Stator core structure of stepping motor

Abstract

The invention relates to the technical field of energy-saving motors, in particular to a stator core structure of a stepping motor. Comprising a stator lamination and a winding coil, inner laminations and outer laminations are sequentially arranged on the two side edges of the stator lamination from inside to outside, inner liquid outlets are formed in the inner laminations and the outer laminations, the inner liquid outlets are communicated with liquid supply parts in the stator lamination, liquid flow guide parts are arranged in the inner liquid outlets, and each liquid flow guide part comprises a temperature sensing part and a guide part. The memory metal sheet has a blocking effect on flowing cooling liquid at high temperature so as to force the cooling liquid to flow into the drainage sheet in an accelerated manner, so that the cooling liquid is discharged from the liquid discharge end and can exchange heat with the coil more effectively, the heat exchange effect is improved, the memory metal sheet applies pressure to the drainage sheet at normal temperature, the liquid discharge end of the drainage sheet is tilted, and the cooling effect is improved. And the elevation angle for spraying the cooling liquid is increased, so that the cooling liquid can be sprayed to the winding coil in a larger coverage range, and the winding coil can be cooled more comprehensively and effectively.

Description

Technical Field

[0001] The present invention relates to the technical field of energy-saving motors, and in particular to a stator core structure of a stepping motor. Background Art

[0002] The stator of a motor running at high power will generate a lot of heat, and it is usually necessary to cool the stator core of the motor and the windings exposed at both ends of the core (also known as end coils in the industry).

[0003] A common method in the prior art is to provide a coolant channel within the core and install an oil spray ring at each end of the core. The oil spray ring has oil spray holes formed in communication with the coolant channel within the core, allowing coolant flowing through the core to be sprayed out of the oil spray holes and onto the end windings. Alternatively, a stator core disclosed in Chinese Patent Publication No. CN118868457A can be used. This stator core comprises a first core unit, a second lamination, and a third lamination. At least one second lamination is provided at each axial end of the first core unit, and at least one third lamination is provided at the end of the second lamination facing away from the first core unit. Multiple first channels are formed within the first core unit. The second lamination has multiple slots, each slot communicating with more than one first channel. The third lamination has multiple axially extending outlet holes, each communicating with a slot. A pair of interconnected slots and outlet holes satisfies the following conditions: the outlet hole is located at the radially innermost region of the slot, and when the stator core is horizontally positioned, for slots extending to the lower semicircular portion of the core, the interconnected outlet holes are located at the highest position of the slot. The stator core can spray coolant to the winding package at the end of the core without using an oil spray ring, so that the winding package can be evenly cooled around the circumference.

[0004] Due to the limited angle of coolant spraying from the outlet channel, the sprayed coolant can only cover the proximal area of ​​the core end winding. For the distal part of the core end winding, the coolant jet attenuates its energy during propagation and has a limited diffusion range, which cannot reach and form effective coverage, resulting in insufficient coolant supply in this area, affecting the cooling effect and increasing overall energy consumption. Summary of the Invention

[0005] The present invention provides a stator core structure for a stepper motor. A memory metal sheet applies pressure to a drain plate at room temperature, causing the drain plate's discharge end to tilt, thereby increasing the elevation angle of the coolant spray. This allows the coolant to be sprayed onto the winding coil with a wider coverage area, thereby solving the problems raised in the above-mentioned background technology, namely: To achieve the above objectives, the stator core structure of the stepper motor includes a stator lamination and a winding coil. The outer ring of the stator lamination is fixed to the housing wall. Inner laminations and outer laminations are arranged on both sides of the stator lamination from the inside to the outside. The inner laminations and outer laminations each have a plurality of internal drain ports for conveying coolant. The internal drain ports are connected to a liquid supply portion provided in the stator lamination, and the liquid supply portion is used to supply coolant to the inner drain ports. A liquid flow guide is provided in each inner drain port located in the outer lamination. The liquid flow guide includes a temperature sensing portion and a guide portion. The temperature sensing portion is used to intercept the coolant at high temperature, forcing the coolant to flow into the guide portion at an accelerated speed to cover the distal coil package. The temperature sensing portion applies pressure to the guide portion to cause the end of the guide portion to tilt, thereby increasing the injection elevation angle to strengthen the coverage of the distal coil package.

[0006] The liquid supply part includes a liquid supply tank opened in the middle of the stator lamination and responsible for storing the cooling liquid. The side of the liquid supply tank is connected with a plurality of liquid supply channels, and the distal ends of the liquid supply channels extend to the side of the stator lamination.

