CN211173644U - Door magnetic switch for household electrical appliance - Google Patents

Abstract

The utility model discloses a door magnetic switch for household appliances, which comprises an electromagnet assembly and a permanent magnet interacting with each other. The electromagnet assembly includes an electromagnet coil and a metal core. The metal core is fixed inside the electromagnet coil; the electromagnet coil is electrically connected with a driving circuit, The drive circuit is provided with a rectifier bridge stack that converts the alternating current of the input electromagnetic coil into direct current, the electromagnet body has a first mating end face that interacts with the permanent magnet, the permanent magnet has a second mating end face that interacts with the electromagnet body, and the two The mating end faces are arranged opposite to each other, and the positions are corresponding. When the electromagnetic coil is energized, the magnetic polarity of the first mating end face is the same as the magnetic polarity of the second mating end face, and a repulsive force is generated between the electromagnet body and the permanent magnet. , the magnetism of the electromagnet body disappears, and an attractive force is generated between the metal core and the permanent magnet. The door magnetic switch disclosed by the utility model pushes open the electric door through magnetic force, the thrust is stable and reliable, no noise is generated, and the service life is long.

Description

A household appliance door magnetic switch

technical field

The utility model belongs to the technical field of household appliances, in particular to a door magnetic switch for household appliances.

Background technique

In order to facilitate the use of the existing household appliances and realize automation, the doors or windows of the existing household appliances are usually opened and closed by means of a mechanical switch, and the door of the appliance is also controlled by means of electromagnetic action, so that the door of the household appliance can be operated without manual operation. It can be opened by operation, but most of the existing magnetic door switches use electromagnets to control the movement of a push rod to push open the electrical door. This kind of magnetic door switch has the following disadvantages. And in order to overcome the locking force, the electromagnet needs to exert enough thrust on the push rod, so when the push rod hits the electrical door, it will generate a lot of noise, and frequent impacts will also cause damage to the electrical door; in order to match the movement of the push rod, it is necessary to Provide enough installation space for the door magnetic switch, which affects the compactness of the electrical structure; the push rod is in a movable state, and its installation stability and movement reliability are not high, resulting in a short service life of the door magnetic switch.

SUMMARY OF THE INVENTION

In order to solve the above technical problems, the utility model provides a door magnetic switch for household appliances.

The utility model purpose of the present utility model is achieved through the following technical solutions:

A door magnetic switch for household appliances includes an electromagnet assembly and a permanent magnet that interact with each other. The electromagnet assembly includes an electromagnet body and a drive circuit. The electromagnet body includes an electromagnetic coil and a metal core that can be magnetized by the magnetic field of the electromagnetic coil. The core is fixed inside the electromagnetic coil; the electromagnetic coil is electrically connected with the driving circuit, and the driving circuit is provided with a rectifier bridge stack that converts the alternating current input into the electromagnetic coil into direct current, so as to keep the polarity fixed when the electromagnetic coil is energized, and the electromagnet body It has a first mating end face that interacts with the permanent magnet, and the permanent magnet has a second mating end face that interacts with the electromagnet body. The two mating end faces are arranged opposite to each other and have corresponding positions. When the electromagnetic coil is energized, the magnetic pole of the first mating end face The polarity of the electromagnet is the same as the magnetic polarity of the second mating end face, and a repulsive force is generated between the electromagnet body and the permanent magnet. When the electromagnetic coil is powered off, the magnetism of the electromagnet body disappears, and an attractive force is generated between the metal core and the permanent magnet. In this technical solution, through the arrangement of the rectifier bridge stack, the polarity of the electromagnet body can be fixed, so as to meet the matching requirements between it and the permanent magnet. Compared with the push rod of mechanical movement, the magnetic force is more stable and reliable, and the service life is Longer, and will not cause damage to the electrical door; a metal core is fixed in the electromagnetic coil. When the electrical door needs to be opened, the electromagnetic coil is energized, the metal core is magnetized by the magnetic field of the electromagnetic coil, and the magnetized iron core also becomes a In this way, since the magnetic poles of the two mating end faces are consistent, they repel each other, so that the permanent magnet drives the electrical door to move back to open the electrical door; the electromagnetic coil is powered off, the magnetism of the metal core will disappear, and there is attraction between the permanent magnet When the electrical door is closed, the permanent magnet on the electrical door will be attracted to the metal core.

