A linear motor for small household appliances

Abstract

The invention discloses a linear motor for small household appliances, comprising a casing and an iron core, wherein the upper and lower inner 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 staggered with each other; a coil winding is wound around the salient pole, a guide seat is provided at the inner bottom of the casing, a magnet support is slidably provided in the casing, a lead is provided at a position of the magnet support close to an opening end of the casing, and a magnet assembly is slidably provided in the magnet support; the magnet assembly is provided with at least one magnet; at least one window is provided on 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 bayonet, which 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 lead to slide left and right, and at the same time the magnet assembly slides up and down relative to the magnet support, so that the magnet is embedded in the corresponding window; the output smoothness of the linear motor is improved, the production cost is reduced, and the movement inertia of the entire active part is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of motors, and in particular to a linear motor for small household appliances. Background Art

[0002] Linear motors for small household appliances are mostly permanent magnet synchronous motors due to size and cost factors. Due to the attraction of the magnetic steel to the stator core, there is a cogging torque, which makes the output torque provided by the linear motor during operation have periodic fluctuations that are the same as the number of magnetic pole pairs. This periodic fluctuation makes it impossible for the rotor of the linear motor to provide sufficiently linear and smooth output torque, reducing the user experience. Summary of the invention

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

[0004] To achieve the above-mentioned purpose, the specific scheme of the present invention is as follows: a linear motor for small household appliances, comprising a casing, an iron core arranged in the casing, the 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 staggered; a coil winding is wound around the salient pole, a guide seat is provided at the inner bottom of the casing, a magnet support is slidably arranged in the casing, a lead is provided at a position of the magnet support near the opening end of the casing, and a magnet assembly is slidably arranged in the magnet support; the magnet assembly is provided with at least one magnet; at least one window is provided on 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 bayonet, which is movably embedded in the switching groove. When the coil winding is energized to generate the same magnetic field as the magnet, the magnet support drives the magnet assembly and the lead to slide left and right, and at the same time, the magnet assembly slides up and down relative to the magnet support, so that the magnet is embedded in the corresponding window.

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

[0007] Optionally, the switching groove comprises a first section, a second section, a third section and a fourth section which are connected end to end in sequence; 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 end of the first section close to the fourth section is greater than the depth of the end of the first section close to the second section, the depth of the end of the second section close to the first section is less than the depth of the end of the second section close to the third section, and the depth of the end of the fourth section close to the third section is less than the depth of the end of the fourth section close to 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 bayonet is elastically arranged on the magnet assembly.

[0009] Optionally, the magnet assembly includes a magnet slider, two magnets are arranged on the left and right sides of the magnet slider, a receiving hole is provided on the side of the magnet slider close to the guide seat, a spring is provided in the receiving hole, and the pin is slidably inserted into the receiving hole and connected to the spring.

[0010] Optionally, a guide plate is provided on one side of the magnet support close to the guide seat, an avoidance hole is provided on the guide plate at a position corresponding to the bayonet, and a first guide groove is provided on both sides of the avoidance hole, and the contour shape of the first guide groove is the same as the contour shape of the second section or the fourth section;

[0011] The magnet sliding block is provided with first guide posts on both sides of the bayonet, and the first guide posts are movably embedded in the first guide grooves.

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

[0013] Optionally, two third guide grooves are provided at intervals on the inner wall of the magnet support, and the contour shape of the third guide grooves is the same as the contour shape of the second section or the fourth section; two third guide columns are provided at intervals on one side of the magnet slider close to the opening end of the casing; and the third guide column is movably embedded in the third guide groove.

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

[0015] Optionally, a guide rod is provided at the open end of the housing, and the belt head is slidably inserted into the outer wall of the guide rod.

[0016] Optionally, the belt head is slidably sleeved on the guide rod through a linear bearing.

