electric pump

Abstract

The present invention provides an electric pump including a housing, a gear portion arranged in the housing, a stator arranged corresponding to the gear portion, and a support member arranged between the gear portion and the housing, wherein the gear portion includes a first gear, a second gear arranged to correspond to the first gear, and a magnet arranged on the second gear, and the support member includes a first region that supports the first gear and a second region that protrudes from the first region and is inserted into the first gear.

Description

[Technical Field]

[0001] The present invention relates to an electric pump. [Background technology]

[0002] An electric oil pump (EOP) discharges oil at a constant pressure. Such an oil pump includes a housing, a gear unit disposed within the housing, and a motor that drives the gear unit. However, conventional electric oil pumps have a problem in that the gear unit and the motor unit are mechanically separated, resulting in a long axial length.

[0003] In addition, since the housing is made of plastic, heat generated by the gear section during operation can cause thermal deformation, which can lead to separation between the housing and the gear section, misalignment between the gears in the gear section, and reduced efficiency of the electric oil pump. Summary of the Invention [Problem to be solved by the invention]

[0004] The present invention aims to provide an oil pump that allows for a compact housing, prevents axial separation of the gear portion caused by thermal deformation of the housing, and stabilizes drive of the gear portion. [Means for solving the problem]

[0005] An embodiment may provide an electric pump including a housing, a gear portion arranged in the housing, a stator arranged corresponding to the gear portion, and a support member arranged between the gear portion and the housing, wherein the gear portion includes a first gear, a second gear arranged to correspond to the first gear, and a magnet arranged on the second gear, and the support member includes a first region that supports the first gear and a second region that protrudes from the first region and is inserted into the first gear.

[0006] Preferably, the second region may pass through the first gear. According to an embodiment, an electric pump can be provided that includes a housing, a gear portion arranged in the housing, a stator arranged corresponding to the gear portion, a cover arranged above the gear portion, and a support member arranged below the gear portion, wherein the support member includes a second region that passes axially through the gear portion and connects with the cover.

[0007] The housing may be coupled to the cover. The housing may include a lower surface supporting the gear portion and the support member, and a sidewall extending upward from the lower surface.

[0008] An embodiment can provide an electric pump including a molded member, a gear portion disposed within the molded member, a stator disposed corresponding to the gear portion, and a support member made of a metallic material disposed between the gear portion and the molded member, wherein the gear portion includes a first gear, a second gear disposed corresponding to the first gear, and a magnet disposed on the second gear, and at least a portion of the support member is disposed between a lower surface of the gear portion and one surface of the molded member.

[0009] The stator may be embedded in the molded member. The molding member may include a receiving portion in which the gear portion is disposed, and an upper surface of the molding member may be disposed higher than an upper stage of the stator.

[0010] The device may include a cover disposed above the gear portion, and at least a portion of the cover may be disposed in the receiving portion.

[0011] An embodiment may provide an electric pump including a housing, a gear portion arranged in the housing, a drive portion that drives the gear portion, and a support member arranged between the gear portion and the housing, wherein the gear portion includes a first gear and a second gear that rotates in correspondence with the first gear, the drive portion includes a magnet arranged on the second gear and a coil that is arranged in correspondence with the magnet, and the support member includes a first region that couples with the housing and a second region that is fixed to the first gear.

[0012] The housing may include a receiving portion in which the gear portion is disposed.

[0013] The support member may comprise aluminum. One region of the support member can pass through the gear portion in the axial direction, and the other region can support the gear portion in the axial direction.

[0014] The upper step of the support member may be positioned higher than the upper surface of the gear portion.

[0015] The maximum diameter of the support member may be greater than or the same as the outer diameter of the gear portion.

[0016] The gear portion may have a through hole formed therein in which the support member is disposed, and a protrusion protruding toward an axial center may be formed on an inner peripheral surface of the gear portion where the through hole is formed.

