A paddle shaft torque detection device for a three-paddle vertical mixer

Abstract

The application belongs to the technical field of torque detection. The application provides a paddle shaft torque detection device for a three-paddle vertical mixer. The disclosed embodiment can realize fast, accurate and reliable detection of the paddle shaft torque and rotational speed of the mixer by connecting a high-precision torque sensor in series in the power transmission path and integrating a rotational speed measurement function, and by using careful structural design (such as coaxiality guarantee, pressure balance and sealing treatment) to ensure reliable operation of the sensor under complex working conditions, effectively solving the problem of slow response and low accuracy of the hydraulic oil pressure feedback mode in the prior art.

Description

Technical Field

[0001] This disclosure relates to the field of torque detection technology, and more particularly to a blade shaft torque detection device for a three-blade vertical mixer. Background Technology

[0002] In the manufacturing process of composite solid propellants, the mixing process is one of the most dangerous steps, and the vertical mixer is a key piece of equipment for propellant preparation. This equipment uses blades to knead and stir the propellant raw materials to achieve a homogeneous state. Due to the flammable and explosive nature of solid propellants, the torque parameter of the blade shaft during the mixing process is not only a key process parameter related to the quality of the final product, but also a crucial safety parameter directly related to production safety. When the torque reaches or exceeds a preset safety threshold, the mixer system must be able to immediately alarm and stop to avoid safety accidents. Therefore, real-time and accurate monitoring and feedback of the blade shaft torque is essential.

[0003] Currently, most vertical mixers use hydraulic drive for impeller rotation. A hydraulic station drives a hydraulic motor via hydraulic fluid, and the motor's output transmits torque to the impeller through a transmission box. Correspondingly, existing torque detection methods are typically indirect, relying on monitoring hydraulic oil pressure for feedback. Specifically, the output torque of the hydraulic motor is calculated from the oil pressure value based on its model parameters. However, this oil pressure-dependent detection method has significant drawbacks: First, the accuracy of torque calculation is low; changes in oil pressure cannot accurately and quickly reflect the dynamic changes in the actual impeller torque, resulting in poor real-time performance. Second, oil pressure is easily affected by factors such as oil pipe blockage and changes in oil viscosity, further reducing the reliability of the torque calculation results. Even worse, in the investigation of a recent large-scale equipment explosion accident, it was found that the original system's torque data acquisition speed was insufficient, making it impossible to query and trace the instantaneous maximum torque value at the moment of the explosion, thus making it impossible to accurately determine the equipment's condition at the time of the accident.

[0004] Therefore, it is necessary to improve one or more of the problems existing in the above-mentioned related technical solutions.

[0005] It should be noted that this section is intended to provide background or context for the technical solutions of this disclosure as set forth in the claims. The description herein does not constitute an admission that it is prior art simply because it is included in this section. Summary of the Invention

[0006] The purpose of this disclosure is to provide a blade shaft torque detection device for a three-blade vertical mixer, thereby at least partially solving the problems of slow response speed and low torque calculation accuracy in the existing hydraulic oil pressure feedback method.

[0007] According to an embodiment of this disclosure, a blade shaft torque detection device for a three-blade vertical mixer is provided, comprising: The sensor base has a first flange at one end and a second flange at the other end, and the sensor base has a cavity that passes through the first flange and the second flange. The sensor assembly includes a torque sensor, a mounting base, and a sensor adapter shaft. The torque sensor is mounted on the mounting base, which is fixedly mounted on the first flange of the sensor base. The sensor adapter shaft passes through the torque sensor and the mounting base and is rotatable along its central axis. The input end of the gearbox adapter shaft is connected to the output end of the sensor adapter shaft and is located in the cavity of the sensor base. The output end of the gearbox adapter shaft is used to connect to the input end of the gearbox. The output end of the motor adapter shaft is connected to the input end of the sensor adapter shaft, and the input end of the motor adapter shaft is used to connect to the output end of the motor. The cylindrical extension section is sleeved around the sensor assembly and the motor adapter shaft, with one end of the extension section fixedly mounted on the first flange of the sensor base and the other end used for fixed connection with the motor.

[0008] Furthermore, corresponding keyways and keys are provided on the input end of the motor adapter shaft, the output end of the motor adapter shaft and the input end of the sensor adapter shaft, the output end of the sensor adapter shaft and the input end of the gearbox adapter shaft, and the output end of the gearbox adapter shaft.

[0009] Furthermore, the upper end face of the first flange of the sensor base has several evenly distributed grooves, and the grooves are connected to the cavity.

