Motor

Abstract

A rotor according to one embodiment of the present disclosure may comprise a shaft, a plurality of magnets, a casing and a rotor core. The rotor core can include a plurality of first core layers and a plurality of second core layers. Each of the plurality of first core layers can include: a base part through which the shaft passes; a plurality of core parts spaced apart from each other in the circumferential direction of the base part; and a plurality of bridge parts, each extending toward the base part from a corresponding core part from among the plurality of core parts and bent toward the corresponding core part.

Description

motor

[0001] Various embodiments of the present disclosure relate to a rotor including a fully split type rotor core.

[0002] A motor is a mechanical device that obtains rotational power from electrical energy. It consists of a stator and a rotor. The motor rotates as the rotor and stator interact electromagnetically.

[0003] Among the various types of motors, permanent magnet motors that use permanent magnets to form a magnetic field can be divided into surface permanent magnet (SPM) permanent magnet motors and interior permanent magnet (IPM) permanent magnet motors.

[0004] As a type of embedded permanent magnet motor, the spoked permanent magnet motor boasts a structurally high magnetic flux concentration, enabling high torque and high output. Furthermore, it allows for miniaturization of the motor for a given output. Therefore, it can be used in drive motors requiring high torque and output, such as washing machines and electric vehicles.

[0005] A rotor of a spoke-type permanent magnet motor includes a shaft, a rotor core through which the shaft passes, and a plurality of magnets (e.g., permanent magnets) inserted into the rotor core.

[0006] Rotor cores are typically manufactured by pressing thin steel sheets supplied in strips into individual sheets, which are then laminated. A rotor core comprises a base portion through which a shaft passes, core portions arranged along the circumference of the base portion, and a bridge portion connecting the base portion and the core portions.

[0007] In the case of a spoke-type permanent magnet motor like this, when the motor is operating, some of the magnetic flux may leak to the shaft side through the bridge portion of the rotor core, and the efficiency of the motor may decrease due to the influence of this leakage magnetic flux.

[0008] Various embodiments of the present disclosure can provide a rotor core including a plurality of core portions divided by a punching action of a mold device during insert injection molding.

[0009] A rotor according to one embodiment of the present disclosure may include a shaft, a plurality of magnets, a casing, and a rotor core. The rotor core may include a plurality of first core layers and a plurality of second core layers. Each of the plurality of first core layers may include a base portion through which the shaft passes, a plurality of core portions spaced apart from each other along a circumferential direction of the plurality of base portions, and a plurality of bridge portions each extending from a corresponding core portion among the plurality of core portions toward the base portion and bent toward the corresponding core portion.

[0010] A rotor according to one embodiment of the present disclosure may include a shaft, a plurality of magnets, a casing, and a rotor core. The rotor core may include a through hole into which the shaft is inserted, a plurality of first core layers, and a plurality of second core layers. Each of the plurality of first core layers may include a plurality of core portions spaced apart from each other along a circumferential direction of the through hole, and a plurality of bridge portions including a pair of catch protrusions that protrude in both directions in the circumferential direction toward an outer end of each core portion among the plurality of core portions and are bent toward the core portions.

[0011] A method for manufacturing a rotor including a shaft, a plurality of magnets, a casing, and a rotor core according to one embodiment of the present disclosure may include a step of forming a rotor core by laminating a first core layer including a plurality of bridge portions and a second core layer not including the plurality of bridge portions. The method for manufacturing the rotor may include a step of seating the rotor core in a lower mold. The method for manufacturing the rotor may include a step of mounting a plurality of magnets on the rotor core. The method for manufacturing the rotor may include a step of lowering an upper mold provided with a punching portion to punch out the bridge portions of the first core layer.

[0012] According to various embodiments of the present disclosure, during insert injection molding, the base portion and bridge portion of the rotor core can be separated by a punching action of the mold device, thereby dividing the core portions connected to the base portion. In this case, magnetic flux leakage toward the shaft through the bridge portion can be prevented during motor operation, thereby increasing motor efficiency.

[0013] In addition, since the bridge portion bent toward the rotor core according to the punching action of the mold device during insert injection molding is surrounded by the resin constituting the injection member, the separation of the divided core portions during motor operation can be prevented.

[0014] The effects that can be achieved by the exemplary embodiments of the present disclosure can be clearly derived and understood by those skilled in the art to which the exemplary embodiments of the present disclosure pertain, from the following description. In other words, unintended effects resulting from the implementation of the exemplary embodiments of the present disclosure can also be derived by those skilled in the art from the exemplary embodiments of the present disclosure.

[0015] In connection with the description of the drawings, the same or similar reference numerals may be used for identical or similar components.

[0016] Figure 1 is a perspective view of a rotor according to one embodiment.

[0017] Figure 2 is a cross-sectional view taken along line Ⅰ-Ⅰ' shown in Figure 1.

[0018] Figure 3 is a cross-sectional view taken along line Ⅱ-Ⅱ' shown in Figure 1.

