Temperature difference assembling device and method for interference shaft assembly of submersible electric pump

Abstract

The invention relates to a temperature difference assembly method and device for an interference shaft assembly of a submersible electric pump, which are mainly applied to the field of assembly of water pump shaft assemblies, in particular to the submersible electric pump, and the traditional assembly method adopts an induction heater to expand an inner hole of a coupling and then install a pump shaft, which has many defects. For example, electric energy is wasted, efficiency is low, occupied space is large, product consistency is poor, and operation risk is high. The core of the device is a semiconductor cold and hot module, a semiconductor chilling plate of the semiconductor cold and hot module generates a heating and refrigerating surface, and components such as a heat conduction module, a cold conduction module and a heat preservation shell work cooperatively. During assembly, the coupler and the pump shaft are mounted and positioned firstly, the semiconductor chilling plate power supply is started to change the sizes of the coupler and the pump shaft, and then assembly is completed through driving parts such as an electric cylinder. According to the method, the energy utilization rate and the production efficiency are effectively improved, the field utilization is optimized, the product consistency is guaranteed, the operation risk is reduced, the key problems of a traditional method are solved, and remarkable innovativeness and practical value are achieved.

Description

Technical Field

[0001] The invention relates to the assembly of interference fit shaft parts, and in particular to a device and method for assembling interference fit shaft parts with temperature difference of a submersible electric pump. Background Art

[0002] In the field of mechanical assembly, in the process of assembling shaft fittings of water pumps, especially submersible electric pumps, the assembly of interference-fit shaft fittings has always been a key link. The traditional temperature difference assembly method of interference-fit shaft fittings usually relies on an induction heater to expand the inner hole of the coupling and then install the pump shaft.

[0003] This conventional assembly method has many disadvantages. In terms of the operation process, the coupling needs to be placed in the heater coil first, and then the heater is started. After the coupling is heated and expanded to a suitable degree, the pump shaft is manually placed, and then the heater is turned off. After the shaft coupling cools down, it is taken out and placed in a designated area for natural cooling. The whole process is extremely cumbersome. For example, in the hot-loading process, the staff is required to place the coupling in the middle of the heating coil of the high-frequency induction heater and heat it to 550°-630°, and then press it vertically into the pump shaft to the bottom, remove the shaft coupling after the temperature drops, and then place it in a designated area to cool for 1 hour.

[0004] More importantly, in this process, due to the lack of precise temperature control and automated operation mechanisms, product quality is difficult to guarantee. Workers can often only rely on experience to judge whether the coupling has reached the target heating value and whether the shaft parts have been cooled down. This leads to poor product consistency, and different batches of shaft parts may have large differences in assembly accuracy and performance. Moreover, high-temperature operation increases the operating risks of workers, making it easy to cause safety accidents such as burns, and also makes assembly efficiency low, seriously affecting production progress. In addition, traditional induction heater equipment is large in size and occupies more site space, which is not conducive to the rational planning and utilization of production sites, and increases the production costs of enterprises. Summary of the invention

[0005] In view of the above-mentioned defects of the prior art, the present invention first provides a temperature difference assembly device for an interference fit shaft of a submersible electric pump, comprising: Semiconductor cooling and heating module, which has a built-in semiconductor cooling sheet, and the semiconductor cooling sheet has a vacuum cavity insulation structure inside, and generates a heating surface and a cooling surface at both ends through the Peltier effect, thereby realizing cooling and heating functions; A heat conduction module is installed on the heating surface of the semiconductor refrigeration sheet. The heat conduction module is made of a ceramic material with high thermal conductivity and low thermal expansion coefficient, and silicone grease is coated between the heat conduction module and the semiconductor refrigeration sheet for efficient heat transfer. A cooling module is arranged on the cooling surface of the semiconductor cooling sheet. The cooling module is made of a ceramic material with high thermal conductivity and low thermal expansion coefficient, and silicone grease is coated between the module and the semiconductor cooling sheet to efficiently transfer cold. The heat insulation shell is installed on the outside of the heat conduction module to play a role in heat insulation and reduce heat loss; The cold insulation shell is installed outside the cooling module to play a role of heat insulation and reduce the loss of cold. The hot insulation shell and the cold insulation shell are fastened by stopper positioning and fastening components, and at the same time, the heat conduction module, the semiconductor refrigeration sheet and the cooling module are pressed to ensure that the components are tightly combined; A coupling guide block is installed on one side of the heat insulation shell and is used to accurately guide the coupling so that it can be accurately installed into the heating end; The pump shaft guide block is installed on one side of the cold insulation shell and is used to accurately guide the pump shaft so that it can be accurately installed in the refrigeration end.

