Linear motor for small household appliance

Abstract

Disclosed is a linear motor for a small household appliance, comprising a housing and an iron core. Upper and lower inner side walls of the iron core are each provided with at least one salient pole, and the salient poles on the upper and lower sides are offset from each other. Coil windings are wound on the salient poles. A guide base is disposed at the bottom of the inside of the housing. A magnet support is slidably disposed in the housing, and a drive head is disposed on the magnet support at a position adjacent to an open end of the housing. A magnet assembly is slidably disposed in the magnet support. The magnet assembly is provided with at least one steel magnet. Upper and lower sides of the magnet support are each provided with at least one window, the positions of the windows being opposite the positions of the salient poles. The guide base is provided with a switching slot, the magnet assembly is provided with a pin, and the pin is movably inserted inside the switching slot, so that when the coil windings are energized to generate a magnetic field identical to that of the steel magnet, the magnet support drives the magnet assembly and the drive head to slide left and right, while the magnet assembly slides up and down relative to the magnet support, causing the steel magnet to be inserted into a corresponding window. The output smoothness of the linear motor is improved, production costs are reduced, and the motion inertia of the entire movable part is reduced.

Description

A linear motor for small household appliances Technical Field

[0001] This invention relates to the field of motor technology, and in particular to a linear motor for small household appliances. Background Technology

[0002] Due to size and cost constraints, most linear motors used in small household appliances are permanent magnet synchronous motors. Because of the attraction between the magnets and the stator core, there is a cogging torque, which causes the output torque provided by the linear motor to fluctuate periodically with the same number of pole pairs as the number of pole pairs. This periodic fluctuation makes it impossible for the rotor of the linear motor to provide a sufficiently linear and smooth output torque, thus reducing the user experience. Technical issues

[0003] The purpose of this invention is to overcome the above-mentioned shortcomings and provide a linear motor for small household appliances that can reduce the influence of cogging torque on the output torque of the linear motor, improve the output smoothness of the linear motor, reduce production costs, and reduce the motion inertia of the entire moving part. Technical solutions

[0004] To achieve the above objectives, the specific solution of the present invention is as follows: A linear motor for small household appliances includes a housing and an iron core disposed within the housing. At least one salient pole is provided on both the upper and lower inner walls of the iron core, with the salient poles on the upper and lower sides staggered. A coil winding is wound around the salient pole. A guide seat is provided at the bottom of the housing. A magnet support is slidably disposed within the housing. A head is provided on the magnet support near the opening end of the housing. A magnet assembly is slidably disposed within the magnet support. The magnet assembly has at least one magnet. At least one window is provided on both the upper and lower sides of the magnet support. The window corresponds to the position of the salient pole.

[0005] The guide seat is provided with a switching groove, and the magnet assembly is provided with a locking pin. The locking pin is movably embedded in the switching groove so that when the coil winding is energized to generate the same magnetic field as the magnet, the magnet support drives the magnet assembly and the head to slide left and right, while the magnet assembly slides up and down relative to the magnet support, so that the magnet is embedded in the corresponding window.

[0006] Optionally, the upper and lower inner walls of the iron core are each provided with two salient poles at intervals; the magnet assembly is provided with two magnets; and the upper and lower sides of the magnet support are each provided with two windows.

[0007] Optionally, the switching groove includes a first section, a second section, a third section, and a fourth section connected end to end; a first step is provided between the first section and the second section, a second step is provided between the second section and the third section, and a third step is provided between the third section and the fourth section; the bottom surfaces of the first section, the second section, and the fourth section are all inclined surfaces, and the depth of the first section near the fourth section is greater than the depth of the first section near the second section, the depth of the second section near the first section is less than the depth of the second section near the third section, and the depth of the fourth section near the third section is less than the depth of the fourth section near the first section; a smooth transition inclined surface is provided in the third section; the first section and the third section are both straight grooves and are parallel to each other; the second section and the fourth section are both curved grooves;

[0008] The locking pin is elastically set on the magnet assembly.