[0019] Figure 4 is a cross-sectional view of a rotor according to one embodiment.

[0020] FIG. 5 is a perspective view of a rotor core before punching, according to one embodiment.

[0021] Figure 6 is a cross-sectional view taken along line Ⅲ-Ⅲ' shown in Figure 5.

[0022] Figure 7 is a plan view of a rotor core before punching, according to one embodiment.

[0023] FIG. 8 is a cross-sectional view of a rotor core in a post-punching state according to one embodiment.

[0024] FIG. 9 is a plan view of a rotor core in a post-punching state according to one embodiment.

[0025] Figure 10 is a graph for comparing the efficiency of the motor before and after punching the bridge section.

[0026] Figure 11 is a manufacturing flowchart of a rotor according to one embodiment.

[0027] Figures 12a, 12b and 12c are drawings showing a manufacturing process of a rotor according to one embodiment.

[0028] Figure 13 is a side view of a rotor according to one embodiment.

[0029] Fig. 14 is a cross-sectional view taken along line Ⅳ-Ⅳ' shown in Fig. 13.

[0030] Figure 15 is a perspective view of a rotor core before punching, according to one embodiment.

[0031] Figure 16 is a side view of a rotor core before punching, according to one embodiment.

[0032] Figure 17 is a plan view of a rotor core before punching, according to one embodiment.

[0033] FIG. 18 is a side view of a rotor core after punching, according to one embodiment.

[0034] FIG. 19 is a plan view of a rotor core after punching, according to one embodiment.

[0035] It should be understood that the various embodiments and terms used in this document are not intended to limit the technical features described in this document to specific embodiments, but rather to include various modifications, equivalents, or substitutes of the embodiments.

[0036] In connection with the description of the drawings, similar reference numerals may be used for similar or related components.

[0037] The singular form of a noun corresponding to an item may include one or more items, unless the context clearly indicates otherwise.

[0038] In this document, each of the phrases "A or B", "at least one of A and B", "at least one of A or B", "A, B, or C", "at least one of A, B, and C", and "at least one of A, B, or C" may include any one of the items listed together in that phrase, or all possible combinations thereof.

[0039] Terms such as "first," "second," or "first" or "second" may be used simply to distinguish one component from another and do not qualify the components in any other respect (e.g., importance or order).

[0040] When a component (e.g., a first component) is referred to as being “coupled” or “connected” to another component (e.g., a second component), with or without the terms “functionally” or “communicatively,” it means that the component can be connected to the other component directly (e.g., wired), wirelessly, or through a third component.

[0041] The terms “include” or “have” are intended to specify the presence of a feature, number, step, operation, component, part or combination thereof described in this document, but do not preclude the presence or addition of one or more other features, numbers, steps, operations, components, parts or combinations thereof.

[0042] When a component is said to be “connected,” “coupled,” “supported,” or “in contact with” another component, this includes not only cases where the components are directly connected, coupled, supported, or in contact, but also cases where the components are indirectly connected, coupled, supported, or in contact through a third component.

[0043] When we say that a component is "on" another component, this includes not only cases where the component is in contact with the other component, but also cases where there is another component between the two components.

[0044] The term “and / or” includes any combination of a plurality of related described elements or any one of a plurality of related described elements.

[0045] The operating principle and embodiments of the present invention will be described with reference to the attached drawings below.

[0046] A motor is a mechanical device that converts electrical energy into mechanical energy (e.g., kinetic energy). A motor may include a rotor (e.g., a rotor (1) of FIG. 1) and a stator (not shown) that interact electromagnetically. The motor can rotate the rotor (1) through the electromagnetic interaction between the rotor (1) and the stator. Specifically, when current is applied to the stator, the rotor (1) rotates due to the electromagnetic interaction with the stator, and power, such as rotational force, can be provided to a power device including the motor through a shaft coupled to the rotor (1).

[0047] Figure 1 is a perspective view of a rotor according to one embodiment.

[0048] Figure 2 is a cross-sectional view taken along line Ⅰ-Ⅰ' shown in Figure 1.

[0049] Figure 3 is a cross-sectional view taken along line Ⅱ-Ⅱ' shown in Figure 1.

[0050] Figure 4 is a cross-sectional view of a rotor according to one embodiment.

[0051] Referring to FIGS. 1 to 3, a rotor (1) according to one embodiment may include a shaft (10), a plurality of magnets (20), and a rotor core (100).

[0052] According to one embodiment, the shaft (10) can be coupled with the rotor core (100). In one embodiment, the shaft (10) can be coupled to the inside of the rotor core (100) by passing through the through hole (101) of the rotor core (100). The shaft (10) can be coupled to the rotor core (100) by, for example, an insert injection method.

[0053] According to one embodiment, a plurality of magnets (20) may be inserted and mounted inside the rotor core (100). In one embodiment, the plurality of magnets (20) may be positioned radially outside the through hole (101) of the rotor core (100). In one embodiment, the plurality of magnets (20) may be arranged at a predetermined interval along the circumferential direction of the through hole (101). Each of the plurality of magnets (20) may be inserted into a slot (103) formed between the split rotor cores (102) of the rotor core (100) and fixed inside the rotor core (100).