[0007] The temperature sensing part includes a memory metal sheet located in the outer laminate and at the inner wall of the inner drain port. One end of the memory metal sheet is fixed to the inner wall of the inner drain port in the outer laminate, and the other end extends toward the middle. The upper and lower memory metal sheets cooperate to guide the coolant to the middle.

[0008] At room temperature, the memory metal sheet appears hard, and the upper and lower memory metal sheets are V-shaped and in a straight state. At a temperature higher than room temperature, the memory metal sheet appears soft and in a bent state.

[0009] The guide portion includes a drainage plate with one end rotatably connected to the memory metal plate, and the two ends of the drainage plate are respectively formed with a liquid inlet end and a liquid discharge end, and a drainage channel for the coolant to flow is formed by hollowing out between the liquid inlet end and the liquid discharge end; The two side edges of the drainage plate are embedded in the guide grooves provided on the inner wall of the inner drainage port, and the drainage end of the guide groove is tilted upward. When the memory metal sheet changes from a bent state to a straight state, the guide groove can guide the drainage end of the drainage plate to tilt up, thereby increasing the coolant spray elevation angle.

[0010] During cooling: after the coolant comes into contact with the straightened memory metal sheet, the L / 1 line through which the coolant flows is: the coolant flows through the liquid inlet end, the drainage channel, the discharge end in sequence, and is discharged through the raised discharge end. In this way, the elevation angle of the coolant discharged from the raised discharge end is increased, so that the coolant discharged from the discharge end can cover more of the winding wire package surface, thereby increasing the coverage area and reducing the energy consumption of the motor.

[0011] As the memory metal sheet transitions from a straightened state to a bent state, the deformation causes it to drive the drain plate to slide within the guide groove. The guide groove then guides the raised end of the drain plate back toward its straightened position. The coolant's velocity increases as it enters the inlet. As the coolant's velocity increases, so does its kinetic energy. As the coolant flows from the inlet to the outlet, its impact force increases. This increased impact creates a stronger flow effect at the outlet, enabling the coolant to more effectively exchange heat with the coil, improving heat transfer efficiency.

[0012] Compared with the prior art, the present invention has the following beneficial effects: The memory metal sheet creates a barrier to the flowing coolant at high temperatures, forcing the coolant to flow into the drain sheet at an accelerated rate, so that the coolant discharged from the discharge end can more effectively exchange heat with the coil, thereby improving the heat exchange effect. In addition, the memory metal sheet applies pressure to the drain sheet at room temperature, causing the discharge end of the drain sheet to tilt, thereby increasing the elevation angle of the sprayed coolant, allowing the coolant to be sprayed onto the winding coil with a larger coverage area, thereby cooling the winding coil more comprehensively and effectively. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 Schematic diagram of the exploded structure of the stator laminations, inner laminations and outer laminations of the present invention; Figure 3 This is a schematic diagram of the cross-sectional structure of the winding wire package of the present invention; Figure 4 It is a schematic diagram of the structure of the liquid collecting tank and the liquid collecting tank of the present invention; Figure 5 This is a schematic diagram of the coolant flow path of the present invention; Figure 6 For the present invention Figure 5 A in the figure shows the enlarged structural diagram; Figure 7 This is a schematic diagram of the state of the memory metal sheet of the present invention; Figure 8 This is a schematic diagram of the second structural state of the memory metal sheet of the present invention.

[0014] The meaning of each number in the figure is: 100, stator lamination; 110, winding coil; 111, liquid supply tank; 112, liquid supply channel; 113, heat dissipation tank; 114, liquid collection tank; 115, liquid collecting tank; 116, guide tank; 120, inner lamination; 120a, inner drain port; 121, outer lamination; 400, guide groove; 130. Liquid flow guide; 131. Memory metal sheet; 132. Drainage sheet; 133. Drainage channel. DETAILED DESCRIPTION