[0009] Optionally, the magnet assembly includes a magnet slider, with two magnets disposed on the left and right sides of the magnet slider. The magnet slider has a receiving hole on the side near the guide seat, and a spring is provided in the receiving hole. A locking pin is slidably inserted into the receiving hole and connected to the spring.

[0010] Optionally, a guide plate is provided on the side of the magnet support near the guide seat, and a clearance hole is provided on the guide plate corresponding to the position of the locking pin. The guide plate is provided with a first guide groove on both sides of the clearance hole, and the outline shape of the first guide groove is the same as the outline shape of the second section or the fourth section.

[0011] The magnetic slider has first guide posts on both sides of the locking pin, and the first guide posts are movably embedded in the first guide groove.

[0012] Optionally, the guide plate is provided with second guide posts at both ends; the guide seat is provided with second guide grooves at both ends; the second guide posts are movably embedded in the second guide grooves.

[0013] Optionally, the inner wall of the magnet support is provided with two third guide grooves at intervals, the outline shape of the third guide grooves being the same as the outline shape of the second section or the fourth section; two third guide posts are provided at intervals on the side of the magnet slider near the opening end of the housing; the third guide posts are movably embedded in the third guide grooves.

[0014] Optionally, winding supports are provided at both ends of the iron core.

[0015] Optionally, the open end of the housing is provided with a guide rod, which slides through the outer wall of the guide rod.

[0016] Optionally, the head is slidably mounted on the guide rod via a linear bearing. Beneficial effects

[0017] The beneficial effects of this invention are as follows: By setting the magnet to a movable state and utilizing the cooperation of a locking pin and a switching slot, the magnet can switch between the windows on the upper and lower sides of the magnet support. This increases the distance between the magnet and the salient pole corresponding to the non-energized coil winding during the operation of the linear motor, thereby reducing the influence of cogging torque on the output torque of the linear motor and improving the output smoothness of the linear motor. At the same time, through the interaction between the up-and-down movement of the magnet and the salient poles on the upper and lower sides, the number of magnets required for the linear motor is only half the number of salient poles, significantly reducing production costs and lightening the weight of the magnet assembly, thereby reducing the motion inertia of the entire movable part. Attached Figure Description

[0018] Figure 1 is a perspective view of the present invention;

[0019] Figure 2 is a cross-sectional schematic diagram of the present invention;

[0020] Figure 3 is a perspective view of the fixing part of the present invention;

[0021] Figure 4 is a front view of the iron core of the present invention;

[0022] Figure 5 is a perspective view of the guide seat of the present invention;

[0023] Figure 6 is a perspective view of the active part of the present invention when the magnet is embedded in the upper window;

[0024] Figure 7 is a perspective view of the active part of the present invention when the magnet is embedded in the upper window;

[0025] Figure 8 is a perspective view of the movable part of the present invention when the magnet is embedded in the lower window;

[0026] Figure 9 is a schematic diagram of the structure of the magnet support of the present invention;

[0027] Figure 10 is a perspective view of the magnet assembly of the present invention;

[0028] Figure 11 is a cross-sectional schematic diagram of the magnet assembly of the present invention;

[0029] Figure 12 is a schematic diagram of the structure of the guide plate of the present invention;

[0030] Explanation of reference numerals in the attached drawings: 11. Housing; 12. Iron core; 121. Salient pole; 13. Coil winding; 14. Guide seat; 141. First section; 142. Second section; 143. Third section; 144. Fourth section; 145. First step; 146. Second step; 147. Third step; 148. Smooth transition slope; 149. Second guide groove; 15. Winding support; 16. Guide rod; 21. Magnet support; 211. Window; 212. Third guide groove; 22. Head; 231. Magnet; 232. Locking pin; 233. Magnet slider; 2331. Accommodation hole; 2332. First guide post; 2333. Third guide post; 234. Spring; 24. Guide plate; 241. Clearance hole; 242. First guide groove; 243. Second guide post; 25. Linear bearing. Embodiments of the present invention

[0031] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, but this is not to limit the scope of the invention to this.

