A magnetic steel temperature limiter and electric rice cooker

Abstract

The present invention provides a magnetic steel temperature limiter, comprising a soft magnet, a hard magnet, a hard support, a pull rod and an inner spring, wherein the hard magnet is fixed on the surface of the hard support facing the soft magnet, and the magnetic steel temperature limiter also comprises an outer shell, an inner shell and an inner card, wherein the outer shell is provided with an inner cavity, the upper bottom surface of the inner cavity of the outer shell is provided with a first through hole, the inner card is provided with a second through hole, the soft magnet is fixed to the upper bottom surface of the inner cavity of the outer shell through the inner card, and one end of the soft magnet passes through the first through hole, and the other end of the soft magnet passes through the second through hole, one end of the pull rod is fixedly connected to the bottom of the hard support, and the other end of the pull rod passes through the lower bottom surface of the inner cavity of the inner shell and can be movably arranged, the inner shell is sleeved in the inner cavity of the outer shell and is slidably connected to the inner cavity of the outer shell, and the inner spring is arranged between the inner card and the hard support. The present invention ensures that the electrical distance between the reeds of the rocker switch remains unchanged, reduces the risk of dry burning of the electric rice cooker, and avoids the problem of burning of the heating plate of the electric rice cooker. Accordingly, the present invention provides an electric rice cooker.

Description

Technical Field

[0001] The invention relates to the technical field of magnetic steel temperature limiters, in particular to a magnetic steel temperature limiter and an electric rice cooker. Background Art

[0002] The magnetic steel temperature limiter is a temperature controller with hard magnetism and soft magnetism. It is mostly used in rice cookers. It is a mechanical device that can realize automatic power off of rice cookers. It is mainly composed of non-magnetic soft magnetism and permanent hard magnetism. When the hard magnetism is close to the soft magnetism at room temperature, the magnetic field of the hard magnetism will magnetize the soft magnetism, and then the two will be attracted. When the temperature rises to the Curie temperature of the soft magnetism, the magnetism of the soft magnetism will decrease or even disappear. The inner spring of the magnetic steel temperature limiter separates the hard magnetism from the soft magnetism, so that the pull rod pushes the rocker switch to achieve the purpose of automatic power off.

[0003] The current magnetic steel temperature limiter has a potential safety hazard. When the rice cooker is cooked, the magnetic steel temperature limiter pushes the seesaw switch and the rice cooker is automatically powered off. At this time, if the inner pot of the rice cooker is removed, the magnetic steel temperature limiter will float upward under the action of the external spring, and then drive the seesaw to move, which will cause the distance between the reeds of the seesaw switch to decrease, making the electrical distance of the rice cooker seesaw switch insufficient, and then causing the seesaw switch to turn on. In this way, the rice cooker is at risk of burning the heating plate by dry burning, and in severe cases, there may even be a problem of partial melting. Summary of the invention

[0004] In order to overcome the potential safety hazard of the current magnetic steel temperature limiter, the present invention provides a magnetic steel temperature limiter and an electric rice cooker, and the specific technical scheme thereof is as follows:

[0005] A magnetic steel temperature limiter comprises a soft magnet, a hard magnet, a hard support, a pull rod and an inner spring, wherein the hard magnet is fixed on the surface of the hard support facing the soft magnet, and the magnetic steel temperature limiter also comprises an outer shell, an inner shell and an inner card, wherein the outer shell is provided with an inner cavity, the upper bottom surface of the inner cavity of the outer shell is provided with a first through hole, and the inner card is provided with a second through hole, the soft magnet is fixed to the upper bottom surface of the inner cavity of the outer shell through the inner card and one end of the soft magnet passes through the first through hole, and the other end of the soft magnet passes through the second through hole, one end of the pull rod is fixedly connected to the hard support, and the other end of the pull rod passes through the lower bottom surface of the inner cavity of the inner shell and is movably arranged, the inner shell is sleeved in the inner cavity of the outer shell and is slidably connected to the inner cavity of the outer shell, and the inner spring is arranged between the inner card and the hard support.

