Brushless direct-current water pump

Abstract

The utility model provides a brushless direct-current water pump. The brushless direct-current water pump comprises a shell, a pump head, an impeller and a rotor assembly. A rotor cavity is formed in the shell, and an opening of the rotor cavity faces the head end of the shell; a water inlet is formed in the pump head, the pump head is fixed to the head end of the shell, the water inlet is opposite to the shell, and an impeller cavity communicated with the rotor cavity is formed between the head end of the shell and the pump head; the rotor assembly is arranged in the rotor cavity, the output end of the rotor assembly extends into the impeller cavity, the impeller is arranged at the output end of the rotor assembly, and the rotor assembly drives the impeller to rotate so as to form high-pressure water flow in the impeller cavity; the impeller comprises a plurality of blades, and the radial size of the head portion of each blade is smaller than that of the tail portion of each blade. The utility model can reduce the phenomenon that air at the bottom of the impeller rotates and traps air.

Description

Technical Field

[0001] This utility model relates to the field of water pumps, and more specifically, to a brushless DC water pump. Background Technology

[0002] A brushless DC water pump is a type of pump that uses a brushless DC motor as its drive source and is widely used in various applications requiring precise control of fluid transport. Existing brushless DC water pumps typically include a pump casing, impeller, rotor assembly, and stator assembly. The stator and rotor assemblies work together to drive the impeller to rotate within the impeller cavity of the pump casing, creating a high-pressure water flow. However, in existing impellers, the blades at different axial positions have the same radial dimension. This causes air to swirl and become trapped at the bottom of the impeller during startup, resulting in relatively low pumping efficiency. Utility Model Content

[0003] The technical problem to be solved by this utility model is to provide a new brushless DC water pump that addresses the problem of air swirls and traps air at the bottom of the impeller of the aforementioned brushless DC water pump.

[0004] The technical solution of this utility model to solve the above-mentioned technical problems is to provide a brushless DC water pump, including a housing, a pump head, an impeller, and a rotor assembly; the housing has a rotor cavity, and the opening of the rotor cavity faces the front end of the housing; the pump head has a water inlet, the pump head is fixed to the front end of the housing, and the water inlet faces away from the housing, and an impeller cavity communicating with the rotor cavity is formed between the front end of the housing and the pump head; the rotor assembly is installed in the rotor cavity, and the output end of the rotor assembly extends into the impeller cavity; the impeller is installed at the output end of the rotor assembly, and the rotor assembly drives the impeller to rotate to form a high-pressure water flow in the impeller cavity; the impeller includes multiple blades, and the radial dimension of the front end of each blade is smaller than the radial dimension of the tail end.

[0005] As a further improvement of this utility model, the water inlet, impeller cavity and rotor cavity are coaxially arranged, the axial length of the largest radial dimension portion on the blade is less than two-thirds and greater than one-third of the axial length of the blade, and the head of the impeller extends out of the pump head through the water inlet.

[0006] As a further improvement of this utility model, the radial dimension of the tail of each blade in the impeller is smaller than the radius of the impeller cavity, the radial dimension of the middle part of the blade is slightly smaller than the radius of the inlet, the free end of the blade is inclined toward the central axis of the impeller, and the inlet surrounds the middle section of the impeller, and the part of the blade that is inclined toward the central axis of the impeller protrudes out of the pump head.

[0007] As a further improvement of this utility model, the outer casing includes a water outlet pipe, with the inlet of the water outlet pipe located at the front end of the outer casing and connected to the impeller cavity, and the outlet of the water outlet pipe located at the rear end of the outer casing.

[0008] As a further improvement of this utility model, the pump head has a slope at the position facing the inlet of the outlet pipe, and the slope guides the high-pressure water flow in the impeller cavity into the inlet of the outlet pipe.

[0009] As a further improvement of this utility model, the pump head has a first groove, the water inlet is located at the bottom of the first groove, and the pump head is fixed to the front end of the outer casing with the first groove facing the outer casing. The impeller cavity is formed by the first groove.

