阅读说明：本技术 刮刀稳定系统 (Doctor blade stabilizing system ) 是由 于清晓 杜迪坤 于 2015-09-08 设计创作，主要内容包括：本申请提供一种刮刀稳定系统,包括：真空泵；刮刀,具有气路连通所述真空泵的刮刀真空内腔；传感器,与所述刮刀真空内腔相连通以实时检测的所述刮刀真空腔内的真空度信息；主控制器,电性连接所述传感器以及真空泵,用于实时接收由所述传感器实时反馈的刮刀真空腔内的真空度信息,并依据所述真空度信息控制所述真空泵转速以连续性调整所述刮刀真空腔内的真空度；进而解决现有技术中利用调节阀对刮刀真空腔负压调节时容易导致腔内液面不稳、树脂过吸及控制稳定性低的缺陷导致的刮刀真空度难以精确控制的问题。(The present application provides a doctor blade stabilization system comprising: a vacuum pump; the scraper is provided with a scraper vacuum inner cavity communicated with the vacuum pump through a gas path; the sensor is communicated with the scraper vacuum cavity to detect the vacuum degree information in the scraper vacuum cavity in real time; the main controller is electrically connected with the sensor and the vacuum pump and is used for receiving the vacuum degree information in the scraper vacuum cavity fed back by the sensor in real time and controlling the rotating speed of the vacuum pump according to the vacuum degree information so as to continuously adjust the vacuum degree in the scraper vacuum cavity; and then solve among the prior art and utilize the governing valve to lead to the problem that the scraper vacuum degree that the defect that the intracavity liquid level is unstable, resin cross-absorption and control stability are low leads to easily when adjusting scraper vacuum cavity negative pressure is difficult to accurate control.)

1. A doctor blade stabilization system, comprising:

A vacuum pump;

The scraper is provided with a scraper vacuum inner cavity communicated with the vacuum pump through a gas path;

The sensor is communicated with the scraper vacuum cavity to detect the vacuum degree information in the scraper vacuum cavity in real time;

And the main controller is electrically connected with the sensor and the vacuum pump and is used for receiving the vacuum degree information in the scraper vacuum cavity fed back by the sensor in real time and controlling the rotating speed of the vacuum pump to continuously adjust the vacuum degree in the scraper vacuum cavity according to the vacuum degree information.

2. the doctor blade stabilization system of claim 1, wherein the main controller has a threshold range pre-stored therein, the threshold range being determined by a target threshold value, the target threshold value being a pressure value within the doctor blade vacuum chamber or a liquid level height value within the doctor blade vacuum chamber; and the vacuum degree information in the scraper vacuum cavity is a pressure value in the scraper vacuum cavity or a liquid level height value in the scraper vacuum cavity.

3. The doctor blade stabilizing system according to claim 1, wherein the main controller is configured to receive vacuum degree information in the doctor blade vacuum chamber fed back by the sensor in real time, and control the rotation speed of the vacuum pump according to the vacuum degree information to continuously adjust the vacuum degree in the doctor blade vacuum chamber, including matching the obtained vacuum degree information with a preset threshold range, and controlling the rotation speed of the vacuum pump according to the matching result to continuously adjust the vacuum degree in the doctor blade vacuum chamber, so that the vacuum degree is maintained within the threshold range.

4. the doctor blade stabilization system according to claim 2, wherein the step of controlling the rotational speed of the vacuum pump to continuously adjust the vacuum level within the doctor blade vacuum chamber according to the matching results comprises: if the vacuum degree information in the scraper vacuum cavity acquired by the main controller is smaller than the lower threshold limit in the threshold range, the main controller controls the vacuum pump to increase the rotating speed; if the vacuum degree information in the scraper vacuum cavity acquired by the main controller is larger than the upper threshold limit in the threshold range, the main controller controls the vacuum pump to stop working; and if the vacuum degree information in the scraper vacuum cavity acquired by the main controller is within a threshold range, the main controller controls the vacuum pump to keep the current rotating speed.

5. The doctor blade stabilization system of claim 2, further comprising a throttle device disposed on the evacuation line between the vacuum pump and the doctor blade vacuum chamber, the throttle device being electrically connected to the main controller and adjusting the air intake rate in accordance with instructions from the main controller.