[0010] Furthermore, the side wall of the heightened section component is provided with mounting holes, and a grid head is provided in the mounting holes for leading out the cable of the torque sensor.

[0011] Furthermore, the sidewall of the output end of the motor adapter shaft has a toothed structure, and the number of teeth z in the toothed structure is 15 to 25.

[0012] Furthermore, the side wall of the heightened section component is provided with a countersunk hole, and a proximity switch mounting base is provided in the countersunk hole. A proximity switch is provided in the proximity switch mounting base. The proximity switch periodically detects the signal of the toothed protrusion to calculate the rotational speed.

[0013] Furthermore, the diameter of the input end of the gearbox adapter shaft is larger than the diameter of the output end of the gearbox adapter shaft.

[0014] Furthermore, the diameters of both the input end of the gearbox adapter shaft and the output end of the sensor adapter shaft are smaller than the diameter of the cavity.

[0015] The technical solutions provided by the embodiments of this disclosure may include the following beneficial effects: Accurate and real-time detection: By directly connecting a high-precision torque sensor in series between the motor and the gearbox, the torque at the input end of the blade shaft can be directly and dynamically measured. Compared with the indirect conversion through hydraulic oil pressure, this significantly improves the accuracy of torque detection and the speed of data feedback, providing rapid response conditions for torque over-value alarms and real-time and effective data support for the safety assessment of vertical mixing processes.

[0016] To ensure sensor reliability: A stop-fit ​​structure between the sensor base, the heightened section, and the motor ensures coaxiality of all components, allowing the torque sensor to primarily bear pure torque and avoiding the impact of bending moment on its measurement accuracy and lifespan. Simultaneously, a groove connecting the cavity is provided on the first flange of the sensor base, ensuring pressure balance at both the input and output ends of the torque sensor (both at atmospheric pressure or vacuum), preventing sensor malfunction due to pressure differences, and further improving the stability and reliability of the device.

[0017] Integrated speed measurement function: A toothed structure is set on the motor adapter shaft, and in conjunction with a proximity switch, the speed of the motor output shaft can be monitored in real time while measuring torque. By comparing torque data at different speeds, data support can be provided to determine the optimal stirring speed, which helps to optimize the mixing process. Attached Figure Description

[0018] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure. It is obvious that the drawings described below are merely some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0019] Figure 1 A cross-sectional view of the blade shaft torque detection device of a three-blade vertical mixer blade in an exemplary embodiment of the present disclosure is shown. Figure 2 A cross-sectional view of the sensor base in an exemplary embodiment of this disclosure is shown; Figure 3 A top view of the sensor base in an exemplary embodiment of this disclosure is shown; Figure 4 This diagram illustrates the structure of the sensor assembly in an exemplary embodiment of this disclosure. Figure 5 This diagram illustrates the structure of the gearbox adapter shaft in an exemplary embodiment of this disclosure. Figure 6 A cross-sectional view of the motor adapter shaft in an exemplary embodiment of this disclosure is shown; Figure 7A top view of the motor adapter shaft in an exemplary embodiment of this disclosure is shown; Figure 8 A cross-sectional view of the heightened section component in an exemplary embodiment of this disclosure is shown; Figure 9 A cross-sectional view of the proximity switch mounting base in an exemplary embodiment of the present disclosure is shown.

[0020] In the diagram, 1. Gearbox adapter shaft; 2. Sensor base; 21. First flange; 22. Second flange; 23. Cavity; 24. Groove; 3. Sensor assembly; 31. Torque sensor; 32. Mounting base; 33. Sensor adapter shaft; 4. Elevation section component; 41. Countersunk hole; 42. Mounting hole; 5. Motor adapter shaft; 51. Toothed structure; 6. Gear head; 7. Proximity switch mounting base; 8. Proximity switch; 9. Gearbox; 10. Motor. Detailed Implementation

[0021] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, they are provided so that this disclosure will be more comprehensive and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0022] Furthermore, the accompanying drawings are merely illustrative diagrams of embodiments of this disclosure and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and therefore repeated descriptions of them will be omitted. Some block diagrams shown in the drawings are functional entities and do not necessarily correspond to physically or logically independent entities.