[0006] When the inner pot is put into the electric rice cooker, the outer shell slides downward under the gravity of the inner pot, and the rocker switch is pressed at this time to push the pull rod, so that the soft magnet and the hard magnet are attracted, the rocker switch is turned on, and the electric rice cooker starts to heat.

[0007] When the temperature reaches the Curie temperature of the soft magnet, the soft magnet disappears. Under the action of the gravity of the hard support and the elastic force of the inner spring, the hard support moves downward, the pull rod pushes the seesaw switch, and the rice cooker automatically cuts off the power. When the inner pot is taken out, the outer shell floats upward under the action of the outer spring, and the inner spring props the outer shell and the inner shell apart. The position of the inner shell remains unchanged, and the seesaw will not be driven to move upward, ensuring that the electrical distance between the reeds of the seesaw switch remains unchanged. In this way, the safety hazards of the existing magnetic steel temperature limiter can be overcome, and the problem of dry burning and burning the heating plate of the rice cooker due to the reduced electrical distance between the reeds of the seesaw switch can be avoided.

[0008] Optionally, a buckle is provided on the inner card, and a slot is provided on the side wall of the inner cavity of the outer shell, and the buckle is buckled and connected to the slot.

[0009] The inner card is buckled with the card slot through a buckle, so the inner card and the soft magnet can be easily disassembled and replaced.

[0010] Optionally, a limit groove is provided on the side wall of the inner cavity of the outer shell, and a limit block protruding outward is provided on the opening edge of the inner shell, and the limit block is slidably connected to the limit groove. The moving direction of the inner shell can be limited by the limit block and the limit groove, so that the action of the magnetic steel temperature limiter is more stable and reliable.

[0011] Optionally, a positioning step is arranged on the outer side wall of the shell.

[0012] Optionally, the magnetic steel temperature limiter also includes an outer spring and a large cup, wherein the outer spring is sleeved on the outer wall of the outer shell and one end of the outer spring is clamped on the positioning step, and the other end of the outer spring is connected to the bottom surface of the inner cavity of the large cup.

[0013] The outer spring is clamped on the positioning step, which makes it easy to install and fix the outer spring.

[0014] Optionally, the outer spring, the outer shell and the inner shell are all located in the large cup.

[0015] Optionally, the other end of the pull rod passes through the bottom surface of the inner cavity of the large cup and is movably arranged.

[0016] Optionally, the hard magnet is made of permanent ferrite material.

[0017] Optionally, the soft magnetic material is made of temperature-sensitive ferrite material.

[0018] Correspondingly, the present invention provides an electric rice cooker, which comprises the magnetic steel temperature limiter described above.

[0019] The beneficial effect achieved by the present invention is as follows: when the inner pot is taken out, the outer shell floats upward under the action of the outer spring, and the inner spring opens the outer shell and the inner shell, and the position of the inner shell remains unchanged, and the seesaw will not be driven to move upward. In this way, the electrical distance between the reeds of the seesaw switch is ensured to remain unchanged, the risk of dry burning of the rice cooker is reduced, and the problem of burning of the heating plate of the rice cooker is avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The invention may be further understood from the following description taken in conjunction with the accompanying drawings, with emphasis placed on illustrating the principles of the embodiments.

[0021] Figure 1 It is a schematic diagram of the overall structure of a magnetic steel temperature limiter in an embodiment of the present invention;

[0022] Figure 2 It is a structural schematic diagram of a magnetic steel temperature limiter in an embodiment of the present invention when soft magnetism and hard magnetism are attracted;

[0023] Figure 3 It is a structural schematic diagram of a magnetic steel temperature limiter in an embodiment of the present invention when the soft magnetic and hard magnetic are separated;

[0024] Figure 4 It is a schematic diagram of the overall structure of an electric rice cooker in an embodiment of the present invention;

[0025] Figure 5 yes Figure 4 Enlarged view of point A in the middle.