6. The doctor blade stabilization system according to claim 5, wherein the throttling device is a gas solenoid valve or a gas throttle valve.

7. The doctor blade stabilization system of claim 5, further comprising a control box communicatively disposed between the vacuum pump and the throttling device for buffering sudden changes in air pressure within the doctor blade vacuum chamber to prevent resin over-suction.

8. The doctor blade stabilization system of claim 7, wherein the step of controlling the rotational speed of the vacuum pump to continuously adjust the vacuum level within the doctor blade vacuum chamber based on the matching results comprises: if the vacuum degree information in the scraper vacuum cavity acquired by the main controller is smaller than the lower threshold limit in the threshold range, the main controller controls the vacuum pump to increase the rotating speed; if the vacuum degree information in the scraper vacuum cavity acquired by the main controller is larger than the upper threshold limit in the threshold range, the main controller controls the throttling device to increase the air inlet speed and reduce the rotating speed of the vacuum pump; and if the vacuum degree information in the scraper vacuum cavity acquired by the main controller is within the threshold range, the main controller controls the vacuum pump to keep the current rotating speed.

9. the doctor blade stabilization system of claim 1, wherein the vacuum pump is a suction-type vacuum pump or a blow-type vacuum pump.

10. The doctor blade stabilization system of claim 1, wherein the sensor is a pressure sensor, a differential pressure sensor, a displacement sensor, or a position sensor.

11. The doctor blade stabilization system of claim 1, wherein the master controller comprises an industrial personal computer, a PLC, a MCU, a microprocessor, a FPGA, an ARM, a DSP, or a single chip microcomputer.

Technical Field

The application relates to the technical field of photocuring molding, in particular to a scraper stabilizing system.

Background

The laser light curing forming printer is called SLA for short, is a printing device which adopts the three-dimensional carving principle and is quickly formed, is suitable for manufacturing small and medium-sized workpieces and can directly obtain resin or similar engineering plastic products.

The SLA process is a molding technology for manufacturing a 3D model by irradiating photosensitive resin with laser and performing layered curing. In the curing process, the lifting platform descends by one layer of distance, the scraper coating system covers another layer of liquid resin on the curing layer, then the second layer of scanning is carried out, the second curing layer is firmly bonded on the previous curing layer, and the second curing layer is accumulated for multiple times and is stacked layer by layer until the whole solid modeling is manufactured. Coating technology is one of the key technologies for photocuring rapid prototyping, and aims to obtain a precise and uniform thin resin layer on the upper surface of a cured resin in as short a time as possible. After the scraper is adopted for scraping and cutting, the required amount of resin can be coated on the upper lamination layer very uniformly, so that better precision can be obtained after laser curing, and the surface of the product is smoother and smoother. Thus, the doctor blade has a significant impact on the SLA printing quality and even determines whether the printing process can be completed.

At present, the scraper among the prior art adopts the vacuum adsorption scraper more, and the scraper blade adsorbs the scraper inner chamber with liquid resin when printing the liquid level upward movement, but the ubiquitous inner chamber pressure of current vacuum adsorption scraper is unstable, and the intracavity liquid level is unstable promptly, leads to easily printing the working face liquid level unstability, prints the liquid level bubble and can't clear away, causes to print work piece size unstability, prints the failure even.

The existing light curing forming equipment adopts a vacuum pump and an adjusting valve to control the vacuum degree of a scraper vacuum cavity, and the adjustment of negative pressure in the scraper vacuum cavity is mainly realized by adjusting the adjusting valve, but the defects that the liquid level in the scraper vacuum cavity is unstable, resin is easy to over-absorb, the vacuum adjustment is inconvenient, the pressure control is inaccurate and the like exist. Therefore, a stable and reliable doctor vacuum control scheme is needed.

Disclosure of Invention

In view of the above drawbacks of the prior art, an object of the present application is to provide a doctor blade stabilizing system, which is used to solve the problem in the prior art that the vacuum degree of a doctor blade is difficult to be accurately controlled due to the defects that the liquid level in a cavity is unstable, resin is excessively absorbed, and the control stability is low when a regulating valve is used for regulating the vacuum pressure of a vacuum cavity of the doctor blade.