[0010] As a further improvement of this utility model, the bottom of the rotor cavity has a bearing seat, and the front end of the outer shell has a second groove arranged around the opening of the rotor cavity; the rotor assembly includes a rear bearing, a front bearing, a front bearing plate, a rotating shaft, and a rotor body. The rear bearing is installed in the bearing seat, the front bearing is installed on the front bearing plate, the front bearing plate is installed in the second groove, and the rotor body is installed between the front bearing and the rear bearing through the rotating shaft, and the front part of the rotating shaft constitutes the output end of the rotor assembly.

[0011] As a further improvement of this utility model, the brushless DC water pump includes a stator assembly and a control circuit board. The housing includes a stator cavity that is isolated from the rotor cavity. The opening of the stator cavity is located at the tail end of the housing. The stator assembly and the control circuit board are respectively installed in the stator cavity, and the stator assembly is located in the part of the stator cavity surrounding the rotor cavity.

[0012] As a further improvement of this utility model, the outer wall of the first end of the housing has a plurality of axially arranged nut seats, and the plurality of nut seats are evenly distributed along the circumference of the housing; the pump head has a plurality of first fixing holes corresponding to the nut seats, and the pump head is fixed to the first end of the housing by a plurality of screws passing through the first fixing holes and threadedly connected to the nuts in the nut seats of the housing.

[0013] As a further improvement of this utility model, the first end of the outer shell is formed with a flange, and the flange has a plurality of second fixing holes; a plurality of nut seats are respectively connected to the side of the flange facing away from the pump head, each nut seat includes a hexagonal prism groove with an opening located at the end facing away from the pump head and communicating with the second fixing hole, and the cross-sectional dimensions of the hexagonal prism groove are adapted to the dimensions of the nut.

[0014] The present invention has the following beneficial effects: by making the radial dimension of the front part of the blades in the impeller smaller than the radial dimension of the tail part, some water flow is pushed from the front part of the impeller to the tail part of the impeller during the impeller rotation, thereby reducing the phenomenon of air swirl and trapping at the bottom of the impeller. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the brushless DC water pump provided in this embodiment of the utility model.

[0016] Figure 2 This is an exploded structural diagram of the brushless DC water pump provided in this embodiment of the utility model.

[0017] Figure 3 This is a schematic diagram illustrating the working principle of the brushless DC water pump provided in this embodiment of the utility model.

[0018] Figure 4 This is a schematic diagram of the head end of the brushless DC water pump provided in this embodiment of the present invention.

[0019] Figure 5 This is a schematic diagram of the outer casing of the brushless DC water pump provided in this embodiment of the utility model. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0021] Those skilled in the art will understand that hardware manufacturers may use different names to refer to the same component. This specification and claims do not distinguish components by differences in name, but by differences in function. The term "comprising" as used throughout this specification and claims is an open-ended term and should be interpreted as "comprising but not limited to". "Approximately" means that within an acceptable margin of error, those skilled in the art can solve the technical problem and substantially achieve the technical effect within a certain margin of error.

[0022] In the description of the application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "horizontal", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present utility model.

[0023] In the description of this application, unless otherwise expressly specified and limited, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance; the term "multiple" refers to two or more; unless otherwise specified or explained, the terms "connected," "fixed," etc., should be interpreted broadly. For example, "connected" can be a fixed connection, a detachable connection, an integral connection, or an electrical connection; "connected" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0024] like Figure 1 , Figure 2 The diagram shown is a schematic of a brushless DC water pump provided in this embodiment of the invention. This brushless DC water pump can be applied to atomizers, air purifiers, humidifiers, etc. The brushless DC water pump of this embodiment includes a pump housing 10, an impeller 20, and a rotor assembly 30, wherein the rotor assembly 30 is installed inside the pump housing 10. Similar to existing brushless DC water pumps, the above-mentioned brushless DC water pump also includes a stator assembly, a control circuit board, etc., and the pressurized delivery of water can be achieved through the rotation of the rotor assembly 30.

[0025] The aforementioned pump housing 10 includes an outer shell 11 and a pump head 12. Both the outer shell 11 and the pump head 12 can be made of a corrosion-resistant, high-strength, and easily processed polymer material (such as plastic). Figure 3 As shown, the housing 11 has a rotor cavity 111 inside, and the opening of the rotor cavity 111 faces the front end of the housing 11. The pump head 12 has a water inlet 121, and similar to existing brushless DC water pumps, the diameter of the water inlet 121 is smaller than the diameter of the rotor cavity 111. The pump head 12 is fixed to the front end of the housing 11, and the water inlet 121 faces away from the housing 11. An impeller cavity 113 communicating with the rotor cavity 111 is formed between the front end of the housing 11 and the pump head 12. Similar to existing brushless DC water pumps, the diameter of the impeller cavity 113 is larger than the diameter of the rotor cavity 111. Specifically, the pump head 12 can be fixed to the front end of the housing 11 by clips, adhesive, screws, etc. In addition, to improve the sealing performance, a sealing ring or the like can also be provided between the pump head 12 and the housing 11.