[0017] The support member includes a side surface that faces radially toward the inner circumferential surface of the gear portion, and a portion of the side surface of the support member may contact the protrusion, and another portion may be spaced apart from the inner circumferential surface of the gear portion. [Effects of the Invention]

[0018] According to the present invention, it is possible to prevent axial separation of the gear portion due to thermal deformation of the housing, reduce axial center error of the gears included in the gear portion, and ensure stable operation of the electric pump.

[0019] According to the present invention, by using electrical interaction between the gear section and the stator to provide the power required for pumping oil, a separate motor section can be omitted, thereby shortening the axial length of the electric pump and making the electric pump more compact. [Brief explanation of the drawings]

[0020] [Figure 1] 1 is a cross-sectional view schematically illustrating an electric pump according to an embodiment of the present invention. [Figure 2] FIG. 10 is a cross-sectional view schematically showing an electric pump according to another embodiment of the present invention. [Figure 3] FIG. 4 is a cross-sectional view showing an electric pump according to another embodiment of the present invention. [Figure 4] FIG. 10 is an exploded perspective view showing an electric pump according to another embodiment of the present invention. [Figure 5] FIG. 2 is a cross-sectional perspective view showing a cross section of a molded member and a stator. [Figure 6] FIG. 10 is a perspective view showing a state in which the gear portion and the support member are coupled together. [Figure 7] FIG. 2 is an exploded perspective view showing a first gear, a second gear, and a support member. [Figure 8] FIG. 10 is a plan view showing a state in which the gear portion and the support member are coupled together. [Figure 9] FIG. [Figure 10] FIG. [Figure 11] FIG. [Figure 12] FIG. 12 is an enlarged view of a part of FIG. [Figure 13] FIG. 10 is a plan view showing a state in which the first gear and the support member are coupled together. [Figure 14] FIG. 4 is a partial cross-sectional view of the electric pump shown in FIG. 3. [Figure 15] 10 is a graph comparing the comparative example and the working example with respect to the oil flow rate relative to the oil pressure. DETAILED DESCRIPTION OF THE INVENTION

[0021] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0022] The direction parallel to the rotation axis that serves as the reference for the rotational motion of the gear part is called the axial direction, the direction perpendicular to the axial direction centered on the rotation axis is called the radial direction, and the direction along a circle having a radial radius centered on the axial direction is called the circumferential direction.

[0023] FIG. 1 is a cross-sectional view schematically showing an electric pump according to an embodiment of the present invention.

[0024] Referring to FIG. 1, the electric pump 10 includes a housing 110 , a gear unit 120 , a stator 130 , a support member 140 , a cover 150 , and a power supply unit 160 .

[0025] The housing 110 and the cover 150 may form the outer shape of the electric pump 10. The stator 130 and the gear portion 120 may be disposed inside the housing 110. The housing 110 may be formed from a resin or plastic material.

[0026] The housing 110 may include a lower surface 111 and a side wall 112. In this case, the lower surface 111 can support the stator 130 and the gear portion 120 in the axial direction. The side wall 112 can surround the stator 130 from the outside. In this case, the gear portion 120 can be disposed inside the stator 130.

[0027] The gear unit 120 rotates through electrical interaction with the stator 130. The gear unit 120 may be disposed corresponding to or inside the stator 130. The gear unit 120 serves to pump the fluid and provides the power required for pumping.

[0028] The stator 130 is disposed in correspondence with the gear unit 120. A coil that forms a rotating magnetic field is wound around the stator 130, and induces electrical interaction with the gear unit 120 to induce rotation of the gear unit 120.

[0029] The support member 140 may be disposed between the gear portion 120 and the housing 110. In this case, the support member 140 may be fixed to the lower surface 101. An end of the support member 140 may penetrate the gear portion 120 and be coupled to the cover 150. The support member 140 may be made of a metal material. The support member 140 may rub against the lower surface of the gear portion 120 while the gear portion 120 is rotating. The support member 140 may reduce rotational friction of the gear portion 120 and prevent the gear portion 120 from separating in the axial direction. In addition, one side of the support member 140 may pass through the gear portion 120 in the axial direction and fix the rotation axis of the gear portion 120. 。

[0030] The cover 150 may be disposed on the upper side of the gear portion 120. The cover 150 may be coupled to the housing 110. The cover 150 may be formed of a metal material. In this case, the cover 150 may be made of the same material as the support member 140. The cover 150 may include aluminum.

