WO2016138857A1

WO2016138857A1 - 3d printer

Info

Publication number: WO2016138857A1
Application number: PCT/CN2016/075314
Authority: WO
Inventors: 蔡东濠
Original assignee: 蔡东濠
Priority date: 2015-03-02
Filing date: 2016-03-02
Publication date: 2016-09-09
Also published as: CN204674034U; HK1208121A2

Abstract

A 3D printer, comprising a modeling platform (9) and a resin container (8); and also comprising: a tray (6) fixedly connected to the resin container (8); a lever traction apparatus; and an eccentric structure with one end hinged to a movable end of the lever traction apparatus, wherein the other end of the eccentric structure and one side of the tray (6) form a moving pair. The printer can realize the stable separation of a modeling platform from an adhesive film on the surface of a resin container, thereby avoiding the adhesive film against the damage caused by the tension, and guaranteeing the precision and the quality of a printed product. Even if the 3D printer is used for a long time, the integral structure of the 3D printer cannot be damaged.

Description

a 3D printer

Technical field

The present invention relates to the field of three-dimensional printing technology, and in particular to a 3D printer.

Background technique

Laser stereo printer (Laser 3D Printer), that is, a 3D printer, must use a photosensitive resin as a curing material during operation, and the photosensitive resin used has a relatively high liquid concentration and viscosity. At the time of printing, the resin container containing the photosensitive resin and the modeling platform for modeling the product are in a state of being absolutely balanced and absolutely flat. The surface of the resin container has a film of glue which is irradiated to the photosensitive resin when the film is level with the modeling platform. Since the photosensitive resin needs to be layer-by-layer formed by laser irradiation layer by layer, it is necessary to raise the modeling platform in the Z-axis direction according to the thickness to be formed for each layer, so that the product to be printed has sufficient space to be cured layer by layer. forming. However, it is necessary to pull the surface film and the modeling platform of the resin container which is absolutely flattened up and down vertically, and it requires a lot of force. Since the photosensitive resin is cured, the adhesive force is still quite high, and the photosensitive resin itself has a high concentration. This creates a large tension between the resin container and the modeling platform. Since the products to be printed have hundreds or even thousands of layers, it is possible to resin the resin after repeated repeated vertical upward pulling operations. The film on the surface of the container is forcibly pulled, causing the printing to fail, or causing structural damage to the 3D printer due to excessive long-term hard pulling. In order to solve the above tension problem, it is ensured that the 3D printer can be used for a long time, and the success of the printed product becomes an urgent problem to be solved in the technical field.

At present, the person skilled in the art generally directly uses a stepping motor with a screw rod to directly pull the modeling platform. Although this method can achieve the desired separation effect, the stepping motor is very different in the case of different forces. Prone to "walking" The situation has greatly affected the accuracy of the printed products, and it also needs to be adjusted and maintained frequently, which causes considerable inconvenience to the user. In addition, due to the long-term use of the above structure, the mechanical structure of the 3D printer will also undergo large deformation, which will eventually lead to The chain reaction makes the printed products less than the required precision. In addition, the above structure can only be applied to printing products of a small area, and since it is impossible to adjust the pulling force by itself, only one setting can be made.

For an example of the above direct pull modeling platform, refer to <<CN 104191625 / The table assembly of the DLP light-curing 3D printer>>, the first embodiment and the figure 1 show an example in which the motor-driven cam 11 directly pulls the link 12 to cause separation.

In addition, there are some other technicians in the field who use the left and right push method to break the modeling platform by a momentary action by a large-scale action, and also achieve the desired separation effect, but it is easy to cause 3D due to the large motion range. The deformation of the overall mechanical structure of the printer and the looseness of the connecting member greatly increase the maintenance cost, and the photosensitive resin contained in the resin container is also likely to overflow, increasing the probability of damage of the resin container and wasting the photosensitive resin raw material.

As described above, although the skilled person has tried various ways to solve the aforementioned problems, it has not been able to achieve the desired effect.