[0054] According to one embodiment, the rotor core (100) may include a through hole (101), a plurality of segmented rotor cores (102) and a plurality of slots (103).

[0055] In one embodiment, a through hole (101) may be formed in the center of the rotor core (100). In one embodiment, the through hole (101) may extend in a vertical direction. The shaft (10) may be inserted into the through hole (101) and coupled with the rotor core (100).

[0056] In one embodiment, a plurality of split rotor cores (102) may be positioned radially outside the through hole (101) of the rotor core (100). The plurality of split rotor cores (102) may be arranged at a predetermined interval along the circumferential direction of the through hole (101). A slot (103), which is a space into which a plurality of magnets (20) are inserted, may be formed between the plurality of split rotor cores (102). In one embodiment, the plurality of split rotor cores (102) may be formed by splitting the core portions (112, 121) of the laminated core layers (110, 120) by a punching operation of the mold device (200) during insert injection molding.

[0057] According to one embodiment, the rotor core (100) may be manufactured by laminating a plurality of thin steel plates. In one embodiment, the rotor core (100) may include a plurality of first core layers (110) and a plurality of second core layers (120) in which a plurality of thin steel plates are laminated. In one embodiment, the steel plates constituting the plurality of first core layers (110) and the steel plates constituting the plurality of second core layers (120) may have different shapes. In one embodiment, the rotor core (100) may be formed by alternately laminating a plurality of first core layers (110) and a plurality of second core layers (120). The first core layers (110) may be disposed, for example, at the top and bottom of the rotor core (100), but the present disclosure is not limited thereto.

[0058] According to one embodiment, the first core layer (110) may include a base portion (111), a plurality of first core portions (112), and a plurality of bridge portions (113).

[0059] In one embodiment, the base portion (111) may have a ring shape. In one embodiment, the base portion (111) may include a hole (111a) through which the shaft (10) passes.

[0060] According to one embodiment, the plurality of first core parts (112) may be spaced apart from the base part (111) by a predetermined distance. In one embodiment, the plurality of first core parts (112) may be arranged spaced apart from the base part (111) by a predetermined distance along the circumferential direction of the base part (111) with the base part (111) as the center.

[0061] According to one embodiment, each of the plurality of first core portions (112) may include a pair of catch protrusions (1121) protruding from the outer end (112a) in both directions in the circumferential direction. In one embodiment, the pair of catch protrusions (1121) may be filled in the outer surface and / or slot (103) of the magnet (20) mounted on the rotor core (100) and may come into contact with the resin surrounding the magnet (20) to prevent the magnet (20) from being separated from the rotor core (100).

[0062] According to one embodiment, each of the plurality of first core portions (112) may include a pair of bending grooves (1122) provided at the inner end (112b) and formed on both sides of the bridge portion (113). In one embodiment, the pair of bending grooves (1122) may be formed by cutting or recessing a predetermined section from the inner end (112b) of the first core portion (112) to the outer end (112a) on both sides of the bridge portion (113). During insert injection molding, resin may be filled into the rotor core (100) through the pair of bending grooves (1122) to surround the bridge portion (113).

[0063] According to one embodiment, a plurality of bridge portions (113) may be provided on the inner end (112b) of each of a plurality of first core portions (112). In one embodiment, the bridge portions (113) may be bent so that at least a portion thereof faces the inner surface of the first core portion (112). In one embodiment, the bridge portions (113) may be spaced apart from the base portion (111) by a predetermined distance (g).

[0064] According to one embodiment, the bridge portion (113) may include a connecting portion (1131) extending inwardly from the inner end (112b) of the first core portion (112) and a hooking portion (1132) bent at a predetermined angle from the connecting portion (1131).

[0065] In one embodiment, the catch (1132) may be bent so as to be perpendicular to the connecting portion (1131). For example, the catch (1132) may extend vertically downward from the extension portion (1131).

[0066] Referring to FIG. 4, the bridge portion (113') of the first core layer (110') according to one embodiment extends inward from the inner end (112b) of the first core portion (112) and may include a catch portion (1133) bent at a predetermined angle from the first core portion (112). Unlike the bridge portion (113) illustrated in FIG. 3, the bridge portion (113') illustrated in FIG. 4 may be composed of a single catch portion (1133).

[0067] In one embodiment, the catch (1133) may be formed by bending so as to be inclined relative to the first core portion (112). For example, the catch (1133) may extend downwardly from the first core portion (112) at an inclined angle.

[0068] In one embodiment, the catch portions (1132, 1133) may be formed by the connection between the bridge portion (113a in FIG. 12b) and the base portion (111) being broken by the downward movement of the punching portion (222) (e.g., the punching portion (222) in FIG. 12b) provided in the upper mold (e.g., the upper mold (220) in FIG. 12b) during insert injection molding, and the bridge portion (113a) being bent to face the inner surface of the first core portion (112). Hereinafter, a method for forming the catch portions (1132, 1133) will be described with reference to FIGS. 11 to 12c.