[0031] The power supply unit 160 may be disposed on one side of the housing 110. The power supply unit 160 may be electrically connected to the stator 130 and may supply current to the stator 130. The power supply unit 160 may include a printed circuit board and electronic components mounted on the printed circuit board.

[0032] FIG. 2 is a cross-sectional view schematically showing an electric pump according to another embodiment of the present invention, FIG. 3 is a cross-sectional view showing an electric pump according to another embodiment of the present invention, and FIG. 4 is an exploded perspective view showing an electric pump according to another embodiment of the present invention.

[0033] 2 to 4, the electric pump 20 may include a mold member 210, a gear portion 220, a stator 230, a support member 240, a cover 250, and a power supply portion 260.

[0034] The mold member 210 covers the stator 230. At this time, the mold member 210 may be injection molded onto the stator 230. The mold member 210 may include a housing portion therein. The gear portion 220 is disposed in the housing portion. The housing portion may have a cylindrical shape. The diameter of the housing portion may be larger than the outer diameter of the gear portion 220.

[0035] The gear portion 220 may be disposed in a receiving portion of the mold member 210. The gear portion 220 may include a first gear 221, a second gear 222, and a magnet 223. The second gear 222 may be disposed outside the first gear 221. The magnet 223 may be disposed on the outer circumferential surface of the second gear 222. There may be a plurality of magnets 223. The magnets 223 may be disposed along the circumferential direction.

[0036] The stator 230 is disposed inside the mold member 210. The stator 230 is disposed corresponding to the gear unit 220. The stator 230 is electrically connected to the power supply unit 260, and when a current is supplied from the power supply unit 260, an electrical interaction may be induced between the stator 230 and the magnet 223.

[0037] The support member 240 is disposed between the gear unit 220 and the molded member 210. One surface of the support member 240 contacts the molded member 210. In this case, one surface of the support member 240 may be fixed to the molded member 210. An end of the support member 240 may penetrate the gear unit 220. The end of the support member 240 may be coupled to the cover 250. The support member 240 may be made of a metallic material. When the gear unit 220 is driven by electrical interaction between the stator 230 and the gear unit 220, the support member 240 may slide with the gear unit 220. Since the support member 240 is made of a metallic material, it has excellent sliding properties with the gear unit 220. Furthermore, it is possible to prevent axial separation between the gear unit 220 and the molded member 210. In addition, the support member 240 fixes the rotation axis of the gear unit 220, thereby enabling the gear unit 220 to drive more stably.

[0038] The cover 250 may be disposed above the gear portion 220 and coupled to the upper section of the mold member 210. The cover 250 may be made of a metal material. The cover 250 may include an intake port (not shown) and an exhaust port (not shown). The intake port (not shown) and the exhaust port (not shown) may guide fluid to be smoothly drawn in and exhausted by the gear portion 220.

[0039] The power supply unit 260 may be disposed on one side of the molded member 210. The power supply unit 260 may be electrically connected to the stator 230 and may supply current to the stator 230. The power supply unit 260 may include a printed circuit board and electronic components mounted on the printed circuit board.

[0040] FIG. 5 is a cross-sectional perspective view showing a cross section of the molded member and the stator.

[0041] 5, the stator 230 may include a stator core 231, a coil 232 wound around the stator core 231, and an insulator 233 disposed between the stator core 231 and the coil 232. In this case, the coil 232 may be connected to a power supply unit 260. The stator 230 is embedded in the molded member 210.

