Brushless external fuel pump

Abstract

The brushless external fuel pump comprises a pump head assembly, a motor assembly, a connecting disc assembly and a control assembly, the pump head assembly is arranged at the upper end of the motor assembly, the control assembly is arranged at the lower end of the motor assembly, and the connecting disc assembly is arranged between the pump head assembly and the motor assembly. The motor assembly comprises a motor shell, a motor stator assembly, an oil separation sleeve assembly and a motor rotor assembly which are sequentially arranged from outside to inside. The pump head assembly comprises a pump head installed on the motor shell, an oil inlet channel with one end communicating with the outside of the left side of the pump head and an oil outlet channel with one end communicating with the outside of the right side of the pump head are arranged in the pump head, and a cycloid gear assembly is arranged at the lower end of the pump head. The other end of the fuel inlet channel is communicated with the other end of the fuel outlet channel through the cycloid gear assembly, the requirements for high fuel pressure and large flow of a large heavy truck can be met, and the service life of the fuel pump is guaranteed.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of automobile fuel supply system, and particularly relates to a brushless external fuel pump. BACKGROUND

[0002] In the prior art, a fuel pump usually adopts a 12V power-driven brush DC motor, and the typical structure comprises a motor part and a pump body part, wherein the motor part comprises a stator (permanent magnet and carbon brush), a rotor (commutator and armature winding) and a power supply, the switching of the current direction is realized by the contact of the carbon brush and the commutator, the pump body part is assembled and cooperated by an impeller, an oil inlet end cover and an oil outlet end cover to form a pump chamber, and then the motor shaft drives the impeller to rotate to realize the fuel medium pressure output.

[0003] The above structure is usually placed in the oil tank and is suitable for small-power fuel pumps, that is, the power is within 150W, the pressure is 550KPa, and the flow is about 200L / h, which cannot meet the high fuel pressure and large flow requirements (the pressure is more than 600KPa, the flow is about 500L / h, and the motor power is about 300W) required by large heavy trucks. Moreover, the carbon brush and the commutator are used, and wear and noise will occur during work, thereby affecting the service life of the fuel pump, especially when used in special oil (such as methanol and ethanol), the wear of the carbon brush and the commutator will be aggravated, further affecting the service life of the fuel pump. SUMMARY

[0004] The present application proposes a brushless external fuel pump, which can not only meet the high fuel pressure and large flow requirements required by large heavy trucks, but also ensure the service life of the fuel pump.

[0005] To this end, the technical scheme adopted by the present application is as follows: a brushless external fuel pump, comprising a pump head assembly, a motor assembly, a connecting disc assembly and a control assembly, the pump head assembly is arranged at the rear end of the motor assembly, the control assembly is arranged at the lower end of the motor assembly, the connecting disc assembly is arranged between the pump head assembly and the motor assembly, and the motor assembly comprises, from the outside to the inside, a motor shell, a motor stator assembly, an oil separation sleeve assembly and a motor rotor assembly.

[0006] The pump head assembly comprises a pump head mounted on the motor shell, an oil inlet channel with one end communicated with the left side of the pump head and an oil outlet channel with one end communicated with the right side of the pump head are arranged in the pump head, a trochoid gear assembly is arranged at the lower end of the pump head, the other end of the oil inlet channel and the other end of the oil outlet channel are communicated through the trochoid gear assembly, the end of the oil inlet channel is provided with an oil inlet nozzle, and the end of the oil outlet channel is provided with an oil outlet nozzle.

[0007] As the preferred in the above scheme, the cycloid gear assembly comprises a cycloid gear arranged on the upper end of the motor rotor assembly, the cycloid gear is embedded in the gear fixing sleeve through the gear sleeve, the upper and lower ends of the gear fixing sleeve are correspondingly provided with a gear upper cover plate and a gear lower cover plate for sealing the cycloid gear, and the gear upper cover plate is provided with a communication hole at positions corresponding to the oil inlet channel and the oil outlet channel.

