A surface carburizing treatment device for carbon steel self-tapping screw production

Abstract

The present application relates to the technical field of carburizing treatment, in particular to a surface carburizing treatment equipment for carbon steel self-tapping screw production, comprising: a segmented carburizing treatment mechanism, the segmented carburizing treatment mechanism comprises a treatment box for carburizing treatment, and the treatment box is provided with an electromagnetic heating coil for heating the screw. The tip and the shaft of the screw are soaked in water by using water, and the tip and the shaft are not subjected to carburizing treatment due to the separation of water. The nut is heated by the first electromagnetic heating coil, and then the atmosphere is sprayed out to make the nut subjected to carburizing treatment. After the carburizing treatment of the nut is completed, the water soaked in the shaft is pumped out, and then the shaft is subjected to carburizing treatment. Then the tip is subjected to carburizing treatment in the same way. The different parts of the screw are effectively separated by water soaking, different temperatures and carburizing conditions can be set for each part, so that the performance requirements of different parts can be better met.

Description

Technical Field

[0001] This invention relates to the field of carburizing technology, and more specifically to a surface carburizing treatment device for the production of carbon steel self-tapping screws. Background Technology

[0002] Carbon steel self-tapping screws are a specially designed type of screw, primarily used for joining different materials. These screws feature a self-threading capability; their pointed tip design allows them to cut the corresponding thread as they are screwed into the material, eliminating the need for pre-drilling. This design significantly improves installation efficiency.

[0003] In the processing of carbon steel self-tapping screws, carburizing treatment is required to enhance the surface hardness and wear resistance of the screws. Carburizing is a chemical heat treatment process. Specifically, it involves heating and holding the steel part in a carburizing medium, allowing carbon atoms to penetrate into the surface layer of the steel part, thereby increasing the carbon content of the surface layer and forming a certain carbon concentration gradient. For example, the surface carburizing treatment equipment for the production of carbon steel self-tapping screws, as described in application number CN202210896117.7, is specifically designed for carburizing carbon steel self-tapping screws.

[0004] Most existing carburizing equipment directly heats the carbon steel self-tapping screws as a whole. Heating is a crucial step in carburizing. On one hand, heating increases the diffusion rate of carbon atoms and lowers the activation energy, thus accelerating carbon penetration into the metal surface. On the other hand, heating improves the permeability of the metal, relaxes the crystal structure, and forms a uniform carburized layer. Furthermore, appropriate temperature and time can control the depth and hardness of the carburized layer, improving the material's hardness and strength, thereby achieving the desired carburizing effect.

[0005] However, different parts of a self-tapping screw have different functional requirements. For example, the screw head usually needs to withstand torque and requires high hardness to prevent deformation during tightening, necessitating a heating temperature of 850℃-900℃. The shank, while functioning differently from the head, must support the load applied by the head, so it needs not only sufficient hardness but also a certain degree of flexibility, requiring a heating temperature of 800℃-850℃. The tip often needs a certain degree of toughness to resist bending or tensile forces, requiring a heating temperature of 780℃-840℃. Therefore, different parts of the screw need to be heated to different temperatures. However, existing methods of overall heating and carburizing may lead to uneven performance, deformation, cracking, and insufficient toughness in some areas after carburizing the screw. Summary of the Invention

[0006] To address the aforementioned shortcomings of existing technologies, this invention provides a surface carburizing treatment device for the production of carbon steel self-tapping screws. This device effectively solves the problems that existing integral heating carburizing methods may cause uneven performance, deformation, cracks, and insufficient toughness in self-tapping screws after carburizing.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] This invention provides a surface carburizing treatment device for the production of carbon steel self-tapping screws, comprising:

[0009] The segmented carburizing treatment mechanism includes a treatment chamber for carburizing treatment, in which an electromagnetic heating coil for heating screws is installed. The electromagnetic heating coil is divided into a first electromagnetic heating coil, a second electromagnetic heating coil, and a third electromagnetic heating coil. The first, second, and third electromagnetic heating coils are connected to a power source via an electromagnetic controller. The segmented carburizing treatment mechanism also includes an atmosphere adaptive spraying component for spraying atmosphere onto the screw surface. The atmosphere adaptive spraying component includes a first air pump and a second air pump installed inside the heating chamber for supplying atmosphere. The segmented carburizing treatment mechanism also includes multiple sets of clamping and detection components for fixing and holding screws and detecting screw diameter, and a separating component for separating screws.