[0042] The molded member 210 may cover the stator core 231, the coils 232, and the insulators 233. In this case, the molded member 210 may be coupled to the stator 230 by an injection molding method. The injection molding method may be an insert injection molding method. In this case, the molded member 210 may be formed of a resin or plastic material. For example, the molded member 210 may be formed of a thermally conductive plastic material. Examples of thermally conductive plastics include pellet-type resin, heat dissipation resin, PPA (Polyphtalamide) resin, CNT (Carbon NanoTube), etc.

[0043] A cover 250 may be disposed on an upper surface 210A of the molded member 210. In this case, the upper surface 210A of the molded member 210 may be disposed higher than the upper stage of the stator 230. At least one fastening hole 210H may be formed in the upper surface 210A of the molded member 210. In addition, a screw thread for coupling a fastening member may be formed in the fastening hole 210H. In this case, the fastening hole 210H may be coupled to the cover 250 by the fastening member.

[0044] The mold member 210 may form a receiving portion S. The gear portion 220 may be disposed in the receiving portion S. The receiving portion S may have a cylindrical shape. The axial length of the receiving portion S may be greater than the axial length of the gear portion 220. The diameter of the receiving portion S may be greater than the outer diameter of the gear portion 220.

[0045] The upper side of the storage section S can be closed by a cover 250.

[0046] The edge of the cover 250 is bonded to the upper surface 210A of the mold member 210. -2 The center of the 50 is the gear part 220 The cover 250 protrudes to the side and is disposed in the receiving portion S. At this time, the center portion of the cover 250 can fix the upper part of the gear portion 220. The receiving portion S can be connected to an intake port (not shown) and an exhaust port (not shown) of the cover 250. At this time, the intake port (not shown) and the exhaust port (not shown) can be formed to be partitioned in space.

[0047] FIG. 6 is a perspective view showing the gear portion and the support member connected together, FIG. 7 is an exploded perspective view showing the first gear, the second gear and the support member, and FIG. 8 is a plan view showing the second gear and the support member.

[0048] In this embodiment, for convenience of explanation, the description has been given with reference to the gear portion 220 and the support member 240 shown in FIG. 3, but the shapes and functions of the gear portion 220 and the support member 240 described in this embodiment can also be applied to the gear portion 120 and the support member 140 shown in FIGS. 1 and 6.

[0049] 6, the support member 240 axially supports the gear portion 220. The support member 240 also passes through the gear portion 220 to fix the rotation axis of the gear portion 220. To this end, the support member 240 may include a first region 241 and a second region 242.

[0050] The first region 241 is disposed below the gear portion 220. In this case, the first region 241 can support the lower surface of the gear portion 220. The first region 241 can be fixed to the mold member 210. The first region 241 can be disk-shaped. A diameter D2 of the first region 241 can be equal to or greater than an outer diameter D1 of the gear portion 220. Meanwhile, although not shown in the drawings, the diameter of the first region can be smaller than the outer diameter of the gear portion, and the edge of the gear portion can be spaced apart from the mold member.

[0051] The second region 242 may protrude from the first region 241. The second region 242 may penetrate the first gear 221. In this case, the second region 242 may be disposed at the rotation axis of the first gear 221. The second region 242 may be a cylindrical member extending in the axial direction. In this case, the diameter of the second region 242 may be smaller than the diameter of the inner circumferential surface of the first gear 221.

[0052] Referring to FIG. 7, the first gear 221 may be disposed inside the second gear 222, and the second region 242 may be disposed inside the first gear 221. The second region 242 may pass through the first gear 221 in the axial direction. In this case, the axial length of the second region 242 may be greater than the axial length of the gear portion 220. An end of the second region 242 may be disposed higher than the upper surface of the first gear 221. Then, the second region 242 The end of the can be coupled to the cover 250 .