To achieve the above and other related objects, a first aspect of the present application provides a doctor blade stabilizing system comprising: a vacuum pump; the scraper is provided with a scraper vacuum inner cavity communicated with the vacuum pump through a gas path; the sensor is communicated with the scraper vacuum cavity to detect the vacuum degree information in the scraper vacuum cavity in real time; and the main controller is electrically connected with the sensor and the vacuum pump and is used for receiving the vacuum degree information in the scraper vacuum cavity fed back by the sensor in real time and controlling the rotating speed of the vacuum pump to continuously adjust the vacuum degree in the scraper vacuum cavity according to the vacuum degree information.

In certain embodiments of the first aspect of the present application, the main controller pre-stores a threshold range, the threshold range being determined by a target threshold value, the target threshold value being a pressure value in the scraper vacuum chamber or a height value of a liquid level in the scraper vacuum chamber; and the vacuum degree information in the scraper vacuum cavity is a pressure value in the scraper vacuum cavity or a liquid level height value in the scraper vacuum cavity.

In certain embodiments of the first aspect of the present application, the step of the main controller receiving vacuum degree information in the scraper vacuum chamber fed back by the sensor in real time, and controlling the vacuum pump rotation speed to adjust the vacuum degree in the scraper vacuum chamber continuously according to the vacuum degree information includes matching the obtained vacuum degree information with a preset threshold range, and controlling the rotation speed of the vacuum pump to adjust the vacuum degree in the scraper vacuum chamber continuously according to a matching result, so that the vacuum degree is maintained in the threshold range.

In certain embodiments of the first aspect of the present application, the step of controlling the rotation speed of the vacuum pump according to the matching result to continuously adjust the degree of vacuum in the scraper vacuum chamber comprises: if the vacuum degree information in the scraper vacuum cavity acquired by the main controller is smaller than the lower threshold limit in the threshold range, the main controller controls the vacuum pump to increase the rotating speed; if the vacuum degree information in the scraper vacuum cavity acquired by the main controller is larger than the upper threshold limit in the threshold range, the main controller controls the vacuum pump to stop working; and if the vacuum degree information in the scraper vacuum cavity acquired by the main controller is within a threshold range, the main controller controls the vacuum pump to keep the current rotating speed.

In certain embodiments of the first aspect of the present application, the doctor blade stabilizing system further includes a throttling device disposed on the vacuum line between the vacuum pump and the doctor blade vacuum chamber, the throttling device is electrically connected to the main controller and adjusts the air intake speed according to the instruction of the main controller.

In certain embodiments of the first aspect of the present application, the throttling device is a gas solenoid valve or a gas throttle valve.

in certain embodiments of the first aspect of the present application, the doctor blade stabilizing system further comprises a control box, communicatively disposed between the vacuum pump and the throttling device, for buffering sudden changes in air pressure in the doctor blade vacuum chamber to prevent resin over-suction.

In certain embodiments of the first aspect of the present application, the step of controlling the rotation speed of the vacuum pump according to the matching result to continuously adjust the degree of vacuum in the scraper vacuum chamber comprises: if the vacuum degree information in the scraper vacuum cavity acquired by the main controller is smaller than the lower threshold limit in the threshold range, the main controller controls the vacuum pump to increase the rotating speed; if the vacuum degree information in the scraper vacuum cavity acquired by the main controller is larger than the upper threshold limit in the threshold range, the main controller controls the throttling device to increase the air inlet speed and reduce the rotating speed of the vacuum pump; and if the vacuum degree information in the scraper vacuum cavity acquired by the main controller is within the threshold range, the main controller controls the vacuum pump to keep the current rotating speed.

in certain embodiments of the first aspect of the present application, the vacuum pump is a suction-type vacuum pump or a blow-type vacuum pump.

In certain embodiments of the first aspect of the present application, the sensor is a pressure sensor, a differential pressure sensor, a displacement sensor, or a position sensor.

In certain embodiments of the first aspect of the present application, the master controller comprises an industrial personal computer, a PLC, a MCU, a microprocessor, an FPGA, an ARM, a DSP, or a single chip microcomputer.

