Vacuum mixer for ultra-high performance concrete

Abstract

The present invention relates to the technical field of concrete mixers. A vacuum mixer for ultra-high performance concrete includes a mixing cylinder body, a mixing assembly, a vacuum pumping assembly, and a feeding assembly. A cover body is provided at the top of the mixing cylinder body; the mixing assembly is arranged inside the mixing cylinder body and is used for mixing and stirring the mixture. A sealing unit is arranged between the mixing assembly and the mixing cylinder body; the vacuum pumping assembly is connected to the mixing cylinder body and is used for pumping vacuum inside the mixing cylinder body; the feeding assembly is connected to the mixing cylinder body through a feeding pipeline, and a sealing valve is arranged on the feeding pipeline. The structure of the present application is reasonably designed, which can ensure the constancy of the vacuum degree inside the mixing cylinder body, improve the quality of the mixture after stirring, optimize the structure of the product, and improve the service life and the convenience of use.

Description

Technical Field

[0001] The present invention relates to the technical field of concrete mixers, and particularly to a vacuum mixer for ultra-high performance concrete. Background Art

[0002] Ultra-High Performance Concrete (UHPC for short) is a new development in modern concrete technology, which is jointly promoted by good particle packing, appropriate mixing procedures, scientific curing systems, and appropriate amounts of binders and admixtures. UHPC has attracted increasing attention due to its excellent performance and has a wider range of applications. Using UHPC as the outer protective panel of a building can not only reduce the impact damage caused by external forces such as aircraft to important facilities such as nuclear power plants, high-rise buildings, and power plants, but also achieve an ideal aesthetic effect; its high fluidity and self-compacting performance make it more suitable for structures with complex formworks and high reinforcement ratios; its excellent durability is also an ideal choice for buildings serving in harsh environments. However, UHPC removes coarse aggregates to improve homogeneity, needs to add highly reactive micro-powders such as silica fume to obtain a dense microstructure, must use a lower water-binder ratio to increase strength, and needs to add more admixtures to meet workability requirements, resulting in much higher dosages of binders and admixtures than traditional concrete, making the mixture more viscous and the air introduced during the mixing process more difficult to eliminate. Generally speaking, the introduced air has an important impact on the workability of fresh concrete and the quality of hardened concrete. The accumulation of air bubbles under fibers or steel bars will reduce the bond strength between fibers / steel bars and the surrounding cement matrix, and a higher air content is also the main reason why it is difficult for UHPC prepared by conventional methods to exceed 200 MPa in compressive strength. Research shows that taking measures to reduce the atmospheric pressure in the mixture during the mixing process can effectively eliminate the bubble content and reduce the bubble pore size, thereby improving the performance of hardened concrete. For this reason, researchers have developed a vacuum mixer that can reduce the bubble content in the concrete mixture. For example, Chinese Patent (CN201620604914.3) discloses a concrete vacuum mixer. The vacuum mixer described in this application has made a breakthrough contribution to improving the compactness, strength, and durability of concrete. However, this application only targets a forced concrete vacuum mixer, whose structural feature is that the motor is placed outside the mixing drum, and the rotating shaft connected to the motor has to pass through the mixing drum, and it is very difficult to ensure the airtightness and vacuum degree of the mixing drum at the connection between the rotating shaft and the mixing drum. At the same time, the feeding and mixing procedures of this application will also affect the concrete performance and are more unsuitable for mixing UHPC mixtures. To solve the problems existing in this application, another Chinese Patent (CN201721108634.4) attempts to address them. What this application proposes is a tapered reverse-discharge concrete vacuum mixer, whose feature is that the motor drives the mixing drum to rotate during the mixing process. However, due to the rotation of the mixing drum, vacuum pumping must be completed before mixing, but the vacuum degree in the mixing drum will be lost during the water addition and mixing processes. Since continuous vacuum pumping cannot be carried out, the effect of eliminating air bubbles in the mixture is limited. Especially the lack of the puncturing effect of forced blades on air bubbles and the relatively low rotation speed of the mixing drum determine that this mixer is not suitable for mixing more viscous UHPC mixtures, especially those containing fibers.Therefore, it is necessary to develop a new vacuum mixer with reasonable structure, environmental protection and high efficiency, and more suitable for the preparation of ultra-high performance concrete (UHPC) mixture. Summary of the invention

[0003] The purpose of the present invention is to provide a vacuum mixer for ultra-high performance concrete in view of the above-mentioned problems and shortcomings, which has a reasonable structural design, can ensure a constant vacuum degree in the mixing drum, improve the quality of the mixed material after mixing, optimize the structure of the product, and increase the service life and convenience of use.

