High-pressure common-rail oil supply pump

Abstract

The utility model discloses a high-pressure common rail fuel feed pump, which relates to the technical field of fuel pumps and comprises a pump body, a fuel delivery pump assembly, a cam shaft and two or more than two fuel pumping mechanisms, the cam shaft is of a symmetrical double-convex peach structure, the fuel pumping mechanisms are uniformly distributed on the periphery of the pump body in the circumferential direction, and a fuel inlet is formed in the pump body. A first oil duct communicated with the oil inlet and a second oil duct communicated with the first oil duct are arranged in the pump body, and a third oil duct communicated with the second oil duct is arranged in the oil pumping mechanism. The multiple oil pumping mechanisms are arranged on the same pump body in the circumferential direction, the single oil pumping mechanism can complete two times of oil pumping when the cam shafts of the symmetrical double-convex-peach structures rotate by one circle, the oil supply amount is remarkably increased, the phase difference of the symmetrical cams can offset oil pressure pulses, pressure oscillation in a high-pressure oil duct is reduced, it is guaranteed that oil supply of all cylinders of the multi-cylinder engine is uniform, and the service life of the engine is prolonged. Therefore, the oil supply pressure is stable, and the oil supply amount, the oil supply pressure and the stability of the large-displacement diesel engine can be met.

Description

TECHNICAL FIELD

[0001] The utility model relates to fuel pump technical field especially relates to a kind of high-pressure common rail oil supply pump. BACKGROUND

[0002] With the rapid development of industrial technology, multi-cylinder large displacement diesel engine is widely used in heavy transport, engineering machinery, marine power and generator set and other fields due to its high power output, fuel economy and reliability. The performance requirements of multi-cylinder large displacement diesel engine for fuel supply system are extremely strict, which requires stable high-pressure fuel supply in a wide speed range, while ensuring the stability of fuel supply quantity and pressure of each cylinder to meet the needs of combustion efficiency optimization and emission regulation upgrading.

[0003] However, the traditional fuel injection pump (such as inline pump or distributor pump) has problems of unstable fuel supply pressure and insufficient fuel supply when dealing with complex working conditions of large displacement and multi-cylinder engine. The traditional fuel injection pump usually adopts single plunger or single camshaft driving structure, and the reciprocating frequency of plunger structure is limited by camshaft speed. Under high speed or high load working condition, the plunger cannot quickly respond to the dynamic changes of fuel demand. For example, when the engine needs to instantaneously increase the fuel supply, the mechanical inertia of single plunger causes its motion lag, and the fuel supply cannot match the demand in time, causing fuel supply pressure fluctuation. In addition, single pump oil system design in multi-cylinder engine easily leads to insufficient fuel supply of each cylinder, especially under high speed or variable load working condition, the fuel distribution deviation increases, which will directly affect the power output stability and emission performance of the engine.

[0004] Therefore, it is urgent to develop a high-efficiency and stable high-pressure common rail oil supply pump to meet the performance requirements of multi-cylinder large displacement diesel engine in fuel supply quantity and fuel supply pressure stability. UTILITY MODEL CONTENTS

[0005] The utility model aims at providing a kind of high-pressure common rail oil supply pump, it can meet the performance requirements of multi-cylinder large displacement diesel engine in fuel supply quantity and fuel supply pressure stability.

[0006] To achieve the above-mentioned purpose, the utility model adopts the following technical scheme: a kind of high-pressure common rail oil supply pump, including pump body, the camshaft being rotationally arranged in the middle part of pump body and being arranged in pump body and the pump oil mechanism being fixed in the interior of pump body and the number being 2 and above, the camshaft is symmetrical double convex peach structure, the pump oil mechanism is evenly distributed in the four around pump body, the camshaft is used to drive pump oil mechanism and oil pump assembly movement, the oil inlet is opened on pump body.

