Negative pressure discharging mechanism and 3D printer having the same

Abstract

The present invention relates to the field of 3D printing technology, and particularly designs a 3D printer, which consists of a frame, an X-axis driving mechanism, a Y-axis driving mechanism, a Z-axis driving mechanism, a hot bed and a negative pressure discharging mechanism. The negative pressure discharging mechanism of the present invention utilizes negative pressure to convey granular consumables, thereby avoiding the problem of the consumables breaking during the printing process and causing the printing to be terminated. At the same time, the waste heat of the heated consumables is recovered to preheat the consumables, thereby also having the advantage of heat energy recovery.

Description

Technical Field

[0001] The present invention relates to the technical field of 3D printers, and in particular to a negative pressure discharge mechanism and a 3D printer having the mechanism. Background Art

[0002] 3D printers are devices used for rapid prototyping. Currently, they are mainly based on digital model files and use meshing materials such as powdered metal or plastic to construct objects generally by printing layer by layer.

[0003] At present, the structure of 3D printers mainly consists of a print head (discharge mechanism for discharging materials), a heated bed (for receiving materials), and an X-axis moving mechanism, a Y-axis moving mechanism, and a Z-axis moving mechanism for driving the print head and / or the heated bed to move. The movement of the print head or the heated bed is controlled in three dimensions by the X-axis moving mechanism, the Y-axis moving mechanism, and the Z-axis moving mechanism to complete the object construction work (i.e., 3D printing work).

[0004] At present, the consumables of 3D printers are mainly in filament form. The filamentary consumables are fed into the print head, heated and melted by the print head, and then sprayed from the print head to the hot bed to complete the 3D printing work. However, since the filamentary consumables require continuity, that is, during the printing process, if the filamentary consumables break, the printing process will be terminated. Therefore, there is a disadvantage of inconvenience in use.

[0005] Secondly, when the print head heats the consumables, the excess heat energy generated by the heater is usually discharged by the fan and cannot be reused, so there is a waste of energy.

[0006] In summary, necessary improvements need to be made to existing 3D printers. Summary of the invention

[0007] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a negative pressure discharge mechanism and a 3D printer having the mechanism, aiming to solve the problems arising from the above-mentioned background technology.

[0008] The technical solution of the present invention is implemented as follows: a 3D printer is composed of a frame, an X-axis driving mechanism, a Y-axis driving mechanism, a Z-axis driving mechanism, a hot bed and a negative pressure discharge mechanism.

[0009] The negative pressure discharge mechanism and the hot bed of the present invention complete the 3D printing work under the control of the X-axis drive mechanism, the Y-axis drive mechanism and the Z-axis drive mechanism. Different from the prior art, the consumables of the 3D printer of the present invention are granular rather than filamentary, which effectively avoids the situation in which the filamentary consumables break during the printing process and causes the printing work to be suspended.

[0010] More specifically, the negative pressure discharging mechanism of the present invention includes, in order of discharging, the following:

[0011] Storage module;

[0012] Negative pressure module;

[0013] A heating module having a discharge end;

[0014] Wherein, the negative pressure module at least has a material negative pressure chamber and an airflow negative pressure chamber, and the material negative pressure chamber and the airflow negative pressure chamber can be controlled to form negative pressure in turn;

[0015] When the material negative pressure chamber forms a negative pressure, the material in the material storage module is sent into the material negative pressure chamber, and when the material negative pressure chamber is restored, the material is sent into the heating module;

[0016] When the negative pressure chamber forms a negative pressure, outside air is introduced into the negative pressure chamber to recover the waste heat of the heating module. When the negative pressure chamber is restored, the hot air is sent to the material storage module to preheat the material.

[0017] By adopting the above technical solution:

[0018] The negative pressure discharge mechanism of the present invention controls the feeding of the granular consumables, and during feeding, it can recover the heat generated by the heating module, and this part of the heat is recovered to preheat the granular consumables in the storage module, so that when the granular consumables enter the heating module, they can be heated faster (this can shorten the discharge end stroke) and ejected, thereby improving printing efficiency;

[0019] The material storage module in the present invention is used for storing granular consumables. When the negative pressure module forms negative pressure, the granular consumables are extracted from the material storage module and further sent to the heating module for subsequent printing work.

[0020] Furthermore, the negative pressure module of the present invention comprises:

[0021] A negative pressure body, having at least two negative pressure chambers therein;

[0022] At least two movable blocks are controlled to move in each negative pressure chamber, and each negative pressure chamber is divided into the material negative pressure chamber and the airflow negative pressure chamber;

[0023] The air intake structure and the air exhaust structure are arranged on the negative pressure body and can be communicated with the airflow negative pressure cavity and can control the unidirectional flow of gas;

[0024] At least two driving rods are connected to each movable block and one end of the driving rods passes through the negative pressure body;

[0025] The driving structure is installed on one side of the negative pressure body and can control the reciprocating motion of each driving rod;

[0026] When the driving structure controls the driving rod to move and expands the material negative pressure chamber or the airflow negative pressure chamber, negative pressure is formed in the material negative pressure chamber or the airflow negative pressure chamber.