[0004] To achieve the above purpose, the technical solution adopted is:

[0005] A vacuum mixer for ultra-high performance concrete, comprising:

[0006] A mixing cylinder, wherein a cover is provided on the top of the mixing cylinder;

[0007] A stirring assembly is disposed in the stirring cylinder and is used for stirring and mixing the mixing material. A sealing unit is disposed between the stirring assembly and the stirring cylinder;

[0008] A vacuuming assembly connected to the mixing drum and used to vacuum the mixing drum; and

[0009] A feeding assembly is connected to the mixing drum through a feeding pipeline, and a sealing valve is provided on the feeding pipeline.

[0010] According to the vacuum mixer for ultra-high performance concrete of the present invention, preferably, the mixing assembly comprises:

[0011] A stirring shaft, which is arranged on the cover body through a bearing;

[0012] A stirring motor is disposed on the cover body and is drivingly connected to the stirring shaft; and

[0013] A stirring blade is arranged on the stirring shaft.

[0014] According to the vacuum mixer for ultra-high performance concrete of the present invention, preferably, the stirring blade comprises a spiral blade, the spiral blade is arranged on the stirring shaft, and a plurality of groups of supporting rods are further arranged between the spiral blade and the stirring shaft;

[0015] The sealing unit is a sealing box arranged on the cover body outside the stirring motor, or / and the sealing unit is an airtight bearing arranged between the stirring shaft and the cover body.

[0016] According to the vacuum mixer for ultra-high performance concrete of the present invention, preferably, the vacuum pumping assembly comprises:

[0017] A vacuum extraction pipe, which is fixedly arranged on the stirring cylinder body, and a vacuum valve is arranged on the vacuum extraction pipe; and

[0018] A vacuum pump, which is arranged at the outer end of the vacuum extraction pipe.

[0019] According to the vacuum mixer for ultra-high performance concrete of the present invention, preferably, a dust suction unit is connected to the vacuum extraction pipe through a reversing valve, and an air flow control valve is arranged on the branch pipeline between the vacuum extraction pipe and the dust suction unit; a vacuum gauge and a vacuum valve are also connected to the vacuum extraction pipe through a branch pipeline, and an exhaust silencing valve is arranged at the air outlet end of the vacuum pump.

[0020] According to the vacuum mixer for ultra-high performance concrete of the present invention, preferably, the feeding assembly includes a solid material supply unit and a liquid material supply unit, the solid material supply unit includes a solid material conveying pipeline, a solid material sealing valve arranged on the solid material conveying pipeline, and a solid material feeding device connected to the solid material conveying pipeline;

[0021] The liquid material supply unit includes a liquid material conveying pipeline, a liquid material sealing valve arranged on the liquid material conveying pipeline, and a liquid material feeding device connected to the liquid material conveying pipeline.

[0022] According to the vacuum mixer for ultra-high performance concrete of the present invention, preferably, the solid material feeding device includes a silo, a conveyor, a metering device, a solid material storage tank and a solid material control valve, and a plurality of the silos are communicated with the solid material storage tank through corresponding conveyors and metering devices; a liquid material spray head is arranged at the inner end of the liquid material conveying pipeline, and the liquid material feeding device includes a raw material tank, a flow pump, and a liquid material storage tank, and a plurality of the raw material tanks are communicated with the liquid material storage tank through corresponding flow pumps.

[0023] According to the vacuum mixer for ultra-high performance concrete of the present invention, preferably, a discharge port and a discharge assembly are arranged at the bottom of the stirring cylinder body, and the discharge assembly includes:

[0024] A discharge door, which is hinged to the stirring cylinder body;

[0025] A limiting platform, which is arranged at the bottom of the stirring cylinder body and corresponds to the movable end of the discharge door;

[0026] An anti-detachment locking pin, which is slidably arranged on the limiting platform, and a first compression spring is arranged between the anti-detachment locking pin and the limiting platform, the first compression spring drives the anti-detachment locking pin to keep in an extended state, and when the discharge door is in a closed state, the anti-detachment locking pin is limited and supported at the lower part of the discharge door; and

[0027] An elastic opening unit, which is arranged at the hinged end of the discharge door, and the elastic opening unit is a torsion spring or a second compression spring;

[0028] The discharge port is conical, a sealing cone is arranged on the upper part of the discharge door, an annular sealing groove is arranged on the sealing cone, and a sealing filler or a sealing ring is arranged in the annular sealing groove.

