Fastening device for aligning and pressing motor core laminate member

Abstract

The present invention provides a fastening device for aligning and pressing a motor core laminate member, which can fix, align, and simultaneously press a non-oriented electrical steel sheet punching laminate member for a motor core. Disclosed is a fastening device for aligning and pressing a motor core laminate member, which comprises: a collet in which an outer diameter of a lower portion matches an inner diameter of a motor core laminate member coupled to a circumference, and an outer diameter of an upper portion is formed to be larger than the inner diameter of the motor core laminate member; and a hollow shaft coupled to a hollow portion of the collet, wherein when the motor core laminate member is coupled to the collet, an upper portion of the contracted collet is elastically supported on an inner circumferential surface of the motor core laminate.

Description

Fastening device for alignment and pressure of motor core laminate members

[0001] The present invention relates to a fastening device for aligning and pressing a motor core laminate member, and more specifically, to a fastening device for aligning and pressing a motor core laminate member that can fix, align, and simultaneously press a non-oriented electrical steel sheet punched laminate for a motor core.

[0002] As the popularization of electric vehicles progresses rapidly, the performance of drive motors, a core component, is being enhanced, and technological development is underway to improve magnetic, mechanical, and heat generation characteristics.

[0003] Motor cores for electric vehicle drive motors are manufactured by simultaneously stamping and laminating thin non-oriented electrical steel sheets from strips, or by performing lamination only and then joining the laminated sheets into a single block.

[0004] Conventional fastening methods involved mechanical joining utilizing irregularities formed within stamped steel sheets or welding the outer surface of the laminate in the lamination direction; however, the application of bonding methods using structural adhesives has recently been expanding. This is because motor cores produced by bonding methods offer superior magnetic properties compared to conventional fastening methods, as well as advantages such as reduced noise and vibration and rapid heat conduction. In this case, if the adhesive is a thermosetting resin, the laminate must be heated to the temperature required for curing while applying pressure perpendicular to the bonding surface.

[0005] Conventional heating methods are convection or induction heating using hot air, and among these, in the case of convection heating, a lamp for near-infrared radiation heating may be added as an auxiliary heat source.

[0006] At this time, since the core laminate is located within a thick metal fastening device (Jig) for alignment and pressure maintenance, it is difficult to install a heat source on the inner side of the core in the case of the aforementioned convection, radiation, and induction heating, so when heating the core, the temperature on the outer surface side is always relatively high, resulting in a steep temperature difference between the outer and inner surfaces.

[0007] These temperature deviations tend to increase as the heating rate increases. Since the thin insulation and adhesive layers between each stamped steel layer within the laminate suppress heat diffusion into the motor core, the temperature deviation problem is further exacerbated, becoming a factor that consequently causes variation in interlayer adhesion strength.

[0008] Meanwhile, the axial pressure required for the bonding process can be applied by an elastic member, such as a spring, installed on the upper or lower surface of the motor core laminate, or by a pressure source, such as a pneumatic actuator. Typically, it can be applied by pressure springs arranged at equal intervals along the circumferential direction of the laminate.

[0009] However, even if the pressure springs are installed evenly along the circumferential direction, there are cases where the pressure distribution in reality is uneven due to the following reasons, causing a dispersion of adhesive strength.

[0010] First, if the radial direction of the motor core is misaligned with the pressure spring seat, uneven loading occurs on the teeth or yoke side of the stator core. This generates bending moments and consequent bending stresses in the laminate, weakening or offsetting the pressure in the lamination direction in the outer bending region, or conversely, causing excessive pressure in the inner bending region, which can lead to damage to the insulation layer or leakage of the adhesive at high temperatures.

[0011] Second, when pressurized, the deflection of each component forming the fastening device due to the eccentricity of the axial reaction force of the motor core within the fastening device distorts the shape of the pressure plate.

[0012] Meanwhile, ensuring that this pressure propagates axially through the laminated body and is effectively transmitted to the opposite side of the pressure surface (corresponding to the bottom surface when the pressure part is the top surface) is also an important factor in terms of pressure equalization.