[0010] The staged carburizing treatment mechanism includes a partition fixedly connected inside the treatment chamber and a placement plate slidably connected inside the treatment chamber. The partition and placement plate divide the treatment chamber into three carburizing spaces arranged vertically. Each of the three carburizing spaces is equipped with a thermometer and an atmosphere concentration meter. The thermometer, atmosphere concentration meter, electromagnetic heating coil, first air pump, and second air pump are electrically connected to a PLC controller to form the staged treatment mechanism.

[0011] Preferably, the segmented carburizing treatment mechanism further includes two symmetrical electric telescopic rods fixedly connected to the top of the partition plate. The telescopic ends of the electric telescopic rods are fixedly connected to the placement plate. The top of both the placement plate and the partition plate are provided with placement slots of the same size, which are used to place screws.

[0012] Preferably, the lower outer side of the placement slot in the partition is connected to the third electromagnetic heating coil, the upper outer side of the placement slot in the partition is connected to the second electromagnetic heating coil, and the upper outer side of the placement slot in the placement plate is connected to the first electromagnetic heating coil.

[0013] Preferably, the atmosphere adaptive spraying assembly further includes a sealing cover for sealing the treatment box. The bottom end of the sealing cover is fixedly connected to a plurality of exhaust rings, and each exhaust ring corresponds to a placement groove. The bottom end of each exhaust ring is fixedly connected to a first pressurized nozzle arranged in a circumferential array. One of the exhaust rings is fixedly connected to an air inlet pipe. The air inlet end of the air inlet pipe is airtightly inserted into a vent pipe. An atmosphere chamber is fixedly connected to the outer wall of the treatment box. The top end of the atmosphere chamber is fixedly connected to a first suction pump. The exhaust end of the first suction pump is fixedly connected to the vent pipe.

[0014] Preferably, the partition has two vertically arranged first and second exhaust spaces. Multiple second booster nozzles are arranged in a circumferential array around the top of the partition and surrounding each placement slot, and these second booster nozzles are connected to the first exhaust spaces. Multiple third booster nozzles are arranged in a circumferential array on the inner wall of each placement slot in the partition, and these third booster nozzles are connected to the second exhaust spaces. A second suction pump is fixedly connected to the side wall of the atmosphere chamber. The air inlet of the second suction pump is connected to the interior of the atmosphere chamber, and the air outlet of the second suction pump is fixedly connected to a diverter pipe. The diverter pipe is fixedly connected to a first air inlet pipe and a second air inlet pipe, respectively communicating with the first and second exhaust spaces. A first normally closed solenoid valve and a second normally closed solenoid valve are respectively installed in the first and second air inlet pipes. ， Furthermore, the first normally closed solenoid valve and the second normally closed solenoid valve are electrically connected to the PLC controller.

[0015] Preferably, each set of clamping detection components includes multiple sets of clamping rods slidably connected to the bottom end of a partition. One clamping rod has a first toothed plate fixedly connected to both side walls, and the other clamping rod has a second toothed plate fixedly connected to both top ends. The bottom end of the partition is fixedly connected to gears that mesh with the first and second toothed plates respectively. The top end of the partition is fixedly connected to a motor for driving the gears. An infrared transmitter and an infrared receiver are fixedly connected to opposite sides of the two clamping rods respectively. The infrared transmitter and infrared receiver are electrically connected to the PLC controller.

[0016] Preferably, the staged carburizing treatment mechanism further includes an ultrasonic rangefinder fixedly connected to the bottom of the sealing cover, the bottom of the partition is fixedly connected to a thermometer, the top of the partition is fixedly connected to a thermometer, the bottom of the sealing cover is fixedly connected to a thermometer, the side wall of the treatment box is fixedly connected to an atmosphere detection concentration meter, and atmosphere detection concentration meters are installed between the partition and the bottom of the treatment box, between the partition and the placement plate, and between the placement plate and the sealing cover. The atmosphere detection concentration meter, the thermometer, the ultrasonic rangefinder, and the PLC controller are electrically connected.