[0053] Referring to FIG. 8, the first gear 221 may have N outer lobes 2211 formed in the circumferential direction and extending radially outward from the axial center. Meanwhile, the second gear 222 may have N+1 inner lobes 2221 formed in the radially inward direction. In this case, the outer lobes 2211 may be formed to engage with the inner lobes 2221. As the first gear 221 rotates, the second gear 222 rotates at a rotation ratio of (N+1) / N. The gear unit 220 has a certain eccentric structure when the first gear 221 rotates. This eccentricity creates a space between the first gear 221 and the second gear 222 that can transport fluid (oil). That is, when the first gear 221 rotates, the portion that increases in volume draws in surrounding fluid due to a pressure drop, and the portion that decreases in volume discharges fluid due to an increase in pressure.

[0054] The gear unit 220 generates electrical interaction with the stator 330 to pump the oil and provide the power required for pumping. Therefore, the electric pump according to the present invention can omit a separate motor unit, thereby reducing the axial length of the electric pump.

[0055] 9 is a perspective view showing the support member, FIG. 10 is a plan view showing the support member, FIG. 11 is a side view showing the support member, and FIG. 12 is an enlarged view of a portion of FIG. 11.

[0056] 9, the support member 240 may include a first region 241 and a second region 242 that protrudes upward from an upper surface of the first region 241. In this case, the first region 241 and the second region 242 may be integrally formed. The support member 240 may include aluminum. In this case, the cover 250 may be made of the same material as the support member 240.

[0057] The first region 241 may include a first surface 241A and a second surface 241B. The first surface 241A and the second surface 241B may be arranged in the axial direction. At this time, the first surface 241A is arranged toward the gear portion 220, and the second surface 241B is arranged toward the molding member 210. The first surface 241A contacts the gear portion 220, and the second surface 241B contacts the molding member 210. At this time, while the gear portion 220 rotates, friction may occur between the contact portion of the first surface 241A and the gear portion 220. A diameter D2 of the first region 241 may be greater than or equal to the outer diameter of the gear portion 220.

[0058] The first region 241 may be disk-shaped. In this case, the first region 241 may have a first thickness T1 in the axial direction. In this case, the first thickness T1 may be equal to the distance between the molded member 210 and the cover 250 disposed in the receiving portion S minus the axial length of the gear portion 220. In this case, the height of the gear portion 220 in the axial direction can be adjusted according to the first thickness T1 of the first region 241. In addition, by adjusting the first thickness T1 of the first region 241, it is possible to prevent separation between the molded member 210, the gear portion 220, and the cover 250 disposed in the axial direction.

[0059] The second region 242 extends from the first region 241. The second region 242 may be disposed on the first surface 241A. The second region 242 may be disposed eccentrically with respect to the center of the first surface 241A. The shortest distance from a point P1 at one edge of the first surface 241A to the second region 242 may be different from the shortest distance from another point P2 at another edge of the upper surface of the first region 241 to the second region 242.

[0060] The second region 242 may include a first portion 2421 and a second portion 2422. The first portion 2421 may extend from the first region 241. The first portion 2421 may be disposed inside the first gear 221. In this case, a diameter D3 of the first portion 2421 may be smaller than or equal to the diameter of the inner circumferential surface of the first gear 221. In this manner, the first portion 2421 is disposed on a rotation axis that serves as a reference for the rotational motion of the first gear 221, and can support the radial movement of the gear portion 220.

[0061] The second portion 2422 may extend from an end of the first portion 2421. The second portion 2422 may be disposed above an upper surface of the first gear 221. The second portion 2422 may be coupled to the cover 250. In this case, a groove corresponding to the shape of the second portion 2422 may be formed in the cover 250, and the second portion 2422 may be disposed in the groove. The diameter D4 of the second portion 2422 may be smaller than the diameter D3 of the first portion 2421. According to one embodiment, the ratio of the diameter D3 of the first portion 2421 to the diameter D3 of the second portion 2422 may be 0.5 to 0.8. The support member 240 may support the radial movement of the gear portion 220 while the gear portion 220 is driven, and may be coupled to the cover 250 to increase the fixing force.

