Combined fuel pump

Abstract

The present invention relates to the technical field of fuel pumps, and in particular to a combined fuel pump, which comprises a pump casing, a pump cover being arranged on the pump casing, and an oil extraction chamber being formed between the pump cover and the pump casing; a filter screen, a first oil inlet plate, and a second oil inlet plate are sequentially inserted in the pump cover in a direction away from the oil inlet, the first oil inlet plate and the second oil inlet plate are coaxially arranged, and both the first oil inlet plate and the second oil inlet plate can elastically slide along the direction of their own axes; a first impeller is inserted in the first oil inlet plate, the first impeller can rotate around its own axis, and has a plurality of first blades; an electric motor is inserted in the oil extraction chamber, and the electric motor is used to provide a driving force for the first impeller to rotate around its own axis; a second impeller is inserted in the second oil inlet plate, the second impeller can rotate around its own axis, and has a plurality of second blades, and the second blades and the first blades partially overlap along the axis direction of the second impeller, so that when the filter screen is blocked, the first impeller moves downward under the action of the pressure difference to increase the suction force.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel pumps, in particular to a combined fuel pump. Background Art

[0002] The fuel pump is a key component in the fuel system. Its main function is to extract fuel from the fuel tank and deliver it to the engine's fuel injection system or carburetor at a certain pressure. According to different designs and usage scenarios, fuel pumps can be divided into two types: mechanical fuel pumps and electric fuel pumps. Among them, electric fuel pumps are widely used due to their advantages such as stable oil output and high oil output efficiency.

[0003] In the related technology, for example, Chinese patent CN205047334U discloses a high-durability electric fuel pump. When the high-durability electric fuel pump is in operation, the fuel is introduced into the pump from the oil inlet. The filter screen will filter the fuel before it enters the pump. Then the motor drives the impeller to rotate, and the blades on the impeller introduce the fuel into the one-way valve and discharge it after applying a certain pressure.

[0004] Although the above-mentioned high-durability electric fuel pump can pump fuel, it is found in actual use that when the fuel pump is pumping fuel, impurities will adhere to the surface of the filter, and then gradually clog the filter, resulting in reduced fuel absorption efficiency. Summary of the invention

[0005] Based on this, it is necessary to provide a combined fuel pump to address the problem of low fuel suction efficiency in the current fuel pump during the fuel suction process.

[0006] The above purpose is achieved through the following technical solutions:

[0007] A combined fuel pump, the combined fuel pump comprising a pump housing, a pump cover and an oil outlet are arranged on the pump housing, an oil inlet is arranged on the pump cover, an oil pumping chamber is formed between the pump cover and the pump housing, and the oil pumping chamber is communicated with the oil outlet and the oil inlet at the same time; a filter screen, a first oil inlet pan and a second oil inlet pan are sequentially inserted in the pump cover in a direction away from the oil inlet, the first oil inlet pan and the second oil inlet pan are coaxially arranged and each of them is provided with a plurality of first through holes, the first through holes communicate the oil inlet and the oil pumping chamber, and the first oil inlet pan and the second oil inlet pan can elastically slides along its own axial direction; a first impeller is installed in the first oil inlet tray, the first impeller can rotate around its own axis, the first impeller has a plurality of first blades, and the plurality of first blades are arranged along the circumferential direction; an electric motor is installed in the oil pumping chamber, the motor is configured to provide a driving force for the first impeller to rotate around its own axis; a second impeller is installed in the second oil inlet tray, the second impeller can rotate around its own axis, the second impeller has a plurality of second blades, the second blades and the first blades are arranged correspondingly, and partially overlap along the axial direction of the second impeller.

[0008] Furthermore, a one-way valve is provided at the oil outlet, and the opening direction of the one-way valve is configured to be from the oil pumping chamber to the oil outlet.

[0009] Furthermore, the combined fuel pump also includes a sensing element, which is configured to sense the degree of blockage of the filter, and when the degree of blockage of the filter is greater than or equal to a preset degree, the sensing element is configured to send a signal to the motor to reverse the motor to drive the fuel in the oil extraction chamber to recoil the filter through the first impeller and the second impeller.

[0010] Furthermore, the combined fuel pump further comprises a first elastic member, and the first elastic member is configured to drive the first oil inlet plate to slide elastically along its own axial direction.

[0011] Furthermore, a first blocking portion is provided on the first blade, and a second blocking portion is provided on the second blade, and the first blocking portion and the second blocking portion are matched with each other to enable the first impeller to synchronously drive the second impeller to move, thereby compressing the first elastic member; the sensing member is configured as a pressure sensor, and the pressure sensor is configured to sense the pressure change of the first elastic member to indirectly determine the degree of blockage of the filter.