Preferably, the drive circuit is provided with a PTC resistor, and the PTC resistor is connected in series between the power input end and the rectifier bridge stack. The PTC resistor can prevent the electromagnetic coil from being energized and heated for a long time, resulting in an excessively high temperature rise, so as to stabilize the performance of the door magnetic switch.

Preferably, the electromagnetic coil is wound on a coil frame, the coil frame includes two oppositely arranged outer end walls and an inner end wall, a coil column is arranged between the outer end wall and the inner end wall, and the coil column is a hollow cylinder body, and the electromagnetic coil is wound on the outer peripheral surface of the coil column. Through the arrangement of the coil frame, the structure of the electromagnet body can be made more stable, the coil column core is cylindrical, and the electromagnetic coil wound on it is also cylindrical, so that the electromagnetic coil can generate an aligned magnetic field along the axial direction, making it The thrust to the electrical door is more stable and reliable.

Preferably, the metal core includes a cylindrical main body portion and a limiting portion located at the rear end of the main body portion, and the main body portion is tightly embedded in the coil column and arranged coaxially with the coil column. The coaxial arrangement of the metal core and the coil column can enhance the magnetic field of the electromagnet body, and can make the structure of the electromagnet body more compact.

Preferably, the limiting portion includes a limiting boss, and a connecting column located between the limiting boss and the main body. The limiting boss is coaxial with the connecting column and the main body. The outer diameter of the limiting boss is Smaller than the outer diameter of the main body, but larger than the outer diameter of the connecting post. The setting of the limiting portion is to ensure the installation stability of the metal core and to prevent it from moving back and forth in the axial direction under the action of magnetic force.

Preferably, one end of the coil column close to the inner end wall is a limiting end, and the inner wall of the limiting end is provided with a limiting rib along the circumferential direction. Limiting rib. When the electromagnet and the permanent magnet generate a repulsive force, the limiting rib and the limiting portion of the metal core can effectively prevent the metal core from moving backward in the axial direction.

Preferably, the limit end of the coil column is fastened with an end cover, the limit part of the metal core is limited in the end cover, and the outer peripheral surface of the annular side wall of the end cover is provided with a limiter rib along the circumferential direction. Card hole. The limiting rib is clamped in the clamping hole, which can further improve the installation stability of the metal core.

Preferably, the annular side wall of the end cap includes a diameter reducing section and an expanding diameter end, the inner diameter of the diameter reducing end matches the outer diameter of the connecting column, the inner diameter of the expanding diameter end matches the outer diameter of the limiting boss, and the connecting column It is limited to the reduced diameter end, and the limiting boss is limited to the enlarged diameter end. When the permanent magnet attracts the metal core, the cooperation between the limit part of the metal core and the end cover and the cooperation of the limit protrusion can effectively prevent the metal core from moving forward in the axial direction and being pulled out by the permanent magnet.

Preferably, the central axis of the metal core is perpendicular to the first mating end face. This arrangement can make the interaction force between the electromagnet body and the permanent magnet more reliable and effective.

Preferably, the first mating end face of the electromagnet body is flush with the outer end wall of the coil former. The above arrangement can make the contact and cooperation between the electromagnet body and the permanent magnet more reliable.

Preferably, the metal core is made of soft iron or silicon steel material. Using soft iron or silicon steel as the metal core can make the metal core demagnetize immediately after the electromagnetic coil is powered off, so as to ensure that the permanent magnet can be adsorbed on the metal core.

Compared with the prior art, the utility model has the following beneficial effects: the magnetic door switch disclosed by the utility model pushes open the electrical door through magnetic force, which is more stable and reliable compared with the thrust applied by the push rod, does not generate noise, and has a long service life. Long; the metal core is fixed in the electromagnetic coil, and there is no need to provide displacement space for it, which makes the structure of the entire door magnetic switch more compact and saves installation space; through the improvement of the structure of the metal core and the coil frame, and the matching of the end cover can ensure The installation stability of the metal core prevents it from moving in the axial direction under the action of magnetic force, thereby further improving the reliability of the door magnetic switch.