[0013] For example, when the pressure surface is on the upper side of the laminate, the radial contact pressure and axial friction force generated by friction between the expansion mandrel, which contacts the inner surface (teeth end) of the motor core laminate for axial alignment, partially offset the axial pressure, which can cause a loss of pressure on the lower side of the laminate.

[0014] Here, the expansion mandrel is a component that typically expands the outer surface of a collet by axially pressing a tapered shaft (or arbor) into the inner surface of the collet, and is responsible for aligning the laminate axially by radially pressing the inner surface of the motor core.

[0015] (Prior Art Literature)

[0016] (Patent Document 1) Korean Patent Publication No. 10-2021-0130670

[0017] (Patent Document 2) Korean Patent Publication No. 10-2020-0076495

[0018] (Patent Document 3) Korean Patent Publication No. 10-2020-0133479

[0019] According to one embodiment of the present invention, a fastening device for alignment and pressing of a motor core laminate member can be provided, which improves the distribution of pressure in the lamination direction during pressing and heating for bonding of a non-oriented electrical steel sheet motor core laminate member, and reduces the temperature difference between the outer periphery and the inner periphery of the motor core during the heating and cooling process of the motor core.

[0020] The problems of the present invention are not limited to those described above. A person skilled in the art to which the present invention pertains will have no difficulty understanding additional problems of the present invention from the overall contents of this specification.

[0021] A fastening device for aligning and pressing a motor core laminate member according to one embodiment of the present invention comprises: a collet having a lower outer diameter that matches the inner diameter of a motor core laminate member coupled to the circumference, and an upper outer diameter that is larger than the inner diameter of the motor core laminate member; and a hollow shaft coupled to the hollow portion of the collet; wherein, when the motor core laminate member is coupled to the collet, the upper portion of the contracted collet is elastically supported on the inner circumference of the motor core laminate member.

[0022] In one embodiment of the present invention, the collet may be formed such that the wall portion has a plurality of slots with the top open.

[0023] In one embodiment of the present invention, the collet may include: a base portion at the bottom; a plurality of support portions extending vertically from the base portion with the slot in between; and an inclined portion extending inwardly at an angle from the top of the support portion.

[0024] In one embodiment of the present invention, a collet pressing member may be included, which is coupled to the upper part of the hollow shaft and has an inner surface formed as a protrusion protruding downward to press the inclined portion downward.

[0025] In one embodiment of the present invention, an upper pressure plate and a lower pressure plate may be included, respectively, positioned to be in close contact with the upper and lower ends of a motor core laminate member coupled to the collet.

[0026] In one embodiment of the present invention, it may include a lower base plate disposed on the lower side of the lower pressure plate; and a plurality of pins disposed to support between the lower pressure plate and the lower base plate.

[0027] In one embodiment of the present invention, the pin may be inserted into a first insertion groove formed on the lower surface of the lower pressure plate and a second insertion groove formed on the upper surface of the lower base plate with a gap between them.

[0028] In one embodiment of the present invention, an upper cover plate may be included that is elastically supported on the upper side of the upper pressure plate.

[0029] In one embodiment of the present invention, a spring may be included that is positioned between the upper pressure plate and the upper cover plate to support the upper cover plate.

[0030] In one embodiment of the present invention, the position (r) of the spring optLoad ) can be set by the following equation.

[0031] ,

[0032] ,

[0033] x= , provided that among the two years r optLoad A solution x is selected that does not exceed the dimensions of the above motor core laminate member, and

[0034] r optLoad = r teeth + b + x

[0035] Here, S core is the area of ​​the pressurized surface of the motor core laminate member, and Stotal is the area of ​​the stacked ring, and S slot is the area of ​​the slot, and S teeth is the area of ​​the tooth portion, and S yoke is the area of ​​the yoke, and l min is the length of the circumference of the inner face of the laminate, and l max is the length of the circumference of the outer surface of the laminate, and l slot is the length of the circumference at the boundary between the yoke and the tooth, and w is r yoke -r teeth is, r yoke is the radius of the laminate, and r teeth is the radius from the center of the laminate to the tip of the tooth, b is the length of the slot along the radial direction, and x is r in the radial direction from the center of the laminate. teeth As the slope of increase in the circumferential length of the yoke portion with respect to the radius position from the point at + b to the outer surface of the laminate (l max - l slot ) / (wb)is.