[0032] As shown in Figures 1 to 12, the linear motor for small household appliances described in this embodiment includes a housing 11. The housing 11 includes a shell and a bottom cover fixedly installed at the rear end of the shell, such that the front end of the shell is an open end; the shell and the bottom cover enclose an installation space.

[0033] It also includes an iron core 12 disposed in the installation space of the housing 11. The upper and lower inner walls of the iron core 12 are provided with at least one convex pole 121, and the convex poles 121 on the upper and lower sides are staggered. Preferably, the projection portions of the convex poles 121 on the central cross section of the iron core 12 overlap. A coil winding 13 is wound on each convex pole 121. A guide seat 14 is provided on the inner bottom of the housing 11. A magnet support 21 is slidably disposed inside the housing 11. A head 22 is provided on the magnet support 21 near the opening end of the housing 11. A magnet assembly is slidably disposed inside the magnet support 21. The magnet assembly is provided with at least one magnet 231. At least one window 211 is provided on the upper and lower sides of the magnet support 21. Each window 211 corresponds to the position of the corresponding convex pole 121.

[0034] The guide seat 14 is provided with a switching groove, and the magnet assembly is provided with a locking pin 232. The locking pin 232 is movably embedded in the switching groove so that when the coil winding 13 is energized to generate the same magnetic field as the magnet 231, the magnet support 21 drives the magnet assembly and the head 22 to slide left and right, while the magnet assembly slides up and down relative to the magnet support 21, so that the magnet 231 is embedded in the corresponding window 211.

[0035] The housing 11, iron core 12, coil winding 13, and guide seat 14 form the fixed part; the magnet support 21, head 22, and magnet assembly form the movable part.

[0036] Specifically, in this embodiment of the linear motor, as shown in FIG6, the locking pin 232 is initially set to cooperate with the switching slot, so that the magnet assembly is located on the upper side, the magnet 231 of the magnet assembly is embedded in the upper window 211, and the upper side of the magnet 231 is opposite to the position of the salient pole 121 located on the upper side.

[0037] When the upper coil winding 13 is energized to generate a magnetic field identical to the magnetic pole on the upper side of the magnet 231, the magnet assembly slides downward under the action of the magnetic field. At this time, with the cooperation of the switching slot and the locking pin 232, the magnet support 21 slides to the left and drives the head 22 to move to the left. At the same time, the magnet assembly drives the magnet 231 to move downward relative to the magnet support 21, so that the magnet 231 is dislodged from the upper window 211 until the magnet 231 on the magnet assembly is embedded in the lower window 211, as shown in Figure 8. Thus, the lower side of the magnet 231 is opposite to the lower salient pole 121, which increases the distance between the magnet 231 and the salient pole 121 corresponding to the upper non-energized coil winding 13, thereby completing the state switching of the magnet assembly.

[0038] After the state switch is completed, the lower coil winding 13 is energized to generate a magnetic field that is the same as the magnetic pole on the lower side of the magnet 231, which pushes the magnet assembly to slide upward. At this time, the magnet support 21 drives the head 22 to move to the right. At the same time, the magnet 231 of the magnet assembly moves upward relative to the magnet support 21 until the magnet 231 of the magnet assembly is embedded in the upper window 211, as shown in Figures 6 and 7. This makes the upper side of the magnet 231 opposite to the upper salient pole 121, thus returning to the initial position. This increases the distance between the magnet 231 and the salient pole 121 corresponding to the lower non-energized coil winding 13, thus completing one reciprocating motion cycle.

[0039] In this embodiment, the magnet 231 is set to a movable state. By using the locking pin 232 in conjunction with the switching slot, the magnet 231 can switch between the windows 211 on the upper and lower sides of the magnet support 21. This increases the distance between the magnet 231 and the salient pole 121 corresponding to the non-energized coil winding 13 during the operation of the linear motor, thereby reducing the influence of cogging torque on the output torque of the linear motor and improving the output smoothness of the linear motor. At the same time, the interaction between the up and down movement of the magnet 231 and the salient poles 121 on the upper and lower sides reduces the number of magnets 231 required for the linear motor to only half the number of salient poles 121, significantly reducing production costs and lightening the weight of the magnet assembly, thereby reducing the motion inertia of the entire movable part.