Summary of the invention

In view of the above technical problems, and the deficiencies of the technical means adopted by those skilled in the art at this stage, the object of the present invention is to provide a 3D printer capable of achieving smooth separation of the film on the surface of the modeling platform and the resin container, and avoiding the film. It is easily damaged due to pulling, ensuring the accuracy and quality of printed products. And long-term use will not damage the overall structure of the 3D printer.

In order to achieve the above object, the technical solution adopted by the present invention is:

A 3D printer comprising a modeling platform and a resin container;

The utility model further comprises: a tray fixedly connected to the resin container; a lever pulling device; an eccentric structure whose one end is hinged with a movable end of the lever pulling device; and the other end of the eccentric structure forms a moving pair with one side of the tray.

Further, the lever traction structure includes a power unit, a transmission structure, and an execution structure.

Further, the power device is one of a stepping motor, a servo motor, a DC motor, an AC motor, and a pneumatic motor.

Further, the transmission structure is a gear transmission structure, and the gear transmission structure includes a driving gear coupled to the output end of the power unit and a driven gear engaged with the driving gear.

Further, the execution structure includes a connecting rod, a fixing frame and a lever; a center of the driven gear is hinged to the fixing frame; one end of the connecting rod is hinged at a center of the proximal driven gear to obtain a larger Torque; one end of the lever is hinged to the other end of the connecting rod, the fulcrum of the lever is hinged to the fixed frame, and the other end of the lever serves as the movable end of the lever pulling device.

Further, the eccentric structure is an unequal triangle, and one end of the unequal triangle has a hinge point hinged to the movable end of the lever pulling device, and the other end has at least two guide rods or sliders, and is movable The ground is mounted in a chute or rail on one side of the fixed rack.

Further, the positional relationship of the three corners of the unequal square is determined according to the length of the tray, the liquid concentration of the resin, the viscosity, and the positional relationship of the gear transmission structure.

Further, a plurality of fixed shafts for supporting the tray are further included.

Further, the moving pair is composed of one or more holes on one side of the tray hinged with the eccentric structure.

By adopting the above configuration, the lever pulling device of the 3D printer of the present invention can pull down the tray by the principle of the lever, thereby lowering the resin container, and then causing the left and right swings between the lowered resin container and the modeling platform by the eccentric structure, thereby The separation between the modeling platform and the surface of the resin container is further increased. The driven gear, the connecting rod, the fulcrum of the fixing frame and the end of the lever actually constitute a link mechanism, and the stepping motor drives the driving gear to drive the driven gear to rotate one week. For a complete stroke, in the stroke, the lever pulls the unequal triangle with the driven gear, first pulls down the tray and then drives the tray to shake left and right under the action of the surface tension and adhesion of the film and the modeling platform, the modeling platform and After the film separation rises, the whole stroke is completed, the lever returns to the initial position, and the unequal triangle is driven, and then the tray is dragged to return to the horizontal state. With a simple mechanical structure, the smooth separation of the modeling platform and the film can be achieved, the precision of the printed product can be ensured, and no large impact is generated. In the separation process, the lever pulling device and the eccentric structure can play together. The "unloading force" buffer acts to avoid damage to the overall structure of the 3D printer due to repeated heavy traction.

The principles and advantages are summarized as follows:

1. Using the gear, lever traction device and eccentric structure principle to pull the moving pair can drive a larger pulling force, enough to generate torque and easily twist the tray.

2. When the small workpiece is printed, the force obtained by the gear, the lever pulling device and the eccentric structure principle is enough to make the modeling platform and the resin container angled and separated from the film on the resin container. But when printing a large area, There is a great tension between the modeling platform and the resin container. The strength of the gear, lever traction device and eccentric structure principle is enough to break the film to separate. In order to avoid this situation, Deliberately conceived the mobile pair (one end of the eccentric structure is hinged to the lever pulling device and the other end forms a moving pair with one side of the tray), thereby moving the pull-up force to the side, causing the tray to be bent at a corner, and a certain resilience, The tray will be pulled back to the original straight state, the whole process is to bring out the flexibility of the twisting, so that when printing a large flat product, the modeling platform can be angled with the resin container and the film on the resin container. Successful separation. The motor and the entire structure achieve the finest strain and long machine life.