[0007] The utility model discloses a technical principle as follows: the camshaft rotation one week single pump oil mechanism of symmetrical double convex peach structure can complete twice pumping, and the oil supply is increased obviously, and the phase difference of symmetrical cam can offset oil pressure pulse, reduce the pressure oscillation in high pressure oil channel, ensure that the oil supply of each cylinder of multi -cylinder engine is even, thereby make the oil supply pressure stable, and further can satisfy the oil supply of large -displacement diesel engine, oil supply pressure and stability.

[0008] Further, the first oil passage and the second oil passage communicated with the first oil passage are arranged in the pump body, the third oil passage communicated with the second oil passage is arranged in the pump oil mechanism, and the first cover plate for sealing the first oil passage is arranged on the pump body.

[0009] Further, the pump oil mechanism comprises a pump oil assembly and a roller body assembly, the camshaft drives the movement of the roller body assembly to drive the movement of the pump oil assembly, and the third oil passage is arranged in the pump oil assembly.

[0010] The pump oil assembly comprises:

[0011] The plunger sleeve is fixed in the pump body, and the low-pressure oil cavity, the high-pressure oil cavity, the plunger cavity and the oil injection cavity are formed in the plunger sleeve, and the third oil passage is communicated with the low-pressure oil cavity;

[0012] The plunger is slidably arranged in the plunger cavity and is used for pressurizing the fuel in the high-pressure oil cavity;

[0013] The oil inlet part is arranged in the low-pressure oil cavity and is used for sealing or communicating the low-pressure oil cavity and the high-pressure oil cavity;

[0014] The oil outlet part is arranged in the oil injection cavity and is used for sealing or communicating the high-pressure oil cavity and the oil injection cavity.

[0015] Further, the oil inlet part comprises:

[0016] The oil inlet valve body is fixedly installed in the low-pressure oil cavity, the fourth oil passage communicated with the low-pressure oil cavity and the high-pressure oil cavity is formed in the oil inlet valve body, and the oil inlet valve core for sealing the fourth oil passage is slidably arranged in the oil inlet valve body;

[0017] The plug is fixedly installed in the low-pressure oil cavity and abuts against the oil inlet valve body, the plug is used for sealing the low-pressure oil cavity, the installation cavity is formed in the plug, the oil inlet valve spring is arranged in the installation cavity, the first spring seat arranged in the installation cavity is fixedly installed on the oil inlet valve core, and the first spring seat is fixedly installed on the oil inlet valve spring.

[0018] Further, the oil outlet part comprises a second spring seat fixedly installed in the oil injection cavity, an oil outlet valve core slidingly arranged in the oil injection cavity, and an oil outlet valve spring arranged between the second spring seat and the oil outlet valve core, the second spring seat is in interference fit with the oil injection cavity, the oil outlet valve core is in clearance fit with the oil injection cavity, the second spring seat is provided with an oil injection hole in the axial direction, and the circumferential side wall of the oil outlet valve core is provided with a communication hole, and the oil outlet valve core is used for closing or conducting the high-pressure oil cavity and the oil injection cavity.

[0019] Further, the roller body assembly comprises a roller body, a roller rotatingly installed on the roller body and abutting against the cam shaft, a plunger spring lower seat arranged in the roller body, and a plunger spring arranged on the plunger spring lower seat and coaxially sleeved outside the plunger sleeve, the plunger is arranged on the plunger spring lower seat, the side wall of the roller body is provided with a guide groove, the pump body is provided with a mounting hole, a guide pin is fixedly installed in the mounting hole and arranged in the guide groove.

[0020] Further, the plunger sleeve is provided with a lubricating cavity and a fifth oil channel communicating the low-pressure oil cavity and the lubricating cavity, the lubricating cavity is provided with an oil seal and an oil seal seat, the oil seal is coaxially sleeved outside the plunger, and the oil seal seat is coaxially sleeved outside the oil seal.

[0021] Further, the cam shaft is sleeved with a sliding bearing, the sliding bearing is provided with a first oil hole, the roller body is provided with a second oil hole, the pump body is provided with an oil inlet, the pump body is provided with a second cover plate provided with an oil outlet, the pump body is provided with a first oil channel communicating the oil inlet and the oil hole, a second oil channel communicating the first oil channel, and a third oil channel communicating the second oil channel and the second oil hole.