[0040] As shown in Figures 3, 4, 6 to 11, the linear motor for small household appliances described in this embodiment specifically includes two salient poles 121 spaced apart on the upper and lower inner sidewalls of the iron core 12; two magnets 231 on the magnet assembly; and two windows 211 on both the upper and lower sides of the magnet support 21. This arrangement ensures that the moving parts can reliably move within the housing 11 to achieve state switching of the magnets 231.

[0041] As shown in Figures 3 and 5, in some embodiments of the linear motor for small household appliances described in this embodiment, the switching slot includes a first segment 141, a second segment 142, a third segment 143, and a fourth segment 144 connected end to end; a first step 145 is provided between the first segment 141 and the second segment 142, a second step 146 is provided between the second segment 142 and the third segment 143, and a third step 147 is provided between the third segment 143 and the fourth segment 144; the bottom surfaces of the first segment 141, the second segment 142, and the fourth segment 144 are all inclined surfaces, and the first segment 141 is closer to the fourth segment 144. The depth of one end of the first section 141 is greater than the depth of the end of the second section 142 near the first section 141. The depth of the end of the second section 142 near the first section 141 is less than the depth of the end of the second section 142 near the third section 143. The depth of the end of the fourth section 144 near the third section 143 is less than the depth of the end of the fourth section 144 near the first section 141. The third section 143 is provided with a smooth transition slope 148. The first section 141 and the third section 143 are both straight grooves and are parallel to each other. The second section 142 and the fourth section 144 are both curved grooves. The locking pin 232 is elastically set on the magnet assembly.

[0042] Specifically, initially, the locking pin 232 is located at the end of the first section 141 near the fourth section 144. The magnet 231 is embedded in the upper window 211, corresponding to the upper salient pole 121. The upper coil winding 13 is energized to generate a magnetic field identical to the upper magnetic pole of the magnet 231. Under the action of the magnetic field, the movable part moves to the left, and the locking pin 232 moves along the trajectory of the first section 141 until the locking pin 232 crosses the first step 145 and enters the second section 142. The first step 145 prevents the locking pin 232 from returning to the first section 141. The locking pin 232 moves along the trajectory of the second section 142. At this time, with the cooperation of the locking pin 232 and the second section 142, the magnet assembly moves relative to the magnet support 21 until the locking pin 232 crosses the first step 145. When the second step 146 enters the third section 143, the magnet 231 of the magnet assembly is embedded in the window 211 located on the lower side. When the coil winding 13 located on the lower side is energized to generate a magnetic field with the same magnetic pole as the lower side of the magnet 231, under the action of the magnetic field, the movable part moves to the right, and the locking pin 232 moves along the trajectory of the third section 143. The locking pin 232 crosses the third step 147 and enters the fourth section 144. As the movable part moves to the right, the locking pin 232 moves along the trajectory of the fourth section 144. At this time, with the cooperation of the locking pin 232 and the fourth section 144, the magnet assembly moves relative to the magnet support 21 until the locking pin 232 returns to the initial position, that is, the locking pin 232 is at the junction of the fourth section 144 and the first section 141, thus completing a reciprocating motion cycle.

[0043] This allows the magnet 231 to switch between the upper and lower windows 211. On the one hand, it increases the distance between the magnet 231 and the idle salient pole 121 on the opposite side during the operation of the linear motor, reducing the attraction of the magnet 231 to the idle salient pole 121 and weakening the negative impact of the cogging torque on the output stability. On the other hand, compared to existing linear motors that require more magnets 231 than the iron core 12 salient poles 121, this embodiment requires only half the number of magnets 231, significantly reducing production costs. It also reduces the weight of the moving parts and decreases the motion inertia of the moving parts.