The second aspect of the application provides a scraper vacuum degree control method, which comprises the following steps: starting a throttling device; setting a threshold range, wherein the threshold range comprises a target threshold; controlling a vacuum pump to pump air into the scraper vacuum cavity by a main controller, and simultaneously enabling the main controller to acquire the fed back pressure difference inside the scraper vacuum cavity in real time and compare the pressure difference with the target threshold value so as to execute the following steps: when the pressure difference in the scraper vacuum cavity is within the threshold range, enabling the main controller to keep the rotating speed of the vacuum pump, and simultaneously acquiring the feedback pressure difference in the scraper vacuum cavity in real time; when the pressure difference level inside the scraper vacuum cavity is smaller than the lower threshold of the threshold range, the main controller is made to control the vacuum pump to increase the rotating speed, and meanwhile, the feedback pressure difference inside the scraper vacuum cavity is obtained in real time; and when the internal pressure difference level of the scraper vacuum cavity is greater than the upper threshold limit of the threshold range, the main controller controls the throttling device to increase the air inlet speed and reduce the rotating speed of the vacuum pump, and meanwhile, the feedback internal pressure difference of the scraper vacuum cavity is obtained in real time.

as mentioned above, the blade stabilizing system of the present application has the following beneficial effects: by introducing feedback information of the sensor and comparing the feedback information with a preset threshold range, the main controller can adjust the rotating speed of the vacuum pump in real time to ensure that the set vacuum degree in the scraper vacuum cavity is quickly and accurately reached; the method can more quickly and stably reach the set threshold range, ensures the stability of the resin liquid level in the scraper vacuum cavity, and improves the precision of the planar light curing rapid molding solid modeling.

Drawings

Fig. 1 is a schematic diagram of a blade stabilizing system according to an embodiment of the present disclosure.

Figure 2 is a flow chart illustrating operation of the blade stabilization system of the present application in one embodiment.

Detailed Description

The following description of the embodiments of the present application is provided for illustrative purposes, and other advantages and capabilities of the present application will become apparent to those skilled in the art from the present disclosure.

In the following description, reference is made to the accompanying drawings that describe several embodiments of the application. It is to be understood that other embodiments may be utilized and that mechanical, structural, electrical, and operational changes may be made without departing from the spirit and scope of the present disclosure. The following detailed description is not to be taken in a limiting sense, and the scope of embodiments of the present application is defined only by the claims of the issued patent. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. Spatially relative terms, such as "upper," "lower," "left," "right," "lower," "below," "lower," "above," "upper," and the like, may be used herein to facilitate describing one element or feature's relationship to another element or feature as illustrated in the figures.

Also, as used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context indicates otherwise. It will be further understood that the terms "comprises," "comprising," "includes" and/or "including," when used in this specification, specify the presence of stated features, steps, operations, elements, components, items, species, and/or groups, but do not preclude the presence, or addition of one or more other features, steps, operations, elements, components, species, and/or groups thereof. The terms "or" and/or "as used herein are to be construed as inclusive or meaning any one or any combination. Thus, "A, B or C" or "A, B and/or C" means "any of the following: a; b; c; a and B; a and C; b and C; A. b and C ". An exception to this definition will occur only when a combination of elements, functions, steps or operations are inherently mutually exclusive in some way.

as can be seen from the above description of the background art, in the photo-curing 3D printing apparatus, the liquid level control of the resin in the resin tank (including the liquid level stability and the bubbles generated during the movement of the scraper) is an important link regarding the printing quality, so that it is only necessary to provide a vacuum chamber in the scraper to control the stability of the liquid level below the scraper by adjusting the air pressure in the vacuum chamber. The vacuum degree of a scraper vacuum cavity is controlled by a vacuum pump and an adjusting valve in the existing light curing forming equipment, the adjustment of negative pressure in the scraper vacuum cavity is mainly realized by adjusting the adjusting valve, namely, when the vacuum degree information in the scraper vacuum cavity is higher than the upper threshold limit or lower than the lower threshold limit, the vacuum degree is adjusted through an electromagnetic valve, and the defects that the liquid level in the scraper vacuum cavity is unstable, resin is easy to over-absorb, the vacuum adjustment is inconvenient, the pressure control is inaccurate and the like are easily caused by the stage adjustment through practical use discovery.

The application provides a scraper stable system aims at adjusting through the continuity vacuum in the scraper vacuum chamber avoids making promptly atmospheric pressure in the scraper vacuum chamber jumps to make the pressure of scraper vacuum chamber more stable, in order to solve and have the problem among the prior art, scraper stable system include vacuum pump, scraper, sensor to and main control unit.