[0017] Preferably, the partition assembly includes a water-cooled box fixedly connected to the outer wall of the processing box, a semiconductor cooling plate embedded inside the water-cooled box, a first water pump and a second water pump fixedly connected to the side wall of the processing box, the inlet end of the first water pump being connected to the water-cooled box, the outlet end of the first water pump being connected to the interior of the processing box, the inlet end of the second water pump being connected to the interior of the processing box, a water temperature detector being fixedly connected to the lower part of the inner wall of the processing box, the outlet end of the second water pump being connected to the water-cooled box, and the semiconductor cooling plate, the first water pump, the second water pump, the water temperature detector, and the PLC control circuit being electrically connected to form a water-cooling circuit.

[0018] The technical solution provided by this invention has the following advantages compared with the known prior art:

[0019] 1. By first soaking the tip and shaft of the screw in water, the water separation prevents the tip and shaft from being carburized. The nut is then heated by a first electromagnetic heating coil, and an atmosphere is sprayed onto the nut to carburize it. After the nut is carburized, the water is removed from the shaft, and the shaft is then carburized. The tip is then carburized in the same way. The water soaking effectively separates the different parts of the screw, allowing different temperatures and carburizing conditions to be set for each part, thus better meeting the performance requirements of different parts and improving processing efficiency and product quality.

[0020] 2. As the carburizing process proceeds, after the initial stage, with the increase of carbon concentration and the saturation of surface active sites, the carburizing stage will gradually transition to the transition stage. Because the absorption rate of the atmosphere by the screws slows down in the transition stage, the atmosphere in the treatment chamber will slowly accumulate. By detecting the atmosphere concentration in the treatment chamber using an atmosphere concentration meter, it can be determined whether the carburizing process has entered the next stage. When entering the next stage, by reducing the atmosphere entering the treatment chamber, a suitable carbon transport rate can be maintained, ensuring the continuity of the carburizing process and preventing material performance degradation caused by over-carburizing. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0022] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0023] Figure 2 For the present invention Figure 1 Enlarged structural diagram of section B;

[0024] Figure 3 This is a schematic diagram of the internal three-dimensional structure of the present invention. Figure 1 ;

[0025] Figure 4 This is a partial cross-sectional three-dimensional structural schematic diagram of the present invention;

[0026] Figure 5 For the present invention Figure 4 Enlarged structural diagram of section A;

[0027] Figure 6 This is a schematic diagram of the three-dimensional structure of the sealing cap of the present invention;

[0028] Figure 7 This is a schematic diagram of the internal three-dimensional structure of the present invention. Figure 2 ;

[0029] Figure 8 For the present invention Figure 7 Enlarged structural diagram of section C;

[0030] Figure 9 This is a three-dimensional cross-sectional view of the partition of the present invention.

[0031] Reference numerals: 1. Segmented carburizing treatment mechanism; 11. Treatment box; 12. First electromagnetic heating coil; 13. Second electromagnetic heating coil; 14. Third electromagnetic heating coil; 15. Atmosphere adaptive spray assembly; 151. Atmosphere box; 152. Sealing cover; 153. Exhaust ring; 154. First booster nozzle; 155. Inlet pipe; 156. Vent pipe; 157. First vacuum pump; 158. First exhaust space; 159. Second exhaust space; 1510. Second booster nozzle; 1511. Third booster nozzle; 1512. Second vacuum pump; 1513. Diverter pipe; 1514. First air inlet pipe; 151 5. Second air inlet duct; 16. Clamping and detection assembly; 161. Clamping rod; 162. First toothed plate; 163. Second toothed plate; 164. Gear; 165. Motor; 166. Infrared transmitter; 167. Infrared receiver; 17. Separation assembly; 171. Water-cooled box; 172. Semiconductor cooling plate; 173. First water pump; 174. Second water pump; 175. Water temperature detector; 18. Partition plate; 19. Electric telescopic rod; 110. Placement plate; 111. Placement slot; 2. Staged carburizing treatment mechanism; 21. Thermometer; 22. Atmosphere concentration meter; 23. Ultrasonic rangefinder; 3. Screw. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0033] The present invention will be further described below with reference to embodiments.