[0027] By adopting the above technical solution:

[0028] The negative pressure module of the present invention is provided with at least two negative pressure chambers, and each negative pressure chamber can alternately "draw materials" from the material storage module, thereby ensuring the continuity of the heating module spraying materials and ensuring the printing efficiency.

[0029] Furthermore, the driving structure includes:

[0030] A driving box is installed on one side of the negative pressure body;

[0031] The lifting platform can be controlled by electric struts to move up and down in the drive box;

[0032] The transmission shaft is rotatably mounted on the lifting platform and can be driven to rotate by the motor;

[0033] At least two drive wheels are installed on the transmission shaft at intervals;

[0034] Wherein, the driving wheel and the driving rod are provided with meshing tooth structures that can mesh with each other.

[0035] Furthermore, the heating module comprises:

[0036] A discharge pipe is installed on the negative pressure body and is connected to the negative pressure chamber of the material;

[0037] The nozzle is installed on the discharge pipe;

[0038] A heater is installed on the discharge pipe and is used to heat the discharge pipe;

[0039] The air intake structure is composed of an air intake pipe which is arranged on the negative pressure body and led to the heater, and a one-way valve which is arranged on the air intake pipe.

[0040] Furthermore, the exhaust structure includes:

[0041] An exhaust pipe is arranged on the negative pressure body, is communicated with the airflow negative pressure chamber, and is provided with a one-way valve;

[0042] The support body is supported by the exhaust pipe and is recessed on a side away from the exhaust pipe;

[0043] The movable body cooperates with the supporting body and can rotate and move on the supporting body;

[0044] A connecting pipe, mounted on the movable body;

[0045] Wherein, an air cavity connected with the exhaust pipe and the connecting pipe is formed between the supporting body and the movable body.

[0046] Furthermore, the storage module comprises:

[0047] A material storage body is installed on the negative pressure body and has a material storage cavity;

[0048] The material discharge chamber is arranged between the material storage body and the negative pressure body, and is connected with the material storage chamber and the material negative pressure chamber;

[0049] The heat exchange body is coaxially sleeved on the material storage body and can contact the material storage body, and has a limit tube that can be detachably connected to the connecting tube;

[0050] Wherein, the heat exchange body is provided with a heat exchange cavity which is connected with the limiting pipe.

[0051] Further: the negative pressure body is provided with a rotating structure, wherein the rotating structure includes;

[0052] The rotating shaft is rotatably arranged on the negative pressure body, and the two ends thereof extend toward the discharge pipe and the storage cavity respectively;

[0053] An anti-blocking rod is installed on the rotating shaft and located in the discharge pipe;

[0054] A linkage shaft is detachably disposed on the rotating shaft and connected to the heat exchange body;

[0055] Wherein, the heat exchange body is composed of a rotating body connected to the linkage shaft and an air inlet arranged on the inner wall of the rotating body and capable of contacting the outer wall of the storage body;

[0056] The outer wall of the material storage body is concavely provided with a plurality of spacing grooves which are distributed at intervals and can separate the material storage body from the intake air.

[0057] Furthermore, a gear located between the negative pressure chambers is provided on the rotating shaft, and a control structure for driving the gear to rotate is provided on the movable block, and the control structure includes:

[0058] The control groove is recessed and arranged on the side of the movable block close to the gear;

[0059] The through cavity penetrates the movable block and is communicated with the control groove;

[0060] A rack is installed in the control groove through a first spring;

[0061] A support rod connected to the rack, extending through the through cavity and contacting the cavity wall of the negative pressure cavity;

[0062] The cavity wall of the negative pressure cavity is formed with a driving surface for the end of the support rod to move. When the end of the support rod slides on the driving surface, the rack and the gear are engaged or separated.

[0063] Furthermore, an air extraction cavity is formed on the negative pressure body, an exhaust channel connected to the air extraction cavity is formed in the negative pressure body, and a central heat exchange cavity connected to the exhaust channel and having a top penetrating therethrough is formed in the rotating shaft and the linkage shaft;

[0064] Wherein, a pumping structure is provided in the pumping cavity, and the pumping structure is composed of a pumping body and a second spring, the pumping body is connected to the pumping cavity through the second spring, and a linkage rod penetrating into the pumping cavity is provided on the movable block, and a matching groove for the linkage rod to move is provided on a side of the pumping body close to the movable block;

[0065] The negative pressure body is also provided with an air suction structure communicated with the air suction cavity.

[0066] The beneficial effects of the present invention are at least:

[0067] 1. Compared with the prior art, the present invention uses granular consumables for 3D printing. The negative pressure material extraction and feeding method can smoothly complete the feeding of consumables without breaking, thus ensuring the continuity of printing.