[0012] Furthermore, the sensing element is configured as a fluid pressure sensor, and the fluid pressure sensor is configured to sense the pressure inside the pump cover to indirectly determine the degree of blockage of the filter.

[0013] Furthermore, the combined fuel pump further comprises a second elastic member, and the second elastic member is configured to drive the second oil inlet plate to slide elastically along its own axial direction.

[0014] Furthermore, the second elastic member is a second compression spring, and is connected between the second oil inlet pan and the pump cover. Under the action of the second compression spring, the second oil inlet pan has a tendency to move in a direction away from the oil inlet.

[0015] Furthermore, a plurality of first rollers are provided on the first impeller, the plurality of first rollers are arranged in a circumferential direction, the axes of the first rollers and the axis of the first impeller are vertically arranged, and the first rollers and the first oil inlet pan form a rolling fit.

[0016] Furthermore, the first impeller and / or the second impeller are made of ceramic material.

[0017] The beneficial effects of the present invention are:

[0018] When the filter of the combined fuel pump provided by the present invention is clogged, a pressure difference will appear on both sides of the first impeller, and as the degree of clogging of the filter becomes greater and greater, the pressure difference on both sides of the first impeller will become greater and greater, and then under the action of the pressure difference, the first impeller will move toward the direction close to the oil inlet. Since the second blade and the first blade are arranged correspondingly and partially overlap along the axial direction of the second impeller, as the first impeller moves, the first blade and the second blade will move away from each other, thereby increasing the effective action area of ​​the first blade, thereby increasing the suction force and improving the suction efficiency of the fuel.

[0019] Furthermore, by setting up a sensing element, the sensing element is configured to sense the degree of blockage of the filter, so that when the degree of blockage of the filter is greater than or equal to a preset degree, the sensing element is configured to send a signal to the motor to reverse the motor, so as to drive the fuel in the oil extraction chamber to backflush the filter through the first impeller and the second impeller, thereby cleaning the filter. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic diagram of the three-dimensional structure of a combined fuel pump provided in an embodiment of the present invention;

[0021] Figure 2 A schematic diagram of the exploded parts of a combined fuel pump provided by an embodiment of the present invention;

[0022] Figure 3 for Figure 2 A schematic diagram of the partially enlarged structure at center A;

[0023] Figure 4 for Figure 2 A schematic diagram of the partially enlarged structure at B in the middle;

[0024] Figure 5 A schematic cross-sectional view of a combined fuel pump provided in an embodiment of the present invention;

[0025] Figure 6 The working state of the first blade and the second blade of the combined fuel pump provided by the embodiment of the present invention when they cooperate Figure 1 ;

[0026] Figure 7 The working state of the first blade and the second blade of the combined fuel pump provided by the embodiment of the present invention when they cooperate Figure 2 .

[0027] in:

[0028] 1. Pump casing; 101. Oil outlet; 102. Oil outlet pipe; 2. Pump cover; 201. Oil inlet; 202. Second through hole; 203. Partition; 204. First telescopic ring; 3. Oil extraction chamber; 4. First oil inlet plate; 401. Second telescopic ring; 5. Second oil inlet plate; 6. First through hole; 7. First impeller; 701. First blade; 8. Second impeller; 801. Second blade; 9. Motor; 901. Rotor; 902. Stator; 903. Commutator; 904. Brush; 905. Connector; 10. One-way valve; 1001. Ball plug; 1002. Third compression spring; 11. First blocking portion; 12. Second blocking portion; 13. First compression spring; 14. Second compression spring; 15. First roller; 16. Second roller. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below through embodiments and in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0030] The serial numbers assigned to the components herein, such as "first", "second", etc., are only used to distinguish the objects described and do not have any order or technical meaning. The "connection" and "coupling" mentioned herein, unless otherwise specified, include direct and indirect connections (couplings). In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention.

