Concrete mixing device with movable blades

Abstract

The invention relates to the technical field of building construction equipment, in particular to a concrete mixing device with movable blades, which comprises a mixing drum, a mixing shaft, a vibrating screen component and an adjusting mixing component, the mixing shaft is arranged in the mixing drum, and the adjusting mixing component is mounted on the mixing shaft through a hinge structure. The angle and the length of the blade can be adjusted by adjusting the stirring assembly; the vibrating screen component is arranged at the top of the stirring barrel and can pretreat raw materials and remove caked impurities; by adjusting the stirring assembly, stirring dead angles can be eliminated, the concrete stirring uniformity is improved, material segregation is reduced, and the stirring efficiency is improved.

Description

Technical Field

[0001] This invention relates to the field of construction equipment technology, specifically to a concrete mixing device with movable blades. Background Technology

[0002] Concrete mixing is a core process in the construction industry. It refers to the process of using specialized equipment to forcibly mix, shear, and tumble raw materials such as cement, sand, gravel, water, and admixtures according to a preset ratio, so as to form a homogeneous and stable concrete mixture. The quality of concrete mixing directly determines the key properties of concrete, such as compressive strength and durability, and thus affects the safety and service life of building structures. Therefore, as a key piece of equipment for this process, the performance of concrete mixing equipment is of decisive significance to the quality of construction projects.

[0003] Most existing concrete mixing devices use fixed-installation blades, meaning the blades are rigidly connected to the mixing shaft, and the angle and length of the blades cannot be adjusted. This fixed-blade structure has the following drawbacks: First, the fixed angle and length of the blades result in a single mixing trajectory, failing to cover the corner areas between the mixing drum and the mixing shaft, the vicinity of the drum wall, and the shaft core area. This easily creates mixing blind spots, leading to incomplete mixing and poor uniformity of the concrete. Second, the fixed mixing trajectory of the blades causes the material to only form unidirectional circumferential flow or simple axial flow within the mixing drum, lacking complex convection and shearing effects, which affects the workability and structure of the concrete. The structural strength is important; thirdly, for concrete materials with different proportions (such as different sand ratios and aggregate particle sizes) and different slumps, fixed blades cannot adjust the mixing intensity and mixing range; at the same time, most existing concrete mixing devices directly put the raw materials into the mixing drum without setting up effective pretreatment components. When large particles or impurities are mixed in the raw materials, these foreign objects will directly enter the mixing process, which is not only difficult to be mixed and dispersed, but may also scratch the mixing blades and block the discharge port. At the same time, it will lead to uneven local composition of concrete, increase the probability of rework, and affect the construction progress. Therefore, it is necessary to develop a concrete mixing device with movable blades. Summary of the Invention

[0004] To address the aforementioned defects and problems, this invention provides a concrete mixing device with movable blades, aiming to solve the problems of numerous dead zones, severe material segregation, unadjustable mixing parameters, and lack of raw material pretreatment in traditional concrete mixing devices. This achieves efficient and uniform mixing, improves concrete quality and mixing efficiency, and reduces maintenance costs.

[0005] The solution adopted by this invention to solve its technical problem is as follows: a concrete mixing device with movable blades, including a mixing drum and a mixing shaft, the mixing shaft being arranged axially along the mixing drum, and one end of the mixing shaft being connected to a drive motor; it also includes a vibrating screen assembly and an adjusting mixing assembly; the vibrating screen assembly includes a vibrating frame, a support spring, and a vibrating motor; the vibrating frame is connected to the top of the mixing drum through the support spring; a screen is installed inside the vibrating frame; the output end of the vibrating frame corresponds vertically to the input end of the top of the mixing drum; the vibrating motor is installed on the vibrating frame; the adjusting mixing assembly includes movable mixing blades, a telescopic drive unit, and a drive unit; the movable mixing blades are installed on the outer peripheral sidewall of the mixing shaft through a hinge structure and are distributed at intervals along the axial and circumferential directions of the mixing shaft; the movable mixing blades include a fixed section, a telescopic section, and blades; the telescopic section is arranged within the fixed section, and the far end of the telescopic section is connected to the blades; the telescopic drive unit is arranged within the fixed section; the telescopic drive unit is connected to the telescopic section to drive it to extend and retract along the length direction of the fixed section; the drive unit is connected to the movable mixing blades and is used to drive the movable mixing blades to rotate around the hinge structure.