[0068] 2. During 3D printing, the present invention can not only utilize the negative pressure module to feed materials, but also absorb the heat energy generated by the heating module through the negative pressure module, and send this part of the heat energy to the material storage module to preheat the materials in the material discharging module, thereby achieving the purpose of energy recovery and reuse;

[0069] 3. Based on point 2, the present invention can preheat the storage module by selecting different modes based on the consumables of different particle sizes, which at least includes:

[0070] Peripheral heating: hot air is sent into the heat exchanger, and the heat exchanger is used to preheat the consumables from the outside to the inside. It is generally suitable for consumables with larger particle sizes.

[0071] Peripheral and internal heating: The hot air is not only sent into the heat exchange body, but also sent into the central heat exchange cavity through the vacuum cavity. Therefore, the consumables in the storage module can be preheated from the inside out and from the outside in. It is suitable for consumables with smaller particle sizes (consumables with smaller particle sizes are denser in the storage module, so the preheating requirements cannot be met by only peripheral preheating);

[0072] 4. In the present invention, in order to avoid the consumables from melting in the storage module when preheating the consumables, the present invention uses a spacing groove to separate the heat exchange body and the storage body at intervals, which can not only ensure preheating, but also avoid the consumables from melting in the storage body due to continuous preheating.

[0073] 5. In the present invention, the negative pressure chamber, the air extraction chamber and the heat exchange body are all controlled by a driving structure, which reduces the overall volume of the negative pressure discharge mechanism and also ensures the synchronization of the operation of the components controlled by the driving structure.

[0074] In addition, other advantages of the present invention will be shown in the embodiment of the present invention, thereby making the beneficial effects of the present invention more significant. BRIEF DESCRIPTION OF THE DRAWINGS

[0075] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0076] Figure 1 It is a structural schematic diagram of a specific embodiment 1 of the present invention;

[0077] Figure 2 It is a structural schematic diagram of a specific embodiment 1 of the present invention without part of the chassis;

[0078] Figure 3 It is a structural schematic diagram of the negative pressure discharging mechanism in the specific embodiment 1 of the present invention;

[0079] Figure 4 It is a cross-sectional view of the negative pressure discharging mechanism in the specific embodiment 1 of the present invention;

[0080] Figure 5 It is a structural schematic diagram of the negative pressure discharge module in specific embodiment 2 of the present invention;

[0081] Figure 6 for Figure 5 AA section view in;

[0082] Figure 7 for Figure 5 The enlarged view of the F part in the figure;

[0083] Figure 8 for Figure 5 BB section view in;

[0084] Fig. 9 It is a schematic diagram of another driving mode of the driving structure in the specific embodiment 2 of the present invention. DETAILED DESCRIPTION

[0085] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0086] Example 1

[0087] like Figure 1-4 As shown, the present invention discloses a 3D printer, which consists of a frame (consisting of a chassis 10 and a frame body 11, and the frame body 11 is installed in the chassis 10), an X-axis driving mechanism 13, a Y-axis driving mechanism 14, a Z-axis driving mechanism 15, a hot bed 12 and a negative pressure discharge mechanism 2.

[0088] In this embodiment, the X-axis drive mechanism, the Y-axis drive mechanism, and the Z-axis drive mechanism are all screw rod structures;

[0089] More specifically, the hot bed 12 is mounted on the Z-axis driving mechanism, and the hot bed 12 is mounted on the frame 11 by means of a slide 120, and is slidably connected to the frame 11, and is controlled by the Z-axis driving mechanism to perform lifting (Z-direction) activities;

[0090] The negative pressure discharge mechanism 2 is mounted on the X-axis drive mechanism 13 and is controlled by the X-axis drive mechanism 13 to move in the X direction;

[0091] The X-axis driving mechanism 13 is controlled by the Y-axis driving mechanism 14 to move in the Y direction by means of the screw bearing seat 140 on the Y-axis driving mechanism 14;

[0092] Therefore, during 3D printing, the X-axis drive mechanism controls the negative pressure discharge mechanism to move in the X direction, and the Y-axis drive mechanism controls the X-axis drive mechanism to move in the Y direction, so that a plane printing work can be completed. After the first layer of printing is completed, the Z-axis drive mechanism controls the hot bed to descend, thereby completing the layer-by-layer printing work.

[0093] At present, the three-dimensional driving mechanism of the 3D printer (ie, the X-axis driving mechanism 13, the Y-axis driving mechanism 14, and the Z-axis driving mechanism 15) is a relatively mature existing technology. Therefore, in this embodiment, the structure, principle, and operation mode of the three-dimensional driving mechanism are not described in detail.

[0094] The present embodiment is a negative pressure discharging mechanism, which is different from the prior art. The negative pressure discharging mechanism 2 of the present embodiment includes the following in order of discharging:

[0095] Storage module 21;

[0096] Negative pressure module 22;

[0097] The heating module 23 has a discharge end;

[0098] Wherein, the negative pressure module at least has a material negative pressure chamber 22a and an airflow negative pressure chamber 22b, and the material negative pressure chamber 22a and the airflow negative pressure chamber 22b can be controlled to form negative pressure in turn;

[0099] When the negative pressure chamber 22a of the material forms a negative pressure, the material in the material storage module 21 is sent into the negative pressure chamber 22a of the material, and when the negative pressure chamber 22a of the material is restored, the material is sent into the heating module 23;

[0100] When negative pressure is formed in the negative pressure airflow chamber 22b, outside air is introduced into the negative pressure airflow chamber 22b to recover the waste heat of the heating module 23. When the negative pressure airflow chamber 22b is restored, the hot air is sent to the material storage module 21 to preheat the material.