[0006] Furthermore, it also includes a lifting platform, and the semiconductor hot and cold module is fixed on the lifting platform.

[0007] The present invention also provides a temperature difference assembly method for an interference fit shaft of a submersible electric pump, comprising the following steps: (i) Install the coupling on the coupling fixture, place the pump shaft on the pump shaft placement block and fix it with the pump shaft fixing clamp, so that the coupling and pump shaft are in the initial preparation state; (ii) The drive coupling is installed into the heating end through the central guide hole of the coupling guide block, and the drive pump shaft is installed into the cooling end through the central guide hole of the pump shaft guide block, and the installation is confirmed to be in place through monitoring by the distance sensor to ensure the accuracy of assembly; (iii) Start the DC power supply of the semiconductor refrigeration sheet, so that the pump shaft installation part is cooled by the cooling module, and the inner hole of the coupling assembly is heated by the heat conduction module, and the characteristics of the semiconductor refrigeration sheet are used to realize the cold contraction of the pump shaft and the thermal expansion of the coupling; (IV) Drive the coupling and pump shaft back 300mm, lower the semiconductor hot and cold module, move the coupling to insert the pump shaft into its hole, wait for a while for the shaft parts to be tightly fitted, then remove the shaft parts to complete the assembly process; (V) Return the coupling and pump shaft to their original positions, lift the semiconductor heating and cooling module, and prepare for the next assembly.

[0008] Furthermore, in the step of cooling the pump shaft installation portion and heating the coupling assembly inner hole portion, i.e., step (iii) of the interference fit shaft temperature difference assembly method, the pump shaft outer diameter dimension is controlled to shrink and the coupling inner diameter dimension is controlled to expand until the pump shaft outer diameter dimension is smaller than the coupling inner hole dimension to satisfy the clearance fit, thereby ensuring that the two can achieve a tight fit.

[0009] Furthermore, in the step of confirming that the coupling and the pump shaft are installed in place, a judgment is made through the built-in pressure sensor of the electric cylinder to ensure that the assembly is in place.

[0010] Furthermore, after heating and freezing are completed, the electric cylinder drives the coupling and the pump shaft backward. After the lifting platform drives the semiconductor hot and cold module to descend to the bottom of the workbench, the electric cylinder drives the coupling to move and insert the pump shaft into the inner hole of the coupling to complete the tight fitting of the shaft parts.

[0011] Technical Effects 1. Efficient use of energy: The present invention uses the unique characteristic of semiconductor refrigeration sheet to generate hot and cold ends at the same time, realizing the synchronous contraction of the pump shaft end and the thermal expansion of the coupling end. Compared with the traditional heating and cooling methods, it greatly improves the energy utilization rate, avoids energy waste, and effectively reduces the energy consumption cost in the assembly process.

[0012] 2. Significantly improved production efficiency: With the advantage that the cooling capacity and heating capacity of the semiconductor refrigeration plate are basically the same, the coupling can be quickly cooled after being installed on the pump shaft, greatly shortening the assembly cycle. The lengthy process of natural cooling of the shaft assembly for 1 hour in the traditional assembly method has been streamlined, making a qualitative leap in production efficiency, helping enterprises to increase production capacity and enhance market competitiveness.

[0013] 3. Optimized site utilization: The overall structure of the device is compact and small, eliminating the bulky size of traditional large induction heaters. This design allows it to be easily carried to a designated location on the production line for assembly, reducing the need for large dedicated sites, effectively improving the utilization rate of production sites, and saving valuable space resources for enterprises.