[0036] The fastening device for alignment and pressure application of a motor core laminate member according to the present invention has the effect of improving the distribution of pressure in the lamination direction during pressure and heating for bonding a non-oriented electrical steel sheet motor core laminate member, and reducing the temperature difference between the outer periphery and the inner periphery of the motor core during the heating and cooling process of the motor core.

[0037] FIG. 1 is a perspective view illustrating a fastening device for alignment and pressure application of a motor core laminate member according to one embodiment of the present invention.

[0038] Figure 2 is a cross-sectional view along line AB of Figure 1.

[0039] FIG. 3 is a translucent perspective view illustrating the collet pressing member of FIG. 2.

[0040] Fig. 4 is a perspective view illustrating the collet of Fig. 2.

[0041] Fig. 5 is a perspective view illustrating the hollow shaft of Fig. 2.

[0042] FIG. 6 is a perspective view illustrating a motor core laminate member to which an embodiment of the present invention is applied.

[0043] FIG. 7 is a front view illustrating a top plate, an upper pressure plate, a motor core laminate member, a lower pressure plate, and a lower base plate.

[0044] Figure 8 is a plan view of the top plate for finding the optimized load point of the spring.

[0045] Figure 9 is a plan view illustrating the relationship between a spring and a pin.

[0046] FIGS. 10 and 11 show the contact pressure distribution formed on the upper surface of the motor core laminate member in the comparative example and the embodiment.

[0047] FIGS. 12 and 13 show the contact pressure distribution formed on the lower surface of the motor core laminate member in the comparative example and the embodiment.

[0048] FIGS. 14 to 19 show graphs and test results for comparing the contact pressure distribution of a motor core of a comparative example and a motor core according to an embodiment.

[0049] Preferred embodiments of the present invention will be described below with reference to the attached drawings. However, embodiments of the present invention may be modified in various other forms, and the scope of the present invention is not limited to the embodiments described below.

[0050] In addition, embodiments of the present invention are provided to more fully explain the present invention to those with average knowledge in the relevant technical field.

[0051] In drawings, the shapes and sizes of elements may be exaggerated for clearer explanation.

[0052] In describing the embodiments of the present invention, if it is determined that a detailed description of known technology related to the present invention may unnecessarily obscure the essence of the present invention, such detailed description will be omitted. Furthermore, the terms described below are defined considering their functions in the present invention, and these may vary depending on the intentions or conventions of the user or operator. Therefore, such definitions should be based on the content throughout this specification. The terms used in the detailed description are merely for describing the embodiments of the present invention and should not be limited in any way. Unless explicitly stated otherwise, expressions in the singular form include the meaning of the plural form.

[0053] In this description, expressions such as “include” or “equipped” are intended to refer to certain characteristics, numbers, steps, actions, elements, parts or combinations thereof, and should not be interpreted to exclude the existence or possibility of one or more other characteristics, numbers, steps, actions, elements, parts or combinations thereof other than those described.

[0054] In this specification, terms such as 'top', 'upper', 'upper surface', 'lower', 'lower surface', 'lower surface', and 'side surface' are based on the drawings and may actually vary depending on the direction in which the elements or components are arranged.

[0055] Additionally, throughout the specification, when it is said that one part is 'connected' to another part, this includes not only cases where they are 'directly connected,' but also cases where they are 'indirectly connected' with other elements in between.

[0056] The present invention will be described in detail below through each embodiment or example of the invention. It should be noted that each embodiment or example described in this specification is not limited to just one embodiment or example, but may also be combined with other embodiments or examples.

[0057] Therefore, the citation of claims in the patent claims is merely an example of an embodiment, and the technical concept of the present invention should not be interpreted as being limited to a combination with the cited claims, and combinations with various claims are also included within the scope of the technical concept of the present invention.

[0058] The present invention will be described in detail below through examples. However, it should be noted that the examples described below are intended merely to illustrate and embody the present invention and are not intended to limit the scope of the present invention. This is because the scope of the present invention is determined by the matters described in the patent claims and matters reasonably inferred therefrom.