[0101] In this embodiment, the negative pressure module 22 is composed of a negative pressure body 220 and a movable block 221 arranged in the negative pressure body. The negative pressure body 220 is divided into a material negative pressure chamber 22a and an airflow negative pressure chamber 22b by the movable block 221, and the movable block 221 is controlled by a driver 222 (such as: a cylinder, an electric push rod, etc.) to move in the negative pressure body 220.

[0102] In this embodiment, the material storage module 21 is a material storage barrel 210 installed on one side of the negative pressure body 220 for storing granular consumables.

[0103] In this embodiment, the heating module 23 is composed of a heating tube 230 installed on the negative pressure body 220 , a nozzle 231 provided at the end of the heating tube 230 , and a heater 232 installed on the heating tube 230 .

[0104] In this embodiment, a return air portion 223 is disposed on the negative pressure body 220 , and a return air channel 224 with an air inlet end located at the periphery of the heater 232 is disposed on the return air portion 223 .

[0105] In this embodiment, a one-way valve 24 is provided at the connection point between the material negative pressure chamber 22a and the heating cylinder 230, the connection point between the material negative pressure chamber 22a and the storage barrel 210, the connection point between the return air channel 224 and the airflow negative pressure chamber 22b, and the connection point between the airflow negative pressure chamber 22b and the storage barrel 210 to ensure the unidirectional movement of the granular consumables from the storage barrel, the material negative pressure chamber and the heating cylinder, and at the same time, to ensure the unidirectional flow of the airflow from the return air channel 224, the gas negative pressure chamber 22b and the storage barrel.

[0106] refer to Figure 1-4When the negative pressure discharge mechanism of this embodiment is in use, the granular consumables are poured into the storage barrel, and the movable block is controlled by the driver 222 to move in the negative pressure body. When the volume of the material negative pressure chamber expands, the material negative pressure chamber forms a negative pressure, and the consumables in the storage barrel enter the material negative pressure chamber. When the volume of the material negative pressure chamber decreases, the movable block squeezes the consumables from the material negative pressure chamber into the heating barrel, and is heated by the heating barrel and ejected from the nozzle. After the consumables are sprayed onto the hot bed, 3D printing is performed.

[0107] Similarly, when the volume of the airflow negative pressure chamber expands, the airflow negative pressure chamber forms a negative pressure and absorbs the waste heat around the heater through the return air channel. When the volume of the airflow negative pressure chamber shrinks, the movable block squeezes the hot air from the airflow negative pressure chamber into the storage barrel to complete the preheating of the consumables, thereby achieving the purpose of recovering heat energy.

[0108] Embodiment 2 is different from Embodiment 1 in that:

[0109] To ensure the continuity of 3D printing, refer to Figure 5-9 , the negative pressure module 22 of the present invention comprises:

[0110] The negative pressure body 220 is provided with at least two negative pressure chambers;

[0111] At least two movable blocks 30 are controlled to move in each negative pressure chamber, and each negative pressure chamber is divided into the material negative pressure chamber 22a and the airflow negative pressure chamber 22b;

[0112] The air intake structure and the air exhaust structure are arranged on the negative pressure body 220 and can be communicated with the airflow negative pressure chamber 22b, and can control the unidirectional flow of gas;

[0113] At least two driving rods 31 are connected to each movable block 30, and one end of the driving rods 31 passes through the negative pressure body;

[0114] The driving structure is installed on one side of the negative pressure body 220 and is capable of controlling the reciprocating motion of each driving rod 31;

[0115] When the driving structure controls the driving rod 31 to move and expand the material negative pressure chamber 22a or the airflow negative pressure chamber 22b, negative pressure is formed in the material negative pressure chamber 22a or the airflow negative pressure chamber 22b.

[0116] In this embodiment, the driving structure includes:

[0117] The driving box 40 is installed on one side of the negative pressure body 220;

[0118] The lifting platform 41 can be controlled by the electric support rod 42 to move up and down in the driving box 40;

[0119] The transmission shaft 43 is rotatably mounted on the lifting platform 41 and can be driven to rotate by the motor 44;

[0120] At least two driving wheels 45 are installed on the transmission shaft 43 at intervals;

[0121] The driving wheel 45 and the driving rod 31 are provided with meshing tooth structures 46 that can mesh with each other.

[0122] In this embodiment, the heating module 23 includes:

[0123] The discharge pipe 50 is installed on the negative pressure body 220 and communicates with the material negative pressure chamber 22a;

[0124] The nozzle 51 is installed on the discharge pipe 50;

[0125] A heater 52 is installed on the discharge pipe 50 and is used to heat the discharge pipe 50;

[0126] The air intake structure is composed of an air intake pipe arranged on the negative pressure body 220 and led to the heater 52, and a one-way valve 55 arranged on the air intake pipe (used to ensure that the gas can only flow in one direction from the air intake pipe to the airflow negative pressure chamber).