[0062] The axial length L of the second region 242 is equal to the sum of the axial lengths of the first portion 2421 and the second portion 2422. In this case, the first portion 2421 may have a first axial length L1, and the second portion 2422 may have a second axial length L2. In this case, the first length L1 may be greater than the second length L2. According to an embodiment, the ratio of the second length L2 to the first length L1 may be 0.15 to 0.4.

[0063] Meanwhile, according to another embodiment of the present invention, although not shown in the drawings, the axial length L of the second region 242 may be smaller than the axial length of the gear portion 220. In this case, the upper part of the second region 242 may be positioned lower than the upper surface of the gear portion 220. In addition, the upper part of the second region 242 may be spaced apart from the cover 250.

[0064] 12, the upper edge of the first portion 2421 may be tapered. Also, the upper edge of the second portion 2422 may be tapered. In addition, the second region 242 may include a step 2423 connecting the first portion 2421 and the second portion 2422.

[0065] FIG. 13 is a plan view showing a state in which the support member 140 and the first gear are coupled together.

[0066] Referring to Figure 13, first gear 221The first gear may have a first width W that is the minimum width based on the radial direction. 221 inner diameter and first gear 221 The first width W1 may be the shortest distance between the dedendum circle of the first gear and the dedendum circle of the first gear. The first width W1 may be smaller than the diameter D3 of the first gear. For example, the first width W1 may be 2 to 4.5 mm, and the diameter D3 of the first gear 2421 may be 4.5 to 6.5 mm. In this case, the first width W1 and the diameter D3 of the first gear 2421 may vary depending on the size of the electric pump. The ratio of the first width W1 to the diameter D3 of the first gear 2421 may be 0.3 to 1. In this case, the lower the ratio of the first width W1 to the diameter D3 of the first gear 2421, the shorter the distance between the dedendum circle of the first gear and the dedendum circle of the first gear. 221 On the other hand, if the ratio of the first width W1 to the diameter D3 of the first portion 2421 becomes high, the diameter of the first portion 2421 cannot be ensured sufficiently, and the mechanical rigidity of the support member 240 may decrease.

[0067] FIG. 14 is a partial cross-sectional view of the electric pump shown in FIG.

[0068] 14, the first gear 221 may include a lower surface facing the support member 240 and an upper surface facing the cover 250. The first gear 221 may have a through-hole 221H formed therein, penetrating the upper and lower surfaces. A rotation axis RA, which is a reference for the rotational movement of the first gear 221, may be disposed in the through-hole 221H. The first portion 2421 may be disposed in the through-hole 221H. The first portion 2421 may include a side surface 2421A facing the inner circumferential surface of the first gear 221. The diameter of the through-hole 221H may be larger than the diameter of the first portion 2421, and the side surface 2421A may be larger than the diameter of the first portion 2421. 2421A can be spaced apart from the inner circumferential surface of the first gear 221.

[0069] The first gear 221 may include a protruding portion 2212 that protrudes toward the rotation axis RA. The protruding portion 2212 may be disposed on the inner circumferential surface of the first gear 221. In this case, the protruding portion 2212 may include a protruding surface 221A that contacts the side surface 2421A of the first portion 2421.

[0070] The side surface 2421A of the first portion 2421 may include a first part 2421A1, a second part 2421A2, and a third part 2421A3.

[0071] The first part 2421A1 may contact the protruding surface 221A. The first part 2421A1 may be spaced apart from the first region 241. The second part 2421A2 may be disposed between the first region 241 and the first part 2421A1. At this time, the second part 2421A2 may be spaced apart from the first gear 221. The second part 2421A2 may have a longer axial length than the first part 2421A1. The third part 2421A3 may be disposed between the first part 2421A1 and the second part 2422. At this time, the third part 2421A3 may be spaced apart from the first gear 221. Meanwhile, the cover 250 may include a protrusion 251 protruding between the third part 2421A3 and the first gear 221. A groove 250G may be formed on the inner side of the protrusion 251 of the cover 250. At this time, the second portion 2422 may be disposed in the groove 250G. The axial length of the groove 250G may be formed to be longer than the axial length of the second portion 2422. At this time, the upper part of the second portion 2422 may be spaced apart from the cover 250.