[0006] Furthermore, the hinge structure includes a blade mounting seat and a hinge shaft. The blade mounting seat is disposed on the stirring shaft, and the fixed section of the movable stirring blade is hinged to the blade mounting seat through the hinge shaft. The axis of the hinge shaft is perpendicular to the axis of the stirring shaft.

[0007] Furthermore, the drive unit includes a hydraulic telescopic rod, one end of which is hinged to the stirring shaft, and the other end is hinged to the middle of the fixed section of the movable stirring blade.

[0008] Furthermore, the telescopic drive unit includes an electric actuator, which is disposed within the fixed section of the movable stirring blade, and the output end of the electric actuator is connected to the telescopic section.

[0009] Furthermore, the stirring shaft is a hollow structure, and a rotary joint is provided at the end of the stirring shaft.

[0010] Furthermore, several guide plates are provided on the inner wall of the mixing drum, and the guide plates extend along the axial direction of the mixing drum, with an included angle of 90 degrees between adjacent guide plates.

[0011] Furthermore, the surface of the movable stirring blade is provided with a wear-resistant coating, which is a tungsten carbide coating.

[0012] Furthermore, it also includes a material sensor, which is installed inside the mixing drum to monitor the mixing status of the concrete.

[0013] 1. By adjusting the mixing components, the blades can rotate at an angle and extend or retract in length. The mixing posture of the blades can be dynamically adjusted according to the material characteristics (aggregate particle size, slump) and mixing requirements, eliminating dead angles in the mixing drum wall and shaft core area. The diverse blade postures enable the material to form a complex flow path, improving the stability of concrete quality.

[0014] 2. By collecting uniformity and slump parameters in real time through material sensors, the controller automatically adjusts the mixing shaft speed, blade angle and extension length to achieve dynamic matching of raw material characteristics and mixing parameters, without the need for manual experience intervention; shortening the concrete mixing time and avoiding mixing defects caused by improper parameters.

[0015] 3. The vibrating screen assembly enables simultaneous screening and feeding of raw materials, removing large particles and impurities, avoiding mixing defects caused by uneven raw materials, laying the foundation for subsequent uniform mixing, and reducing rework costs caused by raw material problems. Attached Figure Description

[0016] Figure 1 This is one of the schematic diagrams of the overall structure of the present invention.

[0017] Figure 2 This is the second schematic diagram of the overall structure of the present invention.

[0018] Figure 3 This is a schematic diagram of the internal structure of the stirring tank.

[0019] Figure 4 A schematic diagram of the structure for adjusting the stirring assembly.

[0020] Figure 5 This is a schematic diagram of the structure of a movable stirring blade.

[0021] Figure 6 This is a schematic diagram of the structure of a vibrating screen assembly.

[0022] In the diagram: 1-mixing drum, 2-mixing shaft, 3-drive motor, 4-vibrating screen assembly, 41-vibrating frame, 42-screen, 43-support spring, 44-vibrating motor, 51-movable mixing blade, 511-fixed section, 512-telescopic section, 513-blade, 52-electric actuator, 53-hydraulic telescopic rod, 54-blade mounting base. Detailed Implementation