3. With the aid of lever tension, the motor can generate more tension with only a small gear. The body size can be small but it can print larger workpieces than other brands.

DRAWINGS

1 is a schematic view showing the composition of a direction of a 3D printer of the present invention, in which a Z-axis with a lead screw for adjusting the modeling platform 9 to slide up and down in a fixed plane is omitted.

2 is a schematic view showing the composition of a partial perspective process in another direction of the 3D printer of the present invention.

3 is a schematic view showing the composition of the partial perspective processing in the other direction of the 3D printer of the present invention, and the position of the stepping motor 18 can be seen.

4(a) is a cross-sectional view showing still another direction of the 3D printer of the present invention, in which the modeling platform and the resin container are in a parallel state.

Figure 4(b) A cross-sectional view of still another direction of the 3D printer of the present invention, wherein the modeling platform and the resin container have an angled inclination.

DESCRIPTION OF REFERENCE NUMERALS: 6-tray; 7-platen; 8-resin container; 9-modeling platform; 11-unequal triangle; 12-lever; 13-surface film; 14-linker; ; 16-driven gear; 17-fixing frame; 18-stepping motor; 19-fixed shaft; 20A, 20B - elliptical hole position.

detailed description

The above described features and advantages of the invention will be apparent from the following description.

The 3D printer of the invention adopts a technology combining the central axis deviation and the lever swing unloading separation, and the specific working principle and structure thereof are as follows:

SLA (Stereo lithography) as shown in Figures 1 to 3 and 4(a) and 4(b) Appearance) Stereolithography and DLP (Digital Light Processing) The working principle of the digital light processor 3D printer is to use a laser to layer the liquid photosensitive resin, so that the photosensitive resin in the resin container 8 is layer-by-layer cured on the surface of the modeling platform 9 on the vertical Z-axis. Each time the next layer of printing is to be performed, the modeling platform 9 needs to drive the photosensitive resin which has just been cured in the previous layer to be separated from the surface film 13 of the resin container 8, and then rise to the level of the next layer that has been set. The laser is then irradiated to the modeling substrate 9 to illuminate the liquid photosensitive resin to cure another layer, and so on. After multiple layers of curing, the product can be molded, and some products may be cured by up to 10,000 layers.

When the molding platform 9 is vertically separated from the surface film 13 of the resin container 8 at the time of printing, the tensile force of the photosensitive resin and the flatness of the two planes generate a large tension.

However, as mentioned above, both the modeling platform 9 and the resin container 8 are capable of accurately printing in an absolute horizontal fit, but must be subjected to multiple steps of layer-by-layer separation and printing, to be successfully clutched without Breaking the surface film 13 of the resin container 8, Printing can be completed and is the core purpose of the present invention.

The structure and working process of the 3D printer of the present invention will be described in detail below with reference to the accompanying drawings:

The structure of the 3D printer of the present invention comprises: a modeling platform 9 and a resin container 8; further comprising: a tray 6 fixedly connected to the resin container 8; a lever pulling device; and an eccentric structure hinged at one end to a movable end of the lever pulling device; The other end of the eccentric structure forms a moving pair with one side of the tray 6 (indicating that any two members remain in contact with each other and can move relative to each other in one direction). The lever traction structure includes a stepping motor 18 as a power unit, a transmission structure, and an execution structure. The transmission structure is a gear transmission structure including a driving gear 15 and a driven gear 16 connected to an output end of the stepping motor 18. The execution structure includes a connecting rod 14, a fixing frame 17, and a lever 12; the center of the driven gear 16 is hinged to the fixing frame 17; one end of the connecting rod 14 is hingedly fixed to the center of the driven gear 16, and is specifically designed to ensure Under the premise that the moving gear 16 and the associated gear shaft do not suffer from breakage damage, the aforementioned hinge point is as close as possible to the axial center position of the driven gear 16. One end of the lever 12 is hinged to the other end of the connecting rod 14, the fulcrum of the lever 12 is hinged to the fixed frame 17, and the other end of the lever 12 serves as the movable end of the lever pulling device.

