Electromagnetic tin pump

Abstract

The application discloses an electromagnetic tin pump, which comprises a pump body, wherein the outer wall of the pump body is sleeved with a magnetic yoke plate, a flow channel for flowing liquid metal is arranged in the pump body, and the flow channel is arranged in the pump body in a vertical extension mode; a magnetic field generating assembly is arranged for generating a magnetic field, the magnetic field generating assembly comprises N-pole magnetic steel and S-pole magnetic steel, and the N-pole magnetic steel and the S-pole magnetic steel are arranged on the front and back sides outside the flow channel respectively; and an electrode is arranged for electrifying the liquid metal, the electrode comprises a positive electrode and a negative electrode, the positive electrode and the negative electrode are arranged on the left and right sides of the flow channel respectively, and part of the positive electrode and the negative electrode is exposed outside the pump body. The electromagnetic tin pump has the advantages that under the interaction of the magnetic field formed by the N-pole magnetic steel and the S-pole magnetic steel and the current flowing between the positive electrode and the negative electrode, the liquid metal can flow from the bottom to the top in the flow channel, and the liquid metal can be used for welding a circuit board at a wave crest.

Description

Technical Field

[0001] This utility model relates to the field of electronic processing industrial equipment technology, and in particular to an electromagnetic tin pump. Background Technology

[0002] With the widespread use of electronic devices, the production volume of circuit boards, as a major component, is constantly increasing. During circuit board production, it is necessary to solder the electronic components on the circuit boards. Currently, selective wave soldering is commonly used to solder circuit boards. This involves an electromagnetic pump utilizing the interaction of a magnetic field and an electric current to create a pressure gradient in liquid metal (such as tin, sodium, potassium, etc.) under electromagnetic force, thereby driving the liquid metal to flow. The wave crest of the liquid metal flow directly contacts the soldering surface of the circuit board to solder it. Based on the driving principle, electromagnetic pumps can be divided into conductive electromagnetic pumps and inductive electromagnetic pumps.

[0003] Existing induction electromagnetic pumps, such as the Chinese invention application "An Integrated Permanent Magnet Type Liquid Metal Electromagnetic Pump" with patent number CN202010995831.2 (authorization announcement number CN112260513A), involve a rotating magnetic field formed between the stator yoke and the rotor permanent magnet when three-phase alternating current is applied to the three-phase winding coil. The rotor permanent magnet is subjected to magnetic force in the rotating magnetic field, causing the rotor to rotate with the rotating magnetic field. The radial magnetic field formed between the rotating rotor permanent magnet and the external yoke in the flow channel will rotate, thereby generating induced eddy currents in the liquid metal in the flow channel. Under the combined action of these eddy currents and the magnetic field formed between the rotor permanent magnet and the external yoke, the liquid metal generates an Ampere force, which in turn drives the liquid metal to flow.

[0004] While the aforementioned induction electromagnetic pump can drive the flow of liquid metal, its components, including a stator yoke, three-phase winding coils, rotor permanent magnet, rotor shaft, and external yoke, make it large, complex, and costly. Furthermore, the large size of existing induction electromagnetic pumps necessitates a large furnace, resulting in a higher flow rate due to the larger volume of liquid metal required. However, factories sometimes receive small-batch orders requiring less liquid metal for circuit board soldering. Using the aforementioned electromagnetic pump and furnace for circuit board soldering would leave a large amount of liquid metal unused in the furnace, leading to waste and increased production costs. Currently, compared to induction electromagnetic pumps, conductive electromagnetic pumps are smaller, have lower flow rates, and are more efficient, making them more suitable for small-batch circuit board soldering orders. Therefore, further improvements are being made to electromagnetic solder pumps. Summary of the Invention

[0005] The technical problem to be solved by this utility model is to provide an electromagnetic solder pump that is simple and reasonable in structure, small in size and low in cost, and capable of soldering circuit boards, in light of the above-mentioned existing technology.

[0006] The technical solution adopted by this utility model to solve the above-mentioned technical problems is as follows: the electromagnetic tin pump includes a pump body, characterized in that: a magnetic yoke plate is sleeved on the outer wall of the pump body, and a magnetic yoke plate is provided inside the pump body.

[0007] A flow channel for supplying liquid metal flow is provided in the pump body, extending vertically.