[0072] The cover 250 may include a seating surface 250A disposed between the groove 250G and the protrusion 251. At this time, the seating surface 250A may come into contact with the step 2423. In this manner, the cover 250 includes a structure for being coupled and fixed to the support member 240, thereby increasing the fixing force of the support member 240.

[0073] FIG. 15 is a graph comparing the comparative example and the working example with respect to the oil flow rate relative to the oil pressure.

[0074] In the example shown in Fig. 15, we measured the change in oil flow rate versus oil pressure of an electric pump including a housing, gear section, stator, support member, and cover as shown in Fig. 3. The electric pump of the example has a structure in which power is generated via the gear section, and oil is pumped from the gear section.

[0075] In Comparative Example 1, the change in oil flow rate relative to oil pressure was measured for a conventional electric pump in which the motor and pump sections were mechanically separated. The electric pump in Comparative Example 1 has a structure in which power generated by the motor section is transmitted to the pump section, causing the pump section to operate.

[0076] In Comparative Example 2, the change in oil flow rate relative to the oil pressure of an electric pump in which the support member was omitted from the structure of Figure 3 was measured. In this case, the electric pump of Comparative Example 2 may have the same configuration as the electric pump used in the Examples, except that the support member was omitted.

[0077] 15, it can be seen that the oil flow rate in Comparative Example 2 decreases more rapidly as the oil pressure increases compared to Comparative Example 1. Therefore, it can be seen that the oil flow rate in Comparative Example 2 decreases more rapidly depending on the oil pressure than in a conventional electric pump in which the motor and pump are mechanically separated. This confirms that although an electric pump including a gear unit that functions as a motor and pump unit can shorten its axial length, axial separation occurs between the gear unit and the housing, resulting in hydraulic loss.

[0078] On the other hand, it can be seen that the oil flow rate of the Example decreases relatively little even when the oil pressure increases compared to Comparative Example 2. It can also be seen that the amount of decrease in the flow rate of the Example is similar to that of Comparative Example 1. That is, it can be seen that the Example has a similar structure to Comparative Example 2, but there is no significant difference in the oil pumping performance between Comparative Example 1 and the Example. As such, the electric pump according to the present invention can maintain oil pumping performance by preventing axial separation between the gear unit and the housing while reducing the axial length and size.

[0079] Although the above embodiment has been described using an electric pump as an example, the present invention is not limited to this and can be used in various devices such as vehicles and home appliances.

Claims

1. A molded member, a gear portion disposed on the mold member; a stator disposed corresponding to the gear portion; a support member disposed between the gear portion and the molding member, the gear unit includes a first gear, a second gear arranged to correspond to the first gear, and a magnet arranged on the second gear, the support member includes a first region that supports the first gear and a second region that protrudes from the first region and is inserted into the first gear, The first region is located between the first gear and the molding member in the axial direction, and the first region is in contact with both the first gear and the molding member.

2. The electric pump according to claim 1 , wherein the second region passes through the first gear.

3. a cover disposed above the gear portion, The electric pump according to claim 1 , wherein the second region passes through the gear portion in the axial direction and is coupled to the cover.

4. The electric pump according to claim 3 , wherein the molded member is coupled to the cover.

5. The molding member is a lower surface that supports the gear portion and the support member; The electric pump according to claim 4 , further comprising: a side wall extending upward from the lower surface.

6. the molding member includes a receiving portion in which the gear portion is disposed, The electric pump according to claim 1 , wherein an upper surface of the molded member is positioned higher than an upper stage of the stator.

7. a cover disposed above the gear portion, The electric pump according to claim 6 , wherein at least a portion of the cover is disposed in the housing portion.

8. a drive unit that drives the gear unit, The electric pump according to claim 1 , wherein the driving portion includes a magnet disposed on the second gear and a coil disposed corresponding to the magnet.

Images