[0069] According to one embodiment, the second core layer (120) may include a plurality of second core portions (121). In one embodiment, the plurality of second core portions (121) may be arranged at a predetermined interval along the circumferential direction of the through hole (101) centered on the through hole (101) of the rotor core (100). In one embodiment, the plurality of second core portions (121) may have substantially the same arrangement or stacked structure as the plurality of first core portions (112). For example, the plurality of first core portions (112) and the plurality of second core portions (121) may be alternately stacked to form a split rotor core (102). In one embodiment, unlike the first core layer (110), the second core layer (120) may not include a base portion (111) and a bridge portion (113).

[0070] According to one embodiment, the rotor (1) may include an injection member (30) surrounding at least a portion of the rotor core (100). The injection member (30) may also be referred to as a casing.

[0071] In one embodiment, the injection member (30) can be formed by injecting and curing resin into a cavity between internal gaps of the rotor core (100) while a plurality of magnets (20) are mounted on the rotor core (100).

[0072] In one embodiment, a portion of the resin injected into the rotor core (100) may be injected into the rotor core (100) through the gap (g) between the base portion (111) and the bridge portion (113), and a portion of the resin may entirely surround the engaging portion (1132) of the bridge portion (113). In this case, since the plurality of split rotor cores (102) are engaged with the injection member (30) by the engaging portion (1132) of the bridge portion (113), the plurality of split rotor cores (102) may be prevented from flying outward due to the rotational force of the motor when the motor is operated.

[0073] FIG. 5 is a perspective view of a rotor core before punching, according to one embodiment.

[0074] Figure 6 is a cross-sectional view taken along line Ⅲ-Ⅲ' shown in Figure 5.

[0075] Figure 7 is a plan view of a rotor core before punching, according to one embodiment.

[0076] FIG. 8 is a cross-sectional view of a rotor core in a post-punching state according to one embodiment.

[0077] FIG. 9 is a plan view of a rotor core in a post-punching state according to one embodiment.

[0078] Figure 10 is a graph for comparing the efficiency of the motor before and after punching the bridge section.

[0079] Figures 5 to 7 are drawings showing a rotor core (100a) including a first core layer (110a) in which a plurality of first core portions (112) are connected to a base portion (111) via bridge portions (113a). That is, Figures 5 to 7 show a rotor core (100a) including bridge portions (113a) before being punched by a mold device (e.g., mold device (200) of Figures 12A, 12B, and 12C).

[0080] Figures 8 and 9 are drawings showing a rotor core (100) including a first core layer (110) with a base portion (111) and a plurality of first core portions (112) spaced apart from each other. That is, Figures 8 and 9 show a rotor core (100) including a bridge portion (113) after being punched by a mold device (200).

[0081] Referring to FIGS. 5 to 7, a first core layer (110a) of a rotor core (100a) according to one embodiment may include a plurality of bridge portions (113a) connecting a base portion (111) and a plurality of first core portions (112). When a plurality of first core portions (112) are connected to the base portion (111) by a plurality of bridge portions (113a), the base portion (111), the plurality of first core portions (112), and the plurality of bridge portions (113a) may form a magnetic path when the motor is operated. As magnetic flux leaks toward the shaft (10) through the bridge portions (113a), the efficiency of the motor may decrease.

[0082] In order to reduce the leakage flux through the bridge portion (113a), it is necessary to disconnect the plurality of first core portions (112) and the base portion (111) as shown in FIGS. 1 to 4.

[0083] Referring to FIGS. 8 and 9, a first core layer (110) of a rotor core (100) according to one embodiment may include a bridge portion (113) spaced apart from a base portion (111) by a predetermined distance. The bridge portion (113) and the base portion (111) of the first core layer (110) may be disconnected from each other so that a gap (g) may be formed therebetween. Each of a plurality of first core portions (112) may be divided from the base portion (111), and accordingly, the base portion (111), the plurality of first core portions (112), and the bridge portions (113) may not form a magnetic path, so that magnetic flux leakage toward the shaft (10) through the bridge portions (113) may be reduced.

[0084] Referring to FIG. 10, it can be confirmed that the counter electromotive force when the plurality of first core parts (112) and the base part (111) are disconnected as shown in FIGS. 8 and 9 increases by about V (e.g., about 10%) compared to when the plurality of first core parts (112) and the base part (111) are connected through the bridge part (113a) as shown in FIGS. 5 to 7, and in this case, the efficiency of the motor can also increase significantly (e.g., about 3%).

[0085] Hereinafter, with reference to FIGS. 11 to 12C, a method for manufacturing a rotor core (100) including a plurality of divided first core portions (112) by cutting (or punching) a bridge portion (113) of a first core layer (110) from a base portion (111) will be described.