[0023] This example embodiment provides a blade shaft torque detection device for a three-blade vertical mixer. (Reference) Figure 1 , Figure 2 and Figure 4 As shown, the impeller shaft torque detection device for a three-blade vertical mixer may include: The sensor base 2 has a first flange 21 at its first end and a second flange 22 at its second end, and the sensor base 2 has a cavity 23 that passes through the first flange 21 and the second flange 22. The sensor assembly 3 includes a torque sensor 31, a fixed base 32, and a sensor adapter shaft 33. The torque sensor 31 is mounted on the fixed base 32, and the fixed base 32 is fixedly mounted on the first flange 21 of the sensor base 2. The sensor adapter shaft 33 passes through the torque sensor 31 and the fixed base 32 and can rotate along its central axis. The input end of the gearbox adapter shaft 1 is connected to the output end of the sensor adapter shaft 33 and is located in the cavity 23 of the sensor base 2. The output end of the gearbox adapter shaft 1 is used to connect to the input end of the gearbox 9. The output end of the motor adapter shaft 5 is connected to the input end of the sensor adapter shaft 33, and the input end of the motor adapter shaft 5 is used to connect to the output end of the motor 10. The cylindrical extension section 4 is sleeved outside the sensor assembly 3 and the motor adapter shaft 5, with one end of the extension section 4 fixedly mounted on the first flange 21 of the sensor base 2, and the other end used for fixed connection with the motor 10.

[0024] The aforementioned impeller shaft torque detection device for a three-paddle vertical mixer achieves direct and dynamic measurement of the input torque of the impeller shaft by directly connecting a high-precision torque sensor in series between the motor and the gearbox. Compared to the indirect conversion method using hydraulic oil pressure, this significantly improves the accuracy of torque detection and the speed of data feedback, providing rapid response conditions for torque over-limit alarms and real-time and effective data support for safety assessment of the vertical mixing process. By setting a stop-fit ​​structure between the sensor base and the heightened section and motor, the coaxiality of the components is ensured, allowing the torque sensor to primarily bear pure torque, avoiding the influence of bending moment on its measurement accuracy and lifespan. Simultaneously, a groove connecting the cavity is provided on the first flange of the sensor base to ensure pressure balance at both the input and output ends of the torque sensor (both at atmospheric pressure or vacuum), preventing sensor failure due to pressure differences and further improving the stability and reliability of the device. A toothed structure is set on the motor adapter shaft, and in conjunction with a proximity switch, the rotational speed of the motor output shaft can be monitored in real time while measuring torque. By comparing torque data at different speeds, data support can be provided to determine the optimal mixing speed, helping to optimize the mixing process.

[0025] Below, we will refer to Figures 1 to 9 The steps of the blade shaft torque detection device for a three-blade vertical mixer described in this example embodiment will be explained in more detail.

[0026] In one embodiment, the sensor base 2 is generally cylindrical in shape, with a first flange 21 and a second flange 22 at its upper and lower ends, respectively. The sensor base 2 has an internal cavity 23 that penetrates both the first flange 21 and the second flange 22. The second flange 22 of the sensor base 2 has multiple evenly distributed optical holes for fixing the entire base to the gearbox 9 of the mixer using bolts or other fasteners. The first flange 21 has two sets of holes, an inner and an outer set. The inner set consists of evenly distributed threaded holes for fixing the torque sensor 31; the outer set consists of evenly distributed threaded holes for fixing the extension section component 4. Specifically, as shown... Figure 2 and Figure 3As shown, several circumferentially distributed grooves 24 are formed on the upper end face of the first flange 21. These grooves 24 are connected to the cavity 23 inside the sensor base 2. The function of the grooves 24 is to connect the upper and lower cavities of the sensor base 2 (i.e., the cavity 23 and the internal space of the raised section component 4), ensuring that when the gearbox 9 cavity is evacuated, the input and output ends of the torque sensor 31 installed on the sensor base 2 can maintain pressure balance (both at normal pressure or vacuum), preventing the internal components of the sensor from malfunctioning due to pressure difference.

[0027] In one embodiment, such as Figure 4 As shown, the sensor assembly 3 includes a torque sensor 31, a mounting base 32 (a flange portion integrated with the torque sensor 31 for installation), and a sensor adapter shaft 33 (the shaft end of the torque sensor 31). The torque sensor 31 can be a CYB-820S type explosion-proof torque sensor 31 (ExiaIICT6 intrinsically safe explosion-proof rating). This sensor can measure dynamic torque, output a standard current signal of 4-20mA, and has the advantages of high detection accuracy, good stability, and strong anti-interference capability. The torque sensor 31 is precisely fixed to the first flange 21 of the sensor base 2 using bolts through the stop and aperture on its flange. The sensor adapter shaft 33 passes through the torque sensor 31 and its mounting base 32 and can rotate freely along its central axis.