[0031] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0032] like Figures 1 to 7 As shown, the combined fuel pump provided by the embodiment of the present invention is used to suck the fuel in the fuel tank to a designated area, such as an engine, and is configured to include a pump housing 1, a pump cover 2 and an oil outlet 101 are provided on the pump housing 1, an oil inlet 201 is provided on the pump cover 2, an oil pumping chamber 3 is formed between the pump cover 2 and the pump housing 1, and the oil pumping chamber 3 is connected to the oil outlet 101 and the oil inlet 201 at the same time; a filter (not shown), a first oil inlet plate 4, and a second oil inlet plate 5 are sequentially inserted in the pump cover 2 in a direction away from the oil inlet 201, the first oil inlet plate 4 and the second oil inlet plate 5 are coaxially arranged, and a first through hole 6 is provided on each of them, and the first through hole 6 connects the oil inlet 201 and the oil pumping chamber 3 , the first oil inlet plate 4 and the second oil inlet plate 5 can both slide elastically along their own axial lines; the first oil inlet plate 4 is installed with a first impeller 7, which can rotate around its own axis, and the first impeller 7 has a plurality of first blades 701, and the plurality of first blades 701 are arranged along the circumferential direction; the oil pumping chamber 3 is installed with a motor 9, and the motor 9 is configured to provide a driving force for the first impeller 7 to rotate around its own axis; the second oil inlet plate 5 is installed with a second impeller 8, which can rotate around its own axis, and the second impeller 8 has a plurality of second blades 801, and the second blades 801 and the first blades 701 are arranged correspondingly, and partially overlap along the axial direction of the second impeller 8.

[0033] Specifically in this embodiment, in order to ensure that the fuel can always maintain a smooth state when flowing in the pump housing 1 and avoid turbulence and energy loss caused by corners, as shown in FIG. Figure 1 As shown, the pump housing 1 is configured as a cylindrical structure; specifically, the cylindrical structure makes the inner wall of the pump housing 1 smooth and continuous without sharp corners. Since there are no corners, there will be no dead points, thereby avoiding problems such as impurity precipitation and blockage.

[0034] To facilitate the formation of the oil outlet 101, as Figure 1 As shown, an oil outlet pipe 102 is provided at the top of the pump housing 1 , and an oil outlet port 101 is formed at a pipe opening of the oil outlet pipe 102 away from one end of the pump housing 1 .

[0035] In order to make the pump housing 1 and the pump cover 2 fit together, Figure 1and Figure 2 As shown, the bottom of the pump casing 1 is open, the pump cover 2 is a cylindrical structure, and is coaxially inserted into the bottom of the pump casing 1; to facilitate the formation of the oil extraction chamber 3, the pump cover 2 is sealed and connected to the pump casing 1 to block the bottom opening of the pump casing 1.

[0036] It can be understood that the pump casing 1 and the pump cover 2 can be connected by bolts; specifically, screw holes can be processed on the pump cover 2, and mounting holes can be processed at corresponding positions of the pump casing 1, and bolts can be passed through the mounting holes on the pump casing 1 and screwed into the screw holes on the pump cover 2 to fasten the two together; and to ensure the sealing of the connection, a sealing gasket, such as a rubber gasket or a paper gasket, can be placed between the pump casing 1 and the pump cover 2.

[0037] In order to reduce the impurities from entering the subsequent first impeller 7 and second impeller 8, Figure 2 As shown, the oil inlet 201 is opened at the bottom of the pump cover 2; specifically, when the fuel enters the pump cover 2 through the oil inlet 201, larger impurity particles are more likely to settle to the bottom of the pump cover 2 due to gravity, rather than directly entering the subsequent first impeller 7 and second impeller 8, which helps to preliminarily filter impurities in the fuel and reduce the burden on the filter.

[0038] In order to make the oil pumping chamber 3 communicate with the oil inlet 201, Figure 2 As shown, a plurality of second through holes 202 are opened on the top of the pump cover 2 , and the second through holes 202 communicate with the oil pumping chamber 3 and the oil inlet 201 .

[0039] In order to facilitate the installation of the first oil inlet pan 4 and enable the first oil inlet pan 4 to slide only along its own axis, as shown in FIG. Figure 2 As shown, a partition 203 is arranged in the pump cover 2, and the plate surface of the partition 203 is arranged perpendicularly to the axis of the pump cover 2, and a plurality of first telescopic rings 204 are arranged vertically through the top plate surface of the partition 203, and a plurality of second telescopic rings 401 are arranged vertically through the bottom plate surface of the first oil inlet pan 4, and the first through hole 6 and the second telescopic ring 401 on the first oil inlet pan 4 are arranged correspondingly. The second telescopic ring 401 is correspondingly sleeved on the first telescopic ring 204 during installation, and can slide relative to the first telescopic ring 204 along its own axial direction to form a sliding telescopic fit with the first telescopic ring 204, thereby facilitating the first oil inlet pan 4 to slide only along its own axial direction.

[0040] The filter is located at the lower side of the partition 203 when installed, so as to filter the fuel before the fuel enters the first impeller 7 and the second impeller 8.