[0015] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0016] Since the outlet channel is limited in the angle of the coolant sprayed out, the sprayed coolant can only cover the proximal area of ​​the core end coil. For the distal part of the core end coil, the coolant jet has energy attenuation during propagation and a limited diffusion range, and cannot reach and form effective coverage, resulting in insufficient coolant supply in this area, affecting the cooling effect. The present invention provides a stator core structure for a stepper motor, see Figure 1-Figure 4 As shown, the stator lamination 100 and the winding coil 110 are included. The outer ring of the stator lamination 100 is fixed to the inner wall of the housing (not shown in the figure). Inner laminations 120 and outer laminations 121 are arranged on both sides of the stator lamination 100 from the inside to the outside. The inner laminations 120 and the outer laminations 121 are each provided with a plurality of inner drain ports 120a for conveying coolant. The inner drain ports 120a are connected to a liquid supply portion provided in the stator lamination 100, and the liquid supply portion is used to discharge the coolant to the inner drain ports. 120a, wherein the liquid supply portion includes a liquid supply tank 111 opened in the middle of the stator lamination 100 and responsible for storing the coolant. The side of the liquid supply tank 111 is connected to a plurality of liquid supply channels 112. The distal end of the liquid supply channel 112 extends to the side of the stator lamination 100. When the winding package is cooled, the coolant in the liquid supply tank 111 flows to the side of the stator lamination 100 through the plurality of liquid supply channels 112, which can increase the contact area with the heat source, thereby accelerating heat transfer.

[0017] Secondly, in order to improve the heat transfer around the winding package, the outer diameter of the inner lamination 120 and the outer lamination 121 is the same as that of the stator lamination 100, and a heat dissipation groove 113 connected to the liquid supply groove 111 is opened in the axial direction of the outer ring of the stator lamination 100. The outer lamination 121 blocks the end of the heat dissipation groove 113 to limit the outflow of coolant. That is to say, the coolant in the liquid supply groove 111 can not only flow to the liquid supply channel 112, but also flow into the heat dissipation groove 113, and the coolant in the heat dissipation groove 113 transfers its own heat to the corresponding shell, and then transfers it to the external air through the shell, so as to achieve the purpose of heat dissipation.

[0018] In addition, since the wire package is in a fixed state during operation, Figure 4As shown, the coolant flowing out of the coil package flows along the trajectory of the outer ring of the coil package under the action of gravity, while the outer ring below the coil package is repeatedly covered by the coolant. Therefore, a plurality of liquid collecting grooves 114 and liquid collecting grooves 115 are opened on the side of the stator lamination 100. The liquid collecting grooves 114 and the liquid collecting grooves 115 are not arc-shaped and are connected to the corresponding liquid supply channels 112. In this way, the coolant flows from the liquid supply groove 111 through the liquid supply channels 112 into the liquid collecting grooves 114 and the liquid collecting grooves 115. The number of liquid supply channels 112 corresponding to the liquid collecting grooves 115 is less than the number of liquid supply channels 112 corresponding to the liquid collecting grooves 114, that is, the liquid collecting grooves 114 and the liquid collecting grooves 115 are divided by N / 1-N / 2, with the liquid collecting grooves 114 on the upper side and the liquid collecting grooves 115 on the lower side. The coolant accumulated in the liquid collecting grooves 114 is more than the coolant accumulated in the collecting grooves 115, so as to be used for cooling the coil package later. Then, during operation, the upper half of the coil is usually close to the power input terminal or the magnetic circuit concentration area, and needs to withstand higher current density and hysteresis loss, resulting in a higher temperature rise in the upper half than in the lower half. For example, in the stator coil of a motor, the upper half of the coil is close to the air gap, and the magnetic flux density is higher. The combined effect of iron loss and copper loss causes the temperature rise to reach 120°C in the inner lamination, while the lower half is only 105°C; therefore, a guide groove 116 is provided in the middle of the liquid collecting groove 114 and the liquid collecting groove 115. The guide groove 116 extends toward the axis and is connected to the inner drain port 120a in the outer lamination 121 (refer to Figure 6 As shown), the inner drain port 120a is tilted downward and points to the proximal end of the stator lamination 100, based on Figure 4 Based on and combined with Figure 5 、 Figure 6 As shown, the coolant in the liquid supply tank 111 flows to both sides through the liquid supply channel 112 and is collected in the liquid collection tank 114 and the liquid collecting tank 115. When the coolant flows into the guide tank 116, more coolant flows out of the upper liquid collection tank 114 to effectively cool the upper winding coil 110. At the same time, the upper coolant flows along the outer side of the winding coil 110 to the bottom, and can also remove heat from the lower winding coil 110. The coolant flows through the inner drain port 120a in the outer lamination 121 to the inner drain port 120a in the outer lamination 121, and is finally discharged from the outer lamination 121 and the inner drain port 120a, thereby cooling the coil package.