The rotational speed change of vacuum pump can produce different air currents, in this application, comes real-time adjustment scraper vacuum degree through the regulation of vacuum pump rotational speed, and in some embodiments, the vacuum pump is the type vacuum pump of bleeding or the type vacuum pump of blowing. In an exemplary embodiment, the vacuum pump is described as an evacuation type vacuum pump.

The scraper is provided with a scraper vacuum inner cavity communicated with the vacuum pump through a gas path; in an embodiment, the scraper vacuum chamber is in communication with the vacuum pump via a vacuum line.

The sensor is communicated with the scraper vacuum cavity and is used for detecting vacuum degree information in the scraper vacuum cavity in real time; in an embodiment, in order to obtain the vacuum degree in the scraper vacuum chamber, the sensor may be a pressure sensor, a differential pressure sensor, a displacement sensor, or a position sensor, that is, the vacuum degree information may be a pressure value in the scraper vacuum chamber, or may also be a liquid level height value in the scraper vacuum chamber. The selection of the sensor is consistent with the parameters corresponding to the threshold range, and if the sensor is a pressure sensor, the threshold range is a pressure range value. In an embodiment, the vacuum degree information in the scraper vacuum cavity is a pressure value in the scraper vacuum cavity or a liquid level height value in the scraper vacuum cavity.

The main controller is electrically connected with the sensor and the vacuum pump and used for receiving the vacuum degree information in the scraper vacuum cavity fed back by the sensor in real time and controlling the rotating speed of the vacuum pump according to the vacuum degree information to continuously adjust the vacuum degree in the scraper vacuum cavity. In an embodiment, the main controller is, for example, an industrial personal computer, a PLC, an MCU, a microprocessor, an FPGA, an ARM, a DSP, or a single chip microcomputer.

In an embodiment, the main controller prestores a threshold range, wherein the threshold range is determined by a target threshold, and the target threshold is a pressure value in a scraper vacuum cavity or a liquid level height value in the scraper vacuum cavity; correspondingly, the vacuum degree information in the scraper vacuum cavity is a pressure value in the scraper vacuum cavity or a liquid level height value in the scraper vacuum cavity. In an exemplary embodiment, the main controller may further set the threshold range through a display system of the host controller, for example, the threshold range in this embodiment is an air pressure target threshold range R, [ Q- δ, Q + δ ] (unit pa, negative), Q is a target threshold, δ is an adjustable range size value, and sends the R value to the main controller as an air pressure control target threshold range in the vacuum chamber of the scraper.

In one embodiment, the step of the main controller receiving vacuum degree information in the scraper vacuum chamber fed back by the sensor in real time and controlling the rotation speed of the vacuum pump according to the vacuum degree information to continuously adjust the vacuum degree in the scraper vacuum chamber includes matching the acquired vacuum degree information with a preset threshold range, and controlling the rotation speed of the vacuum pump according to a matching result to continuously adjust the vacuum degree in the scraper vacuum chamber so that the vacuum degree is maintained within the threshold range. In the embodiment, the main controller controls the vacuum pump to work, starts to pump air to the scraper vacuum cavity, and collects the pressure difference Q 'inside the scraper vacuum cavity fed back by the sensor in real time and compares the pressure difference Q' with the R value. In the embodiment shown in fig. 1, the vacuum box is located between the vacuum pump and the scraper vacuum chamber, so that the vacuum box has a buffering effect, prevents sudden change of air pressure in the scraper vacuum chamber, prevents resin from being sucked excessively, and protects the vacuum pump from being damaged. In this embodiment, the variation speed of the rotation speed of the vacuum pump is related to the difference between Q' -Q, and when the difference is large, the variation speed of the rotation speed is fast, otherwise, the variation speed is slow, and the purpose is to achieve the target value of the pressure difference quickly and to stably adjust the air pressure when the target value is close to the target value. The embodiment controls the change of the rotating speed of the vacuum pump according to the difference value between the measured differential pressure and the target threshold value, and can improve the working efficiency while ensuring the stability of the differential pressure.