[0044] As shown in Figures 10 and 11, in some embodiments of the linear motor for small household appliances described in this embodiment, the magnet assembly includes a magnet slider 233, with two magnets 231 disposed on the left and right sides of the magnet slider 233. A receiving hole 2331 is provided on the side of the magnet slider 233 near the guide seat 14, and a spring 234 is disposed within the receiving hole 2331. A locking pin 232 is slidably inserted into the receiving hole 2331 and connected to the spring 234. In this embodiment, the magnet slider 233 is provided to facilitate the installation and fixation of the magnets 231; the receiving hole 2331 on the magnet slider 233 facilitates the installation of the spring 234 and the locking pin 232; and the spring 234 ensures that the locking pin 232 maintains its engagement with the switching slot.

[0045] As shown in Figures 6 to 8 and Figures 10 to 12, in some embodiments of the linear motor for small household appliances described in this embodiment, a guide plate 24 is fixedly installed on the side of the magnet support 21 near the guide seat 14. The guide plate 24 has a clearance hole 241 corresponding to the position of the locking pin 232. The guide plate 24 has first guide grooves 242 on both sides of the clearance hole 241, and the outline shape of the first guide grooves 242 is the same as the outline shape of the second section 142 or the fourth section 144. The magnet slider 233 has first guide posts 2332 on both sides of the locking pin 232, and the first guide posts 2332 are movably embedded in the first guide grooves 242. In this embodiment, by providing clearance holes 241, clearance space is provided for the locking pin 232 during operation, and the locking pin 232 is movably embedded in the switching groove after passing through the clearance hole 241. In this embodiment, by setting the first guide groove 242 and the first guide post 2332 in cooperation, the movement of the magnetic slider 233 is guided and limited, so that the magnetic slider 233 drives the magnet 231 to move relative to the magnetic support 21 more stably.

[0046] As shown in Figures 2, 5, 7, and 12, in some embodiments of the linear motor for small household appliances described in this embodiment, the guide plate 24 has second guide posts 243 at both ends; the guide seat 14 has second guide grooves 149 at both ends; and the second guide posts 243 are movably embedded in the second guide grooves 149. This embodiment, by setting the second guide posts 243 and the second guide grooves 149 in cooperation, provides guidance and limitation for the movement of the magnet support 21, making the magnet support 21 more stable during relative movement.

[0047] As shown in Figures 7 and 9 to 11, in some embodiments of the linear motor for small household appliances described in this embodiment, the inner wall of the magnet support 21 is provided with two third guide grooves 212 spaced apart. The outline shape of the third guide grooves 212 is the same as the outline shape of the second section 142 or the fourth section 144. Two third guide posts 2333 are spaced apart on the side of the magnet slider 233 near the opening end of the housing 11. The third guide posts 2333 are movably embedded in the third guide grooves 212. In this embodiment, by setting the third guide posts 2333 to cooperate with the third guide grooves 212, the magnet slider 233 moves more stably and has higher structural reliability under the combined cooperation of the third guide posts 2333, the third guide grooves 212, the first guide posts 2332, and the first guide grooves 242.

[0048] As shown in Figures 1 to 3, in some embodiments of a linear motor for small household appliances, a winding support 15 is provided at both ends of the iron core 12. Preferably, the shape of the winding support 15 is the same as the cross-sectional shape of the iron core 12. In this embodiment, the winding support 15 is provided to facilitate the winding of the coil winding 13.

[0049] As shown in Figures 1 to 3, in some embodiments of the linear motor for small household appliances described in this embodiment, a guide rod 16 is provided at the open end of the housing 11, and the belt head 22 slides through the outer wall of the guide rod 16. In this embodiment, by providing the guide rod 16, the belt head 22 is guided and limited, resulting in higher stability of the entire moving part of the magnet support 21 and belt head 22 under the combined action of the guide rod 16, the second guide post 243, and the second guide groove 149.