[0019] Next, a liquid flow guide 130 is provided within each inner drain port 120a within the outer lamination 121. The liquid flow guide 130 comprises a temperature-sensing portion and a guide portion. The temperature-sensing portion is used to block the coolant at high temperatures, forcing the coolant to flow into the guide portion at an accelerated rate to cover the distal coil. Simultaneously, the temperature-sensing portion applies pressure to the guide portion, causing the end of the guide portion to tilt upward, increasing the spray elevation angle to enhance coverage of the distal coil. Furthermore, the temperature sensing portion includes a memory metal sheet 131 located at the inner wall of the inner drain port 120a in the outer laminate 121. One end of the memory metal sheet 131 is fixed to the inner wall of the inner drain port 120a in the outer laminate 121, and the other end extends toward the middle. The upper and lower memory metal sheets 131 cooperate to guide the coolant toward the middle. On the other hand, at room temperature, the memory metal sheet 131 exhibits a hard phase, and the upper and lower memory metal sheets 131 are V-shaped and in a straight state. At a temperature higher than room temperature, the memory metal sheet 131 exhibits a soft phase and is in a bent state. Figure 7 、 Figure 8 The memory metal sheet 131 is shown in two states. When the motor is at room temperature (normal operation), the memory metal sheet 131 is Figure 7 In the state shown, when the motor is in a loaded state, the memory metal sheet 131 behaves as Figure 8 Status shown.

[0020] It should be noted that: Figure 7 and Figure 8 The figure shows the decomposition diagram of the coolant flow after the coolant contacts the memory metal sheet 131. The coolant flow is shown in the L / 1 and L / 2 lines. Figure 8 In the figure, a, b, c, d, e, and f represent the bending state, and the contact points between the coolant and the memory metal sheet 131 (i.e., the tangent points of the memory metal sheet 131, which are combined with the coolant flow diagram).

[0021] The following describes the coolant flow to the L / 1 line. The guide portion includes a drainage piece 132, one end of which is rotatably connected to the memory metal sheet 131. The upper and lower ends of the drainage pieces 132 form a liquid inlet end and a liquid discharge end respectively. A drainage channel 133 for the circulation of the coolant is hollowed out between the liquid inlet end and the liquid discharge end. The two side edges of the drainage piece 132 are embedded in the guide groove 121a provided on the inner wall of the inner drain port 120a. The discharge end of the guide groove 121a is tilted upward. When the memory metal sheet 131 changes from a bent state to an extended state, the guide groove 121a can guide the discharge end of the drainage piece 132 to tilt, so as to increase the coolant spray elevation angle, thereby improving the coolant coverage of the winding coil 110.

[0022] Working principle: After the coolant contacts the straightened memory metal sheet 131, the coolant flows through the L / 1 line: the coolant flows through the liquid inlet end, the drainage channel 133, the liquid discharge end, and is discharged through the tilted liquid discharge end. In this way, the elevation angle of the coolant discharged from the tilted liquid discharge end is increased, so that the coolant discharged from the liquid discharge end can cover more of the winding coil 110 surface, thereby increasing the coverage area and reducing motor energy consumption; When the memory metal sheet 131 changes from a straight state to a bent state, the coolant flows through a L / 2 line. Affected by the deformation, the memory metal sheet 131 drives the drainage sheet 132 to slide in the guide groove 121a. The guide groove 121a guides the raised end of the drainage sheet 132 to retract and tend to maintain a straight state. The liquid pressure at the liquid inlet end in the bent state is relative to that in the straight state. When the liquid inlet end is in the bent state, the change in its geometric shape will cause the flow rate of the coolant flowing through this place to increase (the reason is that the memory metal sheet 131 in the bent state has greater resistance to the coolant than the memory metal sheet 131 in the straight state). The flow rate of the coolant is increased when it enters the liquid inlet end. As the flow rate of the coolant increases, the kinetic energy it carries is also increased accordingly. When the coolant flows from the liquid inlet end to the liquid discharge end, its impact force also increases. This increased impact force produces a stronger flow effect at the liquid discharge end, allowing the coolant to exchange heat with the coil more effectively, thereby improving the heat exchange effect.

[0023] In summary, the memory metal sheet 131 has a blocking effect on the flowing coolant at high temperature, forcing the coolant to flow into the drain plate 132 at an accelerated speed, so that the coolant discharged from the discharge end can more effectively exchange heat with the coil, thereby improving the heat exchange effect. In addition, the memory metal sheet 131 applies pressure to the drain plate 132 at normal temperature, causing the discharge end of the drain plate 132 to tilt, thereby increasing the elevation angle of the sprayed coolant, so that the coolant can be sprayed onto the winding coil 110 with a larger coverage area, thereby more comprehensively and effectively cooling the winding coil 110.