[0029] According to the vacuum mixer for ultra-high performance concrete of the present invention, preferably, the cover body and the mixing drum body are an integrated structure, and a base is provided on the mixing drum body or the cover body.

[0030] According to the vacuum mixer for ultra-high performance concrete of the present invention, preferably, the cover body and the mixing drum are split structures, a hoop is provided at the bottom of the cover body, an assembly sink is provided at the bottom of the hoop, a first thread segment is provided on one side of the assembly sink, a sealing belt is embedded at the bottom of the assembly sink, a second thread segment matching the first thread segment is provided on the upper part of the mixing drum, and the top of the mixing drum is sealed with the sealing belt; a base is provided on the cover body, and a base and / or a handle is provided on the mixing drum.

[0031] The beneficial effects achieved by adopting the above technical solution are:

[0032] (1) The structural design of the present application is reasonable, which can ensure a constant vacuum degree in the mixing drum, improve the quality of the mixed material after mixing, optimize the product structure, and improve the service life and convenience of use. By setting an airtight bearing, the problem of loss of vacuum degree in the mixing drum due to bearing leakage in the prior art can be overcome, and a sealing box can also be set to further seal the structure.

[0033] (2) The integrated connection between the vacuum pump and the mixing drum of the present application can overcome the loss of vacuum during the mixing process caused by the split connection, thereby achieving continuous vacuuming and maintaining a constant vacuum level in the mixing drum. The present application uses a digital vacuum meter (vacuum gauge) to display and transmit the vacuum level in the mixing drum during the mixing process in real time, thereby controlling the vacuum level and keeping it constant.

[0034] (3) The present application can remove dust in the mixing drum before vacuuming by setting a dust suction unit, thereby avoiding the dust being sucked into the vacuum pump and causing damage to the vacuum pump, thereby achieving a better vacuuming effect; the setting of the exhaust silencer valve on the vacuum pump can eliminate the noise generated during vacuuming as much as possible, thereby achieving a better environmental effect.

[0035] (4) The present application can accurately control the setting of the solid material supply unit and the liquid material supply unit of the material quantity and water supply, which can ensure that the mix ratio of ultra-high performance concrete (UHPC) is consistent with the designed mix ratio and obtain high-quality mixture; the liquid material supply unit with control of water pressure and flow rate is not only convenient for water supply and mixing, but also convenient for flushing the mixing drum.

[0036] (5) The different structural designs of the mixing cylinder and the cover in this application enable applications in different scenarios. The spherical crown-shaped structure at the bottom of the mixing cylinder facilitates the smooth outflow of the slurry and is also conducive to thoroughly rinsing the mixing cylinder. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings of the embodiments of the present invention will be briefly introduced below. Among them, the accompanying drawings are only used to show some embodiments of the present invention, rather than limiting all embodiments of the present invention thereto.

[0038] Figure 1 is one of the schematic structural diagrams of the vacuum mixer for ultra-high performance concrete according to the embodiment of the present invention;

[0039] Figure 2 is Figure 1 the enlarged structural schematic diagram of part A in

[0040] Figure 3 is Figure 1 the cross-sectional view taken along the line B-B in

[0041] Figure 4 is another schematic structural diagram of the vacuum mixer for ultra-high performance concrete according to the embodiment of the present invention;

[0042] Figure 5 is the third schematic structural diagram of the vacuum mixer for ultra-high performance concrete according to the embodiment of the present invention.

[0043] In the figures: 1 - solid material supply equipment; 2 - airtight material valve; 3 - mixing motor; 4 - liquid material supply equipment; 5 - airtight bearing; 6 - cover; 7 - mixing shaft; 8 - spray head; 9 - mixing paddle; 10 - support rod; 11 - mixing cylinder; 12 - discharge door; 13 - sealing ring; 14 - rotating shaft; 15 - spring-opening unit; 16 - limiting platform; 17 - anti-disengagement locking pin; 18 - first compression spring; 19 - air valve; 20 - reversing valve; 21 - air flow control valve; 22 - vacuum gauge; 23 - vacuum valve; 24 - dust collection unit; 25 - air collection hood; 26 - vacuum pump; 27 - exhaust silencer valve; 28 - base; 29 - controller; 30 - microcomputer; 31 - hoop; 32 - mixing cylinder sealing strip; 33 - threaded connection structure; 34 - fixed lock; 35 - handle; 36 - base, 37 - extraction vacuum tube, 38 - limiting pin. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0044] In the following, the exemplary solutions of the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings of the specific embodiments of the present invention. Unless otherwise defined, the technical terms or scientific terms used in the present invention should have the ordinary meaning understood by those of ordinary skill in the art.