[0050] As shown in Figures 2, 6, and 8, in some embodiments of the linear motor for small household appliances described in this embodiment, the lead 22 is slidably mounted on the guide rod 16 via a linear bearing 25. This arrangement facilitates the installation of the guide rod 16 and makes the movement of the lead 22 more stable.

[0051] The above description is only a preferred embodiment of the present invention. Therefore, any equivalent changes or modifications made to the structure, features and principles described in the claims of this patent application are included within the protection scope of this patent application.

Claims

1. A linear motor for small household appliances, characterized in that, The device includes a housing and an iron core housed within the housing. Each of the upper and lower inner walls of the iron core has at least one salient pole, with the salient poles on the upper and lower sides staggered. A coil winding is wound around the salient pole. A guide seat is located at the bottom of the housing. A magnet support is slidably mounted inside the housing. A head is located near the opening of the housing on the magnet support. A magnet assembly is slidably mounted inside the magnet support. The magnet assembly has at least one magnet. At least one window is located on each of the upper and lower sides of the magnet support. The window corresponds to the position of the salient pole. The guide seat is provided with a switching groove, and the magnet assembly is provided with a locking pin. The locking pin is movably embedded in the switching groove so that when the coil winding is energized to generate the same magnetic field as the magnet, the magnet support drives the magnet assembly and the head to slide left and right, while the magnet assembly slides up and down relative to the magnet support, so that the magnet is embedded in the corresponding window.

2. A linear motor for small household appliances according to claim 1, characterized in that, The upper and lower inner walls of the iron core are each provided with two salient poles at intervals; the magnet assembly is provided with two magnets; and the upper and lower sides of the magnet support are each provided with two windows.

3. A linear motor for small household appliances according to claim 2, characterized in that, The switching groove comprises a first section, a second section, a third section, and a fourth section connected end to end. A first step connects the first and second sections, a second step connects the second and third sections, and a third step connects the third and fourth sections. The bottom surfaces of the first, second, and fourth sections are all inclined surfaces. The depth of the first section near the fourth section is greater than the depth of the first section near the second section, the depth of the second section near the first section is less than the depth of the second section near the third section, and the depth of the fourth section near the third section is less than the depth of the fourth section near the first section. A smooth transition slope is provided within the third section. The first and third sections are both straight grooves and are parallel to each other. The second and fourth sections are both curved grooves. The locking pin is elastically set on the magnet assembly.

4. A linear motor for small household appliances according to claim 3, characterized in that, The magnet assembly includes a magnet slider, with two magnets arranged on the left and right sides of the magnet slider. The magnet slider has a receiving hole on the side near the guide seat, and a spring is installed in the receiving hole. A locking pin is slidably inserted into the receiving hole and connected to the spring.

5. A linear motor for small household appliances according to claim 4, characterized in that, A guide plate is provided on the side of the magnet support near the guide seat. The guide plate has a clearance hole corresponding to the position of the locking pin. The guide plate has a first guide groove on both sides of the clearance hole. The outline shape of the first guide groove is the same as the outline shape of the second section or the fourth section. The magnetic slider has first guide posts on both sides of the locking pin, and the first guide posts are movably embedded in the first guide groove.

6. A linear motor for small household appliances according to claim 5, characterized in that, The guide plate has second guide posts at both ends; the guide seat has second guide grooves at both ends; the second guide posts are movably embedded in the second guide grooves.

7. A linear motor for small household appliances according to claim 4, characterized in that, The inner wall of the magnet support is provided with two third guide grooves at intervals, and the outline shape of the third guide grooves is the same as that of the second section or the fourth section; the magnet slider is provided with two third guide posts at intervals on the side near the opening end of the housing; the third guide posts are movably embedded in the third guide grooves.

8. A linear motor for small household appliances according to claim 1, characterized in that, Winding supports are provided at both ends of the iron core.

9. A linear motor for small household appliances according to claim 1, characterized in that, The open end of the housing is equipped with a guide rod, and the head slides through the outer wall of the guide rod.

10. A linear motor for small household appliances according to claim 9, characterized in that, The head is slidably mounted on the guide rod via a linear bearing.

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