[0022] Further, the pump body is provided with an oil inlet metering valve assembly and an oil delivery pump assembly coaxially arranged on the pump body, the oil inlet metering valve assembly is arranged between the oil inlet and the first oil channel, and the cam shaft 11 is further used for driving the oil delivery pump assembly 2 to move.

[0023] Further, the pump body is further provided with an oil outlet communicating the first oil channel, and the oil outlet is provided with a flow limiting valve.

[0024] The utility model discloses beneficial effects are:

[0025] 1. By setting multiple pump oil mechanisms on the same pump body, the single pump oil mechanism can complete twice pumping when the cam shaft of the symmetrical double convex peach structure rotates a circle, the oil supply amount is significantly increased, the phase difference of the symmetrical cam can offset the oil pressure pulse, the pressure shock in the high-pressure oil channel is reduced, the oil supply of each cylinder of the multi-cylinder engine is uniform, thereby the oil supply pressure is stable, and the oil supply amount, oil supply pressure and stability of the large displacement diesel engine can be met.

[0026] 2. By setting the fifth oil channel, the oil seal and the oil seal seat, the plunger can be lubricated by diesel oil in the pump body, and diesel oil leakage to the cam shaft can be prevented, without the need for an additional lubricating mechanism.

[0027] 3、By the first oil channel, the second oil channel, the first oil hole and the second oil hole, the engine oil can lubricate the camshaft and the roller body assembly at the same time, so as to improve the service life of the device. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 is the axial view of the structure of the utility model;

[0029] Figure 2 is the top view of the utility model;

[0030] Figure 3 is the Figure 2 sectional view along direction A-A;

[0031] Figure 4 is the Figure 2 sectional view along direction B-B;

[0032] Figure 5 is the axial view of the pump body in the utility model;

[0033] Figure 6 is the rear view of the pump body in the utility model;

[0034] Figure 7 is the sectional view of the pump body in the utility model;

[0035] Figure 8 is the perspective view of the plunger sleeve in the utility model;

[0036] Figure 9 is the sectional view of the pump oil mechanism in the utility model;

[0037] Figure 10 is the Figure 9 enlarged view of A;

[0038] Figure 11 is the internal structure diagram of the utility model;

[0039] Figure 12 is the axial view of the second cover plate in the utility model.

[0040] In the above drawings:

[0041] 1, pump body; 101, oil inlet; 102, first oil channel; 103, second oil channel; 104, oil outlet; 105, engine oil inlet; 106, first oil channel; 107, second oil channel; 108, third oil channel; 109, engine oil outlet; 110, mounting hole;

[0042] 2, oil pump assembly; 3, oil inlet metering valve assembly; 4, flow limiting valve;

[0043] 5, pump oil assembly; 501, plunger sleeve; 5011, low pressure oil cavity; 5012, high pressure oil cavity; 5013, plunger cavity; 5014, injection oil cavity; 5015, third oil channel; 5016, lubricating cavity; 5017, fifth oil channel; 502, plunger;

[0044] 6, oil inlet part; 601, oil inlet valve body; 6011, fourth oil channel; 602, oil inlet valve core; 603, plug; 6031, installation cavity; 604, oil inlet valve spring; 605, first spring seat;

[0045] 7, oil outlet part; 701, second spring seat; 7011, injection hole; 702, oil outlet valve core; 7021, communication hole; 703, oil outlet valve spring;

[0046] 8, roller body assembly; 801, roller body; 8011, second oil hole; 8012, guide groove; 802, roller; 803, plunger spring lower seat; 804, guide pin; 805, plunger spring;

[0047] 9, oil seal; 10, oil seal seat;

[0048] 11, camshaft;

[0049] 12, sliding bearing; 1201, first oil hole;

[0050] 13, first cover plate; 14, second cover plate; 15, gear. DETAILED DESCRIPTION

[0051] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. The structures described in various embodiments can be freely combined without structural or principle conflicts.