[0127] In this embodiment, the air intake pipe includes a first tube body 540 (with a gap between it and the heater 52) which is coaxially arranged with the heater 52 and a second tube body 541 which is connected to the first tube body 540. The inner circle of the first tube body 540 (the side close to the heater 52) is provided with an air intake cavity 542 which is connected to the second tube body 541. That is to say, when negative pressure is formed in the airflow negative pressure cavity 22b, the one-way valve 55 on the second tube body is opened, and the hot air around the heater 52 is recovered through the air intake cavity 542.

[0128] In this embodiment, the exhaust structure includes:

[0129] The exhaust pipe 60 is provided on the negative pressure body 220 and communicates with the airflow negative pressure chamber 22b and is provided with a one-way valve 55;

[0130] The support body 61 is supported by the exhaust pipe 60 (the support body 61 and the exhaust pipe 60 are integrally formed) and is recessed away from the exhaust pipe 60;

[0131] The movable body 62 cooperates with the supporting body 61 and can rotate and move on the supporting body 61;

[0132] A connecting pipe 63 is mounted on the movable body 62;

[0133] An air cavity 65 communicating with the exhaust pipe 60 and the connecting pipe 63 is formed between the supporting body 61 and the movable body 62 .

[0134] In this embodiment, the storage module 21 includes:

[0135] The material storage body 70 is installed on the negative pressure body 220 and has a material storage cavity 71;

[0136] The material discharge chamber is provided between the material storage body 70 and the negative pressure body 220 (the material storage body 70 and the negative pressure body 220 are integrally formed, and the material discharge chamber is formed between the material storage body 70 and the negative pressure body 220), and communicates with the material storage chamber 71 and the material negative pressure chamber 22a, and a one-way valve 55 is provided in the material discharge chamber;

[0137] The heat exchange body 72 is coaxially sleeved on the storage body 70 and can contact the storage body 70, and has a limit tube 73 that can be detachably connected to the connecting tube 63, one end of the limit tube 73 is out of the connecting tube 63, and is installed by a bolt 73a that penetrates the limit tube 73 and the connecting tube 63;

[0138] The heat exchange body 72 is provided with a heat exchange cavity 72 a which is in communication with the limiting tube 73 .

[0139] In this embodiment, a rotating structure is provided on the negative pressure body, wherein the rotating structure includes:

[0140] The rotating shaft 80 is rotatably disposed on the negative pressure body 220, and two ends thereof extend toward the discharge pipe 50 and the storage chamber 71 respectively;

[0141] The anti-blocking rod 81 is mounted on the rotating shaft 80 and is located in the discharge pipe 50;

[0142] The linkage shaft 82 is detachably disposed on the rotating shaft 80 and connected to the heat exchange body 72. The matching surfaces of the linkage shaft 82 and the rotating shaft 80 are provided with mutually matching limiting ribs 80b and limiting grooves. The limiting ribs 80b enable the linkage shaft to rotate with the rotating shaft 80.

[0143] The heat exchange body 72 is composed of a rotating body 720 connected to the linkage shaft 82 and an air inlet 721 disposed on the inner wall of the rotating body 720 and capable of contacting the outer wall of the storage body 70;

[0144] The outer wall of the storage body 70 is recessed to form a plurality of spacing grooves 70 a which are spaced apart and can separate the storage body 70 from the intake air 721 .

[0145] In this embodiment, the rotating shaft 80 is provided with a gear 90 located between the negative pressure chambers, and the movable block is provided with a control structure for driving the gear 90 to rotate, and the control structure includes:

[0146] The control groove 91 is recessed and arranged on the side of the movable block 30 close to the gear 90;

[0147] The through cavity 92 penetrates the movable block 30 and communicates with the control groove 91;

[0148] The rack 93 is installed in the control groove 91 through the first spring 94;

[0149] A support rod 95 connected to the rack 93 and extending through the through cavity 92 and contacting the cavity wall of the negative pressure cavity;

[0150] The wall of the negative pressure chamber is formed with a driving surface 96 for the end of the support rod 95 (the end of the support rod 95 is provided with a universal ball 95a) to move. When the end of the support rod 95 slides on the driving surface 95, the rack 93 is engaged or disengaged with the gear 90.

[0151] In this embodiment, an air extraction cavity 97 is further formed on the negative pressure body, an exhaust passage 98 communicating with the air extraction cavity 97 is formed in the negative pressure body 220, and a central heat exchange cavity 99 communicating with the exhaust passage 98 and having a top penetrating therethrough is formed in the rotating shaft 80 and the linkage shaft 82, that is, an air inlet 80a communicating with the exhaust passage 98 is provided on the rotating shaft 80;

[0152] The pumping cavity 97 is provided with a pumping structure, which is composed of a pumping body 97a and a second spring 97b. The pumping body 97a is connected to the pumping cavity 97 through the second spring 97b, and a linkage rod 97c penetrating into the pumping cavity 97 is provided on the movable block 30. A matching groove 97d for the linkage rod 97c to move is provided on the side of the pumping body 97a close to the movable block 30. When the linkage rod 97c and the pumping body 97a are abutted against each other and continue to move in the direction of the second spring 97b, the pumping body 97a can be driven to move in the pumping cavity 97. When the linkage rod is separated from the pumping body, the pumping body is driven by the second spring to move in the direction of the movable block.