Description of drawings

Fig. 1 is the structural representation of the utility model;

2 is a schematic structural diagram of an electromagnet assembly in the utility model;

3 is a schematic diagram of the internal structure of the electromagnet assembly in the utility model;

4 is another schematic diagram of the internal structure of the electromagnet assembly in the present invention;

5 is a schematic structural diagram of a drive circuit in the utility model;

FIG. 6 is a schematic diagram of the structure of the coil frame in the utility model;

7 is a schematic diagram of the structure of the metal core in the utility model;

Figure 8 is a schematic diagram of the structure of the middle end cap of the present invention;

Marked in the figure: 10 electromagnet assembly; 11 first mating end face; 12 shell; 13 metal core; 131 main body part; 132 connecting part; 133 limit boss; 14 coil frame; 141 coil column; 142 outer end wall; 143 Inner end wall; 144 limit ribs; 15 rectifier bridge stacks; 16 PTC resistors; 17 electromagnetic coils; 18 end caps; 181 card holes; 20 permanent magnets.

Detailed ways

The present utility model will be further described below in conjunction with the embodiments represented by the accompanying drawings:

Embodiment 1, referring to FIGS. 1-8 , this embodiment discloses a magnetic door switch for household appliances, which includes an electromagnet assembly 10 and a permanent magnet that interact and are arranged separately. The electromagnet assembly 10 is applied to a drum washing machine, wherein the electromagnet assembly 10 is installed Behind the front wall of the washing machine body, a permanent magnet is integrated into the washing machine door; the electromagnet assembly 10 includes an electromagnet body and a drive circuit, the electromagnet body includes an electromagnetic coil 17 and a metal core 13 that can be magnetized by the magnetic field of the electromagnetic coil 17, The metal core 13 is fixed inside the electromagnetic coil 17; the electromagnetic coil 17 is electrically connected to a driving circuit, and the driving circuit is provided with a rectifier bridge stack 15 that converts the alternating current input to the electromagnetic coil 17 into direct current, so as to keep the electromagnetic coil 17 energized when the The polarity is fixed. Through the setting of the rectifier bridge stack 15, the polarity of the electromagnet body can be fixed, so as to meet the matching requirements between it and the permanent magnet. Compared with the push rod of mechanical movement, the magnetic force is more stable and reliable, and the service life is longer, and will not cause damage to the electrical door; the electromagnet body has a first matching end face 11 that interacts with the permanent magnet, the permanent magnet has a second matching end face that interacts with the electromagnet body, and the two matching end faces are arranged opposite to each other. And the positions are corresponding, when the electromagnetic coil 17 is energized, the magnetic polarity of the first mating end face 11 is the same as that of the second mating end face. In this embodiment, the magnetic polarities of the first mating end face 11 and the second mating end face are both N poles. , a repulsive force is generated between the electromagnet body and the permanent magnet. When the electromagnetic coil 17 is powered off, the magnetism of the electromagnet body disappears, and an attractive force is generated between the metal core 13 and the permanent magnet. The metal core 13 fixed in the electromagnetic coil 17 has Two functions, when the electrical door needs to be opened, the electromagnetic coil 17 is energized, the metal core 13 is magnetized by the magnetic field of the electromagnetic coil 17, and the magnetized iron core also becomes a magnet. The magnetic field strength of the main body is enhanced to ensure that it can provide enough thrust for the washing machine door to overcome the locking force to open the washing machine door. When the washing machine door is closed, the electromagnetic coil 17 is powered off, the magnetism of the metal core 13 will disappear, and the permanent magnet will be generated. Attractive, increase the locking force of the washing machine door.

In addition to being connected with the rectifier bridge stack 15, the drive circuit is also provided with a PTC resistor 16, the PTC resistor 16 is connected in series between the power input end and the rectifier bridge stack 15, and the PTC resistor 16 is arranged to ensure that the electromagnetic coil 17 is at the rated current. At the same time, the electromagnetic coil 17 can be prevented from being energized and heated for a long time, resulting in an excessively high temperature rise, so as to stabilize the use performance of the magnetic door switch.