[0026] Description of reference numerals:

[0027] 1. Soft magnet; 2. Hard magnet; 3. Hard support; 4. Pull rod; 5. Inner spring; 6. Outer shell; 7. Inner shell; 8. Inner card; 9. Buckle; 10. Card slot; 11. Limit slot; 12. Limit block; 13. Outer spring; 14. Large cup; 15. Positioning step. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with its embodiments.

[0029] The present invention is a magnetic steel temperature limiter and an electric rice cooker, and the following embodiments are described according to the accompanying drawings:

[0030] Embodiment 1:

[0031] like Figure 1As shown, a magnetic steel temperature limiter includes a soft magnet 1, a hard magnet 2, a hard support 3, a pull rod 4 and an inner spring 5. The hard magnet 2 is fixed on the surface of the hard support 3 facing the soft magnet 1. The hard magnet 2 is made of a permanent ferrite material, and the soft magnet 1 is made of a temperature-sensitive ferrite material. When the temperature of the soft magnet 1 exceeds its Curie temperature, the magnetism of the soft magnet 1 disappears.

[0032] like Figure 1 As shown, the magnetic steel temperature limiter also includes an outer shell 6, an inner shell 7 and an inner card 8, the outer shell 6 is provided with an inner cavity, the upper bottom surface of the inner cavity of the outer shell 6 is provided with a first through hole, the inner card 8 is provided with a second through hole, the soft magnet 1 is fixed to the upper bottom surface of the inner cavity of the outer shell 6 through the inner card 8 and one end of the soft magnet 1 passes through the first through hole, and is used to directly contact the bottom surface of the inner pot of the rice cooker. One end of the soft magnet 1 and the other end of the soft magnet 1 pass through the second through hole, one end of the pull rod 4 is fixedly connected to the hard support 3, and the other end of the pull rod 4 passes through the lower bottom surface of the inner cavity of the inner shell 7 and can be movably arranged, the inner shell 7 is sleeved in the inner cavity of the outer shell 6 and is slidably connected to the inner cavity of the outer shell 6, and the inner spring 5 is arranged between the inner card 8 and the hard support 3. Here, the upper bottom surface of the inner cavity of the shell 6 refers to the bottom surface of the shell 6 in contact with the bottom surface of the inner pot of the rice cooker, and the lower bottom surface of the inner cavity of the shell 6 refers to the bottom surface of the shell 6 not in contact with the bottom surface of the inner pot of the rice cooker.

[0033] In the existing magnetic steel temperature limiter, there is generally an aluminum cover between the soft magnet 1 and the inner pot of the rice cooker. There is contact thermal resistance between the soft magnet 1 and the inner pot of the rice cooker, that is, there is a temperature difference between the soft magnet 1 and the inner pot of the rice cooker, which makes the magnetic steel temperature limiter not accurate enough and the action accuracy is low.

[0034] In the magnetic steel temperature limiter described in this embodiment, one end of the soft magnet 1 is in direct contact with the bottom surface of the inner pot of the rice cooker, and there is no aluminum cover between the soft magnet 1 and the inner pot of the rice cooker, thereby eliminating the contact thermal resistance between the inner pot of the rice cooker and the soft magnet 1, and significantly reducing the temperature difference between the inner pot of the rice cooker and the soft magnet 1, thereby ensuring that the temperature of the soft magnet 1 and the temperature of the inner pot of the rice cooker rise synchronously, and once the temperature of the inner pot of the rice cooker reaches the Curie temperature point of the soft magnet 1, the magnetic steel temperature limiter can be activated. Therefore, compared with the existing magnetic steel temperature limiter, the magnetic steel temperature limiter described in this embodiment can improve the action accuracy.

[0035] like Figure 1 as well as Figure 2 As shown, when the inner pot is put into the rice cooker, the outer shell 6 slides downward under the gravity of the inner pot, and the rocker switch is pressed at this time to push the pull rod 4, so that the soft magnet 1 and the hard magnet 2 are attracted, the rocker switch is turned on, and the rice cooker starts to heat.