[0026] The rotor assembly 30 is installed within the rotor cavity 111, and its output end extends into the impeller cavity 113. Similar to existing brushless DC water pumps, the rotor assembly 30 includes a rotor body 32 and a shaft 33. The rotor body 32 may include multiple permanent magnets arranged in alternating polarities. The shaft 33 passes through the center of the rotor body 32, and its front portion extends into the impeller cavity 113, forming the output end of the rotor assembly 30. The impeller 20 is installed at the output end of the rotor assembly 30 (i.e., the portion of the shaft 33 extending into the impeller cavity 113), and is driven by the rotor assembly 30 to rotate, thereby creating a high-pressure water flow (i.e., a water flow with a pressure greater than that at the position when the impeller 20 is stationary) within the impeller cavity 113. The impeller 20 described above includes multiple blades, and the radial dimension of the tip (i.e. the end away from the housing 11) of each blade is smaller than the radial dimension of its tail (i.e. the end close to the housing 11). For example, the radial dimension of the tail of the blade is larger than the radius of the rotor cavity 111, while the radial dimension of the tip of the blade is smaller than the radius of the inlet 121.

[0027] The aforementioned brushless DC water pump reduces the phenomenon of air swirl and entrapment at the bottom of the impeller 20 by making the radial dimension of the front end of the blades in the impeller 20 smaller than that of the rear end. This is achieved by having the front end of the impeller 20 push a portion of the water flow towards the rear end of the impeller 20 during its rotation.

[0028] like Figure 3 As shown, in one embodiment of this utility model, the inlet 121, impeller cavity 113, and rotor cavity 111 are coaxially arranged. The radial dimension of the tail of each blade in the impeller 20 is slightly smaller than the radius of the impeller cavity 113, and the radial dimension of the middle part of the blade is slightly smaller than the radius of the inlet 121 (a transition slope may also be present between the tail and the middle part). The free end of the blade is inclined towards the central axis of the impeller 20. Furthermore, the head of the impeller 20 extends out of the pump head 12 via the inlet 121, that is, the inlet 121 surrounds the middle section of the impeller 20, and the inclined part of the free end of the blade protrudes out of the pump head 12. With the above structure, while ensuring that the impeller 20 generates a large thrust on the water in the impeller cavity 113 when rotating, the problem of air trapping at the bottom of the impeller can be better solved. In particular, on each blade of the impeller 20, the axial length of the largest radial dimension portion (corresponding to the tail of the impeller) is less than two-thirds and greater than one-third of the axial length of the blade, such as... Figure 3 As shown.

[0029] In one embodiment of this utility model, the aforementioned housing 11 includes a water outlet pipe 114. The inlet of the water outlet pipe 114 is located at the first end of the housing 11 and communicates with the impeller cavity 113, while the outlet of the water outlet pipe 114 is located at the last end of the housing 11, and the outlet of the water outlet pipe 114 constitutes the water outlet of the brushless DC water pump. Water flowing into the impeller cavity 113 from the inlet 121 is pushed by the impeller 20 and flows through the inlet into the water outlet pipe 114, and flows out from its outlet. That is, the inlet 121 and the outlet of the brushless DC water pump are located at its first and last ends, respectively. In use, the brushless DC water pump can simply be placed in the water body with the inlet 121 facing downwards, without the need to connect a separate water pipe to the inlet 121, which also facilitates the connection of an external water pipe to the outlet.

[0030] In particular, to avoid the water outlet pipe 114 affecting the internal structure of the brushless DC water pump, the water outlet pipe is located on the outside of the housing 11, for example, protruding from the outer wall of the housing 11.