[0014] 4. Stable and consistent product quality: The semiconductor cooling chip has the characteristic of fixed temperature difference, which can ensure the stable and precisely controllable temperature of the hot end and the cold end during the assembly process. This effectively avoids the coupling from being burned due to excessive temperature, and ensures that the assembly conditions of each shaft joint are the same, thereby ensuring the overall consistency of the product, improving the quality and reliability of the product, and reducing the scrap rate of the product.

[0015] 5. Reduced operational risks: Since the shaft parts cool down quickly after assembly, the time they are in a dangerous high-temperature state is greatly shortened, reducing the risk of people being scalded by the shaft parts that are cooling down. This provides a safer working environment for operators, meets the requirements of safe production, and helps companies reduce potential losses caused by safety accidents. The concept, specific structure and technical effects of the present invention will be further described below in conjunction with the accompanying drawings to fully understand the purpose, characteristics and effects of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a three-dimensional view of a semiconductor hot and cold module in a preferred embodiment of the present invention; Figure 2 yes Figure 1 A cross-sectional view of Figure 3 It is a three-dimensional view of a temperature difference assembly device for an interference fit shaft of a submersible electric pump in a preferred embodiment of the present invention in a first working state; Figure 4 It is a stereoscopic view of a temperature difference assembly device of an interference fit shaft of a submersible electric pump in a preferred embodiment of the present invention in a second working state. DETAILED DESCRIPTION

[0017] The following describes several preferred embodiments of the present invention with reference to the drawings in the specification, so that the technical content is clearer and easier to understand. The present invention can be embodied in many different forms of embodiments, and the protection scope of the present invention is not limited to the embodiments mentioned in the text.

[0018] In the drawings, components with the same structure are indicated by the same numerical reference numerals, and components with similar structures or functions are indicated by similar numerical reference numerals. The size and thickness of each component shown in the drawings are arbitrarily shown, and the present invention does not limit the size and thickness of each component. In order to make the illustration clearer, the thickness of the components is appropriately exaggerated in some places in the drawings.

[0019] The assembly site is located indoors, the room temperature is 20°C, and the pump shaft and coupling are usually stored at room temperature. The pump shaft diameter d is φ16mm, the length is 200mm, the material is stainless steel 2205, and the thermal expansion coefficient is α 泵轴 11.2×10 -6 / K; The inner diameter of the coupling is φ15.99mm, the depth is 30mm, the material is stainless steel 316L, the thermal expansion coefficient is α 联轴器 17.3×10 -6 / K; The pump shaft and the coupling are interference fit, and the interference is 0.01mm. In order to shorten the assembly process, the assembly parts can be placed in a cold storage at a temperature below -20℃ for more than 6 hours in advance.

[0020] The core component of the temperature difference assembly device for the interference fit shaft of the submersible electric pump according to the present invention is a semiconductor cooling and heating module. Figure 1As shown, a suitable semiconductor cooling sheet 6 is selected, and a vacuum cavity heat insulation structure is used inside the semiconductor cooling sheet 6. This structure can effectively prevent the heat from the heating surface from being transferred to the cooling surface, and ensure the independence of the hot and cold ends. The heat conduction module 5 is installed on the heating surface of the semiconductor cooling sheet 6, and the cooling module 7 is installed on the cooling surface. During the installation process, silicone grease is evenly applied between the semiconductor cooling sheet 6 and the heat conduction module 5 and the cooling module 7 to enhance the heat conduction effect. The heat conduction module 5 and the cooling module 7 are made of ceramic materials with high thermal conductivity and low thermal expansion coefficient to prevent the components from being stuck due to thermal expansion during heat conduction.

[0021] See also Figure 1 , Figure 2 A heat-insulating shell 4 is installed on the outside of the heat-conducting module 5, and a cold-insulating shell 8 is installed on the outside of the cold-conducting module 7. The shells are positioned by stoppers and fastened with bolts and nuts 13. During the fastening process, it is ensured that the heat-insulating shell 4 and the cold-insulating shell 8 can simultaneously press the heat-conducting module 5, the semiconductor refrigeration sheet 6 and the cold-conducting module 7, ensuring that the components are tightly combined and stably positioned.