[0041] like Figure 2 and Figure 4As shown, the first impeller 7 is configured as a concentric ring structure, and the first blades 701 are tiltedly arranged between the two concentric rings of the first impeller 7, and an inclined first oil pumping channel is formed between adjacent first blades 701, so that during the rotation of the first impeller 7, when a first oil pumping channel rotates to approach the first through hole 6 on the first oil inlet plate 4, its volume gradually increases, the internal pressure decreases, and a negative pressure is formed. Under the action of the external atmospheric pressure or the pressure in the fuel tank, the fuel is pressed into the first oil pumping channel. As the first impeller 7 continues to rotate, the volume of the first oil pumping channel gradually decreases, the fuel is squeezed, the pressure increases, and then it is continuously transported; and a plurality of first blades 701 are configured to be evenly arranged along the circumferential direction, so that the same first oil pumping channel can be formed between adjacent first blades 701, so that during the rotation of the first impeller 7, the ability of each first oil pumping channel to suck and transport fuel is the same, ensuring that the fuel can be evenly sucked in and discharged, avoiding unstable fuel supply caused by differences between the first oil pumping channels, thereby providing a stable fuel flow for the engine and other equipment to ensure its stable operation.

[0042] like Figure 2 and Figure 3 As shown, the second impeller 8 is configured as a concentric ring structure, and the second blade 801 is tilted between the two concentric rings of the second impeller 8. The multiple second blades 801 are evenly arranged along the circumferential direction, so that the same second oil pumping channel can be formed between adjacent second blades 801, and the second oil pumping channel and the first oil pumping channel are correspondingly connected to each other so as to lengthen the oil pumping path of the first oil pumping channel. At the same time, the existence of the second blade 801 extends the effective action area of ​​the first blade 701. The larger effective action area of ​​the first blade 701 means that when the first impeller 7 rotates, there is more area to exert force on the fuel. The force exerted by the first blade 701 on the fuel is increased, so that the fuel can obtain greater kinetic energy, thereby improving the suction force on the fuel to ensure the oil suction efficiency.

[0043] To improve the oil extraction efficiency, the multiple first through holes 6 on the first oil inlet plate 4 are evenly arranged along the circumferential direction and located between the two concentric rings of the first impeller 7, so that the first oil extraction channel can be directly connected to the first through holes 6 on the first oil inlet plate 4 to simplify the oil delivery path.

[0044] Similarly, the multiple first through holes 6 on the second oil inlet plate 5 are evenly arranged along the circumferential direction and located between the two concentric rings of the second impeller 8, so that the second oil suction channel can be directly connected to the first through holes 6 on the second oil inlet plate 5 to simplify the oil delivery path.

[0045] The motor 9 is configured to be composed of a rotor 901, a stator 902, a commutator 903, a brush 904 and a connector 905, wherein the top end of the rotor 901 is rotatably arranged on the inner top wall surface of the pump housing 1, and the bottom end is suspended. The rotor 901 is composed of a plurality of coils and an iron core. These coils are distributed on the iron core according to a certain rule, and when current flows into a certain coil, the coil becomes a current-carrying conductor; the stator 902 is configured to be an arc-shaped plate-like structure, and there are two of them. The two stators 902 are symmetrically arranged on the inner circumferential wall of the pump housing 1, and the stators 902 are configured to generate a magnetic field. The two stators 902 can work together to generate a stable magnetic field with a specific direction, and the magnetic field interacts with the energized coil in the rotor 901, thereby generating an electromagnetic force that drives the rotor 901 to rotate; the commutator 903 is composed of a plurality of commutator segments, and together with the rotor 9 01 is connected and rotates with the rotor 901. When the rotor 901 rotates a certain angle, the commutator 903 will change the flow direction of the current in the rotor 901, so that when each coil is in a different position, the direction of the Ampere force it receives can always maintain the rotor 901 rotating in the same direction. This process ensures that the motor 9 outputs stable rotational power and avoids the unstable rotation or stagnation of the rotor 901 due to the uncertainty of the direction of the Ampere force; the brush 904 is arranged on the inner top wall surface of the pump housing 1, and its position is closely matched with the commutator 903 at the top of the rotor 901. The main function of the brush 904 is to introduce the current of the external power supply into the rotating rotor 901. When the motor 9 is running, the brush 904 and the commutator 903 maintain good sliding contact to ensure that the current can be stably and reliably transmitted to each coil of the rotor 901.