[0153] The negative pressure body 220 is also provided with an air suction structure connected to the air suction chamber 97 , and the air suction structure is composed of an air suction pipe 56 installed on the second tube body 541 of the air inlet pipe and a one-way valve 55 provided on the air suction pipe 56 .

[0154] refer to Figure 5-9 , the principle of this embodiment is:

[0155] Discharging principle: reference Figure 5-6 , the driving structure is started, the driving wheel is controlled to rotate by the motor, and the driving rod meshing with the driving wheel through the meshing tooth structure is driven to move. When the driving rod moves, the movable block in the negative pressure chamber moves accordingly, and a negative pressure is formed in the material negative pressure chamber or the gas negative pressure chamber. When a negative pressure is formed in the material negative pressure chamber, the one-way valve in the discharge chamber is opened, and the consumables in the storage chamber enter the material negative pressure chamber through the discharge chamber. When the movable block moves and the volume of the material negative pressure chamber is reduced, the consumables in the material negative pressure chamber are squeezed into the discharge pipe, and after being heated by the heater outside the discharge pipe, the consumables are ejected from the nozzle to complete the discharge.

[0156] It is worth noting that a one-way valve is also provided at the discharge end of the material negative pressure chamber. Therefore, when the movable block moves, it can ensure that the consumables enter the material negative pressure chamber from the storage chamber through the discharge chamber, and can also make the consumables in the material negative pressure chamber be squeezed into the discharge pipe.

[0157] Heat recovery principle: reference Figure 5-8 In this embodiment, driven by the driving structure, the movable block reciprocates in the negative pressure chamber. When the movable block moves, the airflow negative pressure chamber and the material negative pressure chamber generate negative pressure alternately. When the material negative pressure chamber generates negative pressure, the material negative pressure chamber is fed, and when the airflow negative pressure chamber generates negative pressure, the material negative pressure chamber is discharged, and at the same time, the airflow negative pressure chamber starts to take in air. In more detail:

[0158] When negative pressure is formed in the airflow negative pressure chamber, air is sucked in through the first tube body of the air intake structure, and when the movable block drives the volume of the airflow negative pressure chamber to shrink, the gas is squeezed out and sent into the heat exchange chamber of the heat exchanger through the exhaust structure. When the heat exchanger contacts the storage body, the consumables in the storage body are preheated, thereby achieving the purpose of heat energy recovery.

[0159] It is worth noting that: in this embodiment, both the air intake structure and the exhaust structure are provided with one-way valves, so that the airflow can be ensured to flow in one direction from the air intake mechanism, the airflow negative pressure chamber, the exhaust structure and the heat exchange chamber.

[0160] In this embodiment, the air suction structure and the exhaust channel connected to the air suction cavity are also provided with a one-way valve to ensure that the air flow flows in one direction from the air suction structure, the air suction cavity and the exhaust channel.

[0161] In this embodiment, in order to adapt to the preheating of consumables of different particle sizes, two modes are set, as follows:

[0162] In the first mode, it is suitable for consumables with smaller particle sizes. Such consumables are more fully accumulated in the storage cavity. Therefore, the effect of preheating only the outer wall of the storage body is poor. Therefore, this embodiment can preheat the storage body from the inside out and from the outside in. Figure 5-8In this embodiment, the electric strut controls one of the driving wheels to mesh with the driving rod. The driving wheel has two groups of meshing teeth, which are symmetrically arranged with equal circumferential spacing, and the number of meshing teeth of each meshing tooth structure of the driving wheel is large, so that the driving rod can be controlled to have a longer single movement stroke, so that the movable block can touch the pumping gas in the pumping chamber when it moves. At this time, when the movable body approaches and pushes the pumping gas, the gas in the pumping chamber and the gas in the airflow negative pressure chamber can be squeezed out, and when the movable body is away from the pumping gas, then The vacuum chamber and the airflow negative pressure chamber generate negative pressure at the same time, the airflow negative pressure chamber supplies air to the heat exchanger, and the airflow in the vacuum chamber enters the exhaust channel of the negative pressure body, and enters the central heat exchange chamber through the air inlet arranged on the rotating shaft, and preheats the consumables in the storage body from the center of the storage body to the outside (and is discharged from the top of the central heat exchange chamber after preheating), and the hot air discharged from the airflow negative pressure chamber enters the heat exchanger, and preheats the consumables in the storage body from the outside of the storage body to the inside (and is discharged from the top of the heat exchange chamber after preheating).