[0045] In the description of the present invention, it should be understood that the expressions "first" and "second" are used to describe the various elements of the present invention, and do not represent any limitation of order, quantity or importance, but are only used to distinguish one component from another component.

[0046] It should be noted that when there is an expression of "connected", "coupled" or "linked" between one element and another element, it may mean that they are directly connected, coupled or linked, but it should be understood that there may be intermediate elements between the two; that is, it covers the positional relationship of direct connection and indirect connection.

[0047] It should be noted that the use of similar words such as "a" or "an" does not necessarily indicate a limitation of quantity. Similar words such as "comprising" or "including" mean that the elements or objects appearing before this word cover the elements or objects listed after this word and their equivalents, without excluding other elements or objects.

[0048] It should be noted that terms indicating orientation or positional relationship such as "upper", "lower", "left", "right", etc. are only used to represent relative positional relationships, which are for the convenience of describing the present invention, rather than the device or element must have a specific orientation, be constructed and operated in a specific orientation; when the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0049] See Figures 1 - 5 , a vacuum mixer for ultra-high performance concrete in the present application, includes a mixing cylinder body 11, a mixing component, a vacuum pumping component and a feeding component. A cover body 6 is arranged at the top of the mixing cylinder body; the mixing component is arranged in the mixing cylinder body and is used for mixing and stirring the mixture. A sealing unit is arranged between the mixing component and the mixing cylinder body; the vacuum pumping component is connected to the mixing cylinder body and is used for pumping vacuum in the mixing cylinder body; the feeding component is connected to the mixing cylinder body through a feeding pipeline, and a sealing valve is arranged on the feeding pipeline.

[0050] The mixing component in this embodiment includes a mixing shaft, a mixing motor and mixing blades. The mixing shaft is arranged on the cover body through a bearing; the mixing motor is arranged on the cover body, and the mixing motor is in transmission connection with the mixing shaft; the mixing blades are arranged on the mixing shaft. The mixing motor in the present application is preferably a servo motor, and a stepping motor can also be used. Among them, the mixing blade 9 includes a spiral blade. The spiral blade is arranged on the mixing shaft 7, and multiple groups of support rods 10 are also arranged between the spiral blade and the mixing shaft; the sealing unit is a sealing box arranged on the cover body outside the mixing motor, and / or the sealing unit is an airtight bearing 5 arranged between the mixing shaft and the cover body.

[0051] Specifically, the structure and function of the stirring assembly are described in detail: the stirring assembly includes a power device (i.e., a stirring motor 3), an airtight bearing 5, a stirring shaft 7, stirring blades 9, and a support rod 10. The power device is fixedly connected to the upper part of the cover body 6 and is located just at the top center of the stirring cylinder. The stirring main shaft connected as a whole with the power device passes through the airtight bearing and extends into the stirring cylinder and is located on the central axis of the stirring cylinder. The strip-shaped stirring blades spirally retract from top to bottom with the stirring main shaft as the center to the end of the stirring main shaft above the bottom center of the stirring cylinder. The stirring blades are fixedly connected to the stirring main shaft through support rods arranged horizontally in a cross shape, but each support rod is not on the same plane in the vertical direction, but is arranged spirally around the main shaft together with the blades, such as Figure 3 The strip blade has a certain inclination angle with the horizontal plane, and the outer edge contacts the inner wall of the mixing drum. The power device is mainly composed of a servo motor, and the speed and direction can be regulated by means of a control system. By reasonably designing and regulating the slow, medium and high speed mixing processes, different mixtures can obtain ideal mixing effects. Timely switching of the blade direction can improve the mixing and unloading efficiency.

[0052] The vacuum pump assembly in this embodiment includes a vacuum pump tube and a vacuum pump 26. The vacuum pump tube 37 is fixedly arranged on the cover body 6, and a vacuum valve 23 is arranged on the vacuum pump tube; the vacuum pump 26 is arranged at the outer end of the vacuum pump tube.

[0053] The vacuum pipe is connected to a dust collection unit via a reversing valve, and an airflow control valve 21 is provided on a branch pipeline between the vacuum pipe and the dust collection unit; the vacuum pipe is also connected to a vacuum meter 22 and a vacuum valve 23 via a branch pipeline, and an exhaust silencer valve 27 is provided at the outlet end of the vacuum pump.