[0017] The beneficial effects of the present invention are as follows: the present invention sets the magnetic steel in an active state, and uses the cooperation of the bayonet pin and the switching slot to make the magnetic steel switch between the windows on the upper and lower sides of the magnet support, so that during the operation of the linear motor, the distance between the magnetic steel and the salient poles corresponding to the non-energized coil winding is increased, thereby reducing the influence of the tooth slot torque on the output torque of the linear motor and improving the output smoothness of the linear motor; at the same time, the up and down movement of the magnetic steel interacts with the salient poles on the upper and lower sides, so that the number of magnetic steels required for the linear motor is only half of the number of salient poles, which significantly reduces the production cost, and at the same time reduces the weight of the magnet assembly, thereby reducing the movement inertia of the entire active part. BRIEF DESCRIPTION OF THE DRAWINGS

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

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

[0020] Figure 3 is a stereogram of the fixed 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 three-dimensional diagram of the guide seat of the present invention;

[0023] Figure 6 It is a three-dimensional diagram of the movable part of the present invention when the magnetic steel is embedded in the upper window;

[0024] Figure 7 It is a stereogram of the movable part of the present invention from another perspective when the magnetic steel is embedded in the upper window;

[0025] Figure 8 It is a three-dimensional diagram of the movable part of the present invention when the magnetic steel is embedded in the lower side window;

[0026] Fig. 9 It is a structural schematic diagram of the magnet support of the present invention;

[0027] Fig.10 is a stereogram of a magnet assembly of the present invention;

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

[0029] Fig.12 It is a structural schematic diagram of the guide plate of the present invention;

[0030] Explanation of the reference numerals: 11, housing; 12, 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 bracket; 16, guide rod; 21, magnet support; 211, window; 212, third guide groove; 22, lead; 231, magnet; 232, latch; 233, magnet slider; 2331, accommodating hole; 2332, first guide column; 2333, third guide column; 234, spring; 24, guide plate; 241, avoidance hole; 242, first guide groove; 243, second guide column; 25, linear bearing. DETAILED DESCRIPTION

[0031] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments, but the implementation scope of the present invention is not limited thereto.

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

[0033] It also includes an iron core 12 arranged in the installation space of the casing 11, and the upper and lower inner side walls of the iron core 12 are each provided with at least one salient pole 121, and the salient poles 121 on the upper and lower sides are staggered; preferably, the projections of the salient poles 121 on the central cross section of the iron core 12 are partially overlapped; a coil winding 13 is wound around each salient pole 121, a guide seat 14 is provided on the inner bottom of the casing 11, a magnet support 21 is slidably provided in the casing 11, a lead 22 is provided at a position of the magnet support 21 close to the opening end of the casing 11, and a magnet assembly is slidably provided in the magnet support 21; the magnet assembly is provided with at least one magnetic steel 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 salient pole 121;

[0034] The guide seat 14 is provided with a switching groove, and the magnet assembly is provided with a latch 232, which is movably embedded in the switching groove. 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 lead 22 to slide left and right, and at the same time, 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, the iron core 12, the coil winding 13, and the guide seat 14 constitute the fixed part; the magnet support 21, the belt head 22, and the magnet assembly constitute the movable part.

[0036] Specifically, the linear motor of this embodiment, such as Figure 6 As shown, initially, the latch 232 cooperates 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 salient pole 121 located on the upper side.

[0037] When the coil winding 13 on the upper side 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 force of the magnetic field. At this time, under the cooperation of the switching slot and the latch 232, the magnet support 21 slides to the left and drives the belt 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 released from the upper window 211 until the magnet 231 on the magnet assembly is embedded in the lower window 211. Figure 8 As shown, the lower side of the magnetic steel 231 is opposite to the salient pole 121 below, so that the distance between the magnetic steel 231 and the salient pole 121 corresponding to the upper non-energized coil winding 13 is increased, thereby completing the state switching of the magnet assembly;

[0038] After the state switching is completed, the coil winding 13 located at the lower side is energized to generate a magnetic field identical to the magnetic pole at the lower side of the magnet 231, pushing the magnet assembly to slide upward. At this time, the magnet support 21 drives the lead 22 to move to the right, and 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 window 211 located at the upper side. Figure 6 and Figure 7 As shown, the upper side of the magnetic steel 231 is positioned opposite to the salient pole 121 located on the upper side, thereby returning to the initial position, so that the distance between the magnetic steel 231 and the salient pole 121 corresponding to the non-powered coil winding 13 located on the lower side is increased, thus completing a reciprocating motion cycle.