[0163] In the second mode, it is suitable for consumables with larger particle size, refer to Figure 5 , 7 -9, in this embodiment, the electric support rod controls the movement of the lifting platform and drives another driving wheel to engage with the driving rod. The number of meshing tooth structures on the driving wheel increases, but the number of meshing teeth in each group of meshing tooth structures decreases (refer to Fig. 9 ), therefore, when controlling the activity of the driving rod, the stroke of a single activity of the driving rod can be shortened, thereby avoiding contact between the linkage rod on the movable block and the vacuum block. Therefore, air can only be pumped through the airflow negative pressure chamber, thereby preheating the consumables in the storage body only through the outside of the storage body.

[0164] In order to avoid the melting of consumables in the storage body due to excessive temperature during the preheating process, a control structure is provided in the present embodiment. When the movable block moves, when the support rod of the control structure contacts the inner wall of the negative pressure chamber, the rack and the gear are driven to engage. Therefore, when the movable block moves, the gear can be driven to rotate, and the gear can be used to drive the linkage shaft to rotate so that the heat exchanger rotates around the storage body. When the heat exchanger moves to the spacing groove on the outer wall of the storage body, the heat exchanger is separated from the storage body, thereby stopping the preheating. When the heat exchanger contacts the storage body, the storage body is preheated. Therefore, this intermittent preheating method can not only achieve the purpose of preheating, but also avoid the consumables from melting in the storage body due to excessive temperature.

[0165] The first spring arranged on the control structure can drive the rack to separate from the gear, that is, when one end of the support rod moves to the notch position formed on the inner wall of the negative pressure chamber (the notch is recessed on the inner wall of the negative pressure chamber, and the notch and the inner wall of the negative pressure chamber form a driving surface), the rack is separated from the gear, and when one end of the support rod contacts the inner wall of the negative pressure chamber, the support rod moves toward the direction of the gear and makes the rack engage with the gear. Therefore, when the movable block moves, the gear can be driven to rotate. When the gear rotates, not only can the linkage shaft be controlled to drive the heat exchanger to rotate, but the anti-blocking rod can also be controlled to rotate in the discharge pipe to prevent the consumables from being blocked in the discharge pipe.

[0166] It should be noted that the notches in each negative pressure chamber of the present embodiment are staggered, so that when the movable block in the negative pressure chamber moves, only the rack on one movable block is engaged with the gear, thereby ensuring the smooth movement of the rack and gear, and also ensuring the smooth and stable operation of the overall negative pressure discharging mechanism.

[0167] A return spring 100a is provided in the negative pressure chamber to connect the inner wall of the negative pressure chamber and the movable block. Figure 6 For example, the return spring 100a in the upper negative pressure chamber is used to drive the movable block to move closer to the vacuum chamber, and the return spring 100a in the lower negative pressure chamber is used to drive the movable block to move away from the vacuum chamber. Therefore, the reciprocating motion of the movable block is completed with the cooperation of the return spring and the driving structure.

[0168] In other embodiments, in order to better preheat, a stirring plate may be provided on the linkage shaft. When the linkage shaft rotates, the stirring plate is utilized to drive the consumables in the storage chamber to move, so as to better preheat the consumables.

[0169] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A negative pressure discharging mechanism, characterized in that: The order of discharge includes: Storage module (21); Negative pressure module (22); A heating module (23) having a discharge end; The negative pressure module (22) at least comprises a material negative pressure chamber (22a) and an airflow negative pressure chamber (22b), and the material negative pressure chamber (22a) and the airflow negative pressure chamber (22b) can be controlled to form negative pressure in turn; When the material negative pressure chamber (22a) forms a negative pressure, the material in the material storage module (21) is sent into the material negative pressure chamber, and when the material negative pressure chamber is restored, the material is sent into the heating module; When the negative pressure chamber (22b) forms a negative pressure, outside air is introduced into the negative pressure chamber (22b) to recover the waste heat of the heating module (23), and when the negative pressure chamber (22b) is restored, the hot air is sent to the material storage module (21) to preheat the material; The negative pressure module (22) comprises: A negative pressure body (220) having at least two negative pressure chambers therein; At least two movable blocks (30) are controlled to move in each negative pressure chamber, and each negative pressure chamber is divided into the material negative pressure chamber (22a) and the airflow negative pressure chamber (22b); An air intake structure and an air exhaust structure are provided on the negative pressure body (220) and are capable of communicating with the airflow negative pressure chamber (22b), and are capable of controlling the unidirectional flow of gas; At least two driving rods (31), connected to each movable block (30), and one end of which passes through the negative pressure body (220); A driving structure, installed on one side of the negative pressure body (220) and capable of controlling the reciprocating motion of each driving rod (31); When the driving structure controls the driving rod (31) to move and expand the material negative pressure chamber (22a) or the airflow negative pressure chamber (22b), negative pressure is formed in the material negative pressure chamber (22a) or the airflow negative pressure chamber (22b); The exhaust structure comprises: An exhaust pipe (60) is provided on the negative pressure body (220), is communicated with the airflow negative pressure chamber (22b), and is provided with a one-way valve (55); A support body (61) is supported by the exhaust pipe (60) and is arranged in a recessed manner on a side away from the exhaust pipe (60); A movable body (62) cooperates with the supporting body (61) and is capable of rotating and moving on the supporting body (61); A connecting pipe (63) mounted on the movable body (62); Wherein, an air cavity (65) communicating with the exhaust pipe (60) and the connecting pipe (63) is formed between the support body (61) and the movable body (62); The material storage module (21) comprises: A material storage body (70) is mounted on the negative pressure body (220) and has a material storage cavity (71); A material discharge chamber, which is provided between the material storage body (70) and the negative pressure body (220), and is in communication with the material storage chamber (71) and the material negative pressure chamber (22a); A heat exchange body (72) is coaxially sleeved on the material storage body (70) and is capable of contacting the material storage body (70), and has a limit tube (73) that can be detachably connected to the connecting tube (63); Wherein, the heat exchange body (72) is provided with a heat exchange cavity (72a) which is in communication with the limiting tube (73); The negative pressure body (220) is provided with a rotating structure, wherein the rotating structure comprises: A rotating shaft (80) is rotatably disposed on the negative pressure body (220), and two ends thereof extend toward the discharge pipe (50) and the material storage chamber (71), respectively; An anti-blocking rod (81) is mounted on the rotating shaft (80) and is located in the discharge pipe (50); A linkage shaft (82) is detachably disposed on the rotating shaft (80) and is connected to the heat exchange body (72); The heat exchange body (72) is composed of a rotating body (720) connected to the linkage shaft (82) and an air inlet (721) provided on the inner wall of the rotating body (720) and capable of contacting the outer wall of the material storage body (70); The outer wall of the material storage body (70) is recessed and provided with a plurality of spacing grooves (70a) which are distributed at intervals and capable of separating the material storage body (70) from the air intake (721).

