocks (570) that are misaligned with each other.

6. The portable laser engraving machine according to claim 5, characterized in that: The top of the second displacement plate (530) is provided with a lifting shaft (560), and a limit plate (540) is provided on the outside of the lifting shaft (560). The bottom wall of the first groove (120) is provided with a hole, and a positioning ring (550) is fixedly installed in the hole. The positioning ring (550) is provided with a fitting groove (551), and the inner wall of the fitting groove (551) is adapted to the outer edge of the second displacement plate (530).

7. The portable laser engraving machine according to claim 3, characterized in that: The brake block (412) has a pawl, and the outer periphery of the brake ring (322) is provided with ratchet teeth that cooperate with the pawl. Both the pawl and the ratchet teeth are structures that combine inclined guide surfaces and stop surfaces. When the brake block (412) and the brake ring (322) are in contact and engaged, the pawl and the ratchet teeth form a unidirectional constraint, allowing the brake ring (322) to rotate in the second direction only, so that the shaft (321) and the gear (320) can only rotate in the second direction.

8. The portable laser engraving machine according to claim 2, characterized in that: The bottom of the transmission bar (310) is provided with a groove, and a reset seat (330) is provided in the groove. The reset seat (330) is connected to the inner wall of the groove by a spring.

9. The portable laser engraving machine according to claim 2, characterized in that: The first slot (120) is also provided with a disc spring (230), the preload of which can be adjusted, a pad (240) is provided at the bottom of the disc spring (230), and a bolt (110) is provided at the bottom of the platform (100).

10. The portable laser engraving machine according to claim 1, characterized in that: The platform (100) has a second cavity (130) on its inner side. The clamping unit (400) is disposed in the second cavity (130). When the four clamping units (400) move synchronously toward the pressure unit (200) and clamp and fix the workpiece placed on the pressure unit (200), the clamping unit (400) is in a clamping state. When the four clamping units (400) move toward the inner cavity of the second cavity (130) and stop clamping the workpiece, the clamping unit (400) is in a released state.

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