[0036] like Figure 1 , Figure 3 as well as Figure 5 As shown, when the temperature reaches the Curie temperature of the soft magnet 1, the magnetism of the soft magnet 1 disappears, and under the action of the gravity of the hard support 3 and the elastic force of the inner spring 5, the hard support 3 moves downward, and the pull rod 4 pushes the seesaw switch, and the electric rice cooker is automatically powered off. When the inner pot is taken out, the outer shell 6 floats upward under the action of the outer spring 13, and the inner spring 5 props the outer shell 6 and the inner shell 7 apart, and the position of the inner shell 7 remains unchanged, and the seesaw will not be driven to move upward, ensuring that the electrical distance between the reeds of the seesaw switch remains unchanged. In this way, the safety hazard existing in the existing magnetic steel temperature limiter can be overcome, and the problem of dry burning and burning the heating plate of the electric rice cooker due to the reduced electrical distance between the reeds of the seesaw switch can be avoided.

[0037] like Figure 1 As shown, the inner card 8 is provided with a buckle 9, and the side wall of the inner cavity of the shell 6 is provided with a slot 10, and the buckle 9 is buckled and connected with the slot 10. The inner card 8 is buckled with the slot 10 by the buckle 9, so that the inner card 8 and the soft magnet 1 can be easily disassembled and replaced.

[0038] A limiting groove 11 is provided on the side wall of the inner cavity of the outer shell 6, and a limiting block 12 protruding outward is provided on the opening edge of the inner shell 7, and the limiting block 12 is slidably connected with the limiting groove 11. The moving direction of the inner shell 7 can be limited by the limiting block 12 and the limiting groove 11, so that the action of the magnetic steel temperature limiter is more stable and reliable.

[0039] Accordingly, the present embodiment provides an electric rice cooker, which includes the magnetic steel temperature limiter described above. When the inner pot is taken out, the outer shell 6 floats upward under the action of the outer spring 13, and the inner spring 5 opens the outer shell 6 and the inner shell 7, and the position of the inner shell 7 remains unchanged, and the seesaw will not be driven to move upward. In this way, the electrical distance between the reeds of the seesaw switch remains unchanged, so the risk of dry burning of the electric rice cooker described in the present embodiment can be reduced, and the problem of burning of the heating plate of the electric rice cooker can be avoided.

[0040] Embodiment 2:

[0041] like Figure 1 As shown, a magnetic steel temperature limiter includes a soft magnet 1, a hard magnet 2, a hard support 3, a pull rod 4 and an inner spring 5. The hard magnet 2 is fixed on the surface of the hard support 3 facing the soft magnet 1. The hard magnet 2 is made of a permanent ferrite material, and the soft magnet 1 is made of a temperature-sensitive ferrite material. When the temperature of the soft magnet 1 exceeds its Curie temperature, the magnetism of the soft magnet 1 disappears.

[0042] like Figure 1As shown, the magnetic steel temperature limiter also includes an outer shell 6, an inner shell 7 and an inner card 8, the outer shell 6 is provided with an inner cavity, the upper bottom surface of the inner cavity of the outer shell 6 is provided with a first through hole, the inner card 8 is provided with a second through hole, the soft magnet 1 is fixed to the upper bottom surface of the inner cavity of the outer shell 6 through the inner card 8 and one end of the soft magnet 1 passes through the first through hole, and is used to directly contact the bottom surface of the inner pot of the rice cooker. One end of the soft magnet 1 and the other end of the soft magnet 1 pass through the second through hole, one end of the pull rod 4 is fixedly connected to the hard support 3, and the other end of the pull rod 4 passes through the lower bottom surface of the inner cavity of the inner shell 7 and can be movably arranged, the inner shell 7 is sleeved in the inner cavity of the outer shell 6 and is slidably connected to the inner cavity of the outer shell 6, and the inner spring 5 is arranged between the inner card 8 and the hard support 3. Here, the upper bottom surface of the inner cavity of the shell 6 refers to the bottom surface of the shell 6 in contact with the bottom surface of the inner pot of the rice cooker, and the lower bottom surface of the inner cavity of the shell 6 refers to the bottom surface of the shell 6 not in contact with the bottom surface of the inner pot of the rice cooker.