[0023] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0024] Example 1: Existing concrete mixing devices mostly have fixed-installation blades, meaning the blades are rigidly connected to the mixing shaft, and the angle and length of the blades cannot be adjusted. This fixed-blade structure has the following drawbacks: First, the fixed blade angle and length result in a single mixing trajectory, failing to cover the corner areas between the inner wall of the mixing drum and the mixing shaft, the vicinity of the drum wall, and the core area, easily creating blind spots in the mixing process, leading to insufficient local mixing and poor uniformity of the concrete. Second, the fixed mixing trajectory of the fixed blades causes the material to only form a unidirectional circumferential flow or a simple axial flow within the mixing drum, lacking complex convection and shearing effects, which affects the workability and structural strength of the concrete. Third, for concrete materials with different mix proportions (such as different sand ratios and aggregate particle sizes) and different slumps, the fixed blades cannot adjust the mixing intensity and range. Furthermore, most existing concrete mixing devices directly feed raw materials into the mixing drum without effective pretreatment components. When large particles or impurities are mixed into the raw materials, these foreign objects directly enter the mixing process, not only being difficult to disperse but also potentially scratching the mixing blades, clogging the discharge port, and causing uneven local composition of the concrete.

[0025] To address the aforementioned issues, this embodiment discloses a concrete mixing device with movable blades, aiming to solve the technical problems of traditional mixing devices, such as numerous dead zones, severe material segregation, unadjustable mixing parameters, and lack of raw material pretreatment. Its core architecture consists of four parts: a mixing body, a vibrating screen component, an adjusting mixing component, and a control module. The components work together to achieve efficient, uniform, and intelligent concrete mixing operations.

[0026] The mixing body includes a horizontal cylindrical mixing drum 1 and a mixing shaft 2 that runs through the mixing drum 1 along its axial direction. The mixing drum 1 is welded from Q345 low-carbon alloy steel plate, and the inner wall is polished to reduce material adhesion. The mixing shaft 2 is a hollow structure made of 40Cr alloy tempered steel. One end of the shaft is connected to the drive motor 3 via a coupling, and the other end extends out of the mixing drum 1 and is equipped with a rotary joint. This rotary joint can achieve a dynamic sealed connection between the hydraulic oil, control harness and the rotating mixing shaft 2, providing a power and signal transmission channel for adjusting the mixing components.

[0027] The vibrating screen assembly 4 is located directly above the feed inlet at the top of the mixing drum 1. It is used to pre-treat the concrete raw materials, remove lumps and impurities, and achieve uniform material distribution. The feed inlet at the top of the mixing drum 1 is connected to a conical hopper. The conical hopper cooperates with the vibrating screen assembly 4 for feeding. The inner wall of the conical hopper is coated with polytetrafluoroethylene to prevent the raw materials from adhering and to ensure that the screened raw materials fall accurately into the mixing drum 1.

[0028] The vibrating screen assembly 4 includes a vibrating frame 41, support springs 43, a vibrating motor 44, and a screen 42. The vibrating frame 41 adopts a rectangular frame structure and is made of Q235B steel. A double-layer screen 42 is fixed to the inner side of the frame by bolts. The upper screen 42 has a hole diameter of 15mm (for filtering large particle clumps), and the lower screen 42 has a hole diameter of 5mm (for secondary filtration of impurities). The distance between the two layers of screens 42 is set to 80mm, and a rubber buffer pad is installed between the screen 42 and the vibrating frame 41 to reduce noise and wear of the screen 42 during the screening process. The four corners of the vibrating frame 41 are connected to the top of the mixing drum 1 by support springs 43. The support springs 43 are cylindrical helical compression springs, which can realize the elastic support of the vibrating frame 41 and ensure the stability of the vibration amplitude. The vibrating motor 44 is fixed to the side of the vibrating frame 41 by a motor base to facilitate the screening of raw materials along the screen 42.

[0029] The adjustment and stirring assembly is the core innovative part of the device. It is installed on the outer peripheral side wall of the stirring shaft 2 and is used to realize the angle adjustment and length extension of the stirring blades 513. It includes movable stirring blades 51, extension and retraction drive unit, drive unit and hinge structure. It is divided into 3 groups along the axial direction of the stirring shaft 2, with 2 blades evenly distributed in each group along the circumference of the stirring shaft 2. The blades 513 of adjacent groups are staggered by 30° in the axial direction to avoid material interference during the stirring process.