[0031] like Figure 3 As shown, the pump head 12 has a slope 122 at the inlet facing the outlet pipe 114, and this slope 122 guides the high-pressure water flow in the impeller cavity 113 into the inlet of the outlet pipe 114. That is, along the impeller 20... Figure 4 When rotating in the direction indicated by the middle arrow, external water is drawn into the impeller chamber 113, and the impeller 20 further pushes the water in the impeller chamber 113 onto the slope 122, and flows along the slope 122 into the outlet pipe 114, as shown. Figure 3 As indicated by the arrow in the diagram. The above structure avoids the loss of kinetic energy caused by water flow impacting the side wall of the impeller cavity 113, resulting in higher pumping efficiency of the brushless DC water pump. It also further reduces the situation where air accumulates at the bottom of the impeller cavity 113 and cannot be discharged.

[0032] In one embodiment of this utility model, the pump head 12 has a first groove, the water inlet 121 is located at the bottom of the first groove, and the pump head 12 is fixed to the front end of the housing 11 with the first groove facing the housing 11. The impeller cavity 113 is formed by the first groove. That is, the impeller cavity 113 is formed inside the pump head 12. The above structure facilitates the processing and assembly of the pump housing 10. In practical applications, the impeller cavity 113 can also be formed by the groove at the front end of the housing 11, or by a combination of the groove at the front end of the housing 11 and the groove of the pump head 12.

[0033] In one embodiment of this utility model, the bottom of the rotor cavity 111 has a bearing seat, and the front end of the outer shell has a second groove 115 surrounding the opening of the rotor cavity 111. Accordingly, in addition to the rotating shaft 33 and the rotor body 32, the rotor assembly also includes a rear bearing 31, a front bearing, and a front bearing plate 34, wherein the rear bearing 31 is installed in the bearing seat, the front bearing is installed on the front bearing plate 34, and the front bearing plate 34 is installed in the second groove 115. The rotor body 32 is installed between the front bearing and the rear bearing 31 via the rotating shaft 33, and the head of the rotating shaft 33 (i.e., the part protruding into the impeller cavity 113) constitutes the output end of the rotor assembly 30.

[0034] Furthermore, the aforementioned brushless DC water pump also includes a stator assembly 40 and a control circuit board 50. Correspondingly, the housing 11 includes a stator cavity 112 isolated from the rotor cavity 111, with the opening of the stator cavity 112 located at the rear end of the housing 11. The stator assembly 40 and the control circuit board 50 are respectively installed within the stator cavity 112, with the stator assembly 40 located within the portion of the stator cavity 112 surrounding the rotor cavity 111. Similar to existing brushless DC water pumps, the coils in the stator assembly 40 are electrically connected to the control circuit board 50. The control circuit board 50, by supplying alternating current to the coils of the stator assembly 40, causes the stator assembly 40 to generate an alternating magnetic field. This causes the rotor body 32 of the rotor assembly 30 to rotate under the influence of the alternating magnetic field, thereby driving the impeller 20 to rotate. Both the stator assembly 40 and the control circuit board 50 can employ techniques conventional in the art, which will not be elaborated upon here. In particular, to improve waterproofing performance, the stator cavity 112 can be encapsulated with potting compound.

[0035] like Figure 5 As shown, to improve the bonding strength between the housing 11 and the pump head 12, in one embodiment of this utility model, the outer wall of the first end of the housing 11 has multiple axially arranged nut seats 116, and the multiple nut seats 116 are evenly distributed along the circumference of the housing 11. Correspondingly, the pump head 12 has multiple first fixing holes 123 corresponding to the nut seats 116. The pump head 12 is fixed to the first end of the housing 11 by multiple screws 13, and each screw 13 passes through the first fixing hole 123 from above the pump head 12 and is threadedly connected to the nut 15 in the nut seat 116 of the housing 11. The pump head 12 is threadedly connected to the nut in the nut seat 116 of the housing 11 by passing through the first fixing hole 123. In practical applications, internal threads can also be machined on the inner wall of the nut seat 116, and the screw 13 can be directly threaded onto the internal thread of the nut seat 116.

[0036] In one embodiment of the present invention, the first end of the outer shell 11 is formed with a flange 117, and the flange 117 has a plurality of second fixing holes 118; a plurality of nut seats 116 are respectively connected to the side of the flange 117 facing away from the pump head 12, and each nut seat 116 includes a hexagonal prism groove with an opening located at the end facing away from the pump head 12 and communicating with the second fixing hole 118, and the cross-sectional dimensions of the hexagonal prism groove are adapted to the dimensions of the nut.