[0054] The structure of the vacuum extraction assembly and the functions of its various components are described in detail as follows: It specifically includes an air valve 19, a reversing valve 20, an air flow control valve 21, a vacuum gauge 22, a vacuum valve 23, a dust collection unit 24, an air collection hood 25, a vacuum pump 26, an exhaust silencer valve 27, etc. The air collection hood arranged inside the mixing drum is connected to the air valve and the reversing valve respectively through a pipe tee. The air valve is a digitally controlled air valve. When closed, it can make the inside of the mixing drum form a vacuum state through the vacuum pump, facilitating the mixing of ultra-high performance concrete mixtures; when opened, it makes the inside of the mixing drum return to normal pressure, facilitating the discharged ultra-high performance concrete mixture to flow out from the discharge port. One path of the reversing valve is connected to the dust collection unit through the air flow control valve, and the other path is connected to the vacuum pump through the vacuum valve. A vacuum gauge with vacuum pressure sensing and numerical display functions is connected between the vacuum valve and the reversing valve, and a valve with exhaust silencing function is arranged at the exhaust port of the vacuum pump. When powder materials are put into the mixer, the air valve is closed, the reversing valve connects the pipeline to the dust collection unit, and part of the dust flows to the dust collection unit along with the air flow. Before vacuum extraction after the powder material is put in, the spray head starts the spraying function to eliminate the influence of suspended fine dust on the vacuum pump, but the water consumption needs to be strictly calculated within the mix proportion of the ultra-high performance concrete.

[0055] The feeding assembly in this embodiment includes a solid material supply unit and a liquid material supply unit. The solid material supply unit includes a solid material conveying pipeline, a solid material sealing valve arranged on the solid material conveying pipeline, and a solid material feeding device connected to the solid material conveying pipeline; the liquid material supply unit includes a liquid material conveying pipeline, a liquid material sealing valve arranged on the liquid material conveying pipeline, and a liquid material feeding device connected to the liquid material conveying pipeline.

[0056] The solid material feeding device includes a silo, a conveyor, a metering device, a solid material storage tank, and a solid material control valve. Multiple silos are communicated with the solid material storage tank through corresponding conveyors and metering devices; a liquid material spray head is arranged at the inner end of the liquid material conveying pipeline. The liquid material feeding device includes a raw material tank, a flow pump, and a liquid material storage tank. Multiple raw material tanks are communicated with the liquid material storage tank through corresponding flow pumps.

[0057] Regarding the structure and functions of the feeding assembly, the following detailed description is provided: The solid material supply unit mainly consists of a solid material feeding device 1, an airtight material valve 2, a material pipe, etc. The solid material feeding device is connected to the airtight material valve at the lower part and then extends into the mixing drum through the material pipe. The solid material feeding device is connected to silos storing different types of solid materials (granular materials and powder materials), and can supply materials after premixing according to different particle gradations of ultra-high performance concrete or supply materials separately in sequence. With the aid of the metering sensors configured in the solid material feeding device, the airtight material valve, and the program set by the control system, the supply amount of each solid material can be accurately controlled to meet the material quantity requirements of the mix proportion design. The mixed materials can be stored in the solid material storage tank and then the feeding is controlled through the solid material control valve.

[0058] The liquid material supply unit is mainly composed of liquid material supply equipment 4, liquid delivery pipeline, control valve and nozzle 8. The liquid material supply equipment can be composed of a water tank, a water pump (both of which can be replaced by tap water pipelines), a raw material tank for storing various admixtures, a liquid material storage tank, a pressure regulating valve, a solenoid valve, a flow meter, etc. The various liquid materials can be pre-mixed according to the requirements of the mix ratio through the control system and then sent to the nozzle for use through the oil pipeline. Different liquid materials can also be transported to the mixing drum in turn to participate in the mixing of the mixture. The precise control of the supply amount of various liquid materials provides a guarantee for mixing ultra-high performance concrete mixtures that meet the design requirements. The nozzle is an intelligent control nozzle with functional modes such as splashing, spraying and spraying to achieve different uses. When mixing the mixture, the nozzle sprays in a spraying manner, which not only makes the solid material contact with water more uniformly and fully during mixing, thereby improving the mixing quality and efficiency of the mixture, but also, after unloading, flushes the mixing cylinder with tap water in a splashing manner, thereby improving the efficiency of flushing the mixing cylinder. Different raw materials can also be mixed and stored in the liquid material discharge pipe, and then the liquid material sealing valve can be used to control the feed.