[0030] The hinge structure is used to realize the rotational connection between the movable stirring blade 51 and the stirring shaft 2. This hinge structure can ensure the stable rotation of the movable stirring blade 51 and provide reliable support for angle adjustment. It includes a blade mounting seat 54 and a hinge shaft. The blade mounting seat 54 is a U-shaped block structure, which is fixed to the outer periphery of the stirring shaft 2 by welding. Coaxial hinge holes are opened on both sides of the blade mounting seat 54. The hinge shaft is a stepped shaft. The hinge shaft passes through the hinge hole of the blade mounting seat 54 and is hinged to the fixed section 511 of the movable stirring blade 51. The axis of the hinge shaft is perpendicular to the axis of the stirring shaft 2. A self-lubricating bearing is fitted at the hinge to reduce the rotational friction coefficient and ensure the smoothness and stability of the blade 513 angle adjustment.

[0031] The movable stirring blade 51 adopts a two-section telescopic structure, including a fixed section 511, a telescopic section 512, and a blade body 513. The fixed section 511 is a hollow rectangular steel tube, one end of which is hinged to a hinge shaft, and has a guide groove along its length inside. The telescopic section 512 is a rectangular steel rod adapted to the fixed section 511. One end of the rod is inserted into the guide groove of the fixed section 511 and can slide along the guide groove. The other end is welded to the blade body 513. The blade body 513 is an arc-shaped plate structure (the radius of curvature is adapted to the curvature of the inner wall of the stirring drum 1). The material is NM450 wear-resistant steel, and the surface is coated with a 0.3mm thick tungsten carbide coating through plasma spraying. This coating can improve the wear resistance of the blade 513 by 3-5 times, effectively extend the service life of the blade 513, and reduce maintenance costs.

[0032] The telescopic drive unit is located inside the fixed section 511 and is used to drive the telescopic section 512 to extend and retract along the length of the fixed section 511. It uses a miniature electric actuator 52. The cylinder of the electric actuator 52 is fixed to the inner bottom of the fixed section 511 by bolts. The output end of the electric actuator 52 is connected to the end of the telescopic section 512 inserted into the fixed section 511 through a flange. The control harness of the electric actuator 52 is inserted into the hollow channel of the mixing shaft 2 and connected to an external controller through a rotary joint. Through the telescopic action of the electric actuator 52, the extension length of the blade 513 body can be precisely adjusted, so that the mixing radius can be adjusted to adapt to different mixing radius requirements of concrete raw materials and expand the mixing coverage area.

[0033] The drive unit is used to drive the movable stirring blade 51 to rotate around the hinge shaft, thereby adjusting the angle of the blade 513. It includes a hydraulic telescopic rod 53 and a hydraulic control system. The cylinder end of the hydraulic telescopic rod 53 is connected to the outer peripheral wall of the stirring shaft 2 through a ball joint. The push rod end of the hydraulic telescopic rod 53 is connected to the middle position of the fixed section 511 of the movable stirring blade 51 through a ball joint. The inlet and return oil pipes of the hydraulic telescopic rod 53 pass through the hollow channel of the stirring shaft 2 and are connected to an external hydraulic station through a rotary joint. An electromagnetic proportional valve is provided on the hydraulic pipe. The electromagnetic proportional valve is electrically connected to the controller. The extension and retraction of the hydraulic telescopic rod 53 can be precisely adjusted by controlling the flow of hydraulic oil, thereby achieving stepless adjustment of the blade 513 angle, meeting the angle adjustment requirements under different working conditions, and realizing the stirring of different material characteristics (such as dry materials, wet materials, and aggregate particle size).