[0052] In the utility model, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connecting", "fixing" and the like should be understood broadly, for example, can be fixed connection, or can be detachable connection, or can be integrated; can be mechanical connection, or can be electrical connection; can be directly connected, or can be indirectly connected through intermediate medium, can be the communication inside two elements or the interaction relationship between two elements. For ordinary skilled in the art, the specific meaning of the above terms in the utility model can be understood according to specific circumstances.

[0053] In the description of the utility model, it needs to explain, the terms "center", "upper", "lower", "left", "right", "internal", "external" and so on indicate the orientation or position relation is based on the orientation or position relation shown in the drawing, or it is the orientation or position relation that the utility model product uses usually places, only is for the convenience of describing the utility model and simplifying the description, and cannot indicate or imply that the indicated device or element must have a particular orientation, constructs and operates with a particular orientation, therefore cannot be understood as the limitation to the utility model. In addition, the terms "first", "second" and so on are only used for distinguishing description, and cannot be understood as indicating or implying relative importance.

[0054] The utility model discloses some embodiments in combination with the drawings as follows:

[0055] As Figures 1-9 The utility model provides a high pressure common rail oil supply pump, including pump body 1, set up in pump body 1 and rotate the camshaft 11 of setting in the middle part of pump body 1 and with pump body 1 inside fixed and the number is 2 and more than pump oil mechanism, camshaft 11 is symmetrical double convex peach structure, and pump oil mechanism is evenly distributed in the four around of pump body 1, and camshaft 11 is used to drive pump oil mechanism movement, and pump body 1 is opened and has the oil inlet 101, and pump body 1 is provided with the first oil channel 102 of communicating with the oil inlet 101 and the second oil channel 103 of communicating with the first oil channel 102, and pump oil mechanism is provided with the third oil channel 5015 of communicating with the second oil channel 103, and pump body 1 is provided with the first cover plate 13 for sealing the first oil channel 102.

[0056] The first oil channel 102 is the total oil channel, for the convenience to different pump oil mechanism delivery fuel, and the first oil channel 102 is annular oil channel with camshaft 11 as the center, and the first oil channel 102 is set up in the surface of pump body 1 near oil pump assembly 2 side, and first sealing ring 14 is arranged between first cover plate 13 and pump body 1. The second oil channel 103 is arranged in the pump body 1, and is a branch oil channel in the pump body 1 leading to different pump oil mechanisms. The third oil channel 5015 is an oil channel connecting the pump oil mechanism and the pump body 1.

[0057] The number of pump oil mechanisms is at least two, and can also be three, four, five, etc., and the pump oil mechanisms are circumferentially distributed on the pump body 1. The central axes of the pump oil mechanisms are perpendicular to the central axis of the camshaft 11. When the number of pump oil mechanisms is three, the included angle between the central axes of each adjacent two pump oil mechanisms is 120°. When the number of pump oil mechanisms is four, the included angle between the central axes of each adjacent two pump oil mechanisms is 90°. When the number of pump oil mechanisms is five, the included angle between the central axes of each adjacent two pump oil mechanisms is 72°. And so on.

[0058] The number of the second oil channels 103 is equal to the number of the pump oil mechanisms, so that each pump oil mechanism has a separate branch oil channel for oil supply. In order to ensure the oil supply amount, oil supply pressure and stability of the diesel engine, the pump oil mechanisms are preferably three in number.

[0059] The camshaft 11 is a symmetrical double-convex cam structure, and the double-convex cam refers to the design of two convex parts (i.e. cams) on the surface of the camshaft 11, each of which corresponds to the reciprocating motion of a plunger 502. The symmetrical double-convex cam structure refers to the complete symmetry of the shape, height and phase angle of the two cams. The camshaft 11 can also be a multi-convex cam structure, such as a triple-convex cam structure, and the double-convex cam structure is preferred. Through the design of the cam profile, the cam lift is a smooth curve (sine shape), which can work smoothly at high speed. When the camshaft 11 rotates one revolution, the two cams are symmetrically distributed at 180°, which ensures the balance of the motion trajectory and the force. The camshaft 11 is fixedly installed with a gear 15 for driving the motion of the camshaft 11. By setting gears 15 of different sizes, the rotation speed of the camshaft 11 can be easily controlled, so that the pump oil rate of the fuel pump can be easily controlled.