[0046] In order to enable the motor 9 to drive the first impeller 7 to rotate through the connector 905, as shown in FIG. Figure 2 and Figure 5 As shown, a first center hole is opened in the middle of the first impeller 7, and a slot is opened on the inner circumferential wall of the first center hole; the connector 905 is set as an inverted T-shaped columnar structure, and a protrusion is set on the circumferential side wall of the large column of the connector 905, and the protrusion is inserted in the slot during installation to form a snap-fit ​​fit, so that the connector 905 can both synchronously follow the first impeller 7 to move axially and drive the first impeller 7 to rotate; a columnar sink groove is coaxially opened at the bottom end of the iron core of the rotor 901, and a slide groove is opened on the inner circumferential wall of the columnar sink groove, and the slide groove extends along the axial direction of the rotor 901, and a slide bar is set on the circumferential side wall of the small column of the connector 905, and the slide bar extends along the axial direction of the connector 905. The slide bar is slidably inserted in the slide groove during installation, so that the connector 905 can both move axially relative to the rotor 901 and synchronously follow the rotation of the rotor 901.

[0047] To avoid interference, a second center hole is opened in the middle of the top of the second oil inlet plate 5, the second impeller 8 and the pump cover 2. When installing, the bottom end of the iron core of the rotor 901 passes through all the second center holes at the same time to be sleeved on the connector 905.

[0048] During use, the brush 904 is energized through an external power supply, and the brush 904 introduces the current of the external power supply into the rotor 901. According to the Ampere force law, the energized coil will be acted upon by a force in the magnetic field generated by the stator 902; the torque formed by the Ampere force on each coil drives the rotor 901 to overcome the resistance and start to rotate; when the rotor 901 rotates through a certain angle, the commutator 903 changes the flow direction of the current in the rotor 901, so that when each coil is in a different position, the direction of the Ampere force on it can always maintain the rotor 901 rotating in the same direction, thereby driving the rotor 901 to rotate continuously.

[0049] During the rotation of the rotor 901, the rotor 901 drives the connector 905 to rotate, and the connector 905 drives the first impeller 7 to rotate through the snap fit between the protrusion and the slot. Figure 6 As shown in the figure, when the first blade 701 abuts against the second blade 801, the second impeller 8 rotates synchronously with the push of the first blade 701; the fuel is sucked by the first impeller 7 and the second impeller 8 together. Figure 5 It moves in the direction of the arrow shown, and first enters the pump cover 2 from the oil tank through the oil inlet 201, then passes through the filter to filter out impurities, and then passes through the first telescopic ring 204, the second telescopic ring 401, the first through hole 6 on the first oil inlet plate 4, the first oil pumping channel, the second oil pumping channel, the first through hole 6 on the second oil inlet plate 5 in sequence, enters the oil pumping chamber 3, then gradually fills the oil pumping chamber 3, and finally is discharged from the oil outlet 101 to a designated area, such as an engine.

[0050] As the filter screen is continuously filtered, impurities on the filter screen will accumulate more and more, resulting in blockage. At this time, under the joint suction of the first impeller 7 and the second impeller 8, since the first impeller 7 is closer to the oil inlet 201 than the second impeller 8, a pressure difference first appears on both sides of the first impeller 7, and as the blockage degree of the filter screen becomes greater and greater, the pressure difference on both sides of the first impeller 7 will become greater and greater, and then under the action of the pressure difference, the first impeller 7 will move toward the oil inlet 201. Since the second blade 801 and the first blade 701 are correspondingly arranged and partially overlap along the axial direction of the second impeller 8, as the first impeller 7 moves, the first blade 701 and the second blade 801 will move away from each other, thereby increasing the effective action area of ​​the first blade 701, thereby increasing the suction force and improving the suction efficiency of the fuel.

[0051] In some embodiments, in order to prevent fuel backflow and maintain fuel injection pressure, a one-way valve 10 is provided at the fuel outlet 101 , and the opening direction of the one-way valve 10 is configured from the fuel extraction chamber 3 to the fuel outlet 101 .

[0052] Specifically in this embodiment, the one-way valve 10 can be configured to be composed of a blocking ball 1001 and a third compression spring 1002; in order to facilitate the blocking of the oil outlet 101 by the blocking ball 1001, as shown in FIG. Figure 2 As shown, a section of the oil outlet pipe 102 close to the pump housing 1 is set as a necking structure, and the necking of the necking structure faces the pump housing 1, the plugging ball 1001 and the third compression spring 1002 are both inserted in the necking structure, and the third compression spring 1002 is connected between the plugging ball 1001 and the oil outlet pipe 102. Under the push of the third compression spring 1002, the plugging ball 1001 is sealed in the necking structure.