[0034] The material sensor is used to monitor the mixing status of concrete in the mixing drum 1 in real time. A multi-functional concrete sensor is selected. The sensor is installed in the middle of the inner wall of the mixing drum 1 by a bracket. Its detection end extends into the inside of the mixing drum 1. It can simultaneously collect the uniformity of concrete (monitored by impedance change), slump (monitored by viscosity sensor) and temperature parameters. The signal output line of the sensor passes through the sealing sleeve on the outer wall of the mixing drum 1 and is electrically connected to the external controller. The controller automatically generates control commands based on the real-time data collected by the material sensor, and adjusts the speed of the drive motor 3, the angle of the hydraulic telescopic rod 53 and the extension length of the electric push rod 52 to realize intelligent dynamic adjustment of mixing parameters.

[0035] Workflow: After starting the device, the vibration motor 44 is turned on first. The excitation force generated by the vibration motor 44 drives the vibration frame 41 and the screen 42 to vibrate at high frequency. The concrete raw materials (cement, sand, water, admixtures, etc.) are put into the screen 42 of the vibration frame 41. Under the action of vibration, the raw materials slide along the screen 42. Large particles (particle size > 15 mm) are intercepted by the upper screen 42, and impurities (particle size 5-15 mm) are intercepted by the lower screen 42. The raw materials that meet the requirements (particle size < 5 mm) pass through the double screen 42 and fall into the mixing drum 1 through the guide hopper, realizing the pretreatment and uniform distribution of the raw materials.

[0036] Based on the strength grade of the concrete to be mixed (such as C30, C40) and the characteristics of the raw materials (such as aggregate particle size and sand ratio), the initial mixing parameters are input through the human-machine interface of the controller. According to the initial parameters, the controller sends control signals to the electric actuator 52 and the hydraulic telescopic rod 53. The electric actuator 52 drives the telescopic section 512 to extend to the set length, and the hydraulic telescopic rod 53 drives the blade 513 to rotate to the set angle, thus completing the parameter initialization before mixing.

[0037] The drive motor 3 is started, and the stirring shaft 2 drives the movable stirring blades 51 to rotate synchronously. The blades 513 shear and tumble the raw materials in the mixing drum 1. At the same time, the material sensor collects the uniformity and slump parameters of the concrete in real time and transmits the data to the controller. When the controller detects that the uniformity of the concrete is lower than the set threshold (e.g., impedance change rate < 5%), it controls the hydraulic telescopic rod 53 to extend, increasing the angle of the blades 513 to 25° to enhance the axial convection effect of the material. It also controls the electric actuator 52 to drive the telescopic section 512 to extend, increasing the mixing radius and expanding the mixing coverage. When the slump is detected to be greater than the set value (e.g., > 180 mm), the speed of the stirring shaft 2 is increased to enhance the shearing effect of the material and reduce segregation.

[0038] When the material sensor detects that the uniformity and slump of the concrete have reached the set requirements for 5 consecutive seconds (uniformity impedance change rate 28%, slump 120-160mm), the controller determines that the mixing is complete and issues an audible and visual prompt signal. At this time, the control drive motor 3 stops rotating, the electric actuator 52 drives the telescopic section 512 to retract to its shortest length, and the hydraulic telescopic rod 53 drives the blade 513 to rotate, reducing material adhesion during unloading. The discharge valve on one side of the mixing drum 1 is opened, and the concrete is unloaded under its own gravity. After unloading is completed, the discharge valve is closed, and the device enters the preparation state for the next batch of mixing.

[0039] This device, through the coordinated control of the telescopic drive unit and the drive unit, allows for bidirectional adjustment of the blade 513's angle and length. The mixing posture can be flexibly adjusted according to different raw material characteristics. Simultaneously, the vibrating screen component 4 removes lumps and impurities from the raw materials, reducing mixing defects caused by uneven material distribution. Combined with dynamic monitoring by material sensors and automatic adjustment by the controller, a closed-loop control system of raw material pretreatment, dynamic mixing, and parameter optimization is achieved. This embodiment of the movable blade 513 concrete mixing device, through raw material pretreatment by the vibrating screen component 4, multi-functional posture adjustment of the mixing components, and dynamic optimization by the intelligent control module, achieves high efficiency, uniformity, and intelligence in concrete mixing, demonstrating significant technological innovation and practical application value.