[0059] The bottom of the mixing drum in this embodiment is provided with a discharge port and a discharge assembly, and the discharge assembly includes a discharge door 12, a limit platform 16, an anti-dropping lock pin 17 and a spring-opening unit. The discharge door 12 is hinged to the mixing drum 11; the limit platform 16 is provided at the bottom of the mixing drum, and the limit platform corresponds to the movable end of the discharge door; the anti-dropping lock pin 17 is slidably provided on the limit platform, and a first compression spring 18 is provided between the anti-dropping lock pin and the limit platform, and the first compression spring 18 drives the anti-dropping lock pin to maintain an extended state, and when the discharge door is closed, the anti-dropping lock pin is limitedly supported at the lower part of the discharge door; the spring-opening unit is provided at the hinged end of the discharge door, and the spring-opening unit 15 is a torsion spring or a second compression spring. The discharge port is conical, and a sealing cone is provided at the upper part of the discharge door, and an annular sealing groove is provided on the sealing cone, and a sealing filler or a sealing ring 13 is provided in the annular sealing groove.

[0060] The structure and function of the discharging assembly are described in detail as follows: Figure 2, the discharge door is movably connected to the mixing cylinder through a rotating shaft 14 and can be smoothly pressed into the discharge port of the mixing cylinder. To form a tight fit, the vertical directions of the discharge port and the discharge door are designed as conical or square conical structures. A groove is provided in the circumferential direction where the discharge door contacts the discharge port, and a sealing ring 13 is provided in the groove to ensure sufficient airtightness. To ensure that the discharge door has sufficient opening and can be opened at high speed during unloading, an elastic opening unit 15 is provided between the discharge port and the discharge door around the rotating shaft, and the elastic opening unit is an elastic element. To prevent the discharge door from being popped open or falling during mixing, an anti-detachment locking pin 17 is provided at the outer edge of the discharge port on the side opposite to the rotating shaft. A limit pin 38 is provided at the corresponding position of the movable end of the discharge door. To facilitate the smooth pressing of the discharge door into the discharge port, the surfaces of the limit pin and the anti-detachment locking pin that contact are both designed as arc surfaces. The anti-detachment locking pin can move left and right through a first compression spring 18 and an external force in the guiding slideway. When the discharge door is pressed into the discharge port, the anti-detachment locking pin locks the discharge door under the drive of the first compression spring, forming a sealed mixing chamber in the mixing cylinder.

[0061] For the fixing method of the cover body and the mixing cylinder, this application provides different structures, which can adopt an integral structure design or a split structure design. When adopting an integral structure design, a base 28 can be provided on the mixing cylinder or the cover body; when adopting a split structure design, a hoop 31 is provided at the bottom of the cover body, an assembly sink is provided at the bottom of the hoop, a first threaded section is provided on one side of the assembly sink, a mixing cylinder sealing belt 32 is embedded at the bottom of the assembly sink, a second threaded section matching the first threaded section is provided on the upper part of the mixing cylinder, and the top of the mixing cylinder is sealed in contact with the sealing belt; a base 28 is provided on the cover body, and a base 36 or a handle 35 is provided on the mixing cylinder.

[0062] For the above-mentioned split body, the feeding assembly of this application can be not provided, so that the cover body and the mixing cylinder can be directly separated during feeding or discharging.

[0063] The following detailed description is made for the above different forms of structures:

[0064] See Figure 4 , this embodiment is basically the same as Figure 1 , the difference is that: the mixing cylinder and the cover body adopt a split design. The mixing cylinder and the cover body are connected through a threaded connection structure 33. To avoid the pollution of the contact part by the slurry, a hoop is provided at the bottom of the cover body, and an assembly sink corresponding to the mixing cylinder is provided on the hoop. To ensure the vacuum degree, an annular mixing cylinder sealing belt 32 is provided at the bottom of the assembly sink. To facilitate the disassembly and assembly of the mixing cylinder, 1-2 pairs of handles can be provided on the outer side wall of the mixing cylinder according to the capacity size. To avoid the mixing cylinder falling off during mixing, a fixed lock 34 is provided on one side of the hoop. At the same time, the rotation direction of the propeller blade can be set to be the same as the tightening direction of the mixing cylinder during mixing.

[0065] See Figure 5 。It is basically the same as the real Figure 4 , except that: to meet the need of mixing ultra-high performance concrete mixtures with a smaller capacity, there is no discharge door at the bottom of the mixing cylinder, but a base 36 is provided to facilitate the stable placement of the mixing cylinder.