[0043] In the existing magnetic steel temperature limiter, there is generally an aluminum cover between the soft magnet 1 and the inner pot of the rice cooker. There is contact thermal resistance between the soft magnet 1 and the inner pot of the rice cooker, that is, there is a temperature difference between the soft magnet 1 and the inner pot of the rice cooker, which makes the magnetic steel temperature limiter not accurate enough and the action accuracy is low.

[0044] In the magnetic steel temperature limiter described in this embodiment, one end of the soft magnet 1 is in direct contact with the bottom surface of the inner pot of the rice cooker, and there is no aluminum cover between the soft magnet 1 and the inner pot of the rice cooker, thereby eliminating the contact thermal resistance between the inner pot of the rice cooker and the soft magnet 1, and significantly reducing the temperature difference between the inner pot of the rice cooker and the soft magnet 1, thereby ensuring that the temperature of the soft magnet 1 and the temperature of the inner pot of the rice cooker rise synchronously, and once the temperature of the inner pot of the rice cooker reaches the Curie temperature point of the soft magnet 1, the magnetic steel temperature limiter can be activated. Therefore, compared with the existing magnetic steel temperature limiter, the magnetic steel temperature limiter described in this embodiment can improve the action accuracy.

[0045] like Figure 1 as well as Figure 2 As shown, when the inner pot is put into the rice cooker, the outer shell 6 slides downward under the gravity of the inner pot, and the rocker switch is pressed at this time to push the pull rod 4, so that the soft magnet 1 and the hard magnet 2 are attracted, the rocker switch is turned on, and the rice cooker starts to heat.

[0046] like Figure 1 , Figure 3 as well as Figure 5As shown, when the temperature reaches the Curie temperature of the soft magnet 1, the magnetism of the soft magnet 1 disappears, and under the action of the gravity of the hard support 3 and the elastic force of the inner spring 5, the hard support 3 moves downward, and the pull rod 4 pushes the seesaw switch, and the electric rice cooker is automatically powered off. When the inner pot is taken out, the outer shell 6 floats upward under the action of the outer spring 13, and the inner spring 5 props the outer shell 6 and the inner shell 7 apart, and the position of the inner shell 7 remains unchanged, and the seesaw will not be driven to move upward, ensuring that the electrical distance between the reeds of the seesaw switch remains unchanged. In this way, the safety hazard existing in the existing magnetic steel temperature limiter can be overcome, and the problem of dry burning and burning the heating plate of the electric rice cooker due to the reduced electrical distance between the reeds of the seesaw switch can be avoided.

[0047] like Figure 1 As shown, the inner card 8 is provided with a buckle 9, and the side wall of the inner cavity of the shell 6 is provided with a slot 10, and the buckle 9 is buckled and connected with the slot 10. The inner card 8 is buckled with the slot 10 by the buckle 9, so that the inner card 8 and the soft magnet 1 can be easily disassembled and replaced.

[0048] A limiting groove 11 is provided on the side wall of the inner cavity of the outer shell 6, and a limiting block 12 protruding outward is provided on the opening edge of the inner shell 7, and the limiting block 12 is slidably connected with the limiting groove 11. The moving direction of the inner shell 7 can be limited by the limiting block 12 and the limiting groove 11, so that the action of the magnetic steel temperature limiter is more stable and reliable.

[0049] like Figure 1 as well as Figure 4 as well as Figure 5 As shown, the magnetic steel temperature limiter also includes an outer spring 13 and a large cup 14, and a positioning step 15 is provided on the outer side wall of the outer shell 6. The outer spring 13 is sleeved on the outer side wall of the outer shell 6 and one end of the outer spring 13 is clamped on the positioning step 15, and the other end of the outer spring 13 is connected to the bottom surface of the inner cavity of the large cup 14. The outer spring 13, the outer shell 6 and the inner shell 7 are all located in the large cup 14, and the other end of the pull rod 4 passes through the bottom surface of the inner cavity of the large cup 14 and is movably arranged.