[0039] In this embodiment, the magnet 231 is set to an active state, and the latch 232 cooperates with the switching slot to enable the magnet 231 to switch between the windows 211 on the upper and lower sides of the magnet support 21. Therefore, during the operation of the linear motor, the distance between the magnet 231 and the salient poles 121 corresponding to the non-energized coil winding 13 is increased, thereby reducing the influence of the cogging torque on the output torque of the linear motor and improving the output smoothness of the linear motor. At the same time, the up and down movement of the magnet 231 interacts with the salient poles 121 on the upper and lower sides, so that the number of magnets 231 required for the linear motor is only half of the number of salient poles 121, which significantly reduces the production cost and reduces the weight of the magnet assembly, thereby reducing the movement inertia of the entire active part.

[0040] like Figure 3 , Figure 4 , Figures 6 to 11 As shown, the linear motor for small household appliances described in this embodiment, specifically, the upper and lower inner walls of the iron core 12 are each provided with two salient poles 121; the magnet assembly is provided with two magnets 231; and the upper and lower sides of the magnet support 21 are each provided with two windows 211. Such an arrangement enables the movable part to reliably move in the housing 11 to realize the state switching of the magnet 231.

[0041] like Figure 3 and Figure 5 As shown, in the linear motor for small household appliances described in this embodiment, in some embodiments, the switching slot includes a first section 141, a second section 142, a third section 143 and a fourth section 144 which are connected end to end in sequence; a first step 145 is provided between the first section 141 and the second section 142, a second step 146 is provided between the second section 142 and the third section 143, and a third step 147 is provided between the third section 143 and the fourth section 144; the bottom surfaces of the first section 141, the second section 142 and the fourth section 144 are all inclined surfaces, and one end of the first section 141 close to the fourth section 144 The depth of the first section 141 is greater than the depth of one end of the second section 142 close to the first section 141, the depth of one end of the second section 142 close to the first section 141 is less than the depth of one end of the second section 142 close to the third section 143, and the depth of one end of the fourth section 144 close to the third section 143 is less than the depth of one end of the fourth section 144 close to the first section 141; a smooth transition inclined surface 148 is provided in the third section 143; 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 bayonet 232 is elastically arranged on the magnet assembly.

[0042] Specifically, at the beginning, the latch 232 is located at one end of the first section 141 close to the fourth section 144, the magnetic steel 231 is embedded in the window 211 on the upper side, and corresponds to the position of the salient pole 121 on the upper side. The coil winding 13 on the upper side is energized to generate a magnetic field identical to the magnetic pole on the upper side of the magnetic steel 231. Under the force of the magnetic field, the movable part moves to the left, and the latch 232 moves along the trajectory of the first section 141 until the latch 232 passes over the first step 145 and enters the second section 142. The first step 145 blocks the latch 232 from returning to the first section 141, and the latch 232 moves along the trajectory of the second section 142. At this time, with the cooperation of the latch 232 and the second section 142, the magnet assembly moves relative to the magnet support 21 until the latch 232 passes over 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 at the lower side; when the coil winding 13 located at the lower side is energized to generate a magnetic field identical to the magnetic pole at the lower side of the magnet 231, the movable part moves to the right under the force of the magnetic field, and the latch 232 moves along the track of the third section 143. The latch 232 passes over the third step 147 and enters the fourth section 144. As the movable part moves to the right, the latch 232 moves along the track of the fourth section 144. At this time, under the cooperation of the latch 232 and the fourth section 144, the magnet assembly moves relative to the magnet support 21 until the latch 232 returns to the initial position, that is, the latch 232 is at the junction of the fourth section 144 and the first section 141, thereby completing a reciprocating motion cycle;