[0059] FIG. 1 is a perspective view illustrating a fastening device for alignment and pressing of a motor core laminate according to an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along line AB of FIG. 1, FIG. 3 is a translucent perspective view illustrating a collet pressing member of FIG. 2, FIG. 4 is a perspective view illustrating a collet of FIG. 2, FIG. 5 is a perspective view illustrating a hollow shaft of FIG. 2, and FIG. 6 is a perspective view illustrating a motor core laminate member to which an embodiment of the present invention is applied.

[0060] Referring to FIGS. 1 to 6, a fastening device for alignment and pressing of a motor core laminate member according to one embodiment of the present invention includes a tubular shaft (300), a collet (100), and a collet pressing member (210).

[0061] Meanwhile, in FIG. 1, reference numeral 500 represents a pressure member that is screw-coupled to the upper end of the hollow shaft (300) and presses the upper cover plate (420) to adjust the upper and lower height of the upper cover plate (420), and reference numeral 470 represents a ring member that supports the lower surface of the pressure member (500) and the upper surface of the upper cover plate (420).

[0062] Referring to FIG. 5, the hollow shaft (300) is provided with a shaft body (310) having a hollow portion (311). A first screw thread (320) is formed on the outer surface of the upper portion of the shaft body (310), and a second screw thread (330) is formed on the outer surface of the lower portion of the shaft body (310). Additionally, a plurality of ventilation holes (340) may be formed in a part of the shaft body (310). These ventilation holes (340) may be formed on the upper portion of the shaft body (310).

[0063] Looking at FIG. 4, the collet (100) is coupled to the circumference of the shaft body (310) and has a hollow portion, and the hollow shaft (300) is coupled to the inner hollow portion of the collet (100).

[0064] This collet (100) includes a circular base portion (130) at the bottom and a wall portion extending upward from the base portion (130). Additionally, a third screw thread (130) is formed on the outer surface of the base portion (130) to be firmly screwed into the second screw thread (330) of the shaft body (310) so as not to loosen.

[0065] The wall portion is formed to have a plurality of slots (114) with the top open, and is formed to be divided into a plurality of support portions (110) with the slots (114) in between by these slots (114). Additionally, the top of the support portion (110) may be formed into a first inclined portion (112) that is bent inward at a predetermined angle of inclination and extends. Additionally, the bottom of the support portion (110) may be formed into a second inclined portion (113) that is bent inward at a predetermined angle of inclination and extends.

[0066] And, the outer diameter of the portion of the wall of the collet (100) that contacts the lower inner surface of the motor core laminate member (hereinafter also referred to as 'laminated body', 10) installed around it is formed to match the inner diameter of the motor core laminate (10), and the outer diameter of the portion corresponding to the upper inner surface of the motor core laminate (10) is formed to be larger than the inner diameter of the motor core laminate (10). To this end, each support portion (110) of the wall may be formed to be inclined outward at a predetermined angle (α).

[0067] Referring to FIG. 6, the motor core laminate (10) is a stamped electrical steel sheet laminate having a hollow portion, and a collet (100) is attached to this hollow portion. When the motor core laminate (10) is attached to the collet (100), each support portion (110) of the upper part, more specifically the wall portion, of the contracted collet (100) elastically supports the inner surface of the motor core laminate (10).

[0068] Additionally, the motor core laminate (10) has an inner surface formed of an uneven tooth portion, and the inner end of this tooth portion is supported by the inclined wall portion of the collet (100) so as to be aligned in the axial direction.

[0069] Looking at FIG. 3, the collet pressing member (210) is coupled to the upper end of the hollow shaft (300) on the upper side of the collet (100) and has a hollow portion (211), and a fourth screw thread (212) is formed on the inner surface of the hollow portion (211) so as to be screw-coupled to the first screw thread (320) of the hollow shaft (300).

[0070] The collet pressing member (210) has a pressing portion (213) formed on its inner surface that protrudes downward at an angle to press the inclined portion (112) of the wall portion of the collet (100) downward.