[0034] Example: Refer to Figures 1 to 9 A surface carburizing treatment device for the production of carbon steel self-tapping screws, comprising:

[0035] The screw 3 can be heated and carburized in stages using the specific structure shown below. (Refer to...) Figures 1 to 9 The segmented carburizing treatment mechanism 1 includes a treatment box 11 for carburizing treatment. The treatment box 11 is equipped with an electromagnetic heating coil for heating the screw 3. The electromagnetic heating coil is divided into a first electromagnetic heating coil 12, a second electromagnetic heating coil 13, and a third electromagnetic heating coil 14. The first electromagnetic heating coil 12, the second electromagnetic heating coil 13, and the third electromagnetic heating coil 14 are connected to the power supply through an electromagnetic controller. The segmented carburizing treatment mechanism 1 also includes an atmosphere adaptive spraying component 15 for spraying atmosphere onto the surface of the screw 3. The atmosphere adaptive spraying component 15 includes a first air pump 157 and a second air pump 1512 for supplying atmosphere inside the heating box. The segmented carburizing treatment mechanism 1 also includes multiple sets of clamping and detection components 16 for fixing and clamping the screw 3 and detecting the diameter of the screw 3, and a separation component 17 for separating the screw 3.

[0036] The segmented carburizing treatment mechanism 1 also includes a partition 18 fixedly connected inside the treatment box 11. Two symmetrical electric telescopic rods 19 are fixedly connected to the top of the partition 18. A placement plate 110 is fixedly connected to the top of the electric telescopic rods 19 and is airtightly slidably connected to the inner wall of the treatment box 11. The top of the placement plate 110 and the partition 18 are both provided with placement grooves 111 of the same size. The placement grooves 111 are used to place screws 3.

[0037] The screw 3 can be segmented using the following specific structure, as shown in the reference. Figures 1 to 3The partition assembly 17 includes a water-cooled box 171 fixedly connected to the outer wall of the processing box 11. A semiconductor cooling plate 172 is embedded inside the water-cooled box 171. A first water pump 173 and a second water pump 174 are fixedly connected to the side wall of the processing box 11. The inlet of the first water pump 173 is connected to the water-cooled box 171, and the outlet of the first water pump 173 is connected to the interior of the processing box 11. The inlet of the second water pump 174 is connected to the interior of the processing box 11. A water temperature detector 175 is fixedly connected to the lower part of the inner wall of the processing box 11. The outlet of the second water pump 174 is connected to the water-cooled box 171. The semiconductor cooling plate 172 and the first water pump 174 are also fixedly connected. 3. The second water pump 174 is electrically connected to the water temperature detector 175 to form a water cooling circuit. After the first water pump 173 is pre-set to inject water from the water cooling box 171 into the treatment box 11, the cooled water is exactly at the same level as the upper surface of the placement plate 110. This is to prevent carbonization of the tip of the screw 3 and the rod body. The second water pump 174 is pre-set to pump water from the treatment box 11 until it is at the same level as the upper surface of the partition plate 18. This is because carbonization is required for the rod body but not for the tip. The first water pump 173 and the second water pump 174 are electrically connected to the PLC controller.

[0038] The screw 3 is heated in sections using the following specific structure, see reference. Figure 3 The lower outer side of the placement slot 111 in the partition 18 is connected to the third electromagnetic heating coil 14, the upper outer side of the placement slot 111 in the partition 18 is connected to the second electromagnetic heating coil 13, and the upper outer side of the placement slot 111 in the placement plate 110 is connected to the first electromagnetic heating coil 12.

[0039] The third electromagnetic heating coil 14 is used to heat the tip of the bottom of the screw 3. Therefore, the diameter of the third electromagnetic heating coil 14 only needs to be larger than the diameter of the placement groove 111. The second electromagnetic heating coil 13 is used to heat the body of the screw 3. Since the diameter of the body is larger than that of the tip, the diameter of the second electromagnetic heating coil 13 is larger than that of the third electromagnetic heating coil 14. The first electromagnetic heating coil 12 is used to heat the nut of the screw 3. Since the diameter of the nut is larger than that of the body, the diameter of the first electromagnetic heating coil 12 is larger than that of the second electromagnetic heating coil 13.

[0040] The screw 3 can be carburized using the following specific structure, see reference. Figure 1 , Figure 2 , Figure 4 , Figure 5 , Figure 6 , Figure 9The atmosphere adaptive spray assembly 15 also includes a sealing cover 152 for sealing the treatment box 11. The bottom end of the sealing cover 152 is fixedly connected to a plurality of exhaust rings 153, and each exhaust ring 153 corresponds to the placement slot 111. The bottom end of the exhaust ring 153 is fixedly connected to a first pressurized nozzle 154 arranged in a circumferential array. One of the exhaust rings 153 is fixedly connected to an air inlet pipe 155. The air inlet end of the air inlet pipe 155 is airtightly inserted into a vent pipe 156. An atmosphere box 151 is fixedly connected to the outer wall of the treatment box 11. A first suction pump 157 is fixedly connected to the top end of the atmosphere box 151. The exhaust end of the first suction pump 157 is fixedly connected to the vent pipe 156. The atmosphere is one or more of carbon dioxide, ammonia, acetylene, and methane.