[0053] During use, the setting of the one-way valve 10, on the one hand, prevents the fuel from flowing back into the oil extraction chamber 3 when the fuel pump stops working or the system pressure fluctuates, thereby ensuring that the fuel can be continuously and stably supplied to the engine and other equipment to maintain its normal operation; on the other hand, under the push of the third compression spring 1002, the ball blocking ball 1001 can only be pushed open when the oil pressure inside the oil extraction chamber 3 reaches a certain pressure value, so that the oil outlet 101 and the subsequent pipeline maintain a certain pressure, ensuring that the oil outlet 101 can accurately spray fuel according to the set injection amount and injection time under different working conditions, thereby improving the fuel atomization effect.

[0054] In a further embodiment, although the cooperation mechanism between the first impeller 7 and the second impeller 8 can continuously increase the suction force on the fuel to a certain extent to cope with the complex working condition where the filter blockage degree is getting worse and worse, when the filter blockage is extremely serious, even if the cooperation between the first impeller 7 and the second impeller 8 continues to play a role, it is still difficult to avoid some negative problems: as the filter is increasingly blocked, the resistance of the fuel entering the pump housing 1 increases exponentially. In this case, even if the first impeller 7 and the second impeller 8 continuously adjust the effective action area of ​​the first blade 701 through relative movement with each other, in an attempt to enhance the suction force on the fuel, Suction effect, but due to the excessive oil suction resistance, idling may still occur, and the idling of the fuel pump will affect the oil delivery efficiency on the one hand, and will cause additional damage to the first impeller 7, the second impeller 8 and the motor 9 on the other hand, affecting their service life. To solve this problem, the combined fuel pump also includes a sensor, which is configured to sense the degree of blockage of the filter, and when the degree of blockage of the filter is greater than or equal to a preset degree, the sensor is configured to send a signal to the motor 9, so that the motor 9 reverses, so as to drive the fuel in the oil extraction chamber 3 to recoil the filter through the first impeller 7 and the second impeller 8.

[0055] Specifically in this embodiment, when the motor 9 is reversed, the rotor 901 drives the connector 905 to rotate, and the connector 905 drives the first impeller 7 to rotate in the opposite direction through the snap fit between the protrusion and the slot. As the first impeller 7 rotates, Figure 7 As shown, when the first blade 701 abuts against the second blade 801, under the push of the first blade 701, the second impeller 8 synchronously follows the reverse rotation; under the joint suction of the first impeller 7 and the second impeller 8, the fuel in the oil pumping chamber 3 passes through the first through hole 6 on the second oil inlet plate 5, the second oil pumping channel, the first oil pumping channel, the first through hole 6 on the first oil inlet plate 4, the second telescopic ring 401, and the first telescopic ring 204 in sequence, and enters between the partition 203 and the pump cover 2, and recoils the impurities adhered to the filter screen, so that some impurities can fall to the bottom of the pump cover 2, and some impurities can pass through the oil inlet 201 back into the oil tank, thereby cleaning the filter screen.

[0056] In a further embodiment, the combined fuel pump is configured to further include a first elastic member, and the first elastic member is configured to be able to drive the first oil inlet plate 4 to slide elastically along its own axial direction.

[0057] Specifically in this embodiment, the first elastic member is configured as a first compression spring 13, such as Figure 5 As shown, the first compression spring 13 is vertically arranged during installation, and the top end is fixedly connected to the bottom of the first oil inlet pan 4, and the bottom end is fixedly connected to the top of the partition 203. Under the action of the first compression spring 13, the first oil inlet pan 4 has a tendency to move away from the partition 203, thereby facilitating the resetting of the first oil inlet pan 4 and the first impeller 7.

[0058] In a further embodiment, a first blocking portion 11 is provided on the first blade 701, and a second blocking portion 12 is provided on the second blade 801, and the first blocking portion 11 and the second blocking portion 12 are matched with each other to enable the first impeller 7 to synchronously drive the second impeller 8 to move to compress the first elastic member; the sensing member can be set as a pressure sensor, and the pressure sensor is configured to sense the pressure change of the first elastic member to indirectly determine the degree of blockage of the filter.

[0059] Specifically in this embodiment, Figure 4 As shown, the first blocking portion 11 is configured as a strip structure and extends in a direction perpendicular to the axis of the first impeller 7 and is disposed on the oblique side wall of the first blade 701. The first blocking portion 11 is disposed close to the top of the first blade 701; Figure 3 As shown, the second blocking portion 12 is configured as a strip structure and extends in a direction perpendicular to the axis of the second impeller 8 and is disposed on the oblique side wall of the second blade 801. The second blocking portion 12 is disposed close to the bottom of the second blade 801, and the second blocking portion 12 and the first blocking portion 11 are located on the same side.