[0022] See also Figure 1 and 3 , install the coupling guide block 2 on one side of the hot insulation shell 4 and fix it with screws 3, install the pump shaft guide block 10 on one side of the cold insulation shell 8 and fix it with screws 11, and complete the assembly of the semiconductor hot and cold module. Finally, fix the assembled semiconductor hot and cold module on the lifting platform 23 to ensure that it is firmly installed to provide a stable foundation for subsequent operations.

[0023] See also Figure 1-4 When assembling the shaft parts, first install the coupling 1 on the coupling fixture 17, place the pump shaft 9 on the pump shaft placement block 21, and fix the pump shaft 9 with the pump shaft fixing clamp 19 to ensure the stability of the two in the initial position.

[0024] After pressing the workbench start function key, the electric cylinder 16 drives the coupling fixture 17 and the coupling 1 to advance along the predetermined track, and the coupling 1 is accurately installed into the heating end through the central guide hole of the guide block 2. During this process, the built-in distance sensor of the electric cylinder 16 monitors the advancement distance in real time. When the set value is reached, it indicates that the coupling 1 has been installed in place. Figure 1 and Figure 3 shown.

[0025] At the same time, the screw motor 20 drives the pump shaft support block 21 to move along the guide rail 18, so that the pump shaft 9 is aligned with the center hole of the pump shaft guide block 10. Then the electric cylinder 22 drives the guide rail 18, together with the pump shaft support block 21 and the pump shaft 9, to be installed into the refrigeration end through the center guide hole of the pump shaft guide block 10. The built-in distance sensor of the electric cylinder 22 is also used to determine whether the pump shaft 9 is installed in place.

[0026] After the built-in pressure sensors of the electric cylinder 16 and the electric cylinder 22 confirm that both are installed in place, the DC power supply of the semiconductor cooling plate 6 is started. At this time, the cooling surface of the semiconductor cooling plate 6 quickly cools the installation part of the pump shaft 9 to -20°C through the cooling module 7. According to the thermal expansion coefficient calculation formula, ΔL=α 泵轴 *L*ΔT, the outer diameter of the pump shaft shrinks by 0.007mm, and the outer diameter of the pump shaft shrinks to φ15.993mm; the heating surface quickly heats the inner hole of the coupling 1 to +160℃ through the heat conduction module 5. According to ΔL=α 联轴器 *L*ΔT, the inner diameter of the coupling expands by 0.039mm, and the inner diameter of the coupling expands to φ16.029mm. The pump shaft and the coupling meet the clearance fit requirements, and the clearance is 0.036mm.

[0027] After completing the heating and freezing operations, press the assembly function key, and the electric cylinder 16 and the electric cylinder 22 drive the coupling 1 and the pump shaft 9 to retreat 300mm respectively, and the lifting platform 23 drives the semiconductor hot and cold module to descend to the bottom of the workbench. Then, the electric cylinder 16 drives the coupling 1 to move to the right, inserts the pump shaft 9 into the inner hole of the coupling 1, and waits for about 10 seconds. During this period, the outer diameter of the pump shaft expands rapidly due to the high temperature of the inner hole of the coupling, and conversely, the inner hole of the coupling shrinks rapidly due to the low temperature of the outer diameter of the pump shaft. The gap between the pump shaft and the coupling is rapidly reduced, and the shaft assembly is completed. The staff then removes the shaft assembly and completes the assembly of the shaft assembly. Finally, press the return function key, and the electric cylinder 16 and the electric cylinder 22 drive the coupling 1 and the pump shaft 9 to retreat to the initial position respectively, and the lifting platform 23 drives the semiconductor hot and cold module back to the workbench to prepare for the next assembly operation.