[0071] The wall portion of the collet (100) is composed of a plurality of support portions (110) that are partially divided by a plurality of axial slots (114). Since the outer diameter in the free state is larger than the inner diameter of the motor core laminate (10), when mounting or removing the motor core laminate (10) from the fastening device, the outer diameter of the collet (10) can be adjusted to be smaller than the inner diameter of the motor core laminate (10) by lowering the collet pressing member (210), which is coupled to the hollow shaft (300) and moves up and down, relative to the outer inclined portion (112) of the support portion (110) of the collet (100).

[0072] Additionally, when the collet pressing member (210) is raised back to its original position while the motor core laminate (10) is mounted around the collet (100), the wall portion attempts to expand back to its original shape due to the elastic force of the wall portion of the collet (100), thereby stably supporting the inner surface of the motor core laminate (10).

[0073] According to this structure, not only can the contact between the collet and the motor core laminate be stably maintained regardless of the difference in relative thermal expansion and contraction between each component and the motor core laminate during heating or cooling, or the variation in the inner diameter dimensions of the motor core laminate member, but the vertical distribution of the lateral contact pressure (lateral pressure) gradually decreases from bottom to top, thereby mitigating the offset of the axial pressure applied downward by the upper pressure plate, so that the pressure can be effectively transmitted to the bottom of the motor core laminate member.

[0074] In addition, since the separate tapered shaft (or arbor) press-fit required in conventional collet mechanisms is unnecessary when expanding the collet, there is an advantage of simplifying the structure of the fastening device, reducing the number of parts to make it lighter, and allowing air to pass through the center of the device.

[0075] And, according to an embodiment of the present invention, an upper pressure plate (420) and a lower pressure plate (430) are respectively disposed at the upper and lower ends of the motor core laminate (10).

[0076] And, it includes a lower base plate (450) positioned on the lower side of the lower pressure plate (430), and a plurality of pins (435) positioned between the lower pressure plate (430) and the lower base plate (450) to support the lower pressure plate (430).

[0077] At this time, the upper and lower ends of the pin (435) are respectively coupled to the first insertion groove formed on the lower surface of the lower pressure plate (430) and the first insertion groove formed on the upper surface of the lower base plate (450), and can be inserted and coupled with the first and second insertion grooves with a gap between them.

[0078] By connecting the lower pressure plate (430) and the lower base plate (450) with a loose-fit type pin (435) in this way, the deformation of the lower base plate (450) caused by the reaction force generated when the fastening device of one embodiment presses the motor core laminate (10) or the difference in temperature distribution during heating or cooling is prevented from being transmitted to the lower pressure plate (430), thereby effectively maintaining the flatness of the lower pressure plate (430).

[0079] In addition, convective heat transfer is possible to the surface exposed by the space provided between the lower pressure plate (430) and the lower base plate (450) by the pin (435), thereby improving heating or cooling efficiency and reducing temperature variation.

[0080] Furthermore, even if the lower base plate (450) in contact with the furnace structure becomes significantly different in temperature from other parts within the fastening device, it is connected by a pin (435) with a small contact area, so the effect of the local temperature difference on the bottom surface is difficult to transmit to the lower pressure plate (430).

[0081] And, according to one embodiment of the present invention, an upper cover plate (420) is arranged to be elastically supported on the upper side of the upper pressure plate (410).

[0082] At this time, a spring (417) is included that is pressurized and supported between the upper pressure plate (410) and the upper cover plate (420). Reference numeral 415 indicates a screw shaft connecting the upper pressure plate (410) and the upper cover plate (420) with the spring (417) attached, and reference numeral 416 indicates a nut that presses the upper cover plate (420). Also, reference numerals 421 and 411 indicate grooves that support the upper and lower ends of the spring (417).

[0083] At this time, by setting the optimal position of the spring (417) to improve the distribution of axial pressure and supporting the inner surface of the motor core laminate (10) through a new structure collet to align it axially, while allowing internal convection through the hollow shaft (300) structure, the temperature distribution during motor core stamping bonding can be further improved.

[0084] Additionally, depending on the configuration of the spring (417), the upper pressure plate (410), and the upper cover plate (420), the radial position can be optimized, and the pressure distribution can be uniformized by preventing the bending of the lower base plate (450) due to the fastening reaction force from deforming the lower pressure plate through a loose fitting pin that supports the lower part.