[0086] Figure 11 is a manufacturing flowchart of a rotor according to one embodiment.

[0087] Figures 12a, 12b and 12c are drawings showing a manufacturing process of a rotor according to one embodiment.

[0088] Fig. 12a is a drawing showing a rotor core (100a) coupled with a shaft (10) seated in a lower mold (210). Fig. 12b is a drawing showing a state in which an upper mold (220) is lowered toward the rotor core (100a) seated in the lower mold (210) and a bridge portion (113a) of the rotor core (100a) is punched. Fig. 12c is a drawing showing a state in which a rotor (1) is completed by injecting and hardening resin into a mold device (200) by an insert injection molding method after the punching of the bridge portion (113) of the rotor core (100) is completed.

[0089] Referring to FIGS. 11, 12a, 12b and 12c, a method for manufacturing a rotor (1) according to one embodiment may include a step of forming a rotor core (100a) by alternately stacking a first core layer (110a) and a second core layer (120) having different shapes (1110).

[0090] According to one embodiment, a method for manufacturing a rotor (1) may include a step of joining a rotor core (100a) and a shaft (10) by inserting the shaft (10) into a through hole (101) of a rotor core (100a) (1120). In some embodiments, the shaft (10) may be joined to the rotor core (100) by being inserted into the through hole (101) after the rotor core (100) is insert injection molded in step 1140, which will be described later. In this case, the structure of the mold device may be partially changed so that resin is not filled into the through hole (101) of the rotor core (100) during insert injection molding.

[0091] According to one embodiment, a method for manufacturing a rotor (1) may include a step (1130) of mounting a plurality of magnets (20) inside a rotor core (100a). After the rotor core (100a) is mounted on a lower mold (210), each of the plurality of magnets (20) may be inserted and mounted into a slot (103) provided between the plurality of core portions (112, 121).

[0092] According to one embodiment, a method for manufacturing a rotor (1) may include a step (1140) of punching a bridge portion (113a) of a rotor core (100a).

[0093] According to one embodiment, the upper mold (220) of the mold device (200) may include a pair of punching portions (222) protruding from the lower surface at positions facing the bridge portion (113a) of the rotor core (100a). In one embodiment, the pair of punching portions (222) may include a tip portion (222a) inclined at the free end.

[0094] Referring to FIGS. 12A and 12B, in one embodiment, when the upper mold (220) is lowered toward the rotor core (100a), the punching portion (222) of the upper mold (220) comes into contact with the bridge portion (113a) of the rotor core (100a). Thereafter, when the upper mold (220) continues to be lowered, the bridge portion (113a) is severed from the base portion (111) by the clamping force of the upper mold (220), and the free end of the severed bridge portion (113a) is bent to a predetermined portion toward the inner surface of the rotor core (100). In this way, as the bridge portion (113a) of the rotor core (100a) is severed from the base portion (111) by the lowering motion of the upper mold (220), each of the core portions (112, 121) is completely divided.

[0095] According to one embodiment, a method for manufacturing a rotor (1) may include a step (1150) of injection-molding an injection member (30) by injecting and curing a resin into a rotor core (100). Referring to FIG. 12c, a gap (g) is formed between the disconnected bridge portion (113) and the base portion (111) of the rotor core (100) by the aforementioned step 1140. When the resin is injected into the mold device (200), the resin is filled into the rotor core (100) through the internal gap of the rotor core (100), such as the gap (g), and is cured. A portion of the injected resin may surround the bridge portion (113) and firmly fix the split rotor cores (102) into the rotor (1).

[0096] Figure 13 is a side view of a rotor according to one embodiment.

[0097] Fig. 14 is a cross-sectional view taken along line Ⅳ-Ⅳ' shown in Fig. 13.

[0098] Referring to FIGS. 13 and 14, a rotor (1') according to one embodiment may include a shaft (10), a plurality of magnets (20), an injection member (30'), and a rotor core (300).

[0099] According to one embodiment, the shaft (10) may be coupled to the rotor core (300). In one embodiment, the shaft (10) may be coupled to the inside of the rotor core (300) by passing through the through hole (301) of the rotor core (300).

[0100] According to one embodiment, a plurality of magnets (20) may be inserted and mounted inside the rotor core (300). In one embodiment, the plurality of magnets (20) may be positioned radially outside the through hole (301) of the rotor core (300). In one embodiment, the plurality of magnets (20) may be arranged at a predetermined interval along the circumferential direction of the through hole (301). Each of the plurality of magnets (20) may be inserted into a slot (303) formed between the split rotor cores (302) of the rotor core (300) and fixed inside the rotor core (300).

[0101] According to one embodiment, the rotor core (300) may include a through hole (301), a plurality of segmented rotor cores (302), and a plurality of slots (303).

[0102] In one embodiment, a through hole (301) may be formed in the center of the rotor core (300). In one embodiment, the through hole (301) may extend in the vertical direction. The shaft (10) may be inserted into the rotor core (300) by penetrating the through hole (301), and the shaft (10) and the rotor core (300) may be coupled as resin is injected and hardened into the through hole (301) while the shaft (10) is penetrating the through hole (301).