[0066] The setting of the control system of this application can ensure the accurate implementation of feeding, water supply, vacuum pumping, etc., and ensure that ultra-high performance concrete (UHPC) mixtures that meet the design requirements are mixed.

[0067] Specifically, the control system includes a controller 29 and a microcomputer 30, as well as various sensors respectively connected to the mixing component, solid material supply unit, liquid material supply unit, and vacuum pumping component. Each sensor transmits the analog signals such as the motor speed, material flow rate, and vacuum degree collected to the controller through cables. The controller records and saves the data after digital-to-analog signal conversion, and displays it in real time through the display of the microcomputer. At the same time, the control system precisely regulates the actions of functional components such as the motor speed, material flow rate, and vacuum degree according to the feedback signals.

[0068] The method steps of using the vacuum mixer for ultra-high performance concrete (UHPC) of the present invention are as follows:

[0069] (1) Prepare sufficient raw materials according to the mix ratio requirements and place them in the solid material supply unit and the liquid material supply unit respectively.

[0070] (2) Close the discharge door and air valve of the mixing cylinder, open the pipeline connecting the dust collection unit by the reversing valve, and open the air flow control valve.

[0071] (3) Control the solid material supply unit to feed solid raw materials according to the characteristics of the prepared ultra-high performance concrete.

[0072] (4) Turn on the dust collection unit for dust removal.

[0073] (5) The spray head of the liquid material supply unit starts the tap water spray mode to eliminate extremely fine floating dust particles.

[0074] (6) The reversing valve connects to the vacuum pump for vacuum pumping. After reaching the design requirements, close the vacuum valve.

[0075] (7) Start the mixing component, add liquid raw materials by spraying while mixing, and perform slow, medium, and high-speed mixing in sequence according to the set program. During this period, if the vacuum degree is insufficient, the vacuum pump can be continuously turned on to maintain a constant vacuum degree.

[0076] (8) After mixing is completed, turn off the vacuum pumping component and open the air valve.

[0077] (9) Open the discharge door for discharging, and the stirring assembly can be started to reverse the blades to assist in discharging.

[0078] (10) After discharging is completed, open the nozzle to rinse the stirring cylinder until it is clean.

[0079] The above operation steps can be automatically completed by a microcomputer controlled by a designed program.

[0080] For other embodiments, changing the specific specifications, dimensions, forms, etc. of the structures such as the cover body, stirring assembly, solid material supply unit, liquid material supply unit, vacuum pumping assembly, and control system of a vacuum mixer for ultra-high performance concrete of the present invention, such as setting the base directly below the stirring cylinder, or adding a transparent glass observation port on the wall of the stirring cylinder, or making the stirring cylinder from a specific material such as transparent tempered glass, are all common variations of the present invention and will not be elaborated one by one here.

[0081] The preferred embodiments for implementing the present invention have been described in detail above. However, it should be understood that the functions of these embodiments are only for illustration and not for limiting the scope, application, or construction of the present invention in any way. The protection scope of the present invention is defined by the appended claims and their equivalent means. Those of ordinary skill in the art can make many changes to the foregoing embodiments under the teaching of the present invention, and these changes all fall within the protection scope of the present invention.