[0050] The outer spring 13 is clamped on the positioning step 15, which can facilitate the installation and fixation of the outer spring 13.

[0051] Accordingly, the present embodiment provides an electric rice cooker, which includes the magnetic steel temperature limiter described above. When the inner pot is taken out, the outer shell 6 floats upward under the action of the outer spring 13, and the inner spring 5 opens the outer shell 6 and the inner shell 7, and the position of the inner shell 7 remains unchanged, and the seesaw will not be driven to move upward. In this way, the electrical distance between the reeds of the seesaw switch remains unchanged, so the risk of dry burning of the electric rice cooker described in the present embodiment can be reduced, and the problem of burning of the heating plate of the electric rice cooker can be avoided.

[0052] In summary, the magnetic steel temperature limiter and rice cooker disclosed in the present invention have the following beneficial technical effects: when the inner pot is taken out, the outer shell floats upward under the action of the outer spring, and the inner spring opens the outer shell and the inner shell, and the position of the inner shell remains unchanged, and the seesaw will not be driven to move upward. In this way, the electrical distance between the reeds of the seesaw switch is ensured to remain unchanged, the risk of dry burning of the rice cooker is reduced, and the problem of burning of the heating plate of the rice cooker is avoided.

[0053] The above embodiments should be understood to be only used to illustrate the present invention and not to limit the protection scope of the present invention. After reading the contents of the present invention, technicians can make various changes or modifications to the present invention, and these equivalent changes and modifications also fall within the scope defined by the claims of the present invention.

Claims

1. A magnetic steel temperature limiter, comprising a soft magnet, a hard magnet, a hard support, a pull rod and an inner spring, wherein the hard magnet is fixed on the surface of the hard support facing the soft magnet, characterized in that: The magnetic steel temperature limiter also includes an outer shell, an inner shell and an inner card, the outer shell is provided with an inner cavity, the upper bottom surface of the inner cavity of the outer shell is provided with a first through hole, the inner card is provided with a second through hole, the soft magnet is fixed to the upper bottom surface of the inner cavity of the outer shell through the inner card and one end of the soft magnet passes through the first through hole, the other end of the soft magnet passes through the second through hole, one end of the pull rod is fixedly connected to the hard support, the other end of the pull rod passes through the lower bottom surface of the inner cavity of the inner shell and is movably arranged, the inner shell is sleeved in the inner cavity of the outer shell and is slidably connected to the inner cavity of the outer shell, and the inner spring is arranged between the inner card and the hard support; the inner A buckle is provided on the card, and a slot is provided on the side wall of the inner cavity of the shell, and the buckle is buckled and connected with the slot; a limiting groove is provided on the side wall of the inner cavity of the shell, and a limiting block protruding outward is provided on the opening edge of the inner shell, and the limiting block is slidably connected with the limiting groove; a positioning step is arranged on the outer wall of the shell; the magnetic steel temperature limiter also includes an outer spring and a large cup, the outer spring is sleeved on the outer wall of the shell and one end of the outer spring is clamped on the positioning step, and the other end of the outer spring is connected to the bottom surface of the inner cavity of the large cup; the hard magnet is made of permanent magnet ferrite material, and the soft magnet is made of temperature-sensitive ferrite material.

2. A magnetic steel temperature limiter as claimed in claim 1, characterized in that: The outer spring, the outer shell and the inner shell are all located in the large cup.

3. A magnetic steel temperature limiter as claimed in claim 2, characterized in that: The other end of the pull rod passes through the bottom surface of the inner cavity of the large cup and is movably arranged.

4. A magnetic steel temperature limiter as claimed in claim 3, characterized in that: The hard magnet is made of permanent ferrite material.

5. A magnetic steel temperature limiter as claimed in claim 4, characterized in that: The soft magnetic material is made of temperature-sensitive ferrite material.

6. An electric rice cooker, characterized in that: It comprises the magnetic steel temperature limiter as described in any one of claims 1 to 5.

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