[0060] After the diesel enters the pump body 1, it enters different pump oil mechanisms through the first oil channel 102, the second oil channel 103 and the third oil channel 5015. Compared with a single camshaft that can only complete one pumping per revolution, the double-convex camshaft can complete two pumpings per revolution, which can significantly increase the oil supply amount. The phase difference of the symmetrical cams can offset the oil pressure pulse and reduce the pressure shock in the high-pressure oil channel, ensuring uniform oil supply for each cylinder of the multi-cylinder engine, thereby stabilizing the oil supply pressure and meeting the oil supply amount, oil supply pressure and stability of the large-displacement diesel engine. At the same time, the symmetrical layout can reduce the inertial impact and vibration of the camshaft 11 during rotation, prolonging the service life of the fuel pump.

[0061] The plurality of pump oil mechanisms are circumferentially arranged on the pump body 1, which can make the fuel pump more compact.

[0062] Further, as shown in Figure 1 , Figure 3 , Figure 4 , Figure 9 and Figure 10 , the pump oil mechanism includes a pump oil assembly 5 and a roller body assembly 8, the camshaft 11 drives the motion of the roller body assembly 8 to drive the motion of the pump oil assembly 5, and the third oil channel 5015 is arranged in the pump oil assembly 5.

[0063] The pump oil assembly 5 includes:

[0064] A plunger sleeve 501 is fixedly arranged in the pump body 1, and the plunger sleeve 501 is provided with a low-pressure oil cavity 5011, a high-pressure oil cavity 5012, a plunger cavity 5013 and an injection cavity 5014, and the third oil channel 5015 is in communication with the low-pressure oil cavity 5011.

[0065] a plunger 502 slidingly arranged in the plunger cavity 5013 for pressurizing the fuel in the high-pressure fuel cavity 5012;

[0066] an oil inlet portion 6 arranged in the low-pressure fuel cavity 5011 for sealing or connecting the low-pressure fuel cavity 5011 and the high-pressure fuel cavity 5012;

[0067] an oil outlet portion 7 arranged in the fuel injection cavity 5014 for sealing or connecting the high-pressure fuel cavity 5012 and the fuel injection cavity 5014.

[0068] The oil inlet portion 6 comprises:

[0069] an oil inlet valve body 601 fixedly arranged in the low-pressure fuel cavity 5011, the oil inlet valve body 601 having a fourth oil passage 6011 formed therein for connecting the low-pressure fuel cavity 5011 and the high-pressure fuel cavity 5012, and an oil inlet valve spool 602 slidingly arranged in the oil inlet valve body 601 for sealing the fourth oil passage 6011;

[0070] a plug 603 fixedly arranged in the low-pressure fuel cavity 5011 and abutting against the oil inlet valve body 601, the plug 603 being used for sealing the low-pressure fuel cavity 5011, the plug 603 having an installation cavity 6031 formed therein, an oil inlet valve spring 604 being arranged in the installation cavity 6031, a first spring seat 605 being fixedly arranged on the oil inlet valve spool 602 and arranged in the installation cavity 6031, and the first spring seat 605 being fixedly arranged on the oil inlet valve spring 604.

[0071] The oil outlet portion 7 comprises a second spring seat 701 fixedly arranged in the fuel injection cavity 5014, an oil outlet valve spool 702 slidingly arranged in the fuel injection cavity 5014, an oil outlet valve spring 703 arranged between the second spring seat 701 and the oil outlet valve spool 702, the second spring seat 701 being in interference fit with the fuel injection cavity 5014, the oil outlet valve spool 702 being in clearance fit with the fuel injection cavity 5014, the second spring seat 701 having a fuel injection hole 7011 formed in the axial direction thereof, the oil outlet valve spool 702 having a through hole 7021 formed in the circumferential side wall thereof, and the oil outlet valve spool 702 being used for sealing or connecting the high-pressure fuel cavity 5012 and the fuel injection cavity 5014.