[0085] In the present invention, the radial position of the pressure spring is optimized to prevent bending of the component due to the fastening reaction force from deforming the pressure plate, thereby uniformizing the pressure distribution in the stacking direction. The structure is modified so that tapered shaft press-fitting is unnecessary when expanding the collet, thereby making the fastening device lighter and simultaneously creating a hollow type that allows air to pass through the center of the device. Additionally, an expansion mandrel mechanism is provided in which the expansion force of the collet is generated and maintained on its own without a coaxial spring during the time the adhesive cures after fastening.

[0086] At this time, the contact pressure (lateral pressure) between the outer surface of the collet and the inner surface of the motor core laminate member is highest at the bottom and gradually decreases as it goes toward the top. Since the frictional resistance formed by the lateral pressure and friction in the vertical direction on the corresponding surface also has the same distribution, there is an effect of reducing the cumulative offset of the compression force due to frictional resistance when the pressure applied by the upper pressure plate compresses each stamping plate within the motor core laminate member during the stage where the upper pressure plate presses the motor core laminate member in the axial direction.

[0087] In addition, in this mandrel structure, there is no need to use the conventional method of pressing a tapered shaft (or arbor) into the inner surface of the collet to expand the collet, so excessive force can be prevented from being applied to the collet, and conversely, shrink fit problems for the motor core laminate member, which has a relatively low temperature during cooling, can also be prevented.

[0088] In addition, the space where the tapered shaft was located can also be left empty. That is, since the central axis of the fastening device can be replaced with a hollow shaft, not only can the mass of the fastening device be reduced, but the existing tapered shaft can also eliminate the element that hinders heating and cooling on the inner side (Teeth side) of the motor core laminate member, and by allowing convection inward, the temperature distribution within the motor core can be improved.

[0089] Figures 6 and 9 are intended to provide a method for improving the distribution of axial pressure by setting the optimal position of the spring.

[0090] To this end, dimensional elements of the motor core laminate member are defined in FIG. 6, and from this, the area S of the pressurized surface of the motor core laminate member core is the area S of the laminate ring relative to the outer diameter of the laminate. total Area S of the slot slotIt can be easily obtained by subtracting.

[0091] Here Igo It is as follows. If the area of ​​the ring is plotted along the radial coordinate r, it can be represented as a graph expressed in terms of the circumference length l, as shown in Figure 6. l min is the length of the circumference of the inner face of the laminate, and l max l is the length of the circumference of the outer surface of the laminate. slot is the length of the circumference at the boundary between the yoke and the tooth. w is r yoke -r teeth is, r yoke is the radius of the laminate, and r teeth is the radius from the center of the laminate to the tip of the tooth.

[0092] And, the total area under the graph is S core It is identical to, and the tooth area S teeth The section corresponding to and the yoke area S yoke It consists of intervals corresponding to . A conditional equation expressed as a quadratic expression based on the assumption that if a pressure point (e.g., a spring) is placed at position x where the left and right areas are equal, the pressure distribution formed on the pressure surface of the laminate can be made uniform. This is derived.

[0093] Here, x= This becomes, and the optimal load point is r optLoad is r teeth It becomes + b + x. Here, k yoke is the slope of the Yoke interval graph (l max -l slot It can be calculated as ) / (wb). By selecting the physically valid solution from the two calculated solutions, the optimal spring installation location can be effectively determined.

[0094] When the upper and lower pressure plates of the fastening device press the laminate, the reaction force (i.e., tensile load) generated in the hollow shaft or thermal deformation during the heating / cooling process causes deformation of the base plate, so that the deformation is not directly propagated to the lower pressure plate, the two plates are supported in the vertical direction by a pin with a clearance fit on one side.

[0095] FIG. 8 is a plan view of a top plate for finding the optimized load point of a spring, and FIG. 9 is a plan view for explaining the relationship between a spring and a pin.

[0096] Referring to FIGS. 8 and 9, by optimizing the radial position of the axial spring (or pin) for compressing the motor core laminate member using the aforementioned relationship, the uniformity of the axial pressure distribution is improved.