[0041] The partition 18 has two vertically arranged first exhaust spaces 158 and second exhaust spaces 159. Multiple second booster nozzles 1510 are arranged in a circumferential array around the top of the partition 18 and surrounding each placement slot 111. The second booster nozzles 1510 are connected to the first exhaust spaces 158. Multiple third booster nozzles 1511 are arranged in a circumferential array on the inner wall of the placement slots 111 in the partition 18. The third booster nozzles 1511 are connected to the second exhaust spaces 159. A second suction pump is fixedly connected to the side wall of the atmosphere chamber 151. 1512, the air inlet of the second air pump 1512 is connected to the interior of the atmosphere chamber 151, and the exhaust end of the second air pump 1512 is fixedly connected to a diversion pipe 1513. The diversion pipe 1513 is fixedly connected to a first air inlet pipe 1514 and a second air inlet pipe 1515, which are respectively connected to the first exhaust space 158 and the second exhaust space 159. A first normally closed solenoid valve and a second normally closed solenoid valve are respectively installed in the first air inlet pipe 1514 and the second air inlet pipe 1515, and the first normally closed solenoid valve and the second normally closed solenoid valve are electrically connected to the PLC controller.

[0042] The screw 3 is clamped and its diameter is measured using the following specific structure, as shown in the reference. Figure 7 , Figure 8 Each clamping and detection assembly 16 includes multiple clamping rods 161 slidably connected to the bottom end of a partition 18. One clamping rod 161 has a first toothed plate 162 fixedly connected to both side walls, and the other clamping rod 161 has a second toothed plate 163 fixedly connected to both top ends. The bottom end of the partition 18 is fixedly connected to gears 164 that mesh with the first toothed plate 162 and the second toothed plate 163 respectively. The top end of the partition 18 is fixedly connected to a motor 165 for driving the gears 164. An infrared transmitter 166 and an infrared receiver 167 are fixedly connected to opposite sides of the two clamping rods 161 respectively. The infrared transmitter 166 and the infrared receiver 167 are electrically connected to the PLC controller.

[0043] The screw 3 is subjected to staged carburizing treatment using the following specific structure, as referred to... Figure 6 The staged carburizing treatment mechanism 2 includes a partition 18 fixedly connected inside the treatment box 11 and a placement plate 110 slidably connected inside the treatment box 11. The partition 18 and the placement plate 110 divide the treatment box 11 into three carburizing spaces arranged vertically. Each of the three carburizing spaces is equipped with a thermometer 21 and an atmosphere concentration meter 22. The thermometer 21, the atmosphere concentration meter 22, the electromagnetic heating coil, the first vacuum pump 157, and the second vacuum pump 1512 are electrically connected to the PLC controller to form a staged treatment mechanism. The three carburizing spaces are arranged from top to bottom as follows: the top of the treatment box 11 and the placement plate 110 form the first carburizing space; the partition 18 and the placement plate 110 form the second carburizing space; and the partition 18 and the bottom of the treatment box form the third carburizing space.

[0044] The staged carburizing treatment mechanism 2 also includes an ultrasonic rangefinder 23 fixedly connected to the bottom of the sealing cover 152, a thermometer 21 fixedly connected to the bottom of the partition 18 and the thermometer 21 fixedly connected to the top of the partition 18, a thermometer 21 fixedly connected to the bottom of the sealing cover 152, an atmosphere detection concentration meter 22 fixedly connected to the side wall of the treatment box 11, and an atmosphere detection concentration meter 22 is installed between the partition 18 and the bottom of the treatment box 11, between the partition 18 and the placement plate 110, and between the placement plate 110 and the sealing cover 152. The atmosphere detection concentration meter 22, the thermometer 21, the ultrasonic rangefinder 23 are electrically connected to the PLC controller.

[0045] The working principle of this invention is as follows:

[0046] First, place the screw 3 in the placement slot 111, then place the sealing cap 152 on the processing box 11. At the same time, the air inlet pipe 155 and the vent pipe 156 need to be connected. Then, use external sealing technology, such as applying wax to the connection between the sealing cap 152 and the processing box 11 to further seal.