The eccentric structure is an equilateral triangular plate 11 having a hinge point at one end and hinged with the movable end of the lever pulling device, and the other end has at least two guiding rods, and is movably mounted on the sliding groove on one side of the fixed frame. Inside. The unequal triangle plate 11 is for twisting the bottom plate of the tray 6, so the length of the upper side of the unequal triangle plate 11 is not too short, and the tray is made of 2 mm thick stainless steel, which is about 6:1, that is, the unequal triangle plate 11 The length of the upper side is about 1/6 of the bottom plate of the tray 6. The positional relationship of the three corners of the an equilateral triangular plate 11 depends on the length of the tray 6 to be pulled down and the required pulling force (this pulling force depends on the liquid concentration of the photosensitive resin, the viscosity, and the positional relationship of the gear transmission structure). For example, in one design, assuming that the 3D printer can be applied to a commonly used photosensitive resin, the left side angle is about 45°, the right side angle is about 32°, and the lower angle is about 103°. But it should be noted that the above design is just one of the designs.

The design of the unequal triangular plate 11 for pulling the bottom plate of the tray 6 is within the scope of the present invention.

The working process of the 3D printer of the present invention:

1. The resin container 8 must be separated from each other by the modeling platform 9 on the vertical Z-axis, raised, and then attached to print the next layer.

2. If each layer is raised, it must be pushed by the stepping motor 13 by the Z axis with the lead screw. Let the modeling platform 9 rise up step by step.

3. To remove the huge tension generated when the modeling platform 9 is separated from the resin container 8, it is necessary to rely on a set of part pressing plates 7 below the resin container 8, the tray 6, The unequal square plate 11, the lever 12, the fixed frame 17, the connecting rod 14, the driven gear 16, the driving gear 15, the stepping motor 18 and the fixed shaft 19 work together.

4. The resin container 8 is pressed against the tray 6 of the resin container 8 by a plurality of press plates 7.

5. The resin container 8 can be easily pulled down to drive the driving gear 15 through the stepping motor 18, and then drive the assembly between the driven gear 16 and the tray 6 without the equilateral triangle 11, the lever 12, The connecting rod 14 and the fixing frame 17 constitute a link mechanism, so that the link mechanism can be pulled down by the lever principle, and the resin container 8 can be angularly separated from the modeling platform 9.

6. Since each product has a different profile, the tension and adhesion generated during each layer will be different. To allow the resin container 8 to be completely separated from the modeling platform 9, Then, the entire tray 6 is pulled down by the unequal triangles 11 and then pulled up and down, so that the product which has been solidified on the modeling platform 9 is gently separated from the surface film 13 of the resin container 8.

7. The equilateral square plate 11 can pull the entire tray 6 downward and then pull it left and right to generate a swing because it is mounted at the center point of one side of the tray 6, and the equilateral triangle plate 11 is located in the chute of the tray 6 because it is located. The two sides of the triangle formed by the two pin shafts and the hinge points of the unequal triangle plate 11 and the lever 12 are of an unequal ratio structure, so that when the tray 6 is pulled to a certain strength, the triangular unequal proportion structure exerts a left and right unloading force reaction. Therefore, the tray 6 is swung up and down together, and after the separation operation is completed, the tray 6 and the resin container 8 are automatically returned to the original position by the action of the lever 12, so that the cured layer can be accurately re-printed each time. The surface film 13 of the resin container 8 is absolutely horizontally bonded and printing is continued until completion.

8. In another embodiment, the moving pair is provided by one or more holes on one side of the tray, such as elliptical holes 20A, 20B, It is composed of an articulated structure. When the non-equal triangle plate 11 pulls down the entire tray 6, the above-mentioned triangular unequal proportion structure moves along the gap left by the elliptical hole positions 20A, 20B. Therefore, the tray 6 is swayed and pulled down from left to right. Since the tray 6 has a certain flexibility, the pull-down width can be automatically adjusted according to the adhesive force of the resin to prevent the pulling force from being excessively pulled and the surface adhesive film 13 from being pulled.