[0072] The roller body assembly 8 comprises a roller body 801, a roller 802 rotatably arranged on the roller body 801 and abutting against the cam shaft 11, a plunger spring lower seat 803 arranged in the roller body 801, and a plunger spring 805 arranged on the plunger spring lower seat 803 and coaxially sleeved on the plunger sleeve 501, the plunger 502 being arranged on the plunger spring lower seat 803, the side wall of the roller body 801 having a guide groove 8012 formed therein, the pump body 1 having an installation hole 110 formed therein, and a guide pin 804 being fixedly arranged in the installation hole 110 and arranged in the guide groove 8012.

[0073] Oil inlet process: the oil pump continuously supplies fuel to the low pressure oil chamber 5011, the roller 802 always abuts against the cam shaft 11, the cam shaft 11 rotates to make the plunger 502 descend in the plunger chamber 5013 under the action of the roller body assembly 8, a negative pressure is formed in the high pressure oil chamber 5012, at this time, a pressure difference is formed between the low pressure oil chamber 5011 and the high pressure oil chamber 5012, the oil inlet valve core 602 moves downward against the elastic force of the oil inlet valve spring 604, the fuel in the low pressure oil chamber 5011 is sucked into the high pressure oil chamber 5012 through the fourth oil passage 6011, until the high pressure oil chamber 5012 is filled with fuel, at this time, the pressure difference between the high pressure oil chamber 5012 and the low pressure oil chamber 5011 disappears, the oil inlet valve core 602 rises under the action of the oil inlet valve spring 604, the fourth oil passage 6011 is blocked, the high pressure oil chamber 5012 is cut off from the low pressure oil chamber 5011, and the oil inlet process stops.

[0074] Oil outlet process: the cam shaft 11 rotates to make the plunger 502 ascend in the plunger chamber 5013 under the action of the roller body assembly 8, the volume of the sealed high pressure oil chamber 5012 gradually decreases, the fuel inside is compressed, and the pressure rapidly rises, when the pressure of the high pressure oil chamber 5012 exceeds the sum of the elastic force of the oil outlet valve spring 703 and the pressure of the high pressure common rail pipe outside the injection chamber 5014, the oil outlet valve spring 703 is compressed, driving the oil outlet valve core 702 to move synchronously, the high pressure fuel in the high pressure oil chamber 5012 enters the injection chamber 5014, and then is pumped out through the connecting hole and the injection hole 7011, and enters the high pressure oil pipe outside the pump body 1. After the fuel is pumped out, the pressure in the high pressure oil chamber 5012 decreases, when the pressure is lower than the elastic force of the oil outlet valve spring 703, the oil outlet valve core 702 resets to seal the high pressure oil chamber 5012 again under the action of the oil outlet valve spring 703, and the oil outlet process ends, returning to the oil inlet process again.

[0075] Through the setting of the guide pin 804, the roller body 801 can be limited and guided, ensuring the stability of the operation of the device.

[0076] Further, as shown in Figure 8 , the plunger sleeve 501 is provided with a lubricating chamber 5016 and a fifth oil passage 5017 connecting the low pressure oil chamber 5011 and the lubricating chamber 5016, and the lubricating chamber 5016 is provided with an oil seal 9 and an oil seal seat 10, the oil seal 9 is coaxially sleeved outside the plunger 502, and the oil seal seat 10 is coaxially sleeved outside the oil seal 9.

[0077] The fuel in the low pressure oil chamber 5011 can enter the lubricating chamber 5016 through the fifth oil passage 5017, the plunger 502 is lubricated by diesel oil inside the pump body 1, and the lubricating chamber 5016 can be sealed under the action of the oil seal 9 and the oil seal seat 10, avoiding fuel leakage to the cam shaft 11.