In this embodiment, the step of controlling the rotation speed of the vacuum pump according to the matching result to continuously adjust the vacuum degree in the scraper vacuum chamber includes:

If the vacuum degree information in the scraper vacuum cavity acquired by the main controller is smaller than the lower threshold limit in the threshold range, namely Q' < Q-delta, the main controller controls the vacuum pump to increase the rotating speed; in an embodiment, the main controller is enabled to increase the rotation speed of the vacuum pump, and the feedback data of the sensor is read in real time.

And if the vacuum degree information in the scraper vacuum cavity acquired by the main controller is greater than the upper threshold limit in the threshold range, namely Q' > Q + delta, the main controller controls the vacuum pump to stop working and reads the feedback data of the sensor in real time.

And if the vacuum degree information in the scraper vacuum cavity acquired by the main controller is within a threshold range, namely Q' is the same as (Q-delta, Q + delta), the main controller controls the vacuum pump to keep the current rotating speed. In an embodiment, the main controller is enabled to maintain the rotating speed of the vacuum pump, and simultaneously obtain the feedback pressure difference inside the scraper vacuum cavity in real time; in an embodiment, the main controller is enabled to maintain the rotation speed of the vacuum pump, and read the feedback data of the sensor in real time.

The utility model provides a scraper stable system adopts main control unit to accept the scraper vacuum cavity inner vacuum degree information of sensor feedback, controls the vacuum pump according to the vacuum degree information of feedback and adjusts the rotational speed, comes real-time linear adjustment scraper vacuum degree through the regulation of vacuum pump rotational speed, and this adjustment is the continuity adjustment, can be faster, reach the threshold value that sets up steadily, ensures that the resin liquid level in the scraper vacuum cavity is stable, improves the quick shaping entity molding precision of plane light curing.

Referring to fig. 1, a schematic diagram of a principle architecture of the doctor blade stabilizing system of the present application in an embodiment is shown, and as shown in the diagram, in the embodiment shown in fig. 1, the doctor blade stabilizing system further includes a throttling device, the throttling device is disposed on a vacuum pumping pipeline between the vacuum pump and the vacuum cavity of the doctor blade, and the throttling device is electrically connected to the main controller and adjusts an air intake speed according to an instruction of the main controller. In an embodiment, the throttling device is a gas solenoid valve or a gas throttle valve.

In order to realize better regulation, the scraper stabilizing system further comprises a control box, wherein the control box is communicated with and arranged between the vacuum pump and the throttling device and used for caching sudden change of air pressure in the vacuum cavity of the scraper so as to prevent resin over-suction. The position of vacuum box in this embodiment plays the cushioning effect between vacuum pump and scraper vacuum cavity, prevents that the atmospheric pressure in the scraper vacuum cavity from taking place the sudden change to can prevent that the resin from cross inhaling, the protection vacuum pump is not damaged.

In this embodiment, the step of controlling the rotation speed of the vacuum pump according to the matching result to continuously adjust the vacuum degree in the scraper vacuum chamber includes:

And if the vacuum degree information in the scraper vacuum cavity acquired by the main controller is smaller than the lower threshold limit in the threshold range, namely Q' < Q-delta, the main controller controls the vacuum pump to increase the rotating speed and reads the feedback data of the sensor in real time.

And if the vacuum degree information in the scraper vacuum cavity acquired by the main controller is greater than the upper threshold limit in the threshold range, namely Q' > Q + delta, the main controller controls the throttling device to increase the air inlet speed and reduce the rotating speed of the vacuum pump, and reads the feedback data of the sensor in real time.

And if the vacuum degree information in the scraper vacuum cavity acquired by the main controller is within the threshold range, namely Q' is the same as (Q-delta, Q + delta), the main controller controls the vacuum pump to keep the current rotating speed and reads the feedback data of the sensor in real time.

To further illustrate the principles and efficacy of the present application, reference is made to fig. 2, which is a flow chart illustrating the operation of the doctor blade stabilizing system of the present application in one embodiment, and as shown, the main controller of the doctor blade stabilizing system includes the following steps:

1) Presetting a threshold range related to the vacuum degree of the scraper in the main controller; the threshold range can be determined by setting a minimum threshold value and a maximum threshold value, or a target threshold value can be set firstly, and then an adjustable range size value is designated, and in any form, the set threshold range is only required to be combined with actual requirements; in an embodiment, the threshold range is determined by a target threshold, for example, a pressure value in the blade vacuum chamber or a height value of a liquid level in the blade vacuum chamber.

in order to obtain the vacuum degree in the scraper vacuum cavity conveniently, the sensors can be a pressure sensor, a differential pressure sensor, a displacement sensor and a position sensor, namely the vacuum degree information can be a pressure value in the scraper vacuum cavity and can also be a liquid level height value in the scraper vacuum cavity. The selection of the sensor is consistent with the parameters corresponding to the threshold range, and if the sensor is a pressure sensor, the threshold range is a pressure range value.