Claims

1. A vacuum mixer for ultra-high performance concrete, characterized in that, include: A mixing cylinder, wherein a cover is provided on the top of the mixing cylinder; A stirring assembly is disposed in the stirring cylinder and is used for stirring and mixing the mixing material. A sealing unit is disposed between the stirring assembly and the stirring cylinder; A vacuum pumping assembly connected to the mixing cylinder and used to vacuum the mixing cylinder; as well as A feeding assembly, which is connected to the mixing drum through a feeding pipeline, and a sealing valve is provided on the feeding pipeline; The bottom of the mixing drum is provided with a discharge port and a discharge assembly, and the discharge assembly comprises: A discharge door, the discharge door being hinged to the mixing drum; A limiting platform, which is arranged at the bottom of the mixing drum, and the limiting platform corresponds to the movable end of the discharge door; An anti-dropout lock pin is slidably arranged on the limit platform, and a first compression spring is arranged between the anti-dropout lock pin and the limit platform, the first compression spring drives the anti-dropout lock pin to maintain an extended state, and when the discharge door is closed, the anti-dropout lock pin is limitedly supported at the lower part of the discharge door; and A spring-opening unit, which is arranged at the hinged end of the discharge door, and the spring-opening unit is a torsion spring or a second compression spring; The discharge port is conical, a sealing cone is provided on the upper part of the discharge door, an annular sealing groove is provided on the sealing cone, and a sealing filler or a sealing ring is provided in the annular sealing groove; The stirring blade comprises a spiral blade, the spiral blade is arranged on the stirring shaft, and a plurality of support rods are arranged between the spiral blade and the stirring shaft; The sealing unit is an airtight bearing disposed between the stirring shaft and the cover body, and the upper and lower ends of the airtight bearing correspond to the upper and lower surfaces of the cover body respectively; The method for using the ultra-high performance concrete vacuum mixer is as follows: (1) Prepare the raw materials according to the mix ratio requirements and place them in the solid material supply unit and the liquid material supply unit respectively; (2) Close the discharge door and air valve of the mixing drum, open the pipeline connected to the dust collection unit with the reversing valve, and open the air flow control valve; (3) The solid material supply unit puts in solid raw materials; (4) Turn on the dust collection unit to remove dust; (5) The nozzle of the liquid material supply unit starts the tap water spray mode to eliminate floating dust particles; (6) The reversing valve is connected to the vacuum pump to evacuate the air, and the vacuum valve is closed after the design requirements are met; (7) Turn on the stirring component and add liquid raw materials by spraying while stirring. If the vacuum degree is insufficient during this period, continue to turn on the vacuum pump to maintain a constant vacuum degree; (8) After stirring is completed, close the vacuum assembly and open the air valve; (9) Open the discharge door to unload the material, and turn on the stirring assembly to reverse the paddles to assist in unloading; (10) After unloading, open the nozzle to rinse the mixing cylinder until it is clean.

2. The vacuum mixer for ultra-high performance concrete according to claim 1, characterized in that, The stirring assembly comprises: A stirring shaft, which is arranged on the cover body through a bearing; A stirring motor is disposed on the cover body and is drivingly connected to the stirring shaft; and A stirring blade is arranged on the stirring shaft.

3. The vacuum mixer for ultra-high performance concrete according to claim 1, characterized in that, The vacuum assembly includes: A vacuum pumping tube, which is fixedly mounted on the mixing drum, and a vacuum valve is mounted on the vacuum pumping tube; and A vacuum pump is arranged at the outer end of the vacuum tube.

4. The vacuum mixer for ultra-high performance concrete according to claim 3, characterized in that, The evacuation pipe is connected to a dust suction unit through a reversing valve, and an air flow control valve is provided on the branch pipeline between the evacuation pipe and the dust suction unit; a vacuum gauge and a vacuum valve are also connected to the evacuation pipe through a branch pipeline, and an exhaust silencer valve is provided at the air outlet end of the vacuum pump.

5. The vacuum mixer for ultra-high performance concrete according to claim 1, characterized in that, The feeding assembly includes a solid material supply unit and a liquid material supply unit. The solid material supply unit includes a solid material conveying pipeline, a solid material sealing valve provided on the solid material conveying pipeline, and a solid material feeding device connected to the solid material conveying pipeline. The liquid material supply unit includes a liquid material conveying pipeline, a liquid material sealing valve provided on the liquid material conveying pipeline, and a liquid material feeding device connected to the liquid material conveying pipeline.

6. The vacuum mixer for ultra-high performance concrete according to claim 5, characterized in that, The solid material feeding device includes a silo, a conveyor, a metering device, a solid material storage tank, and a solid material control valve. A plurality of the silos communicate with the solid material storage tank through corresponding conveyors and metering devices; a liquid material spray head is provided at the inner end of the liquid material conveying pipeline. The liquid material feeding device includes a raw material tank, a flow pump, and a liquid material storage tank. A plurality of the raw material tanks communicate with the liquid material storage tank through corresponding flow pumps.

7. The vacuum mixer for ultra-high performance concrete according to claim 1, characterized in that, The cover body and the stirring cylinder body are of an integral structure, and a base is provided on the stirring cylinder body or the cover body.

8. The vacuum mixer for ultra-high performance concrete according to claim 1, characterized in that, The cover body and the stirring cylinder body are of a split structure. A hoop is provided at the bottom of the cover body, and an assembly sinking groove is provided at the bottom of the hoop. A first threaded section is provided on one side of the assembly sinking groove, and a sealing strip is embedded at the bottom of the assembly sinking groove. A second threaded section matching the first threaded section is provided on the upper part of the stirring cylinder body, and the top of the stirring cylinder body is sealed in contact with the sealing strip; a base is provided on the cover body, and a base or / and a handle are provided on the stirring cylinder body.

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