[0008] Further preferably, the motor rotor assembly comprises a motor shaft and a rotor assembly arranged on the motor shaft, the oil separation sleeve assembly comprises an oil separation sleeve and a lower bearing, the lower bearing is arranged on the lower end of the motor shaft, and the lower bearing is press-fitted in the lower end of the oil separation sleeve, the connecting disc assembly comprises a connecting disc and an upper bearing arranged on the upper end of the motor shaft, and the upper bearing is embedded in the lower end of the connecting disc, the upper end of the connecting disc is provided with a mounting end face between the pump head and the motor shell, and the upper end of the oil separation sleeve is arranged outside the lower end of the connecting disc.

[0009] Further preferably, the pump head is further provided with a drain hole in communication with the oil outlet channel, the drain hole is provided with a safety valve, and the pump head is provided with a drain nozzle outside the drain hole.

[0010] Further preferably, the control assembly comprises a controller arranged on the lower end of the motor shell, and an insulating plate is arranged between the controller and the motor shell, the motor shell is provided with a rear cover for accommodating the controller, the motor shell is provided with a wire passing hole for the lead wire of the motor stator assembly to pass through, and the rear cover is provided with a junction box for the lead wire and the power supply wire to access and connect with the controller.

[0011] Further preferably, the rear end of the motor shell is provided with a mounting groove for mounting the controller, the mounting groove is filled with a heat-conducting fixing glue, the rear cover is provided with a heat dissipation structure, and the motor shell and the rear cover are both made of aluminum alloy.

[0012] Further preferably, the motor stator assembly comprises a stator core, and the upper and lower ends of the stator core are both provided with a stator assembly with windings.

[0013] The beneficial effects of the present application are as follows:

[0014] 1) The cycloid gear assembly is used to replace the impeller assembly in the prior art, and the cycloid gear assembly has higher structural strength, so that the high fuel pressure and large flow required by large heavy trucks can be met.

[0015] 2) The control assembly replaces the carbon brush and commutator in the prior art, which not only ensures the rotation speed, torque and stability of the motor assembly, meets the on-demand fuel supply of the automobile fuel pump, but also does not cause friction, and the motor rotor assembly and the motor stator assembly in the motor assembly are isolated by the oil separation sleeve assembly and the connecting disc assembly, which can effectively prevent the motor stator assembly from being corroded in special oil, thereby ensuring the service life of the fuel pump. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 The figure is a schematic diagram of the present application (the arrows in the figure are the medium flow direction).

[0017] The figure is a schematic diagram of the present application (the arrows in the figure are the medium flow direction). DETAILED DESCRIPTION

[0018] The present application will be further described below by examples and in conjunction with the drawings:

[0019] As shown in the figure, a brushless external fuel pump mainly consists of a pump head assembly, a motor assembly, a connecting disc assembly and a control assembly. The pump head assembly is arranged at the upper end of the motor assembly and is used to communicate with the automobile inlet and outlet oil pipeline. The control assembly is arranged at the lower end of the motor assembly and is used to control the work of the motor assembly. The connecting disc assembly is arranged between the pump head assembly and the motor assembly, which not only realizes the isolation of the pump head assembly and the motor assembly, but also supports the upper end of the motor assembly. Figure 1 The motor assembly includes a motor shell 1, a motor stator assembly, an oil separation sleeve assembly and a motor rotor assembly arranged from outside to inside. The motor stator assembly includes a stator core 23, and the upper and lower ends of the stator core 23 are provided with a stator assembly 22 with windings.

[0020]

[0021] ​The motor rotor assembly comprises a motor shaft 10 and a rotor assembly 25 sleeved on the motor shaft 10. The oil separation sleeve assembly comprises an oil separation sleeve 11 and a lower bearing 12, the lower bearing 12 is sleeved on the lower end of the motor shaft 10, and the lower bearing 12 is press-fitted in the lower end of the oil separation sleeve 11. The connecting disc assembly comprises a connecting disc 13 and an upper bearing 14 sleeved on the upper end of the motor shaft, and the upper bearing 14 is embedded in the lower end of the connecting disc 13, and the upper and lower ends of the motor rotor assembly are supported by the upper bearing 14 and the lower bearing 12. The upper end of the connecting disc 13 is provided with a mounting end surface between the pump head 2 and the motor shell 1, and the upper end of the oil separation sleeve 11 is sleeved on the lower end of the connecting disc 13. Through the cooperation of the oil separation sleeve and the connecting disc, the dry and wet separation and isolation of the motor rotor assembly and the motor stator assembly can be effectively realized, so as to prevent the medium from corroding the motor stator assembly, and thus the service life of the fuel pump is ensured.