2) The main controller acquires vacuum degree information in a scraper vacuum cavity detected by the sensor in real time; the vacuum degree information can be a pressure value in the scraper vacuum cavity or a liquid level height value in the scraper vacuum cavity, and the vacuum degree information can only represent the vacuum degree in the scraper vacuum cavity;

3) The main controller matches the acquired vacuum degree information with the threshold range and controls the rotation speed of the vacuum pump according to the matching result; and simultaneously, reading feedback data of the sensor in real time. In an embodiment, the main controller specifically controls the rotation speed of the vacuum pump by: if the acquired vacuum degree information in the scraper vacuum cavity is smaller than the lower threshold limit in the threshold range, the main controller controls the vacuum pump to increase the rotating speed, if the acquired vacuum degree information in the scraper vacuum cavity is larger than the upper threshold limit in the threshold range, the main controller controls the vacuum pump to stop working when no throttling device exists, and increases the air inlet speed of the throttling device and reduces the rotating speed of the vacuum pump when the throttling device exists; and if the acquired vacuum degree information in the scraper vacuum cavity is within the threshold range, the main controller controls the vacuum pump to keep the current rotating speed.

4) And 3) the vacuum pump works according to the control command sent by the main controller in the step 3), so that the vacuum degree in the scraper vacuum cavity is kept within the threshold range.

In an embodiment, the control of the vacuum pump gas flow rate comprises: the change speed of the gas flow rate is related to the difference between the feedback value and the target value of the sensor, and the larger the difference is, namely the difference between the feedback value and the target value of the sensor is larger, the change speed of the gas flow rate is larger; the smaller the difference, i.e., the closer to the target value, the smaller the rate of change of the gas flow rate.

In order to realize better adjustment, a vacuum box and a throttling device are further arranged on a vacuum pumping pipeline between the vacuum pump and the scraper vacuum cavity, the throttling device is communicated with an external space, and in the step 3), the main controller controls the throttling device simultaneously according to a matching result. The throttling device can be a gas electromagnetic valve or a gas throttling valve.

The scraper stabilization system in this application includes a scraper, a sensor, a throttling device and a main controller. The sensor is communicated with the scraper vacuum cavity; one end of the throttling device is connected with the external space, and the other end of the throttling device is connected with the vacuum box; the main controller is used for comparing the feedback value with the target threshold value and adjusting the vacuum pump and the throttling device correspondingly. In different embodiments, the main controller can be an industrial personal computer, a PLC, an MCU, a microprocessor, an FPGA, an ARM, a DSP and a single chip microcomputer. In different embodiments, the vacuum pump may be of the suction type or of the blowing type.

This application adopts main control unit to accept the scraper vacuum cavity inner vacuum degree information of sensor feedback, controls the vacuum pump according to the vacuum degree information of feedback and adjusts the rotational speed, adjusts the scraper vacuum degree in real time through the regulation of vacuum pump rotational speed, and this adjustment is the continuity adjustment, can reach the threshold value that sets up more fast, steadily, ensures that the resin liquid level in the scraper vacuum cavity is stable, improves the quick shaping entity of plane photocuring molding precision.

The application further provides a method for controlling the vacuum degree of the scraper, and in an exemplary embodiment, assuming that preparation work of a resin tank, an optical system and a coating device of a 3D printing device is completed, the method enters an initial stage of workpiece (printing), and the method for controlling the vacuum degree of the scraper comprises the following steps:

1) Starting a throttling device; in the embodiment, the throttling device is activated to make the gas flow rate of the throttling device at a lower level, and as will be understood by those skilled in the art, the lower level is an operating state in which the throttling device is communicated with the external space and is not controlled by the main controller, and the lower level is an initial operating state of the throttling device.