[0097] In particular, this method can significantly improve the deviation of the radial pressure. As an example, as shown in FIGS. 7 and 8, the position of the spring is r, which is the halfway point between the inner and outer diameters of the motor core laminate. initial When set to (comparative example) and r, which is the optimal point calculated by the method presented in the present invention optLoad You can compare the case set in (example).

[0098] At this time, the pin supporting the lower pressure plate was positioned to be staggered with respect to the spring located on the upper side in the plan view, as shown in Fig. 9. Total 2 ton f A simulation was conducted to apply pressure to the upper pressure plate by distributing the pressure to eight springs, and the results are explained in detail below.

[0099] FIGS. 10 and FIGS. 11 respectively show the contact pressure distribution formed on the upper surface of a motor core laminate member in a comparative example and a method in which the load point position is optimized according to the present invention. For convenience in visualizing the analysis results, the pressure contour range was adjusted to 0 to 5 MPa.

[0100] Below, comparison example (r initial ) is the contact pressure distribution before optimizing the pressure application load point, and Example (r optLoad ) is the contact pressure distribution after optimizing the pressure application load point.

[0101] Fig. 10 is r initial It indicates the positional load point, and Fig. 11 is r optLoad It indicates the positional load point. Referring to FIGS. 10 and FIGS. 11, regarding the upper surface contact pressure, the comparative example (r initial ) shows a result where the pressure becomes concentrated toward the end of the yoke, reaching a maximum of 39.4 MPa, and drops to 0 MPa at the yoke, but Example (r optLoad In ), the radial pressure distribution is relatively uniform in the radial direction, with only a difference between the spring location (Direct Loading Area) and the spring location (In-Direct Loading Area) along the circumferential direction at a level of about 2 MPa.

[0102] Fig. 12 is r initial It indicates the positional load point, and Fig. 13 is r optLoad It indicates the positional load point. Looking at Figures 12 and 13, the contact pressure on the lower surface also shows a relatively superior pressure distribution in the example compared to the comparative example.

[0103] In addition, the same contact pressure improvement results are graphed in FIGS. 16 to 18 along the coordinate axes defined in FIGS. 14 and 15. FIG. 14 is based on an arc passing through the tooth portion, and FIG. 15 is based on an arc passing through the yoke portion.

[0104] Figure 16 defines the coordinate axes in the radial direction and represents the contact pressure of the comparative example and the embodiment, comparing the radial pressure distribution on the upper and lower surfaces for the spring pressure point passing through the load point (Direct Loading Area) and the non-passage area between the load point (In-Direct Loading Area).

[0105] Looking at Fig. 16, in the comparative example, the contact pressure was generally low and the difference in contact pressure between the spring pressure point area and the non-spring pressure area was not large, whereas in the embodiment, the contact pressure was higher than in the comparative example and the difference in contact pressure between the spring pressure point area and the non-spring pressure area was large compared to the comparative example.

[0106] FIG. 17 shows the contact pressure of a comparative example and an embodiment, comparing the circumferential pressure distribution of the tooth portion and the yoke portion in terms of the pressure applied to the upper surface of the motor core. Referring to FIG. 17, it can be seen that in the case of the comparative example, there is a large difference in the contact pressure between the tooth portion and the yoke portion, whereas in the case of the embodiment, the contact pressure between the tooth portion and the yoke portion is within a similar range.

[0107] FIG. 18 shows the contact pressure of a comparative example and an embodiment, and compares the circumferential pressure distribution of the tooth portion and the yoke portion regarding the pressure applied to the lower surface of the motor core. Looking at FIG. 18, it can be seen that in the case of the embodiment, the contact pressure of the tooth portion and the yoke portion is within a similar range.

[0108] FIG. 19 compares the axial stress distribution within the motor core of a comparative example and an embodiment, showing that when the pressure distribution between the tooth portion and the yoke portion is skewed to one side, localized tensile stress may occur even when a bending moment is generated in the motor core laminate and pressure is applied. At this time, for convenience in visualizing the tensile stress region, the minimum value of the axial stress contour range is adjusted to 0 MPa. The dark gray area is a compressive stress region where the axial stress is 0 MPa or less, and the colored area is a tensile stress region where the axial stress is 0 MPa or more.