The electromagnetic coil 17 is wound on the coil frame 14. The coil frame 14 includes two oppositely arranged outer end walls 142 and inner end walls 143. A coil column 141 is arranged between the outer end wall 142 and the inner end wall 143. The coil column 141 is a hollow cylinder, the electromagnetic coil 17 is wound on the outer peripheral surface of the coil column 141, the structure of the electromagnet body can be made more stable by the arrangement of the coil frame 14, the core of the coil column 141 is cylindrical, and the electromagnetic coil wound on it. The coil 17 is also cylindrical, which enables the electromagnet coil to generate an aligned magnetic field in the axial direction, so that the thrust force on the electrical door is more stable and reliable.

In order to ensure the installation stability of the metal core 13 and prevent the metal core 13 from moving in the axial direction under the action of magnetic force, the metal core 13 includes a cylindrical main body portion 131 and a limiting portion located at the rear end of the main body portion 131. The main body portion 131 is tightly embedded in the The coil column 141 is arranged coaxially with the coil column 141; the limiting portion includes a limiting boss 133, and a connecting column 132 located between the limiting boss 133 and the main body 131, the limiting boss 133 and the The connection post 132 and the main body 131 are coaxially arranged. The outer diameter of the limiting boss 133 is smaller than the outer diameter of the main body 131 , but larger than the outer diameter of the connection post 132 . The restriction is provided to ensure the installation stability of the metal core 13 . , to prevent it from moving back and forth in the axial direction under the action of the magnetic force; the end of the coil column 141 close to the inner end wall 143 is the limit end, the inner wall of the limit end is provided with a limit rib 144 along the circumferential direction, and the metal core 13 is embedded in the coil When the column 141 is in the position, the rear end surface of the main body portion 131 abuts against the limiting rib 144. When the electromagnet body and the permanent magnet generate a repulsive force, the limiting rib 144 cooperates with the limiting portion of the metal core 13 to effectively avoid metal The core 13 moves back in the axial direction; the limit end of the coil column 141 is buckled with an end cover 18 , the limit part of the metal core 13 is limited in the end cover 18 , and the outer peripheral surface of the annular side wall of the end cover 18 is in the circumferential direction A clamping hole 181 matching the limiting rib 144 is opened, and the limiting rib 144 is clamped in the clamping hole 181, which can further improve the installation stability of the metal core 13; the annular side wall of the end cover 18 includes a reduced diameter section and the expanding section, the inner diameter of the reducing section matches the outer diameter of the connecting column 132, the inner diameter of the expanding section matches the outer diameter of the limiting boss 133, the connecting column 132 is limited to the reducing section, and the limiting boss 133 is limited to the diameter-expanding section. The end cap 18 is post-injection molding and can be closely matched with the limiting portion of the metal core 13 and the coil column 141. When the permanent magnet attracts the metal core 13, it passes through the limit of the metal core 13. The cooperation of the position with the end cover 18 and the coil frame 14 can effectively prevent the metal core 13 from moving forward in the axial direction and being pulled out by the permanent magnet.

In order to demagnetize the metal core 13 immediately after the electromagnetic coil is powered off and ensure that the permanent magnet can be adsorbed on the metal core 13, in this embodiment, the metal core 13 is made of soft iron; the central axis of the metal core 13 is perpendicular to the first mating end face 11 At the same time, it is also perpendicular to the front wall of the washing machine. This setting can make the interaction force between the electromagnet body and the permanent magnet more reliable and effective; in order to make the contact and cooperation between the electromagnet body and the permanent magnet more reliable, the electromagnet body The first mating end face 11 of the bobbin 14 is flush with the outer end wall 142 of the coil frame 14; the electromagnet body, the rectifier bridge stack 15, and the PTC resistor 16 are all sealed in the casing 12, and only the first mating end face 11 and the outer end of the coil frame 14. The wall 142 is exposed from the housing 12 and is flush with the side wall of the housing 12 .

The magnetic door switch for household appliances disclosed by the utility model has the advantages of compact structure, small size, long service life, stable and reliable magnetic force, and the electromagnet body can generate a repulsive force on the permanent magnet on the electric appliance door when it is energized, so as to push the electric appliance door open. When the power is off, the magnetic disappearance of the metal core 13 can attract the permanent magnet on the appliance door, thereby enhancing the lock and force of the appliance door. The metal core 13 has dual functions under the action of the magnetic force.

The specific embodiments described herein are merely illustrative of the spirit of the present invention. Those skilled in the art of the present invention can make various modifications or supplements to the described specific embodiments or replace them in similar ways, but will not deviate from the spirit of the present invention or go beyond the appended claims the defined range.