[0037] The above description is merely a preferred embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the scope of the claims.

Claims

1. A brushless DC water pump, characterized in that, It includes a housing, a pump head, an impeller, and a rotor assembly; the housing has a rotor cavity, and the opening of the rotor cavity faces the front end of the housing; The pump head has a water inlet, the pump head is fixed to the front end of the housing, and the water inlet faces away from the housing. An impeller cavity is formed between the front end of the housing and the pump head, which is connected to the rotor cavity. The rotor assembly is installed in the rotor cavity, and the output end of the rotor assembly extends into the impeller cavity. The impeller is installed at the output end of the rotor assembly and is driven by the rotor assembly to rotate to form a high-pressure water flow in the impeller cavity. The impeller includes multiple blades, and the radial dimension of the head of each blade is smaller than the radial dimension of the tail.

2. The brushless DC water pump according to claim 1, characterized in that, The inlet, impeller cavity, and rotor cavity are coaxially arranged. The axial length of the largest radial dimension portion on the blade is less than two-thirds and greater than one-third of the axial length of the blade. The head of the impeller extends out of the pump head via the inlet.

3. The brushless DC water pump according to claim 2, characterized in that, The radial dimension of the tail of each blade in the impeller is smaller than the radius of the impeller cavity, the radial dimension of the middle part of the blade is smaller than the radius of the inlet, the free end of the blade is inclined toward the central axis of the impeller, and the inlet surrounds the middle section of the impeller. The part of the blade that is inclined toward the central axis of the impeller protrudes outside the pump head.

4. The brushless DC water pump according to claim 1, characterized in that, The housing includes a water outlet pipe, with the inlet of the water outlet pipe located at the front end of the housing and connected to the impeller cavity, and the outlet of the water outlet pipe located at the rear end of the housing.

5. The brushless DC water pump according to claim 4, characterized in that, The pump head has a slope at the position facing the inlet of the outlet pipe, and the slope guides the high-pressure water flow in the impeller cavity into the inlet of the outlet pipe.

6. The brushless DC water pump according to any one of claims 1-5, characterized in that, The pump head has a first groove, the water inlet is located at the bottom of the first groove, and the pump head is fixed to the front end of the housing with the first groove facing the housing. The impeller cavity is formed by the first groove.

7. The brushless DC water pump according to claim 6, characterized in that, The rotor cavity has a bearing seat at its bottom, and the front end of the outer shell has a second groove surrounding the opening of the rotor cavity; the rotor assembly includes a rear bearing, a front bearing, a front bearing plate, a rotating shaft, and a rotor body. The rear bearing is installed in the bearing seat, the front bearing is installed on the front bearing plate, the front bearing plate is installed in the second groove, and the rotor body is installed between the front bearing and the rear bearing via the rotating shaft, with the front part of the rotating shaft forming the output end of the rotor assembly.

8. The brushless DC water pump according to any one of claims 1-5, characterized in that, The brushless DC water pump includes a stator assembly and a control circuit board. The housing includes a stator cavity that is isolated from the rotor cavity. The opening of the stator cavity is located at the tail end of the housing. The stator assembly and the control circuit board are respectively installed in the stator cavity, and the stator assembly is located in the portion of the stator cavity surrounding the rotor cavity.

9. The brushless DC water pump according to claim 8, characterized in that, The outer wall of the first end of the housing has a plurality of axially arranged nut seats, and the plurality of nut seats are evenly distributed along the circumference of the housing; the pump head has a plurality of first fixing holes corresponding to the nut seats, and the pump head is fixed to the first end of the housing by a plurality of screws passing through the first fixing holes and threadedly connected to the nuts in the nut seats of the housing.

10. The brushless DC water pump according to claim 9, characterized in that, The first end of the housing is formed with a flange, and the flange has a plurality of second fixing holes; a plurality of nut seats are respectively connected to the side of the flange facing away from the pump head, each nut seat includes a hexagonal prism groove with an opening located at the end facing away from the pump head and communicating with the second fixing holes, and the cross-sectional dimensions of the hexagonal prism groove are adapted to the dimensions of the nut.

Images