During the above work, the function of the positioning shaft 19 is to strengthen the protection. If the connection between the equilateral triangle plate 11 and the lever 12 is broken, the positioning shaft 19 can be used to support the tray 6 and the resin container 8. To prevent the two from falling. In addition, the connection position of the positioning shaft 19 and the tray 6 has a certain gap, and the tray 6 can be appropriately swayed from side to side.

The invention produces a stepping motor 18, a driving gear 15, a driven gear 16, a connecting rod 14, and a fixing frame 17, The lever 12, the unequal triangle plate 11, the pressure plate 7, the fixed shaft 19, the elliptical hole positions 20A, 20B and the tray 6 are assembled, and are mainly driven by a stepping motor to generate a lever pulling force to cause the modeling platform 9 to be pulled. under, The equilateral triangular plate 11 can swing left and right. The modeling platform 9 is oscillated to be separated from the resin container 8. The invention has completed a number of practical tests and applications, and the printing and separation effects are good, and the printing accuracy can be made up to 0.01 mm per layer. From experience, The opportunity of error is obviously improved by the prior art. Of course, the present invention discloses the above structure, and the specific testing process should be well known to those skilled in the art, and according to the specific working principle described above, those skilled in the art should be able to easily It is understood that the above-described printing accuracy and the chance of error are inevitably achieved by the above structure. Therefore, the specific products for the actual test and application process and printing are not described again.

The present invention mainly utilizes the principle of lever to pull out the pulling force to cause a natural physical reaction phenomenon, and effectively resolves the tension and the adhesive force generated between the surface adhesive film 13 of the resin container 8 and the modeling platform 9. The invention is based on the use of a motor (such as a stepping motor) to drive the lever 12 through the transmission device, and generates a pulling force to pull the unequal triangle plate 11, which causes the unequal edge triangular plate 11 to naturally swing, when the pulling force is sufficient for the modeling platform 9 and just The cured photosensitive resin is separated from the surface adhesive film 13, and only an appropriate pulling force is generated, but when the pull-up force is insufficient to separate the modeling platform 9 and the newly cured photosensitive resin from the adhesive film 13, the equilateral triangular plates 11 naturally interact with each other. Pulling down the pulling force and continuing to pull down, while running, because it is not equal to the triangular structure, under the downward pulling force, it will naturally pull

Pulling the tray 6 to the side with less proportion, and then generating corresponding internal stress, and causing the tray 6 to produce non-average bending, according to the tension and adhesion force generated between the surface film of the resin container 8 and the modeling platform 9. Different degrees, different degrees of bending will occur, and finally the offset and adhesion force will be offset to make the film on the surface of the resin container 8 and the modeling platform 9 completely unbroken and effectively separated. At the same time, it does not constitute mechanical deformation and damage, and the processed products can achieve the best precision and complete printing.

In summary, the present invention utilizes physical natural phenomena, and the principle of leverage achieves different tension and adhesion conditions. Automatically generate physical stress changes according to different tension and bonding strength, thereby relieving high tension and adhesion to achieve the desired effect.

Since the structure of the present invention is mainly designed by using natural physical phenomena, the fabrication and installation are simple, the durability is extremely low, the cost is low, the effect is large, the tension and the tension can be dealt with, the maintenance is extremely easy, and the market acceptance is extremely high. For users in various industries, this technology can greatly improve the printing production speed, reduce the user's often caused by the film being broken and cause printing failure, greatly reducing the loss of time and money. Absolutely help the future of the huge 3D printing market. Moreover, the separation structure of the 3D printer of the present invention requires almost no maintenance, can be used for a long time, and has low production cost, and is technically integrated with various advantages.

It should be noted that the tray 6 may be made of a metal material or other suitable hard materials, which is not limited by the present invention.