[0047] Then, screw 3 is heated and then carburized. The specific process is as follows:

[0048] The electric telescopic rod 19 is started by the PLC controller, which drives the placement plate 110 to move downward. The screw 3 will descend synchronously by its own gravity. The descent distance can be known by the real-time monitoring of the nut height by the ultrasonic rangefinder 23. When the nut height is detected to be stationary (so that the lower surface of the nut does not contact the placement plate 110 and does not affect the carburizing treatment of the nut), it means that the bottom of the screw 3 has touched the bottom. Then the electric telescopic rod 19 is stopped by the PLC controller.

[0049] Then, by controlling the first water pump 173, the uncooled water in the water-cooled box 171 is discharged into the treatment box 11, so that the water submerges the tip of the screw 3 and the rod body, preventing it from being carburized.

[0050] The PLC controller then starts the motor 165, which drives the gear 164 to rotate. The gear 164 then drives the first toothed plate 162 and the second toothed plate 163 to move in the direction of the gear 164, thereby driving the clamping rod 161 to clamp the screw 3. The diameter of the screw 3 can be determined by the infrared transmitter 166, the infrared receiver 167 and the data processing module in the PLC controller. The screw 3 model can be determined by the diameter of the screw 3 (the diameter corresponding to different screw types is set in the PLC controller in advance).

[0051] Then, the PLC controller controls the current supplied to the first electromagnetic heating coil 12 according to the type of screw, so that the nut is heated to 850℃-900℃. When the temperature of the nut is detected by the thermometer 21 to reach 850℃-900℃, the first electromagnetic heating coil 12 is controlled to heat the nut with low power, so that the nut is kept at 850℃-900℃.

[0052] Then, by controlling the first air pump 157, an atmosphere is provided to the air inlet pipe 155, and then sprayed onto the rod body and the nut respectively through the first booster nozzle 154, so that the nut is carburized. The power of the first air pump 157 is adaptively adjusted by the PLC controller according to the size of the nut.

[0053] The carburizing process for screws typically involves four stages: initial stage, transition stage, stabilization stage, and post-cooling treatment stage. Each stage has distinct characteristics, as detailed below: Initial Stage: In the initial stage of carburizing, due to the high temperature and atmosphere concentration, the adsorption rate of carbon on the screw is high, and the adsorption amount increases rapidly (rapid adsorption). Transition Stage: As time progresses, the concentration of the atmosphere on the screw surface begins to increase, and the adsorption rate gradually slows down. Although carbon continues to be adsorbed, the adsorption effect begins to decline significantly due to the reduction in available active sites (slower adsorption rate). Stabilization Stage: In this stage, a dynamic equilibrium is reached between adsorption and diffusion. The atmosphere concentration is relatively stable on the screw surface and inside the screw. Although adsorption and dissolution still occur during this process, the adsorbed carbon may penetrate more into the metal interior rather than continue to be adsorbed on the surface (dynamic equilibrium).

[0054] In this case, the amount of air discharged into the treatment chamber 11 by the first air pump 157 in the initial stage is x L / min, the amount of air discharged into the treatment chamber 11 in the transition stage is y L / min, and the amount of air discharged into the treatment chamber 11 in the stable stage is z L / min.

[0055] The concentration of the atmosphere is monitored in real time by the atmosphere concentration meter 22. Since carburizing is a continuous process, the atmosphere is supplied to the treatment chamber 11 for a long time. In the initial stage of carburizing, the adsorption rate of the atmosphere is relatively fast, so the amount of atmosphere discharged into the treatment chamber 11 by the first vacuum pump 157 at xL / min will be consumed quickly. However, as time goes by, it will slowly enter the transition stage. In this stage, the adsorption rate slows down, but the atmosphere is still supplied at the initial stage, which will cause the atmosphere to accumulate in the treatment chamber 11. When the atmosphere concentration meter 22 detects an increase in the amount of atmosphere, it means that the carburizing process has entered the transition stage. Therefore, the PLC controller needs to control the amount of atmosphere discharged into the treatment chamber 11 by the first vacuum pump 157 at yL / min to prevent excessive accumulation in the treatment chamber 11. As the carburizing process proceeds, the carburizing process will slowly enter the stable stage and reach dynamic equilibrium. Therefore, the process will slow down further in this stage. The PLC controller needs to further control the first vacuum pump 157 to discharge the atmosphere into the treatment chamber 11 at yL / min for carburizing.