[0024] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely preferred examples of the present invention and are not intended to limit the present invention. Various changes and improvements may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and improvements fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. A stator core structure of a stepper motor, comprising a stator lamination (100) and a winding coil (110), wherein the outer ring of the stator lamination (100) is fixed to a housing wall, and is characterized in that: Inner laminations (120) and outer laminations (121) are sequentially arranged on both sides of the stator laminations (100) from the inside to the outside, and the inner laminations (120) and the outer laminations (121) are each provided with a plurality of inner drain ports (120a) for conveying cooling liquid, and the inner drain ports (120a) are in communication with a liquid supply portion provided in the stator laminations (100), and the liquid supply portion is used to supply cooling liquid into the inner drain ports (120a); A liquid flow guide portion (130) is provided in each inner liquid discharge port (120a) located in the outer lamination (121). The liquid flow guide portion (130) includes a temperature sensing portion and a guide portion. The temperature sensing portion is used to block the coolant at high temperature, forcing the coolant to flow into the guide portion at an accelerated speed to cover the distal coil. The temperature sensing portion applies pressure to the guide portion, causing the end of the guide portion to tilt, thereby increasing the injection elevation angle to strengthen the coverage of the distal coil.

2. The stator core structure of the stepping motor according to claim 1, wherein: The liquid supply portion includes a liquid supply tank (111) opened in the middle of the stator lamination (100) and responsible for storing the cooling liquid. The side of the liquid supply tank (111) is connected to a plurality of liquid supply channels (112), and the distal ends of the liquid supply channels (112) extend to the side of the stator lamination (100).

3. The stator core structure of the stepping motor according to claim 2, wherein: The outer diameters of the inner laminations (120) and the outer laminations (121) are the same as those of the stator laminations (100). A heat dissipation groove (113) connected to the liquid supply groove (111) is provided in the axial direction of the outer ring of the stator laminations (100). The outer laminations (121) block the end of the heat dissipation groove (113) to limit the outflow of coolant.

4. The stator core structure of the stepping motor according to claim 2, wherein: A plurality of liquid collecting grooves (114) and liquid collecting grooves (115) are provided on the side of the stator lamination (100), wherein the liquid collecting grooves (114) and the liquid collecting grooves (115) are not arc-shaped and are connected to the corresponding liquid supply channels (112), and the number of the liquid supply channels (112) corresponding to the liquid collecting grooves (115) is less than the number of the liquid supply channels (112) corresponding to the liquid collecting grooves (114).

5. The stator core structure of the stepping motor according to claim 4, characterized in that: A guide groove (116) is provided in the middle of each of the liquid collecting groove (114) and the liquid collecting groove (115). The guide groove (116) extends toward the axis and is connected to an inner drain port (120a) in the outer lamination (121). The inner drain port (120a) is downwardly inclined and points to the proximal end of the stator lamination (100).

6. The stator core structure of the stepping motor according to claim 1, wherein: The temperature sensing portion includes a memory metal sheet (131) located at the inner wall of the inner liquid discharge port (120a) in the outer laminate (121), one end of the memory metal sheet (131) is fixed to the inner wall of the inner liquid discharge port (120a) in the outer laminate (121), and the other end extends toward the middle. The upper and lower memory metal sheets (131) cooperate to guide the cooling liquid toward the middle.

7. The stator core structure of the stepping motor according to claim 6, characterized in that: At room temperature, the memory metal sheet (131) exhibits a hard phase, and the upper and lower memory metal sheets (131) are V-shaped and in a straight state. At a temperature higher than room temperature, the memory metal sheet (131) exhibits a soft phase and is in a bent state.

8. The stator core structure of the stepping motor according to claim 7, characterized in that: The guide portion includes a drainage piece (132) rotatably connected to the memory metal piece (131) at one end, a liquid inlet end and a liquid discharge end formed at the upper and lower ends of the drainage piece (132), and a drainage channel (133) for the circulation of the coolant is hollowed out between the liquid inlet end and the liquid discharge end; Both sides of the drainage piece (132) are embedded in the guide grooves (121a) provided on the inner wall of the inner drainage port (120a), and the drainage end of the guide groove (121a) is tilted upward, so that when the memory metal piece (131) changes from a bent state to a straight state, the guide groove (121a) can guide the drainage end of the drainage piece (132) to tilt up, thereby increasing the cooling liquid spray elevation angle.

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