Claims (10)

1. A door magnetic switch for household appliances, characterized by comprising an electromagnet assembly (10) and a permanent magnet (20) that interact with each other, the electromagnet assembly (10) comprising an electromagnet body and a drive circuit, the electromagnet body It includes an electromagnetic coil (17) and a metal core (13) that can be magnetized by the magnetic field of the electromagnetic coil (17). The metal core (13) is fixed inside the electromagnetic coil (17); The driving circuit is provided with a rectifier bridge stack (15) that converts the alternating current of the input electromagnetic coil (17) into direct current, so as to keep the polarity of the electromagnetic coil (17) fixed when it is energized, and the electromagnet body has a connection with the permanent magnet (20). The first mating end face (11) that acts, the permanent magnet (20) has a second mating end face that interacts with the electromagnet body, the two mating end faces are arranged opposite to each other, and the positions are corresponding, when the electromagnetic coil (17) is energized, the first The magnetic polarity of the mating end face (11) is the same as the magnetic polarity of the second mating end face, and a repulsive force is generated between the electromagnet body and the permanent magnet (20). 13) An attractive force is generated between the permanent magnet (20). 2 . The magnetic door switch for household appliances according to claim 1 , wherein the electromagnetic coil ( 17 ) is wound on a coil frame ( 14 ), and the coil frame ( 14 ) comprises two oppositely arranged outer end walls ( 2 . 142) and the inner end wall (143), a coil column (141) is arranged between the outer end wall (142) and the inner end wall (143), the coil column (141) is a hollow cylinder, and the electromagnetic coil (17) It is wound around the outer peripheral surface of the coil column (141). 3 . The magnetic door switch for household appliances according to claim 2 , wherein the metal core ( 13 ) comprises a cylindrical main body portion ( 131 ) and a limiting portion located at the rear end of the main body portion ( 131 ), and the main body portion ( 131 ). 131) is tightly embedded in the coil column (141), and is arranged coaxially with the coil column (141). 4 . The magnetic door switch for household appliances according to claim 3 , wherein the limiting portion comprises a limiting boss ( 133 ), and is located between the limiting boss ( 133 ) and the main body portion ( 131 ). 5 . The connecting column (132), the limiting boss (133) is coaxially arranged with the connecting column (132) and the main body (131), and the outer diameter of the limiting boss (133) is smaller than the outer diameter of the main body (131), But larger than the outer diameter of the connecting post (132). 5 . The magnetic door switch for household appliances according to claim 4 , wherein one end of the coil column ( 141 ) close to the inner end wall ( 143 ) is a limit end, and the inner wall of the limit end is provided with a limit position along the circumferential direction. 6 . The rib (144), when the metal core (13) is embedded in the coil column (141), the rear end surface of the main body part (131) abuts against the limiting rib (144). 6 . The magnetic door switch for household appliances according to claim 5 , wherein an end cover ( 18 ) is fastened to the limit end of the coil column ( 141 ), and the limit part of the metal core ( 13 ) is limited to the end cover. 7 . In (18), the outer peripheral surface of the annular side wall of the end cover (18) is provided with a clamping hole (181) matching the limiting rib (144) along the circumferential direction. 7 . The magnetic door switch for household appliances according to claim 6 , wherein the annular side wall of the end cover ( 18 ) comprises a diameter-reducing section and an expanding-diameter section, and the inner diameter of the diameter-reducing section is connected to the connecting column ( 132 ). 8 . The inner diameter of the expanding section matches the outer diameter of the limiting boss (133), the connecting column (132) is limited to the reducing section, and the limiting boss (133) is limited to the expanding end. 8. The door magnetic switch for household appliances according to any one of claims 1-7, wherein the drive circuit is provided with a PTC resistor, and the PTC resistor is connected in series with the power input end and the rectifier bridge stack (15) between. 9. The magnetic door switch for household appliances according to any one of claims 2-7, characterized in that the first mating end surface (11) of the electromagnet body and the outer end wall (142) of the coil frame (14) flush. 10. The magnetic door switch for household appliances according to any one of claims 3-7, wherein the central axis of the metal core (13) is perpendicular to the first mating end surface (11).

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