[0060] The pressure sensor is disposed on the top of the partition 203 and is connected to the first compression spring 13 so as to sense the change of the elastic force of the first compression spring 13 .

[0061] During use, as the filter screen continuously filters, impurities on the filter screen will accumulate more and more, resulting in blockage. At this time, under the joint suction of the first impeller 7 and the second impeller 8, since the first impeller 7 is closer to the oil inlet 201 than the second impeller 8, a pressure difference first appears on both sides of the first impeller 7, and as the blockage of the filter screen becomes greater and greater, the pressure difference on both sides of the first impeller 7 will become greater and greater, and then under the action of the pressure difference, the first impeller 7 will move toward the direction close to the oil inlet 201. Since the second blade 801 and the first blade 701 are correspondingly arranged and partially overlap along the axial direction of the second impeller 8, as the first impeller 7 moves, the first blade 701 and the second blade 801 will move away from each other; Figure 6 As shown, until the first blocking portion 11 presses on the second blocking portion 12, and then the first impeller 7 synchronously drives the second impeller 8 to move toward the direction close to the oil inlet 201, the second impeller 8 compresses the first compression spring 13 through the second oil inlet plate 5, so that the elastic force of the first compression spring 13 increases. At this time, the pressure value sensed by the pressure sensor increases, indicating that the blockage degree of the filter reaches a preset degree. At this time, the pressure sensor sends a signal to the motor 9, causing the motor 9 to reverse, so as to drive the fuel in the oil extraction chamber 3 to recoil the filter through the first impeller 7 and the second impeller 8.

[0062] In other embodiments, the sensing element may also be configured as a fluid pressure sensor, and the fluid pressure sensor is configured to sense the pressure inside the pump cover 2 to indirectly determine the degree of clogging of the filter.

[0063] Specifically in this embodiment, the fluid pressure sensor can be inserted into the pump cover 2.

[0064] During use, the smaller the pressure inside the pump cover 2 sensed by the pressure sensor is, the greater the degree of blockage of the filter. When the pressure inside the pump cover 2 sensed by the pressure sensor is lower than the preset pressure, it means that the degree of blockage of the filter has reached the preset degree. At this time, the pressure sensor sends a signal to the motor 9, causing the motor 9 to reverse, so as to drive the fuel in the oil extraction chamber 3 to recoil the filter through the first impeller 7 and the second impeller 8.

[0065] In other embodiments, the sensing element may also be configured as a timer, and the timer is configured to record the running time of the fuel pump. When the time recorded by the timer reaches a preset time, it indicates that the blockage degree of the filter has reached a preset degree. At this time, the timer sends a signal to the motor 9 to reverse the motor 9 to drive the fuel in the oil extraction chamber 3 to recoil the filter through the first impeller 7 and the second impeller 8.

[0066] In some other embodiments, the combined fuel pump further includes a second elastic member, and the second elastic member is configured to drive the second oil inlet plate 5 to slide elastically along its own axial direction.

[0067] Specifically in this embodiment, the second elastic member is configured as a second compression spring 14, such as Figure 5 As shown, in order to facilitate the installation of the second compression spring 14, the pump cover 2 is configured as a two-step cylindrical structure. The second compression spring 14 is vertically arranged during installation, and the top end is fixedly connected to the bottom of the second oil inlet pan 5, and the bottom end is fixedly connected to the top of the step of the pump cover 2. Under the action of the second compression spring 14, the second oil inlet pan 5 has a tendency to move away from the partition 203, thereby facilitating the resetting of the second oil inlet pan 5 and the second impeller 8.

[0068] In other embodiments, a plurality of first rollers 15 are provided on the first impeller 7, the plurality of first rollers 15 are arranged circumferentially, the axis of the first rollers 15 is perpendicular to the axis of the first impeller 7, and the first rollers 15 and the first oil inlet plate 4 form a rolling fit.

[0069] Specifically in this embodiment, Figure 4 As shown, a plurality of first rollers 15 are evenly arranged along the circumferential direction to ensure the rationality of the structure; the arrangement of the first rollers 15 enables the friction between the first impeller 7 and the first oil inlet plate 4 to be in the form of rolling friction when rotating, thereby reducing the load of the motor 9 on the one hand and reducing the wear between the first impeller 7 and the first oil inlet plate 4 on the other hand.