[0008] A magnetic field generating component is used to generate a magnetic field. The magnetic field generating component includes an N-pole magnet and an S-pole magnet, which are respectively disposed on the front and rear sides of the outside of the flow channel.

[0009] An electrode is used to energize liquid metal. The electrode includes a positive electrode and a negative electrode, which are respectively disposed on the left and right sides of the flow channel, and a portion of the positive electrode and the negative electrode are exposed outside the pump body.

[0010] Furthermore, both the positive and negative electrodes have horizontal and vertical sections. The vertical sections of the positive and negative electrodes are installed inside the pump body, while the horizontal sections of the positive and negative electrodes are exposed on the left and right sides of the pump body for energizing.

[0011] Furthermore, a first fixing hole is provided on the horizontal section of the positive electrode, and a second fixing hole is provided on the horizontal section of the negative electrode. The first and second fixing holes are symmetrically arranged and are connected to the furnace mounting base by means of ceramic gaskets. This electromagnetic solder pump is a semi-submersible type, placed in the furnace used to store molten solder, allowing the molten solder to overflow the N-pole and S-pole magnets. The horizontal sections of the positive and negative electrodes are located above the molten solder. The electromagnetic solder pump is mounted on the furnace through the horizontal sections of the positive and negative electrodes. The furnace mounting base is provided with ceramic gaskets to insulate the positive and negative electrodes from the furnace, preventing short circuits in the connection between the electromagnetic solder pump and the furnace.

[0012] Furthermore, the horizontal segment of the positive electrode is provided with a first wiring hole, and the horizontal segment of the negative electrode is provided with a second wiring hole. The first and second wiring holes are located at the end of the horizontal segment away from the vertical segment. There can be two first and two second wiring holes, thereby making the connection between the wire and the positive and negative electrodes more secure and the current conduction effect more stable.

[0013] Furthermore, the pump body is provided with multiple fixing holes, and the magnetic yoke plate is provided with connecting holes corresponding to the fixing holes. Bolts pass through the fixing holes and connecting holes and are then screwed into nuts to fix the pump body to the magnetic yoke plate. Fixing the pump body to the magnetic yoke plate with bolts and nuts makes the installation of the electromagnetic tin pump more secure.

[0014] Furthermore, the pump body includes two housings made of insulating material, which are mounted opposite each other to form the pump body, with the positive and negative electrodes disposed between the two housings. The insulating material, such as ceramic, can be used to make the housings, and the two housings have identical structures, allowing the pump body to be formed simply by mounting them opposite each other.

[0015] Furthermore, the housing is provided with mounting grooves for mounting the N-pole magnet and the S-pole magnet. These mounting grooves are located on the back side of the groove described below, allowing the N-pole magnet and the S-pole magnet to be respectively positioned on the front and rear sides of the flow channel.

[0016] Furthermore, the shell has grooves on opposite sides for the flow of liquid metal, and two opposite grooves fit together to form a flow channel. These grooves create a vertical flow channel for the liquid metal.

[0017] Furthermore, the groove is streamlined, wider at the bottom and narrower at the top. This streamlined shape allows the liquid metal to flow upwards more smoothly.

[0018] Furthermore, positioning posts are provided on the left and right sides of the groove, and the positive electrode has a first positioning hole for the corresponding positioning post to be inserted, while the negative electrode has a second positioning hole for the corresponding positioning post to be inserted. The positive electrode is installed between the two housings through the cooperation of the first positioning hole and the corresponding positioning post, and the negative electrode is installed between the two housings through the cooperation of the second positioning hole and the corresponding positioning post. The positive and negative electrodes can not only be installed between the two housings, but also on the left and right sides of the flow channel.

[0019] Compared with the prior art, the advantages of this utility model are:

[0020] 1. The magnetic field of this electromagnetic solder pump is set from the N-pole magnet and the S-pole magnet, i.e., along the front-to-back direction. The N-pole magnet and the S-pole magnet are permanent magnets. When a direct current is passed through the positive electrode and the negative electrode, the current direction of this electromagnetic solder pump is from the positive electrode to the negative electrode, i.e., along the left-to-right direction. According to the left-hand rule, the liquid metal can flow from bottom to top in the flow channel. That is, the molten solder flows into the pump body from the lower end of the flow channel. The molten solder is subjected to an upward Ampere force, causing the molten solder to flow out from the upper end of the flow channel. The flowing molten solder can be used to solder circuit boards at the crest of the wave. Therefore, compared with the existing electromagnetic pumps, this electromagnetic solder pump has a simpler and more reasonable structure, fewer components, smaller size, lower weight, and lower production cost. Thus, this electromagnetic solder pump can be adapted to smaller furnaces and is suitable for small-batch orders.