2) Setting a threshold range, wherein the threshold range comprises a target threshold; in an embodiment, a threshold range is set through a display system of a host controller and stored in the host controller, the threshold range in this embodiment is an air pressure target threshold range R, [ Q- δ, Q + δ ] (unit pa, which is a negative value), Q is a target threshold, δ is an adjustable range size value, and the R value is sent to the host controller as an air pressure control target threshold range in a scraper vacuum chamber.

3) Controlling a vacuum pump to pump air into the scraper vacuum cavity by a main controller, and simultaneously enabling the main controller to acquire the fed back pressure difference inside the scraper vacuum cavity in real time and compare the pressure difference with the target threshold value; in the embodiment, the main controller controls the vacuum pump to work, starts to pump air to the scraper vacuum cavity, and collects the pressure difference Q 'inside the scraper vacuum cavity fed back by the sensor in real time and compares the pressure difference Q' with the R value. In the embodiment shown in fig. 1, the vacuum box is located between the vacuum pump and the scraper vacuum chamber to play a role in buffering, prevent sudden change of air pressure in the scraper vacuum chamber, prevent resin from being excessively sucked and protect the vacuum pump from being damaged. In this embodiment, the variation speed of the rotation speed of the vacuum pump is related to the difference between Q' -Q, and when the difference is large, the variation speed of the rotation speed is fast, otherwise, the variation speed is slow, and the purpose is to achieve the target value of the pressure difference quickly and to stably adjust the air pressure when the target value is close to the target value. The embodiment controls the change of the rotating speed of the vacuum pump according to the difference value between the measured differential pressure and the target threshold value, and can improve the working efficiency while ensuring the stability of the differential pressure.

4) in the embodiment, if the feedback value Q' epsilon (Q-delta, Q + delta) of the differential pressure sensor is within the allowable range, the step 5 is carried out; if Q '< Q-delta, go to step 6), if Q' > Q + delta, go to step 7).

5) when the pressure difference in the scraper vacuum cavity is within the threshold range, namely Q' epsilon (Q-delta, Q + delta), enabling the main controller to keep the rotating speed of the vacuum pump, and simultaneously acquiring the feedback pressure difference in the scraper vacuum cavity in real time; in an embodiment, the main controller is enabled to maintain the rotating speed of the vacuum pump, and read the feedback value of the sensor in real time, and return to the step 2).

6) When the pressure difference level inside the scraper vacuum cavity is smaller than the lower threshold of the threshold range, namely Q' < Q-delta, the main controller controls the vacuum pump to increase the rotating speed; in an embodiment, the main controller is caused to increase the rotational speed of the vacuum pump; reading the feedback value of the sensor in real time, and returning to the step 3);

7) When the pressure difference level inside the scraper vacuum cavity is larger than the upper threshold limit of the threshold range, namely Q' > Q + delta, the main controller controls the throttling device to increase the air inlet speed and reduce the rotating speed of the vacuum pump. In an embodiment, the main controller appropriately reduces the rotation speed of the vacuum pump, appropriately increases the air flow speed of the throttling device, reads the feedback value of the sensor in real time, and returns to the step 3).

8) And (5) repeating the steps 3) -7) at the gap in the workpiece making process to ensure that the liquid level in the scraper vacuum cavity is stable until the whole workpiece making process is finished. The scraper vacuum degree control method is a continuous or linear air pressure control method, and air pressure cannot jump, so that the pressure of a scraper vacuum inner cavity is more stable.

To sum up, the scraper stable system of this application, it adopts main control unit to accept the scraper vacuum cavity inner vacuum degree information of sensor feedback, controls the vacuum pump according to the vacuum degree information of feedback and adjusts the rotational speed, adjusts the scraper vacuum degree in real time through the regulation of vacuum pump rotational speed, and this adjustment is the linear adjustment of continuity, can reach the threshold value that sets up more fast, steadily, ensures that the resin liquid level in the scraper vacuum cavity is stable, improves the quick shaping entity molding precision of plane photocuring. Therefore, the application effectively overcomes various defects in the prior art and has high industrial utilization value.

The above embodiments are merely illustrative of the principles and utilities of the present application and are not intended to limit the application. Any person skilled in the art can modify or change the above-described embodiments without departing from the spirit and scope of the present application. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical concepts disclosed in the present application shall be covered by the claims of the present application.