[0078] Further, as shown in Figure 1 , Figure 5, Figure 6 , Figure 7 , Figure 11 and Figure 12 As shown, a sliding bearing 12 is sleeved on the camshaft 11, and a first oil hole 1201 is opened on the sliding bearing 12. A second oil hole 8011 is opened on the roller body 801. An oil inlet 105 is opened on the pump body 1. A second cover plate 14 with an oil outlet 109 is provided on the pump body 1. A first oil passage 106 is opened inside the pump body 1, which is connected to both the oil inlet and the first oil hole 1201. A second oil passage 107 is connected to the first oil passage 106. A third oil passage 108 is connected to the second oil passage 107 and the second oil hole 8011.

[0079] The first oil passage 106 is located inside the pump body 1, and the second oil passage 107 is located on the surface of the pump body 1 away from the oil pump. To facilitate the delivery of oil to different roller assembly 8, the second oil passage 107 is an annular oil passage with the camshaft 11 as the center. The pump body 1 is provided with a second cover plate 14 for sealing the second oil passage 107, and a second sealing ring 16 is provided between the second cover plate 14 and the pump body 1. The number of third oil passages 108 is equal to the number of pumping mechanisms, ensuring that each roller assembly 8 can be lubricated.

[0080] Furthermore, such as Figure 1 As shown, the pump body 1 is provided with an oil inlet metering valve assembly 3 and an oil delivery pump assembly 2 coaxially arranged with the pump body 1. The oil inlet metering valve assembly 3 is located between the oil inlet 101 and the first oil passage 102. The camshaft 11 is also used to drive the oil delivery pump assembly 2 to move.

[0081] The oil inlet metering valve assembly 3 allows for adjustment of the oil inlet flow rate. Integrating the oil transfer pump assembly 2 onto the oil supply pump reduces the footprint of the oil supply pump.

[0082] Furthermore, such as Figure 1 As shown, the pump body 1 also has an oil outlet 104 that communicates with the first oil passage 102, and a flow limiting valve 4 is installed at the oil outlet 104.

[0083] When the pressure in the first oil passage 102 is too high, the flow limiting valve 4 opens, releasing some fuel to flow into the return oil line, thereby enabling the fuel in the oil pump to be maintained within a stable pressure range.

Claims

1. A high-pressure common rail oil supply pump, characterized in that: It includes a pump body (1), a camshaft (11) disposed inside the pump body (1) and rotatably disposed in the middle of the pump body (1), and two or more pumping mechanisms fixed inside the pump body (1). The camshaft (11) has a symmetrical double-convex structure. The pumping mechanisms are evenly distributed around the pump body (1). The camshaft (11) is used to drive the pumping mechanism to move. An oil inlet (101) is opened on the pump body (1).

2. The high-pressure common rail oil pump according to claim 1, characterized in that, The pump body (1) is provided with a first oil passage (102) communicating with the oil inlet (101) and a second oil passage (103) communicating with the first oil passage (102). The pump mechanism is provided with a third oil passage (5015) communicating with the second oil passage (103). The pump body (1) is provided with a first cover plate (13) for sealing the first oil passage (102).

3. A high-pressure common rail oil pump according to claim 2, characterized in that, The oil pumping mechanism includes an oil pumping assembly (5) and a roller assembly (8). The camshaft (11) drives the roller assembly (8) to move, thereby driving the oil pumping assembly (5) to move. The third oil passage (5015) is located inside the oil pumping assembly (5). The oil pump assembly (5) includes: The plunger sleeve (501) is fixed inside the pump body (1). The plunger sleeve (501) has a low-pressure oil chamber (5011), a high-pressure oil chamber (5012), a plunger chamber (5013) and an injection chamber (5014). The third oil passage (5015) is connected to the low-pressure oil chamber (5011). A plunger (502) is slidably disposed in a plunger cavity (5013) for pressurizing the fuel in the high-pressure oil cavity (5012); The oil inlet (6) is located in the low-pressure oil chamber (5011) and is used to seal or connect the low-pressure oil chamber (5011) and the high-pressure oil chamber (5012). The oil outlet (7) is located inside the oil injection chamber (5014) and is used to seal or connect the high-pressure oil chamber (5012) and the oil injection chamber (5014).