[0109] As shown in FIGS. 14 to 19, in the case of the comparative example, tensile stress occurs in the outer lower region of the motor core, whereas in the embodiment, it is predicted that there is almost no tensile stress region.

[0110] (Explanation of symbols)

[0111] 10: Motor core laminate member (laminated body)

[0112] 100: Collet

[0113] 110: Support

[0114] 210: Collet pressurizing member

[0115] 300: Hollow shaft

[0116] 410: Upper pressure plate

[0117] 417: Spring

[0118] 420: Upper cover plate

[0119] 430: Lower pressure plate

[0120] 470: Ring member

[0121] 500: Pressure member

Claims

1. A collet in which the outer diameter of the lower portion matches the inner diameter of a motor core laminate member coupled to the circumference, and the outer diameter of the upper portion is formed to be larger than the inner diameter of the motor core laminate member; and A hollow shaft coupled to the hollow portion of the above collet; comprising, A fastening device for aligning and pressing a motor core laminate member, wherein when the motor core laminate member is coupled to the collet, the upper portion of the contracted collet is elastically supported on the inner circumference of the motor core laminate.

2. In Paragraph 1, The above collet is a fastening device for aligning and pressing motor core laminate members, wherein the wall portion is formed to have a plurality of slots with the top open.

3. In Paragraph 2, A fastening device for aligning and pressing a motor core laminate member, comprising: a lower base portion; a plurality of support portions extending vertically from the base portion with the slot in between; and an inclined portion extending inwardly at an angle from the upper end of the support portion.

4. In Paragraph 3, A fastening device for aligning and pressing a motor core laminate member, comprising: a collet pressing member coupled to the upper part of the hollow shaft, wherein the inner surface is formed as a protrusion protruding downward to press the inclined portion downward.

5. In Paragraph 1, A fastening device for aligning and pressing a motor core laminate member, comprising an upper pressure plate and a lower pressure plate positioned to be in close contact with the upper and lower ends, respectively, of the motor core laminate member coupled to the above collet.

6. In Paragraph 5, A fastening device for aligning and pressing a motor core laminate member, comprising: a lower base plate disposed on the lower side of the lower pressure plate; and a plurality of pins disposed to support between the lower pressure plate and the lower base plate.

7. In Paragraph 6, A fastening device for aligning and pressing a motor core laminate member, wherein the pin is inserted with a gap between a first insertion groove formed on the lower surface of the lower pressure plate and a second insertion groove formed on the upper surface of the lower base plate.

8. In Paragraph 5, A fastening device for aligning and pressing a motor core laminate member, comprising an upper cover plate positioned to be elastically supported on the upper side of the upper pressure plate.

9. In Paragraph 8, A fastening device for aligning and pressing a motor core laminate member, comprising a spring disposed between the upper pressure plate and the upper cover plate to support the upper cover plate.

10. In Paragraph 9, The position of the above spring (r optLoad A fastening device for alignment and pressure of a motor core laminate member, wherein ) is set by the following equation. , , x= , provided that among the two years r optLoad A solution x is selected that does not exceed the dimensions of the above motor core laminate member, and r optLoad = r teeth + b + x Here, S core is the area of ​​the pressurized surface of the motor core laminate member, and S total is the area of ​​the stacked ring, and S slot is the area of ​​the slot, and S teeth is the area of ​​the tooth portion, and S yoke is the area of ​​the yoke, and l min is the length of the circumference of the inner face of the laminate, and l max is the length of the circumference of the outer surface of the laminate, and l slot is the length of the circumference at the boundary between the yoke and the tooth, and w is r yoke -r teeth is, r yoke is the radius of the laminate, and r teeth is the radius from the center of the laminate to the tip of the tooth, b is the length of the slot along the radial direction, and x is r in the radial direction from the center of the laminate. teeth As the slope of increase in the circumferential length of the yoke portion with respect to the radius position from the point at + b to the outer surface of the laminate (l max - l slot ) / (wb)is.

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