[0056] Based on the pre-tested carburizing time of screw 3 and nut, when the time is about to be reached, the second water pump 174 is started by controlling the PLC controller to extract the water in the treatment tank 11 for the first time, and then the extracted water is cooled by the semiconductor cooling plate 172 for subsequent use.

[0057] Then, the heat is transferred to the shaft through the heat conduction of screw 3 to preheat the shaft and dry the water in the shaft. When the carburizing treatment of the screw 3 nut reaches the preset time, the PLC controller controls the second electromagnetic heating coil 13 to be energized, the first electromagnetic heating coil 12 to be de-energized, the first air pump 157 to stop working and the second air pump 1512 to be started. At the same time, the first normally closed solenoid valve is opened, so that the atmosphere is sprayed onto the shaft through the second pressurized nozzle 1510 to perform carburizing treatment on the shaft. The remaining steps are the same as the carburizing treatment of the nut.

[0058] After the carburizing of the rod body is completed, the second water pump 174 is started by controlling the PLC controller to extract the water in the treatment tank 11 for the second time, so that the tip of the screw 3 is exposed. Then, the first normally closed solenoid valve is closed and the second normally closed solenoid valve is opened by controlling the PLC controller, so that the atmosphere is sprayed onto the rod body through the third pressurized nozzle 1511 to perform carburizing treatment on the tip. The carburizing treatment of the tip is the same as the carburizing treatment of the nut.

[0059] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the protection scope of the technical solutions of the embodiments of the present invention.

Claims

1. A surface carburizing treatment device for the production of carbon steel self-tapping screws, characterized in that, include: The segmented carburizing treatment mechanism (1) includes a treatment box (11) for carburizing treatment. The treatment box (11) is provided with an electromagnetic heating coil for heating the screw (3). The electromagnetic heating coil is divided into a first electromagnetic heating coil (12), a second electromagnetic heating coil (13), and a third electromagnetic heating coil (14). The first electromagnetic heating coil (12), the second electromagnetic heating coil (13), and the third electromagnetic heating coil (14) are connected to the power supply through an electromagnetic controller. The segmented carburizing treatment mechanism (1) also includes an atmosphere adaptive spraying component (15) for spraying atmosphere onto the surface of the screw (3). The atmosphere adaptive spraying component (15) includes a first air pump (157) and a second air pump (1512) for supplying atmosphere inside the heating box. The segmented carburizing treatment mechanism (1) also includes multiple sets of clamping and detection components (16) for fixing and clamping the screw (3) and detecting the diameter of the screw (3), and a separation component (17) for separating the screw (3). The atmosphere adaptive ejection assembly (15) also includes a sealing cover (152) for sealing the treatment box (11). The bottom end of the sealing cover (152) is fixedly connected to a plurality of exhaust rings (153), and each exhaust ring (153) corresponds to the placement groove (111). The bottom end of the exhaust ring (153) is fixedly connected to a first pressurized nozzle (154) arranged in a circumferential array, and one of the exhaust rings (153) is fixedly connected to an air inlet pipe (155). Each clamping detection assembly (16) includes multiple clamping rods (161) slidably connected to the bottom end of the partition (18). One clamping rod (161) has a first toothed plate (162) fixedly connected to both side walls at both ends, and the other clamping rod (161) has a second toothed plate (163) fixedly connected to both top ends. The bottom end of the partition (18) is fixedly connected to gears (164) that mesh with the first toothed plate (162) and the second toothed plate (163) respectively. The staged carburizing treatment mechanism (2) includes a partition (18) fixedly connected inside the treatment box (11) and a placement plate (110) slidably connected inside the treatment box (11). The partition (18) and the placement plate (110) divide the treatment box (11) into three carburizing spaces arranged vertically. Each of the three carburizing spaces is equipped with a thermometer (21) and an atmosphere concentration meter (22). The thermometer (21), the atmosphere concentration meter (22), the electromagnetic heating coil, the first air pump (157), and the second air pump (1512) are electrically connected to the PLC controller to form a staged treatment mechanism. The segmented carburizing treatment mechanism (1) also includes two symmetrical electric telescopic rods (19) fixedly connected to the top of the partition (18). The telescopic ends of the electric telescopic rods (19) are fixedly connected to the placement plate (110). The top of the placement plate (110) and the partition (18) are both provided with placement slots (111) of the same size. The placement slots (111) are used to place screws (3). The lower outer side of the placement slot (111) in the partition (18) is connected to the third electromagnetic heating coil (14), the upper outer side of the placement slot (111) in the partition (18) is connected to the second electromagnetic heating coil (13), and the upper outer side of the placement slot (111) in the placement plate (110) is connected to the first electromagnetic heating coil (12). The partition (18) has two vertically arranged first exhaust spaces (158) and second exhaust spaces (159). Multiple second booster nozzles (1510) are arranged in a circumferential array around the top of the partition (18) and around each placement slot (111). The second booster nozzles (1510) are connected to the first exhaust spaces (158). Multiple third booster nozzles (1511) are arranged in a circumferential array on the inner wall of the placement slot (111) in the partition (18). The third booster nozzles (1511) are connected to the second exhaust spaces (159).