[0028] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A temperature difference assembly device for interference-fit shaft parts of a submersible electric pump, characterized in that: include: Semiconductor cooling and heating module, which has a built-in semiconductor cooling sheet, and the semiconductor cooling sheet has a vacuum cavity insulation structure inside, and generates a heating surface and a cooling surface at both ends through the Peltier effect, thereby realizing cooling and heating functions; A heat conduction module is installed on the heating surface of the semiconductor refrigeration sheet. The heat conduction module is made of a ceramic material with high thermal conductivity and low thermal expansion coefficient, and silicone grease is coated between the heat conduction module and the semiconductor refrigeration sheet for efficient heat transfer. A cooling module is arranged on the cooling surface of the semiconductor cooling sheet. The cooling module is made of a ceramic material with high thermal conductivity and low thermal expansion coefficient, and silicone grease is coated between the module and the semiconductor cooling sheet to efficiently transfer cold. The heat insulation shell is installed on the outside of the heat conduction module to play a role in heat insulation and reduce heat loss; The cold insulation shell is installed outside the cooling module to play a role of heat insulation and reduce the loss of cold. The hot insulation shell and the cold insulation shell are fastened by stopper positioning and fastening components, and at the same time, the heat conduction module, the semiconductor refrigeration sheet and the cooling module are pressed to ensure that the components are tightly combined; A coupling guide block is installed on one side of the heat insulation shell and is used to accurately guide the coupling so that it can be accurately installed into the heating end; The pump shaft guide block is installed on one side of the cold insulation shell and is used to accurately guide the pump shaft so that it can be accurately installed in the refrigeration end.

2. The temperature difference assembly device for interference-fit shaft fittings of a submersible electric pump according to claim 1, characterized in that: It also includes a lifting platform, and the semiconductor hot and cold module is fixed on the lifting platform.

3. A temperature difference assembly method for interference fit shaft parts of a submersible electric pump, characterized in that: The assembly device according to claim 1 or 2 comprises the following steps: (i) Install the coupling on the coupling fixture, place the pump shaft on the pump shaft placement block and fix it with the pump shaft fixing clamp, so that the coupling and pump shaft are in the initial preparation state; (ii) The drive coupling is installed into the heating end through the central guide hole of the coupling guide block, and the drive pump shaft is installed into the cooling end through the central guide hole of the pump shaft guide block, and the installation is confirmed to be in place through monitoring by the distance sensor to ensure the accuracy of assembly; (iii) Start the DC power supply of the semiconductor refrigeration sheet, so that the pump shaft installation part is cooled by the cooling module, and the inner hole of the coupling assembly is heated by the heat conduction module, and the characteristics of the semiconductor refrigeration sheet are used to realize the cold contraction of the pump shaft and the thermal expansion of the coupling; (IV) Drive the coupling and pump shaft back 300mm, lower the semiconductor hot and cold module, move the coupling to insert the pump shaft into its hole, remove the shaft fitting after the shaft fitting is tightly fitted, and complete the assembly process; (V) Return the coupling and pump shaft to their original positions, lift the semiconductor heating and cooling module, and prepare for the next assembly.

4. The temperature difference assembly method of the interference fit shaft of the submersible electric pump according to claim 3 is characterized in that: In the step (iii), the outer diameter of the pump shaft is controlled to shrink and the inner diameter of the coupling is controlled to expand until the outer diameter of the pump shaft is smaller than the inner hole size of the coupling to meet the clearance fit, ensuring that the two can achieve a tight fit.

5. The temperature difference assembly method of the interference fit shaft of the submersible electric pump according to claim 3 is characterized in that: In the step of confirming that the coupling and pump shaft are installed in place, the built-in pressure sensor of the electric cylinder is used to make a judgment to ensure that the assembly is in place.

6. The temperature difference assembly method of the interference fit shaft of the submersible electric pump according to claim 3 is characterized in that: After heating and freezing are completed, the electric cylinder drives the coupling and the pump shaft backward. After the lifting platform drives the semiconductor hot and cold module to descend to the bottom of the workbench, the electric cylinder drives the coupling to move and insert the pump shaft into the inner hole of the coupling to complete the tight fitting of the shaft parts.

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