4. A high-pressure common rail oil pump according to claim 3, characterized in that, The oil inlet (6) includes: An oil inlet valve body (601) is fixedly installed in a low-pressure oil chamber (5011). A fourth oil passage (6011) is opened in the oil inlet valve body (601) to connect the low-pressure oil chamber (5011) and the high-pressure oil chamber (5012). An oil inlet valve core (602) for sealing the fourth oil passage (6011) is slidably arranged in the oil inlet valve body (601). A plug (603) is fixedly installed in the low-pressure oil chamber (5011) and abuts against the oil inlet valve body (601). The plug (603) is used to seal the low-pressure oil chamber (5011). An installation cavity (6031) is opened in the plug (603). An oil inlet valve spring (604) is provided in the installation cavity (6031). A first spring seat (605) is fixedly installed on the oil inlet valve core (602) and is provided in the installation cavity (6031). The first spring seat (605) is fixedly installed on the oil inlet valve spring (604).

5. A high-pressure common rail oil pump according to claim 3 or 4, characterized in that, The oil outlet section (7) includes a second spring seat (701) fixedly installed in the oil injection chamber (5014), an oil outlet valve core (702) slidably installed in the oil injection chamber (5014), and an oil outlet valve spring (703) disposed between the second spring seat (701) and the oil outlet valve core (702). The second spring seat (701) is interference-fitted with the oil injection chamber (5014), and the oil outlet valve core (702) is clearance-fitted with the oil injection chamber (5014). An oil injection hole (7011) is opened in the axial direction of the second spring seat (701), and a connecting hole (7021) is opened on the circumferential side wall of the oil outlet valve core (702). The oil outlet valve core (702) is used to seal or connect the high-pressure oil chamber (5012) and the oil injection chamber (5014).

6. A high-pressure common rail oil supply pump according to claim 3 or 4, characterized in that, The roller assembly (8) includes a roller body (801), a roller (802) rotatably mounted on the roller body (801) and abutting against the camshaft (11), a plunger spring lower seat (803) disposed in the roller body (801), and a plunger spring (805) disposed on the plunger spring lower seat (803) and coaxially sleeved outside the plunger sleeve (501). The plunger (502) is disposed on the plunger spring lower seat (803). A guide groove (8012) is opened on the side wall of the roller body (801). A mounting hole (110) is opened on the pump body (1). A guide pin (804) is fixedly installed in the mounting hole (110), and the guide pin (804) is disposed in the guide groove (8012).

7. A high-pressure common rail oil supply pump according to claim 3 or 4, characterized in that, The plunger sleeve (501) has a lubrication chamber (5016) and a fifth oil passage (5017) connecting the low-pressure oil chamber (5011) and the lubrication chamber (5016). The lubrication chamber (5016) is provided with an oil seal (9) and an oil seal seat (10). The oil seal (9) is coaxially sleeved outside the plunger (502), and the oil seal seat (10) is coaxially sleeved outside the oil seal (9).

8. A high-pressure common rail oil pump according to claim 6, characterized in that, A sliding bearing (12) with a first oil hole (1201) is fitted on the camshaft (11), a second oil hole (8011) is opened on the roller body (801), an oil inlet (105) is opened on the pump body (1), a second cover plate (14) with an oil outlet (109) is provided on the pump body (1), and a first oil passage (106) connected to both the oil inlet and the oil hole, a second oil passage (107) connected to the first oil passage (106), and a third oil passage (108) connected to the second oil passage (107) and the second oil hole (8011) are opened inside the pump body (1).

9. A high-pressure common rail oil pump according to claim 1, 2, 3, 4 or 8, characterized in that, The pump body (1) is provided with an oil metering valve assembly (3) and an oil pump assembly (2) coaxially arranged with the pump body (1). The oil metering valve assembly (3) is located between the oil inlet (101) and the first oil passage (102). The camshaft (11) is also used to drive the oil pump assembly (2) to move.

10. A high-pressure common rail oil supply pump according to claim 1, 2, 3, 4 or 8, characterized in that, The pump body (1) also has an oil outlet (104) that communicates with the first oil passage (102), and a flow limiting valve (4) is installed at the oil outlet (104).

Images