[0021] 2. This electromagnetic solder pump can adjust the flow pressure of the molten solder by adjusting the current. That is, the height of the molten solder wave can be adjusted by using the Ampere force formula, so as to improve the soldering effect of the circuit board.

[0022] 3. The electromagnetic tin pump body is fitted with a magnetic yoke plate. The magnetic yoke plate can concentrate the magnetic field generated by the N pole magnet and the S pole magnet, thus preventing the electromagnetic tin pump from leaking magnetic field. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of an embodiment of the present utility model;

[0024] Figure 2 This is a cross-sectional view of an embodiment of the present utility model;

[0025] Figure 3 This is a cross-sectional view of an embodiment of the present invention from another perspective;

[0026] Figure 4 This is an exploded view of the pump body, N-pole magnet, S-pole magnet, and yoke plate in an embodiment of this utility model.

[0027] Figure 5 This is a schematic diagram of the shell structure in an embodiment of the present utility model;

[0028] Figure 6 This is a schematic diagram illustrating the working principle of an embodiment of the present utility model. Detailed Implementation

[0029] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0030] like Figures 1-6 The figure shown is the preferred embodiment of this utility model.

[0031] like Figures 1-3As shown, the electromagnetic tin pump of this embodiment includes a pump body 1. In this embodiment, the pump body 1 is a high-temperature resistant ceramic component. The pump body 1 is provided with a flow channel 11 for the flow of liquid metal (i.e., molten tin). The flow channel 11 extends vertically and is arranged inside the pump body 1. The pump body 1 is provided with a magnetic field generating component for generating a magnetic field. The magnetic field generating component includes an N-pole magnet 3 and an S-pole magnet 4. The N-pole magnet 3 and the S-pole magnet 4 are permanent magnets. The N-pole magnet 3 and the S-pole magnet 4 are respectively arranged on the front and rear sides outside the flow channel 11. The electromagnetic tin pump of this embodiment needs to be placed in a furnace storing molten tin. Since the pump body 1, the N-pole magnet 3 and the S-pole magnet 4 in the prior art all have good high-temperature resistance, the electromagnetic tin pump can also ensure the magnetic field strength under the high temperature conditions of the furnace. In this embodiment, the pump body 1 is also provided with electrodes for energizing the liquid metal (molten solder). The electrodes include a positive electrode 5 and a negative electrode 6, which are respectively disposed on the left and right sides of the flow channel 11, and part of the positive electrode 5 and the negative electrode 6 are exposed outside the pump body 1. Therefore, the magnetic field direction of this electromagnetic solder pump is from the N pole magnet 3 and the S pole magnet 4, that is, it is arranged in the front-back direction. When a direct current is passed through the positive electrode 5 and the negative electrode 6, the current direction of this electromagnetic solder pump is from the positive electrode 5 to the negative electrode 6, that is, it flows in the left-right direction. According to the left-hand rule, the liquid metal can flow from bottom to top in the flow channel, that is, the molten solder flows into the pump body from the lower end of the flow channel. The molten solder is subjected to an upward Ampere force, causing the molten solder to flow out from the upper end of the flow channel. The flowing molten solder can be used to solder circuit boards at the crest of the wave. In this embodiment, the magnitude of the Ampere force on the liquid metal (molten tin) can be adjusted by the magnetic field strength and current intensity. For example, an adjustable DC constant current power supply of 0-150A can be used to energize the positive electrode 5 and the negative electrode 6. The magnetic induction intensity at the center point between the N pole magnet 3 and the S pole magnet 4 reaches more than 4000 Gauss. Adjusting the current can adjust the height of the molten tin. Furthermore, by applying DC current to the positive electrode 5 and the negative electrode 6, the DC constant current power supply can ensure the stability of the current, thereby ensuring the stability of the molten tin flow.