[0022] The pump head assembly comprises a pump head 2 mounted on the motor shell 1, an oil inlet channel with one end communicated with the left side of the pump head 2 and an oil outlet channel with one end communicated with the right side of the pump head 2 are arranged in the pump head 2, a cycloidal gear assembly is arranged at the lower end of the pump head 2, and the other end of the oil inlet channel and the other end of the oil outlet channel are communicated through the cycloidal gear assembly, an oil inlet nozzle 3 connected with the output pipeline of the oil tank is arranged at the end of the oil inlet channel, and an oil outlet nozzle 4 connected with the oil inlet pipeline of the power assembly is arranged at the end of the oil outlet channel.

[0023] The cycloidal gear assembly comprises a cycloidal gear 5 sleeved on the upper end of the motor rotor assembly, the cycloidal gear 5 is embedded in a gear fixed sleeve 7 through a gear sleeve 6, a gear upper cover plate 8 and a gear lower cover plate 9 for sealing the cycloidal gear 5 are arranged at the upper and lower ends of the gear fixed sleeve 7, and communication holes are arranged on the gear upper cover plate 8 at positions corresponding to the oil inlet channel and the oil outlet channel.

[0024] In order to prevent the pipeline from bursting when the oil outlet nozzle or the oil pipeline is blocked, a drain hole communicated with the oil outlet channel is arranged in the pump head 2, a safety valve 15 is arranged on the drain hole, and a drain nozzle 16 connected with the oil return pipeline of the power assembly is arranged on the pump head 2 corresponding to the drain hole, when the pressure of the medium in the oil outlet channel is greater than a set value, the safety valve is opened, so that the medium returns to the oil return pipeline through the drain nozzle from the drain hole.

[0025] The control assembly comprises a controller 17 arranged at the lower end of the motor shell 1, an insulating plate 18 is arranged between the controller 17 and the motor shell 1, a rear cover 19 for containing the controller 17 is arranged on the motor shell 1, a wire passing hole for the lead wire of the motor stator assembly to pass through is arranged on the motor shell 1, and a junction box 20 for the lead wire and the power supply wire to access the controller is arranged on the rear cover 19. The controller adopts the existing technology with the functions of information receiving, information processing and information sending.

[0026] In order to realize the heat dissipation of the controller, the mounting groove for mounting the controller is arranged at the rear end of the motor shell 1, the heat-conducting fixing glue 21 is filled in the mounting groove, the heat-conducting fixing glue can not only transfer heat, but also fix the wires or power lines in the mounting groove, and the heat dissipation structure is arranged on the rear cover 19, and the motor shell 1 and the rear cover 19 are made of aluminum alloy. The heat of the controller is transferred to the motor shell or the rear cover through the heat-conducting fixing glue, and since the fuel pump is installed outside the oil tank, the motor shell and the rear cover can be cooled under the action of natural wind, so as to ensure the heat dissipation of the controller.

[0027] When the whole fuel pump is assembled, it is first assembled into several large parts, and then the whole assembly is realized, specifically:

[0028] The safety valve, the oil drain nozzle, the oil inlet nozzle and the oil outlet nozzle are mounted on the pump head to form a non-powered pump head assembly, the cycloid gear assembly is assembled, the motor stator assembly is mounted in the motor shell to form a motor shell assembly, the upper bearing is press-fitted on the connecting disc to form a connecting disc assembly, and the lower bearing is press-fitted on the oil separation sleeve to form an oil separation sleeve assembly;

[0029] Then, the oil separation sleeve assembly is mounted on the motor shell assembly, the motor rotor assembly is put into the oil separation sleeve assembly, and the lower end of the motor shaft is supported by the lower bearing, the connecting disc is sleeved on the upper end of the motor shaft, and the upper end of the motor shaft is supported by the upper bearing, the cycloid gear assembly is mounted on the upper end of the motor shaft, and when the motor shaft rotates, the inner rotor in the cycloid gear rotates, then the non-powered pump head assembly, the connecting disc assembly and the motor shell assembly are fixed, so as to complete the installation of the upper end of the motor.