[0103] In one embodiment, a plurality of split rotor cores (302) may be positioned radially outside the through hole (301) of the rotor core (300). In one embodiment, the plurality of split rotor cores (302) may be arranged at a predetermined interval along the circumferential direction of the through hole (301). A slot (303), which is a space into which a plurality of magnets (20) are inserted, may be formed between the plurality of split rotor cores (302). In one embodiment, the plurality of split rotor cores (302) may be split by a punching operation of the mold device (200) during insert injection molding of the core portions (311) of the laminated core layers (310, 120).

[0104] According to one embodiment, the rotor core (300) may be manufactured by laminating a plurality of thin steel plates. In one embodiment, the rotor core (300) may include a plurality of first core layers (310) and a plurality of second core layers (120) in which a plurality of thin steel plates are laminated. In one embodiment, the steel plates constituting the plurality of first core layers (310) and the steel plates constituting the plurality of second core layers (120) may have different shapes. In one embodiment, the rotor core (300) may be formed by alternately laminating a plurality of first core layers (310) and a plurality of second core layers (120). The first core layers (310) may be disposed, for example, at the top and bottom of the rotor core (300), but the present disclosure is not limited thereto.

[0105] According to one embodiment, the first core layer (310) may include a plurality of first core portions (311) and a plurality of bridge portions (312).

[0106] According to one embodiment, a plurality of first core parts (311) may be arranged at a predetermined interval along the circumferential direction of the through hole (301) with the through hole (301) as the center. In one embodiment, a resin constituting an injection member (30') may be filled and cured between the plurality of first core parts (311) and the shaft (10) inserted into the through hole (301).

[0107] According to one embodiment, each of the plurality of bridge portions (312) may include a pair of catch projections (3121, 3122) protruding from the outer end (311a) of the first core portion (311) in both directions in the circumferential direction.

[0108] In one embodiment, a pair of catches (3121, 3122) may be bent to face opposite sides of the first core portion (311). In one embodiment, a pair of catches (3121, 3122) may extend obliquely from an outer end (311a) of the first core portion (311) toward another first core portion (311) adjacent to the first core portion (311). In one embodiment, the catches (3121, 3122) of adjacent bridge portions (312) may be spaced apart from each other by a predetermined interval.

[0109] According to one embodiment, the second core layer (120) may not include a bridge portion (312) unlike the first core layer (310).

[0110] According to one embodiment, the injection member (30') can be formed by injecting and curing resin into a cavity between internal gaps of the rotor core (300) while a plurality of magnets (20) are mounted on the rotor core (300).

[0111] In one embodiment, a portion of the resin injected into the rotor core (300) may be injected into the rotor core (300) through a gap between adjacent bridge portions (312), and a portion of the resin may entirely surround the engaging projections (3121, 3122) of the bridge portions (312). Since the plurality of split rotor cores (302) are engaged with the injection member (30') by the engaging projections (3121, 3122) of the bridge portions (312), the plurality of split rotor cores (102) may be prevented from flying outward by the rotational force of the motor when the motor is in operation.

[0112] Figure 15 is a perspective view of a rotor core before punching, according to one embodiment.

[0113] Figure 16 is a side view of a rotor core before punching, according to one embodiment.

[0114] Figure 17 is a plan view of a rotor core before punching, according to one embodiment.

[0115] FIG. 18 is a side view of a rotor core after punching, according to one embodiment.

[0116] FIG. 19 is a plan view of a rotor core after punching, according to one embodiment.

[0117] Figures 15 to 17 are drawings showing a rotor core (300a) including a first core layer (310a) in which adjacent first core portions (311) are connected to each other through bridge portions (312a). Figures 15 to 17 show a rotor core (300a) including a bridge portion (312a) before being punched by a mold device (e.g., mold device (200) of Figures 12a, 12b, and 12c).

[0118] Figures 18 and 19 are drawings showing a rotor core (300) including a first core layer (310) with a plurality of first core portions (311) spaced apart from each other. Figures 18 and 19 show a rotor core (300) including a bridge portion (312) after being punched by a mold device (200).

[0119] Referring to FIGS. 15 to 17, a first core layer (310a) of a rotor core (300a) according to one embodiment may include a bridge portion (312a) that connects adjacent first core portions (311) to each other. When a plurality of first core portions (311) are connected to each other by the bridge portion (312a), the efficiency of the motor may decrease due to leakage flux flowing along the bridge portion (312a) during operation of the motor.

[0120] In order to reduce the leakage flux through the bridge portion (312a), it is necessary to separate the adjacent first core portions (311) by disconnecting them from each other, as shown in FIGS. 13 and 14.