[0032] Specifically, such as Figure 4 and Figure 5As shown, the pump body 1 in this embodiment is formed by two housings 13 made of insulating material (ceramic) mounted opposite each other. A groove 15 for the flow of liquid metal (i.e., molten tin) is provided on the opposite side of the housing 13. The two opposing grooves 15 together form a flow channel 11. The grooves 15 are streamlined, wider at the bottom and narrower at the top, allowing the molten tin to flow upwards more smoothly. A flow-blocking strip is provided in the middle of the bottom of the groove 15. Due to the resistance of the liquid metal (molten tin), the current is greatest where the contact area between the liquid metal (molten tin) and the positive electrode 5 and the negative electrode 6 is largest and closest. The flow-blocking strip of this application can concentrate the current between the N-pole magnet 3 and the S-pole magnet 4, thereby reducing current loss. The housing 13 has a mounting groove 14 on the back of the groove 15 for mounting the N-pole magnet 3 or the S-pole magnet 4, so that the N-pole magnet 3 or the S-pole magnet 4 are respectively positioned on the front and rear sides outside the flow channel 11. In this embodiment, the positive electrode 5 and the negative electrode 6 are disposed between the two housings 13. Both the positive electrode 5 and the negative electrode 6 are L-shaped plates, each having a horizontal section and a vertical section. The vertical sections of the positive electrode 5 and the negative electrode 6 are installed inside the pump body 1, while the horizontal sections of the positive electrode 5 and the negative electrode 6 are exposed on the left and right sides of the pump body 1. That is, positioning posts 16 are respectively provided on the left and right sides of the groove 15. The vertical section of the positive electrode 5 is provided with a first positioning hole 53 for the corresponding positioning post 16 to be inserted, and the vertical section of the negative electrode 6 is provided with a second positioning hole 63 for the corresponding positioning post 16 to be inserted. The positive electrode 5 is installed between the two housings 13 through the cooperation of the first positioning hole 53 and the corresponding positioning post 16, and the negative electrode 6 is installed between the two housings 13 through the cooperation of the second positioning hole 63 and the corresponding positioning post 16, thereby placing the positive electrode 5 and the negative electrode 6 on the left and right sides of the flow channel 11 respectively. In addition, in this embodiment, the horizontal section of the positive electrode 5 is provided with a first fixing hole 51, and the horizontal section of the negative electrode 6 is provided with a second fixing hole 61. The first fixing hole 51 and the second fixing hole 61 are symmetrically arranged. The first fixing hole 51 and the second fixing hole 61 are connected to the mounting base of the furnace (not shown in the figure) by means of a ceramic gasket (not shown in the figure), so that the electromagnetic solder pump can be placed semi-submerged in the furnace, that is, the molten solder can overflow the N pole magnet 3 and the S pole magnet 4, and the horizontal sections of the positive electrode 5 and the negative electrode 6 are located above the molten solder. Furthermore, in this embodiment, the horizontal section of the positive electrode 5 is provided with two first wiring holes 52, and the horizontal section of the negative electrode 6 is provided with two second wiring holes 62. The first wiring holes 52 and the second wiring holes 62 are located at the end of the horizontal section away from the vertical section. The two first wiring holes 52 and the two second wiring holes 62 make the connection between the wire and the positive electrode 5 and the negative electrode 6 more secure, and make the power supply effect more stable.

[0033] In addition, the outer wall of the pump body 1 in this embodiment is fitted with a magnetic yoke plate 2. The magnetic yoke plate 2 is made of a ferromagnetic material with high magnetic permeability. The magnetic yoke plate 2 can concentrate the magnetic field generated by the N pole magnet 3 and the S pole magnet 4, and prevent the electromagnetic tin pump from leaking magnetic field. That is, the pump body 1 is provided with multiple fixing holes 12, and the magnetic yoke plate 2 is provided with connecting holes 21 corresponding to the fixing holes 12. The bolt passes through the fixing holes 12 and the connecting holes 21 and is screwed with the nut to fix the pump body 1 and the magnetic yoke plate 2.