[0028] In one embodiment, the gearbox adapter shaft 1, its input end ( Figure 5 The larger diameter end on the left side has an inner hole and a keyway, which connects to the output end of the torque sensor 31 (i.e., the output end of the sensor adapter shaft 33) via a key, functioning as a coupling. The output end of the gearbox adapter shaft 1 ( Figure 5 The smaller diameter end (on the right side) has a keyway for connecting to the input end of the mixer gearbox 9. The entire gearbox adapter shaft 1 is housed within the cavity 23 of the sensor base 2. To ensure its free rotation, the diameters of both the input end of the gearbox adapter shaft 1 and the output end of the sensor adapter shaft 33 are designed to be smaller than the diameter of the cavity 23 of the sensor base 2. Furthermore, the diameter of the input end of the gearbox adapter shaft 1 is larger than its output end diameter to accommodate the different dimensions of the torque sensor 31 output shaft and the gearbox 9 input shaft.

[0029] In one embodiment, the motor adapter shaft 5 has an inner hole and a keyway at its output end, which is keyed to the input end of the torque sensor 31 (i.e., the input end of the sensor adapter shaft 33). Its input end also has an inner hole and a keyway for connecting to the output shaft of the hydraulic motor (i.e., motor 10). Figure 6 and Figure 7As shown, a toothed structure 51 is machined on the outer circumference of the side of the motor adapter shaft 5 where it connects to the torque sensor 31 (i.e., the output end). The number of teeth z of this toothed structure 51 can be selected as needed, for example, 15-25 teeth. This toothed structure 51 is used in conjunction with the proximity switch 8 for speed measurement.

[0030] In one embodiment, such as Figure 8 As shown, the heightened section component 4 has a cylindrical structure and is fitted around the sensor assembly 3 and the motor adapter shaft 5. The lower end face of the heightened section component 4 is annular and has multiple evenly distributed optical holes, which are fixedly connected to the outer ring threaded holes of the first flange 21 of the sensor base 2 by bolts. The upper end face of the heightened section component 4 is also annular and has multiple evenly distributed threaded holes for fixing and installing the hydraulic motor. A countersunk hole 41 is also provided on the inner side of the upper end face for mating with the stop of the hydraulic motor to ensure coaxiality during installation. Through the stop mating between the sensor base 2, the heightened section component 4, and the hydraulic motor, the coaxiality error of the entire device from the gearbox 9 to the hydraulic motor can be controlled within a very small range (e.g., ≤0.02mm), so that the torque sensor 31 mainly bears pure torque and avoids the negative impact of bending moment.

[0031] In one embodiment, a threaded mounting hole 42 (i.e., mounting hole 42) is provided on the side wall of the raised section component 4 for mounting the grate head 6. The grate head 6 is a standard cable connector used to safely and sealedly lead the cable of the torque sensor 31 out from inside the raised section component 4. Above the mounting hole 42 of the grate head 6, a countersunk hole 41 is also provided for mounting the proximity switch mounting base 7. The structure of the proximity switch mounting base 7 is as follows: Figure 9 As shown, the left side has a threaded hole for mounting the proximity switch 8, the middle has a flange for self-fixation, and the right side has an external thread for connecting the explosion-proof hose connector. The proximity switch 8 is an inductive proximity switch, with its detection end aligned with the toothed structure 51 on the motor adapter shaft 5. During installation, the position needs to be adjusted to ensure that the proximity switch 8 can detect the protruding part of the toothed structure 51, but not the root part. When the hydraulic motor drives the motor adapter shaft 5 to rotate, the proximity switch 8 will periodically output pulse signals. By calculating the number of pulses per unit time or the time interval between adjacent pulses, the output shaft speed of the hydraulic motor can be calculated. The calculation formula is: , where n is the output shaft speed of the hydraulic motor (r / min), z is the number of teeth of the tooth structure 51, and t is the interval (ms) during which the proximity switch 8 detects the protruding part.

[0032] In actual torque measurement, the relationship between the actual current value A output by torque sensor 31 and the actual torque value T of the hydraulic motor output shaft is: T = (A-12)L / 8, where L is the range of torque sensor 31 (Nm). When the calculated value is negative, it indicates that the hydraulic motor is rotating in the reverse direction.