[0040] Example 2, a concrete mixing device with movable blades in this embodiment will be described with a focus on the differences from that in Example 1.

[0041] In this embodiment, four guide plates are uniformly arranged axially on the inner wall of the mixing drum 1. The guide plates are rectangular steel plates and are fixedly connected to the inner wall of the mixing drum 1 by welding. The guide plates extend axially along the mixing drum 1, and the included angle between adjacent guide plates is 90°. The material-facing surface of the guide plates is set as an arc structure, which can guide the material to form a spiral upward flow along the inner wall of the mixing drum 1 during the mixing process. Combined with the multi-angle and multi-radius mixing action of the movable mixing blades 51, a complex material flow pattern of axial convection + radial shear + circumferential mixing is formed, which effectively eliminates the mixing dead angle between the inner wall of the mixing drum 1 and the mixing shaft 2 and improves the mixing uniformity.

[0042] The above description is only a preferred embodiment of the present invention and does not limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A concrete mixing device with movable blades, comprising a mixing drum and a mixing shaft, wherein the mixing shaft is arranged axially along the mixing drum, and one end of the mixing shaft is connected to a drive motor for transmission, characterized in that, It also includes a vibrating screening assembly and an adjusting stirring assembly; the vibrating screening assembly includes a vibrating frame, a support spring, and a vibrating motor. The vibrating frame is connected to the top of the stirring drum through the support spring. A screen is installed inside the vibrating frame, and the output end of the vibrating frame corresponds vertically to the input end of the top of the stirring drum. The vibrating motor is installed on the vibrating frame; the adjusting stirring assembly includes movable stirring blades, a telescopic drive unit, and a drive unit. The movable stirring blades are installed on the outer peripheral sidewall of the stirring shaft through a hinge structure and are distributed at intervals along the axial and circumferential directions of the stirring shaft. The movable stirring blades include a fixed section, a telescopic section, and blades. The telescopic section is located within the fixed section, and the far end of the telescopic section is connected to the blades. A telescopic drive unit is located within the fixed section and is connected to the telescopic section to drive it to extend and retract along the length direction of the fixed section. The drive unit is connected to the movable stirring blades and is used to drive the movable stirring blades to rotate around the hinge structure.

2. The concrete mixing device with movable blades according to claim 1, characterized in that, The hinge structure includes a blade mounting seat and a hinge shaft. The blade mounting seat is disposed on the stirring shaft. The fixed section of the movable stirring blade is hinged to the blade mounting seat through the hinge shaft. The axis of the hinge shaft is perpendicular to the axis of the stirring shaft.

3. A concrete mixing device with movable blades according to claim 1, characterized in that, The drive unit includes a hydraulic telescopic rod, one end of which is hinged to the stirring shaft, and the other end is hinged to the middle of the fixed section of the movable stirring blade.

4. A concrete mixing device with movable blades according to claim 1, characterized in that, The telescopic drive unit includes an electric actuator, which is disposed within the fixed section of the movable stirring blade, and the output end of the electric actuator is connected to the telescopic section.

5. A concrete mixing device with movable blades according to claim 1, characterized in that, The stirring shaft is a hollow structure, and a rotary joint is provided at the end of the stirring shaft.

6. A concrete mixing device with movable blades according to claim 1, characterized in that, Several guide plates are provided on the inner wall of the mixing drum. The guide plates extend along the axial direction of the mixing drum, and the included angle between adjacent guide plates is 90 degrees.

7. A concrete mixing device with movable blades according to claim 1, characterized in that, The surface of the movable stirring blade is provided with a wear-resistant coating, which is a tungsten carbide coating.

8. A concrete mixing device with movable blades according to claim 1, characterized in that, It also includes a material sensor, which is installed inside the mixing drum to monitor the mixing status of the concrete.

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