[0034] The workflow of this embodiment is as follows: First, the electromagnetic solder pump is placed in a furnace for storing molten solder. It engages with the furnace mounting base via the first fixing hole 51 on the positive electrode 5 and the second fixing hole 61 on the negative electrode 6. The first fixing hole 51 and the second fixing hole 61 are connected to the furnace mounting base using ceramic gaskets, allowing the electromagnetic solder pump to be semi-submerged in the molten solder, meaning the molten solder can overflow the N-pole magnet 3 and the S-pole magnet 4, with the horizontal sections of the positive electrode 5 and the negative electrode 6 above the molten solder. Then, wires are connected to the first wiring hole 52 of the positive electrode 5 and the second wiring hole 62 of the negative electrode 6, and a direct current is applied to the positive electrode 5 and the negative electrode 6. Under the influence of the magnetic field formed by the N-pole magnet 3 and the S-pole magnet 4 and the current flowing through the positive electrode 5 and the negative electrode 6, the molten solder flows upwards within the flow channel 11 according to the left-hand rule. Finally, the circuit board to be soldered is placed above the electromagnetic solder pump, ensuring that the molten solder flowing out through the flow channel 11 contacts the circuit board at the crest. Figure 6 As shown, this completes the soldering of the circuit board.

Claims

1. An electromagnetic tin pump, comprising a pump body (1), characterized in that: The outer wall of the pump body (1) is fitted with a magnetic yoke plate (2), and the pump body (1) is equipped with a magnetic yoke plate (2). A flow channel (11) is provided for the flow of liquid metal, and the flow channel (11) extends vertically within the pump body (1); A magnetic field generating component is used to generate a magnetic field. The magnetic field generating component includes an N-pole magnet (3) and an S-pole magnet (4). The N-pole magnet (3) and the S-pole magnet (4) are respectively disposed on the front and rear sides of the outside of the flow channel (11). An electrode is used to energize liquid metal. The electrode includes a positive electrode (5) and a negative electrode (6). The positive electrode (5) and the negative electrode (6) are respectively disposed on the left and right sides of the flow channel (11), and parts of the positive electrode (5) and the negative electrode (6) are exposed outside the pump body (1). The positive electrode (5) and the negative electrode (6) each have a horizontal section and a vertical section. The vertical section of the positive electrode (5) and the negative electrode (6) is installed inside the pump body (1), and the horizontal section of the positive electrode (5) and the negative electrode (6) is exposed on the left and right sides of the pump body (1). The positive electrode (5) has a horizontal section and a vertical section. A first fixing hole (51) is provided on the horizontal section, and a second fixing hole (61) is provided on the horizontal section of the negative electrode (6). The first fixing hole (51) and the second fixing hole (61) are symmetrically arranged. The first fixing hole (51) and the second fixing hole (61) are connected to the furnace mounting base by means of a ceramic gasket. A first wiring hole (52) is provided on the horizontal section of the positive electrode (5), and a second wiring hole (62) is provided on the horizontal section of the negative electrode (6). The first wiring hole (52) and the second wiring hole (62) are located at the end of the horizontal section away from the vertical section.

2. The electromagnetic tin pump according to claim 1, characterized in that: The pump body (1) is provided with a plurality of fixing holes (12), and the magnetic yoke plate (2) is provided with connecting holes (21) corresponding to the fixing holes (12). The bolt passes through the fixing holes (12) and the connecting holes (21) and is then screwed with the nut to fix the pump body (1) and the magnetic yoke plate (2).

3. The electromagnetic tin pump according to claim 1 or 2, characterized in that: The pump body (1) includes two housings (13) made of insulating material, which are mounted opposite each other to form the pump body (1), and the positive electrode (5) and negative electrode (6) are disposed between the two housings (13).

4. The electromagnetic tin pump according to claim 3, characterized in that: The housing (13) is provided with mounting slots (14) for mounting N-pole magnets (3) and S-pole magnets (4).

5. The electromagnetic tin pump according to claim 3, characterized in that: The shell (13) has a groove (15) on one side for the flow of liquid metal, and the two opposite grooves (15) are joined together to form a flow channel (11).

6. The electromagnetic tin pump according to claim 5, characterized in that: The groove (15) has a streamlined shape that is larger at the bottom and smaller at the top.

7. The electromagnetic tin pump according to claim 5, characterized in that: The groove (15) is provided with positioning posts (16) on the left and right sides respectively. The positive electrode (5) is provided with a first positioning hole (53) for the corresponding positioning post (16) to be inserted. The negative electrode (6) is provided with a second positioning hole (63) for the corresponding positioning post (16) to be inserted. The positive electrode (5) is installed between the two housings (13) through the cooperation of the first positioning hole (53) and the corresponding positioning post (16). The negative electrode (6) is installed between the two housings (13) through the cooperation of the second positioning hole (63) and the corresponding positioning post (16).

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