The unequal triangular plate 11 is only used to illustrate the eccentric structure. The present invention is not limited to the eccentric structure adopting the structure. According to actual working conditions, the eccentric structure can also be designed by other methods. For example, the triangular plate structure can be used without using the triangular structure. The rigid rods of unequal length are connected end to end to make an eccentric structure. In short, the eccentric structure is not limited to a specific geometric member, and the eccentric structure and the moving pair of the tray are not limited to being realized by the guide rod and the chute, but also by providing the slider and the guide rail. In short, as long as the eccentric structure is used, one end is hinged to the movable end of the lever pulling device, and the other end forms a moving pair with the center of one side of the tray, and one side in the moving direction of the moving pair forms an unequal with the hinge point. Triangles are all within the scope of the present invention.

The above components: stepper motor 18, drive gear 15, driven gear 16, lever 12, The connecting rod 14 and the fixing frame 17 are only used to illustrate the lever pulling device. The invention is not limited to the lever pulling device adopting the structure. According to the actual working condition, in addition to the stepping motor, for example, a servo motor, a DC motor, and an alternating current can be used. The motor, the air motor, and the like provide power, which is not limited by the present invention. The transmission form is also not limited to gear transmission, and transmission modes such as belt drive, chain drive or worm gear can also be used. The driven gear corresponding to the rocker in the connecting rod structure can also be realized by other means, such as changing to a rigid rod or a cam structure, as long as the connecting structure can be driven to complete a complete stroke, the invention is not limited thereto. The structure of the lever, including the length, the ratio of the force arms, and the angle between them, are determined according to the mechanism of the actual 3D printer. Since the knowledge involved is common knowledge in the mechanical field, it will not be described again.

In conclusion, the above structures and principles are only used to illustrate the technical solutions of the present invention and are not intended to be limiting, and the present invention will be described in detail with reference to the above-described structures and principles, and those of ordinary skill in the art should understand that The technical solutions of the present invention may be modified or equivalently substituted without departing from the spirit and scope of the present invention and the claims. Such modifications or equivalent substitutions are within the scope of the invention.

Claims

A 3D printer includes a modeling platform and a resin container; and the method further includes:

a tray fixedly connected to the resin container; a lever pulling device; an eccentric structure hinged at one end to a movable end of the lever pulling device; and the other end of the eccentric structure forming a moving pair with one side of the tray.
The 3D printer of claim 1 wherein said lever traction structure comprises a power unit, a transmission structure and an actuator structure.
The 3D printer according to claim 2, wherein the power unit is one of a stepping motor, a servo motor, a DC motor, an AC motor, and a pneumatic motor.
A 3D printer as claimed in claim 2, wherein said transmission structure is a gear transmission structure, said gear transmission structure comprising a drive gear coupled to the output end of the power unit and a meshing engagement with said drive gear Driven gear.
The 3D printer according to claim 2, wherein the execution structure comprises a connecting rod, a fixing frame and a lever; a center of the driven gear is hinged to the fixing frame; and one end of the connecting rod is hinged to Near the center of the driven gear; one end of the lever is hinged to the other end of the connecting rod, the fulcrum of the lever is hinged to the fixed frame, and the other end of the lever acts as the movable end of the lever pulling device.
A 3D printer according to claim 5, wherein said eccentric structure is an equilateral triangular plate, and one end of said equilateral triangular plate has a hinge point hinged to the movable end of the lever pulling device, and the other end has At least two guides or sliders are movably mounted in the chute or rail on one side of the fixed frame.
The 3D printer according to claim 6, wherein the positional relationship of the three corners of the unequal square is determined according to the length of the tray, the liquid concentration of the resin, the viscosity, and the positional relationship of the gear transmission structure. .
A 3D printer according to claim 1, wherein said resin container is fixed to said tray by a plurality of press plates.
A 3D printer according to claim 1, further comprising a plurality of fixed shafts coupled to said tray for supporting the tray.
The 3D printer of claim 8 wherein said fixed shaft has a gap at the junction with the tray.
The 3D printer of claim 1 wherein said moving pair is formed by articulating one or more apertures on one side of the tray with the eccentric structure.