[0030] The controller is fixed on the lower end of the motor shell, and the insulating plate is arranged between the controller and the motor shell, then the stator wiring is fixed with the controller, the heat-conducting fixing glue is filled in the mounting groove, then the power line and the wire of the controller are fixed with the junction box, the junction box is fixed with the rear cover, the rear cover is fixed with the motor shell, and the installation of the whole fuel pump is completed.

Claims

1. A brushless external fuel pump, characterized in that: It includes a pump head assembly, a motor assembly, a connecting plate assembly and a control assembly. The pump head assembly is located at the upper end of the motor assembly, the control assembly is located at the lower end of the motor assembly, and the connecting plate assembly is located between the pump head assembly and the motor assembly. The motor assembly includes a motor housing (1), a motor stator assembly, an oil separator assembly and a motor rotor assembly arranged sequentially from the outside to the inside. The pump head assembly includes a pump head (2) mounted on a motor housing (1). The pump head (2) has an oil inlet channel with one end connected to the left side of the pump head (2) and an oil outlet channel with one end connected to the right side of the pump head. The lower end of the pump head (2) is provided with a cycloidal gear assembly. The other end of the oil inlet channel and the other end of the oil outlet channel are connected through the cycloidal gear assembly. The end of the oil inlet channel is equipped with an oil inlet nozzle (3), and the end of the oil outlet channel is equipped with an oil outlet nozzle (4).

2. The brushless external fuel pump according to claim 1, characterized in that: The cycloidal gear assembly includes a cycloidal gear (5) sleeved on the upper end of the motor rotor assembly. The cycloidal gear (5) is embedded in the gear fixing sleeve (7) through a gear sleeve (6). The upper and lower ends of the gear fixing sleeve (7) are respectively provided with a gear upper cover plate (8) and a gear lower cover plate (9) for sealing the cycloidal gear (5). The gear upper cover plate (8) is provided with a connecting hole at the position corresponding to the oil inlet channel and the oil outlet channel.

3. The brushless external fuel pump according to claim 1, characterized in that: The motor rotor assembly includes a motor shaft (10) and a rotor assembly (25) fitted over the motor shaft (10). The oil separator assembly includes an oil separator (11) and a lower bearing (12). The lower bearing (12) is fitted over the lower end of the motor shaft (10) and is press-fitted into the lower end of the oil separator (11). The connecting disc assembly includes a connecting disc (13) and an upper bearing (14) fitted over the upper end of the motor shaft. The upper bearing (14) is embedded in the lower end of the connecting disc (13). The upper end of the connecting disc (13) is provided with an mounting end face located between the pump head (2) and the motor housing (1). The upper end of the oil separator (11) is fitted over the lower end of the connecting disc (13).

4. The brushless external fuel pump according to claim 1, characterized in that: The pump head (2) is also provided with an oil drain hole that communicates with the oil outlet channel. A safety valve (15) is provided on the oil drain hole, and an oil drain nozzle (16) is provided on the pump head (2) corresponding to the outside of the oil drain hole.

5. The brushless external fuel pump according to claim 1, characterized in that: The control assembly includes a controller (17) disposed at the lower end of the motor housing (1), and an insulating plate (18) is disposed between the controller (17) and the motor housing (1). The motor housing (1) is provided with a rear cover (19) for including the controller (17). The motor housing (1) is provided with a wire hole through which the stator assembly wires of the power supply are passed. The rear cover (19) is provided with a junction box (20) for wires and power lines to be connected to the controller.

6. The brushless external fuel pump according to claim 5, characterized in that: The rear end of the motor housing (1) is provided with a mounting groove for mounting the controller. The mounting groove is filled with thermally conductive fixing adhesive (21). The rear cover (19) is provided with a heat dissipation structure. Both the motor housing (1) and the rear cover (19) are made of aluminum alloy.

7. The brushless external fuel pump according to claim 1, characterized in that: The motor stator assembly includes a stator core (23), and stator assemblies (22) with windings are provided at both the upper and lower ends of the stator core (23).

Images