[0043] In this way, the magnet 231 can switch between the windows 211 on the upper and lower sides. On the one hand, the magnet 231 is farther away from the idle salient pole 121 on the opposite side during the operation of the linear motor, which reduces the attraction of the magnet 231 to the idle salient pole 121 and weakens the negative impact of the cogging torque on the output stability. On the other hand, compared with the existing linear motor that requires a magnet 231 whose number is greater than the number of salient poles 121 of the iron core 12, the number of magnets 231 required in this embodiment is only half of the number of salient poles 121 of the iron core 12, which significantly reduces the production cost, while also reducing the weight of the moving part and reducing the movement inertia of the moving part.

[0044] like Fig.10 and Fig.11As shown, in some embodiments of the linear motor for small household appliances described in this embodiment, the magnet assembly includes a magnet slider 233, two magnets 231 are arranged on the left and right sides of the magnet slider 233, and a receiving hole 2331 is provided on the side of the magnet slider 233 close to the guide seat 14, and a spring 234 is arranged in the receiving hole 2331, and a bayonet 232 is slidably inserted into the receiving hole 2331 and connected with the spring 234. In this embodiment, the magnet slider 233 is provided to facilitate the installation and fixation of the magnet 231; the receiving hole 2331 is provided on the magnet slider 233 to facilitate the installation of the spring 234 and the bayonet 232, and the spring 234 is provided to enable the bayonet 232 to maintain the matching with the switching slot.

[0045] like Figures 6 to 8 , Figures 10 to 12 As shown, in some embodiments of the linear motor for small household appliances described in this embodiment, a guide plate 24 is fixedly installed on one side of the magnet support 21 close to the guide seat 14, and a avoidance hole 241 is provided on the guide plate 24 corresponding to the position of the bayonet 232, and a first guide groove 242 is provided on both sides of the avoidance hole 241 of the guide plate 24, and the contour shape of the first guide groove 242 is the same as the contour shape of the second section 142 or the fourth section 144; the magnet slider 233 is provided with a first guide column 2332 on both sides of the bayonet 232, and the first guide column 2332 is movably embedded in the first guide groove 242. In this embodiment, the avoidance hole 241 is provided to provide an avoidance space for the bayonet 232 during operation, and the bayonet 232 is movably embedded in the switching groove after passing through the avoidance hole 241. In this embodiment, the first guide groove 242 cooperates with the first guide column 2332 to provide guidance and limit for the movement of the magnet slider 233, so that the magnet slider 233 drives the magnet steel 231 to move relative to the magnet support 21 more stably.

[0046] like Figure 2 , Figure 5 , Figure 7 and Fig.12 As shown, in the linear motor for small household appliances described in this embodiment, in some embodiments, second guide posts 243 are provided at both ends of the guide plate 24; second guide grooves 149 are provided at both ends of the guide seat 14; and the second guide posts 243 are movably embedded in the second guide grooves 149. In this embodiment, the second guide posts 243 and the second guide grooves 149 are provided to cooperate, thereby providing guidance and limiting for the movement of the magnet support 21, so that the magnet support 21 is more stable during relative movement.

[0047] like Figure 7 , Figures 9 to 11As shown, in some embodiments of the linear motor for small household appliances described in this embodiment, two third guide grooves 212 are provided at intervals on the inner wall of the magnet support 21, and the contour shape of the third guide groove 212 is the same as the contour shape of the second section 142 or the fourth section 144; two third guide posts 2333 are provided at intervals on one side of the magnet slider 233 close to the opening end of the housing 11; and the third guide post 2333 is movably embedded in the third guide groove 212. In this embodiment, the third guide post 2333 is provided to cooperate with the third guide groove 212, so that the magnet slider 233 moves more stably and has higher structural reliability under the cooperation of the third guide post 2333, the third guide groove 212, the first guide post 2332, and the first guide groove 242.