2. A negative pressure discharging mechanism according to claim 1, characterized in that: The driving structure comprises: A driving box (40) is installed on one side of the negative pressure body (220); The lifting platform (41) can be controlled by an electric support rod (42) to move up and down in the driving box (40); A transmission shaft (43) is rotatably mounted on the lifting platform (41) and can be driven to rotate by a motor (44); At least two driving wheels (45) are installed on the transmission shaft (43) at intervals; Wherein, the driving wheel (45) and the driving rod (31) are provided with meshing tooth structures (46) capable of meshing with each other.

3. A negative pressure discharging mechanism according to claim 1 or 2, characterized in that: The heating module (23) comprises: A material discharge pipe (50) is installed on the negative pressure body (220) and is in communication with the material negative pressure chamber (22a); A nozzle (51) is mounted on the discharge pipe (50); A heater (52) is installed on the discharge pipe (50) and is used to heat the discharge pipe (50); The air intake structure is composed of an air intake pipe (540, 541) provided on the negative pressure body (220) and led to the heater (52), and a one-way valve (55) provided on the air intake pipe.

4. A negative pressure discharging mechanism according to claim 1, characterized in that: The rotating shaft (80) is provided with a gear (90) located between the negative pressure chambers, and the movable block is provided with a control structure for driving the gear (90) to rotate, the control structure comprising: A control groove (91) is recessed and arranged on a side of the movable block (30) close to the gear (90); A penetrating cavity (92) penetrates the movable block (30) and is in communication with the control groove (91); A rack (93) is installed in the control groove (91) via a first spring (94); A support rod (95) connected to the rack (93) and extending through the through cavity (92) and in contact with the cavity wall of the negative pressure cavity; The wall of the negative pressure chamber is formed with a driving surface (96) for the end of the support rod (95) to move, and when the end of the support rod slides on the driving surface (96), the rack (93) and the gear (90) are meshed or disengaged.

5. A negative pressure discharging mechanism according to claim 4, characterized in that: An air extraction cavity (97) is also formed on the negative pressure body (220), an exhaust passage (98) in communication with the air extraction cavity (97) is formed in the negative pressure body (220), and a central heat exchange cavity (99) in communication with the exhaust passage (98) and penetrating the top is formed in the rotating shaft (80) and the linkage shaft (82); The pumping cavity (97) is provided with a pumping structure, the pumping structure comprising a pumping body (97a) and a second spring (97b), the pumping body (97a) being connected to the pumping cavity (97) via the second spring (97b), and a linkage rod (97c) penetrating into the pumping cavity (97) is provided on the movable block (30), and a matching groove (97d) for the linkage rod (97c) to move is provided on a side of the pumping body (97a) close to the movable block (30); The negative pressure body (220) is also provided with an air suction structure connected to the air suction cavity.

6. A 3D printer, comprising a frame (10, 11), an X-axis drive mechanism (13), a Y-axis drive mechanism (14), a Z-axis drive mechanism (15) and a heated bed (12), characterized in that: It also includes a negative pressure discharge mechanism (2) as claimed in any one of claims 4 to 5; The negative pressure discharge mechanism (2) is installed on the X-axis drive mechanism (13) or the Y-axis drive mechanism (14) or the Z-axis drive mechanism (15).

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