[0121] Referring to FIGS. 18 and 19, a first core layer (310) of a rotor core (300) according to one embodiment may include a plurality of first core portions (311) spaced apart from each other. For example, the plurality of first core portions (311) may be divided from each other by punching the bridge portions (312a) connecting the plurality of first core portions (311a) of FIGS. 15 to 17 through a mold device (200). In this case, magnetic flux leakage through the bridge portions (312a) may be reduced.

[0122] A rotor (1) according to one embodiment of the present disclosure may include a shaft (10), a plurality of magnets (20), a casing (30), and a rotor core (100). The rotor core (100) may include a plurality of first core layers (110) and a plurality of second core layers (120). The first core layer (110) may include a base portion (111) through which the shaft (10) passes. The first core layer (110) may include a plurality of core portions (112) spaced apart from each other along a circumferential direction of the base portion (111). The first core layer (110) may include a plurality of bridge portions (113, 113'), each of which extends from a corresponding core portion (112) among the plurality of core portions (112) toward the base portion (111) and is bent toward the corresponding core portion (112).

[0123] According to one embodiment, each of the plurality of bridge portions (113) can be bent vertically from the corresponding core portion (112).

[0124] According to one embodiment, each of the plurality of bridge portions (113') can be bent at an angle from the corresponding core portion (112).

[0125] According to one embodiment, the core portion (112) of the plurality of first core layers (110) may include a plurality of first core portions (112), and the second core layer (120) may include a plurality of second core portions (121) that are not connected to the plurality of bridge portions (113, 113').

[0126] According to one embodiment, the plurality of first core layers (110) and the plurality of second core layers (120) may be alternately stacked in the vertical direction.

[0127] According to one embodiment, each of the plurality of bridge portions (113) may be spaced apart from the base portion (111) by a predetermined distance (g).

[0128] According to one embodiment, each of the plurality of core portions (112) may include a pair of bending grooves (1122) arranged on each side of a bridge portion (113) extending from each of the core portions (112).

[0129] According to one embodiment, the casing (30) may include a resin surrounding the rotor core (100) and at least a portion of each of the plurality of magnets (20).

[0130] A rotor (1) according to one embodiment of the present disclosure may include a shaft (10), a plurality of magnets (20), a casing (30'), and a rotor core (300). The rotor core (300) may include a through hole (301) into which the shaft (10) is inserted, a plurality of first core layers (310), and a plurality of second core layers (320). The first core layer (310) may include a plurality of core portions (311) spaced apart from each other along a circumferential direction of the through hole (301). The first core layer (310) may include a plurality of bridge portions (312) that protrude in both directions in the circumferential direction toward an outer end (311a) of each core portion (311) among the plurality of core portions (311) and include a pair of catch protrusions (3121, 3122) bent toward the core portions (311).

[0131] According to one embodiment, the pair of hook-and-loop projections (3121, 3122) may be bent at an angle from the core portion (311).

[0132] According to one embodiment, the plurality of core portions (311) of the first core layer (310) may include a plurality of first core portions (311), and the second core layer (120) may include a plurality of second core portions (121) that are not connected to the plurality of bridge portions (312).

[0133] According to one embodiment, the plurality of first core layers (310) and the plurality of second core layers (120) may be alternately stacked in the vertical direction.

[0134] According to one embodiment, the hooking projections (3121, 3122) protruding from both sides of the outer end of one core portion (311) among the plurality of core portions (311) may be spaced apart from a pair of hooking projections (3121, 3122) protruding from both sides of the outer end of another core portion (311) among the plurality of core portions (311) adjacent to the one core portion (311).

[0135] According to one embodiment, the casing (30') may include a resin surrounding the rotor core (300) and at least a portion of each of the plurality of magnets (20).

[0136] A method for manufacturing a rotor (1) including a shaft (10), a plurality of magnets (20), a casing (30, 30'), and a rotor core (100, 300) according to one embodiment of the present disclosure may include a step (1110) of forming a rotor core (100a, 300a) by laminating a first core layer (110a, 310a) including a plurality of bridge portions (113a, 312a) and a second core layer (120) not including the plurality of bridge portions (113a, 312a). The method for manufacturing the rotor (1) may include a step of mounting the rotor core (100a, 300a) on a lower mold (210). The method for manufacturing the rotor (1) may include a step (1130) of mounting a plurality of magnets (20) on the rotor core (100a, 300a). The manufacturing method of the above rotor (1) may include a step (1140) of lowering an upper mold (220) provided with a punching section (222) to punch a plurality of bridge sections (113a, 312a) of a first core layer (110a, 310a).

[0137] According to one embodiment, the method for manufacturing the rotor (1) may include a step (1120) of inserting a shaft (10) into a through hole (101, 301) of the rotor core (100a, 300a) to connect the rotor core (100a, 300) and the shaft (10).

[0138] According to one embodiment, the method for manufacturing the rotor (1) may include a step (1150) of injecting and curing resin into a mold device (210, 220) to form a casing (30, 30') surrounding at least a portion of the rotor core (100, 300).

[0139] According to one embodiment, the plurality of bridge portions (113a, 312a) can be bent toward the first core layer (110a, 310a) by lowering the upper mold (220).