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

[0049] like Figures 1 to 3 As shown, in the linear motor for small household appliances described in this embodiment, in some embodiments, a guide rod 16 is provided at the open end of the housing 11, and the belt head 22 is slidably penetrated on the outer wall of the guide rod 16. In this embodiment, the guide rod 16 is provided to provide guidance and limit for the belt head 22, so that the magnet support 21 and the belt head 22 have higher movement stability under the joint action of the guide rod 16, the second guide column 243 and the second guide groove 149.

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

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

Claims

1. A linear motor for small household appliances, characterized in that: The invention comprises a casing, an iron core arranged in the casing, at least one salient pole is arranged on the upper and lower inner side walls of the iron core, and the salient poles on the upper and lower sides are staggered; a coil winding is wound around the salient pole, a guide seat is arranged on the inner bottom of the casing, a magnet support is slidably arranged in the casing, a lead is arranged at a position of the magnet support near the opening end of the casing, and a magnet assembly is slidably arranged in the magnet support; the magnet assembly is provided with at least one magnet; at least one window is arranged on 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 slot, and the magnet assembly is provided with a bayonet, which is movably embedded in the switching slot, so that when the coil winding is energized to generate the same magnetic field as the magnetic steel, the magnet support drives the magnet assembly and the belt head to slide left and right, and at the same time, the magnet assembly slides up and down relative to the magnet support, so that the magnetic steel is embedded in the corresponding window; The switching groove comprises a first section, a second section, a third section and a fourth section which are connected end to end in sequence; 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 end of the first section close to the fourth section is greater than the depth of the end of the first section close to the second section, the depth of the end of the second section close to the first section is less than the depth of the end of the second section close to the third section, and the depth of the end of the fourth section close to the third section is less than the depth of the end of the fourth section close to 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; The bayonet is elastically arranged on the magnet assembly.

2. A linear motor for small household appliances according to claim 1, characterized in that: The upper and lower inner side walls of the iron core are each provided with two salient poles at intervals; the magnet assembly is provided with two magnetic steels; 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 magnet assembly includes a magnet slider, two magnets are arranged on the left and right sides of the magnet slider, a receiving hole is provided on the side of the magnet slider close to the guide seat, a spring is arranged in the receiving hole, and the bayonet is slidably inserted into the receiving hole and connected to the spring.

4. A linear motor for small household appliances according to claim 3, characterized in that: A guide plate is provided on one side of the magnet support close to the guide seat, an avoidance hole is provided at a position of the guide plate corresponding to the bayonet, and a first guide groove is provided on both sides of the avoidance hole, and the contour shape of the first guide groove is the same as the contour shape of the second section or the fourth section; The magnet sliding block is provided with first guide posts on both sides of the bayonet, and the first guide posts are movably embedded in the first guide grooves.

5. A linear motor for small household appliances according to claim 4, characterized in that: The two ends of the guide plate are provided with second guide posts; the two ends of the guide seat are provided with second guide grooves; the second guide posts are movably embedded in the second guide grooves.

6. A linear motor for small household appliances according to claim 3, characterized in that: Two third guide grooves are arranged at intervals on the inner wall of the magnet support, and the contour shape of the third guide grooves is the same as the contour shape of the second section or the fourth section; two third guide posts are arranged at intervals on one side of the magnet slider close to the opening end of the casing; the third guide post is movably embedded in the third guide groove.

7. 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.

8. The linear motor for small household appliances according to claim 1, characterized in that: A guide rod is arranged at the opening end of the casing, and the belt head is slidably penetrated on the outer wall of the guide rod.

9. A linear motor for small household appliances according to claim 8, characterized in that: The lead head is slidably sleeved on the guide rod through a linear bearing.

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