2. The surface carburizing treatment equipment for the production of carbon steel self-tapping screws according to claim 1, characterized in that, The air inlet end of the air inlet pipe (155) is airtightly connected to a vent pipe (156). An atmosphere chamber (151) is fixedly connected to the outer wall of the processing box (11). A first suction pump (157) is fixedly connected to the top of the atmosphere chamber (151). The exhaust end of the first suction pump (157) is fixedly connected to the vent pipe (156).

3. The surface carburizing treatment equipment for the production of carbon steel self-tapping screws according to claim 2, characterized in that, The atmosphere chamber (151) is fixedly connected to a second air pump (1512) on its side wall. The air inlet of the second air pump (1512) is connected to the interior of the atmosphere chamber (151). The exhaust end of the second air pump (1512) is fixedly connected to a diversion pipe (1513). The diversion pipe (1513) is fixedly connected to a first air inlet pipe (1514) and a second air inlet pipe (1515) that are respectively connected to the first exhaust space (158) and the second exhaust space (159). The first air inlet pipe (1514) and the second air inlet pipe (1515) are respectively equipped with a first normally closed solenoid valve and a second normally closed solenoid valve. The first normally closed solenoid valve and the second normally closed solenoid valve are electrically connected to the PLC controller.

4. The surface carburizing treatment equipment for the production of carbon steel self-tapping screws according to claim 1, characterized in that, The top of the partition (18) is fixedly connected to a motor (165) for driving the gear (164), and an infrared transmitter (166) and an infrared receiver (167) are fixedly connected to opposite sides of the two clamping rods (161), respectively. The infrared transmitter (166) and the infrared receiver (167) are electrically connected to the PLC controller.

5. A surface carburizing treatment device for the production of carbon steel self-tapping screws according to claim 4, characterized in that, The staged carburizing treatment mechanism (2) also includes an ultrasonic rangefinder (23) fixedly connected to the bottom of the sealing cover (152), the bottom of the partition (18) is fixedly connected to the thermometer (21), the top of the partition (18) is fixedly connected to the thermometer (21), the bottom of the sealing cover (152) is fixedly connected to the thermometer (21), the side wall of the treatment box (11) is fixedly connected to the atmosphere detection concentration meter (22), and atmosphere detection concentration meters (22) are installed between the partition (18) and the bottom of the treatment box (11), between the partition (18) and the placement plate (110), and between the placement plate (110) and the sealing cover (152). The atmosphere detection concentration meter (22), the thermometer (21), the ultrasonic rangefinder (23) are electrically connected to the PLC controller.

6. The surface carburizing treatment equipment for the production of carbon steel self-tapping screws according to claim 1, characterized in that, The partition assembly (17) includes a water-cooled box (171) fixedly connected to the outer wall of the processing box (11). A semiconductor cooling plate (172) is embedded in the water-cooled box (171). A first water pump (173) and a second water pump (174) are fixedly connected to the side wall of the processing box (11). The inlet end of the first water pump (173) is connected to the water-cooled box (171), and the outlet end of the first water pump (173) is connected to the interior of the processing box (11). The inlet of the second water pump (174) is connected to the interior of the treatment tank (11). A water temperature detector (175) is fixedly connected to the lower part of the inner wall of the treatment tank (11). The outlet of the second water pump (174) is connected to the water cooling box (171). The semiconductor cooling plate (172), the first water pump (173), the second water pump (174), the water temperature detector (175), and the PLC control circuit are electrically connected to form a water cooling circuit.

Images