[0033] In one embodiment, to prevent external air from seeping into the device when a vacuum operation is required in the gearbox 9 cavity, sealing rings are provided between the sensor base 2, the extension section component 4, and the mounting surfaces of the hydraulic motor, etc. The threaded holes between the flange head 6 and the extension section component 4, as well as the connections between the proximity switch mounting base 7 and other components, are sealed with sealant or sealing tape to ensure the overall sealing performance of the device.

[0034] In summary, the blade shaft torque detection device for a three-blade vertical mixer provided in this application, by connecting a high-precision torque sensor in series in the power transmission path and integrating a speed measurement function, and by employing a meticulous structural design (such as ensuring coaxiality, pressure balance, and sealing treatment) to ensure reliable operation of the sensor under complex working conditions, effectively solves the problems of slow response and low accuracy of the hydraulic oil pressure feedback method in the prior art, and realizes rapid, accurate, and reliable detection of the mixer blade shaft torque and speed.

[0035] In summary, the blade shaft torque detection device for a three-blade vertical mixer provided in this application, by connecting a high-precision torque sensor in series in the power transmission path and integrating a speed measurement function, and by employing a meticulous structural design (such as ensuring coaxiality, pressure balance, and sealing treatment) to ensure reliable operation of the sensor under complex working conditions, effectively solves the problems of slow response and low accuracy of the hydraulic oil pressure feedback method in the prior art, and realizes rapid, accurate, and reliable detection of the mixer blade shaft torque and speed.

[0036] It should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise" in the above description indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this disclosure and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this disclosure.

[0037] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of this disclosure, "a plurality of" means two or more, unless otherwise explicitly specified.

[0038] In the embodiments of this disclosure, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this disclosure according to the specific circumstances.

[0039] In embodiments of this disclosure, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0040] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this disclosure. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0041] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the appended claims.

Claims

1. A blade shaft torque detection device for a three-blade vertical mixer, characterized by, include: The sensor base has a first flange at one end and a second flange at the other end, and a cavity through the first flange and the second flange is provided inside the sensor base; wherein, there are several evenly distributed grooves on the upper end face of the first flange of the sensor base, and the grooves are connected to the cavity. The sensor assembly includes a torque sensor, a mounting base, and a sensor adapter shaft. The torque sensor is mounted on the mounting base, which is fixedly mounted on the first flange of the sensor base. The sensor adapter shaft passes through the torque sensor and the mounting base and is rotatable along its central axis. The input end of the gearbox adapter shaft is connected to the output end of the sensor adapter shaft and is located in the cavity of the sensor base. The output end of the gearbox adapter shaft is used to connect to the input end of the gearbox. The output end of the motor adapter shaft is connected to the input end of the sensor adapter shaft, and the input end of the motor adapter shaft is used to connect to the output end of the motor. The cylindrical extension section is sleeved around the sensor assembly and the motor adapter shaft, with one end of the extension section fixedly mounted on the first flange of the sensor base and the other end used for fixed connection with the motor.

2. The blade shaft torque detection device for a three-blade vertical mixer according to claim 1, characterized in that, The input end of the motor adapter shaft, the output end of the motor adapter shaft and the input end of the sensor adapter shaft, the output end of the sensor adapter shaft and the input end of the gearbox adapter shaft, and the output end of the gearbox adapter shaft are all provided with corresponding keyways and keys.

3. The blade shaft torque detection device for a three-blade vertical mixer according to claim 1, characterized in that, The side wall of the heightened section component is also provided with mounting holes, and a grid head is provided in the mounting holes. The grid head is used to lead out the cable of the torque sensor.

4. The blade shaft torque detection device for a three-blade vertical mixer according to claim 1, characterized in that, The sidewall of the output end of the motor adapter shaft has a toothed structure with 15 to 25 teeth.

5. The blade shaft torque detection device for a three-blade vertical mixer according to claim 4, characterized in that, The side wall of the heightened section component is provided with a countersunk hole, and a proximity switch mounting base is provided in the countersunk hole. The proximity switch is provided in the proximity switch mounting base. The proximity switch periodically detects the signal of the toothed protrusion to calculate the rotational speed.

6. The blade shaft torque detection device for a three-blade vertical mixer according to claim 1, characterized in that, The diameter of the input end of the gearbox adapter shaft is larger than the diameter of the output end of the gearbox adapter shaft.

7. The blade shaft torque detection device for a three-blade vertical mixer according to claim 1, characterized in that, The diameters of the input end of the gearbox adapter shaft and the output end of the sensor adapter shaft are both smaller than the diameter of the cavity.

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