[0070] In other embodiments, a plurality of second rollers 16 are provided on the second impeller 8, the plurality of second rollers 16 are arranged circumferentially, the axes of the second rollers 16 are perpendicular to the axis of the second impeller 8, and the second rollers 16 and the second oil inlet plate 5 form a rolling fit.

[0071] Specifically in this embodiment, Figure 4 As shown, a plurality of second rollers 16 are evenly arranged along the circumferential direction to ensure the rationality of the structure; the arrangement of the second rollers 16 enables the friction between the second impeller 8 and the second oil inlet plate 5 to be in the form of rolling friction when rotating, thereby reducing the load of the motor 9 on the one hand and reducing the wear between the second impeller 8 and the second oil inlet plate 5 on the other hand.

[0072] In other embodiments, the first impeller 7 and / or the second impeller 8 is / are made of ceramic material.

[0073] Specifically in this embodiment, the first impeller 7 and / or the second impeller 8 made of ceramic material have good wear resistance, corrosion resistance, low weight, high speed performance and good self-lubrication, thereby improving the performance of the first impeller 7 and / or the second impeller 8.

[0074] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0075] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A combined fuel pump, characterized in that: The combined fuel pump comprises a pump housing, a pump cover and an oil outlet are arranged on the pump housing, an oil inlet is arranged on the pump cover, an oil extraction chamber is formed between the pump cover and the pump housing, and the oil extraction chamber is communicated with the oil outlet and the oil inlet at the same time; a filter screen, a first oil inlet pan and a second oil inlet pan are sequentially inserted in the pump cover in a direction away from the oil inlet, the first oil inlet pan and the second oil inlet pan are coaxially arranged and each of them is provided with a plurality of first through holes, the first through holes are communicated with the oil inlet and the oil extraction chamber, and the first oil inlet pan and the second oil inlet pan can be arranged along their own axis elastically slide in the linear direction; a first impeller is installed in the first oil inlet tray, the first impeller can rotate around its own axis, the first impeller has a plurality of first blades, and the plurality of first blades are arranged along the circumferential direction; a motor is installed in the oil pumping chamber, the motor is configured to provide a driving force for the first impeller to rotate around its own axis; a second impeller is installed in the second oil inlet tray, the second impeller can rotate around its own axis, the second impeller has a plurality of second blades, the second blades and the first blades are arranged correspondingly, and partially overlap along the axial direction of the second impeller.

2. The combined fuel pump according to claim 1, characterized in that: A one-way valve is arranged at the oil outlet, and the opening direction of the one-way valve is configured to be from the oil pumping chamber to the oil outlet.

3. The combined fuel pump according to claim 2, characterized in that: The combined fuel pump also includes a sensing element, which is configured to sense the degree of blockage of the filter, and when the degree of blockage of the filter is greater than or equal to a preset degree, the sensing element is configured to send a signal to the motor to reverse the motor to drive the fuel in the oil extraction chamber to recoil the filter through the first impeller and the second impeller.

4. The combined fuel pump according to claim 3, characterized in that: The combined fuel pump further comprises a first elastic member, and the first elastic member is configured to drive the first oil inlet plate to slide elastically along its own axial direction.

5. The combined fuel pump according to claim 4, characterized in that: A first blocking portion is provided on the first blade, and a second blocking portion is provided on the second blade. The first blocking portion and the second blocking portion are matched with each other to enable the first impeller to synchronously drive the second impeller to move, thereby compressing the first elastic member; the sensing member is configured as a pressure sensor, and the pressure sensor is configured to sense the pressure change of the first elastic member to indirectly determine the degree of blockage of the filter.

6. The combined fuel pump according to claim 3, characterized in that: The sensing element is configured as a fluid pressure sensor, and the fluid pressure sensor is configured to sense the pressure inside the pump cover to indirectly determine the degree of clogging of the filter.

7. The combined fuel pump according to claim 1, characterized in that: The combined fuel pump further comprises a second elastic member, and the second elastic member is configured to drive the second oil inlet plate to slide elastically along its own axial direction.

8. The combined fuel pump according to claim 7, characterized in that: The second elastic member is a second compression spring, and is connected between the second oil inlet pan and the pump cover. Under the action of the second compression spring, the second oil inlet pan has a tendency to move in a direction away from the oil inlet.

9. The combined fuel pump according to claim 1, characterized in that: The first impeller is provided with a plurality of first rollers, which are arranged circumferentially, the axes of the first rollers and the axis of the first impeller are perpendicularly arranged, and the first rollers and the first oil inlet pan form a rolling fit.

10. The combined fuel pump according to claim 1, characterized in that: The first impeller and / or the second impeller are made of ceramic material.

Images