[0140] According to one embodiment, the first core layer (110a) includes a base portion (111) and a plurality of core portions (112) each connected to the base portion (111) through each of the plurality of bridge portions (113a), and the base portion (111) and the plurality of core portions (112) can be disconnected from each other by lowering the upper mold (220).

[0141] According to one embodiment, the first core layer (310a) includes a plurality of core parts (311) connected to each other through the plurality of bridge parts (312a), and the plurality of core parts (311) can be disconnected from each other by lowering the upper mold (220).

Claims

1. In a rotor (1) including a shaft (10), a plurality of magnets (20), a casing (30) and a rotor core (100), The above rotor core (100) is a plurality of first core layers (110); and Contains a plurality of second core layers (120), The above first core layer (110) is A base portion (111) through which the above shaft (10) penetrates; A plurality of core parts (112) spaced apart from each other along the circumferential direction of the above base part (111); and A rotor including a plurality of bridge portions (113, 113'), each of which extends from a corresponding core portion (112) among the plurality of core portions (112) toward the base portion (111) and is configured to bend toward the corresponding core portion (112).

2. In paragraph 1, Each of the above plurality of bridge sections (113) is a rotor that is bent vertically from the corresponding core section (112).

3. In paragraph 1, Each of the above plurality of bridge sections (113') is a rotor bent at an angle from the corresponding core section (112).

4. In any one of paragraphs 1 to 3, The plurality of core parts (112) of the first core layer (110) are a plurality of first core parts (112), The second core layer (120) is a rotor including a plurality of second core parts (121) that are not connected to the plurality of bridge parts (113, 113').

5. In any one of paragraphs 1 to 4, A rotor in which the plurality of first core layers (110) and the plurality of second core layers (120) are alternately laminated in the vertical direction.

6. In any one of paragraphs 1 to 5, A rotor, wherein each of the plurality of core parts (112) includes a pair of bending grooves (1122) arranged on each side of a bridge part (113) extending from each of the core parts (112).

7. In a rotor (1) including a shaft (10), a plurality of magnets (20), a casing (30') and a rotor core (300), The above rotor core (300) is A through hole (301) into which the above shaft (10) is inserted; a plurality of first core layers (310); and Contains a plurality of second core layers (120), The above first core layer (310) is A plurality of core parts (311) spaced apart from each other along the circumferential direction of the above through hole (301); and A rotor including a plurality of bridge portions (312) including a pair of bent catch projections (3121, 3122) that protrude in both directions in the circumferential direction toward the outer end (311a) of each core portion (311) among the plurality of core portions (311).

8. In paragraph 7, The above pair of catches (3121, 3122) are bent obliquely from the core part (311) of the rotor.

9. In paragraph 7 or 8, The plurality of core parts (311) of the first core layer (310) are a plurality of first core parts (311), The second core layer (120) is a rotor including a plurality of second core parts (121) that are not connected to the plurality of bridge parts (312).

10. In any one of paragraphs 7 to 9, A rotor in which the plurality of first core layers (310) and the plurality of second core layers (120) are alternately laminated in the vertical direction.

11. In any one of paragraphs 7 to 10, A rotor in which the protruding catches (3121, 3122) on both sides of the outer end of one core part (311) among the plurality of core parts (311) are spaced apart from a pair of protruding catches (3121, 3122) on both sides of the outer end of another core part (311) among the plurality of core parts (311) adjacent to the one core part (311).

12. A method for manufacturing a rotor (1) including a shaft (10), a plurality of magnets (20), a casing (30, 30') and a rotor core (100, 300), A step (1110) of forming a rotor core (100a, 300a) by laminating a first core layer (110a, 310a) including a plurality of bridge portions (113a, 312a) and a second core layer (120) not including the plurality of bridge portions (113a, 312a); A step of mounting the above rotor core (100a, 300a) on the lower mold (210); Step (1130) of mounting a plurality of magnets (20) on the above rotor core (100a, 300a); A method for manufacturing a rotor, comprising a step (1140) of lowering an upper mold (220) provided with a punching section (222) to punch the plurality of bridge sections (113a, 312a) of the first core layer (110a, 310a).

13. In paragraph 12, A method for manufacturing a rotor, wherein the plurality of bridge sections (113a, 312a) are bent toward the first core layer (110a, 310a) by lowering the upper mold (220).

14. In paragraph 12 or 13, The first core layer (110a) includes a base portion (111) and a plurality of core portions (112) each connected to the base portion (111) through each of the plurality of bridge portions (113a). A method for manufacturing a rotor, wherein the base portion (111) and the plurality of core portions (112) are disconnected from each other by lowering the upper mold (220).

15. In paragraph 12 or 13, The above first core layer (310a) includes a plurality of core parts (311) connected to each other through the plurality of bridge parts (312a), A method for manufacturing a rotor, wherein the plurality of core parts (311) are disconnected from each other by lowering the upper mold (220).

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