CN211144676U

CN211144676U - Energy accumulator and fuel system

Info

Publication number: CN211144676U
Application number: CN201921829933.6U
Authority: CN
Inventors: 鄢岚; 杨涛; 林琳; 浦卫华; 梁刚
Original assignee: 711th Research Institute of CSIC
Current assignee: 711th Research Institute of CSIC
Priority date: 2019-10-28
Filing date: 2019-10-28
Publication date: 2020-07-31
Anticipated expiration: 2029-10-28

Abstract

The utility model discloses an energy storage ware and fuel oil system. The fuel oil system comprises a fuel oil pump and an oil inlet pipe, the energy accumulator comprises a body and a diaphragm, a cavity is arranged inside the body, the body comprises a first wall, a second wall and a ring wall, the first wall is provided with an energy storage oil inlet, the energy storage oil inlet is communicated with the fluid of the oil inlet pipe, the ring wall is arranged around the circumferential direction of the body, the diaphragm is arranged inside the body and connected with the ring wall, the diaphragm separates the cavity into an oil cavity chamber and an air cavity chamber along the axial direction, the oil cavity chamber is communicated with the energy storage oil inlet, gas is filled in the air cavity chamber, and the diaphragm is deformable to change the volume of the oil cavity chamber so as to adjust the pressure. According to the utility model discloses an energy storage ware, diaphragm can separate the cavity for oil pocket and gas pocket, and the fuel can be filled in the oil pocket, and gas can be filled in the gas pocket, utilizes gaseous compressibility to store the fuel, when the fuel pressure production in advancing the oil pipe changes, can effectively absorb fuel pressure oscillation.

Description

Energy accumulator and fuel system

Technical Field

The utility model belongs to the technical field of fuel oil system, specifically relate to an energy storage ware and fuel oil system.

Background

The fuel oil system is one of the important auxiliary systems of the marine medium-speed diesel engine, and the main function of the fuel oil system is to provide an oil source for a high-pressure fuel oil pump and meet the fuel oil output with different flow rates under the same pressure point, so that the diesel engine can work normally, reliably and economically.

In the operation process of the existing diesel engine adopting the fuel pump, the volume of an oil cavity of the high-pressure fuel pump can change along with the change of a crankshaft angle, so that the pressure at two ends of the high-pressure oil pipe and the pressure at a pump end and a fuel injection nozzle end are changed. In general, orifice type pressure regulating valves are used for line pressure regulation in fuel systems. Because the throttling hole diameter is fixed, the flow of fuel in the whole system is an unstable process, which causes the pressure of the fuel in a low working condition to be inconsistent with the pressure of the fuel in a high working condition when the fuel enters a high-pressure fuel pump, and finally causes the pressure of the fuel in a fuel system to generate pulses.

The pressure pulse of the fuel cannot be eliminated fundamentally due to the limitation of structural characteristics, if the pressure pulse is transmitted to an oil inlet pressure sensor on a fuel system, the test value of the pressure sensor fluctuates violently, the pressure amplitude change can reach 13bar, the monitoring effect and result judgment are influenced, and the service life of the sensor is also influenced.

Therefore, it is desirable to provide an accumulator and a fuel system to at least partially solve the above technical problems.

SUMMERY OF THE UTILITY MODEL

In the summary section a series of concepts in a simplified form is introduced, which will be described in further detail in the detailed description section. The inventive content does not imply any attempt to define the essential features and essential features of the claimed solution, nor is it implied to be intended to define the scope of the claimed solution.

In order to solve the above-mentioned problem at least partially, the utility model discloses an energy accumulator for fuel oil system, fuel oil system include the fuel pump and with the oil pipe that advances of fuel pump fluid intercommunication, advance the oil pipe and be used for advancing the fuel and carry into in the fuel pump, the energy accumulator sets up the upper reaches of fuel pump, the energy accumulator includes:

the body, the inside of body is provided with the cavity, the body includes:

the first wall and the second wall are oppositely arranged along the axial direction of the energy accumulator, the first wall is provided with an energy storage oil inlet, and the energy storage oil inlet is communicated with the oil inlet pipe in a fluid mode;

the annular wall is arranged around the circumferential direction of the body, and two opposite sides of the annular wall are respectively connected with the first wall and the second wall; and

the diaphragm is arranged inside the body and connected with the annular wall, the diaphragm divides the cavity into an oil chamber and a gas chamber along the axial direction, the oil chamber is communicated with the energy storage oil inlet, gas is filled in the gas chamber, and the diaphragm is deformable to change the volume of the oil chamber so as to adjust the pressure of the fuel.

According to the utility model discloses an energy accumulator, energy accumulator include body and diaphragm, and the inside of body is provided with the cavity, and the diaphragm can separate the cavity for oil pocket room and air cavity room, and the fuel can be filled in the oil pocket room, and gas can be filled in the air cavity room, and the diaphragm structure is the volume in order to change the oil pocket room for deformable, utilizes gaseous compressibility to store the fuel, when the fuel pressure production in advancing the oil pipe changes, can the effective absorption fuel pressure oscillation.

Optionally, the diaphragm is provided with a blocking portion, the blocking portion is arranged opposite to the energy storage oil inlet, and when the pressure of the gas in the gas chamber is greater than the pressure of the fuel oil in the oil chamber, the blocking portion moves towards the energy storage oil inlet. Thus, the pressure fluctuation of the fuel can be effectively absorbed

Optionally, when the diaphragm is tightly attached to the first wall, the blocking portion closes the energy storage oil inlet. Thereby preventing the diaphragm from being damaged.

Optionally, the second wall is provided with an air inlet and a closure for sealing the air inlet. This avoids gas leakage.

Optionally, a step portion protruding inwards in the radial direction of the energy accumulator is formed on the annular wall, and the diaphragm is located between the step portion and the energy storage oil inlet. In this way, the structural strength of the annular wall is facilitated to be increased.

The utility model also provides a fuel oil system, fuel oil system includes the fuel pump, advances oil pipe and foretell energy storage ware.

According to the utility model discloses a fuel oil system, fuel oil system include foretell energy storage ware, and the energy storage ware includes body and diaphragm, and the inside of body is provided with the cavity, and the diaphragm can separate the cavity for oil pocket room and gas cavity room, and the fuel can be filled in the oil pocket room, and gas can be filled in the gas cavity room, and the diaphragm structure is the volume in order to change the oil cavity room for deformable, utilizes gaseous compressibility to store the fuel. Therefore, when the pressure of the fuel in the fuel inlet pipe changes, the pressure fluctuation of the fuel can be effectively absorbed.

Optionally, the fuel system still includes pressure regulator and oil pipe, the fuel pump is provided with the fuel pump oil-out, the pressure regulator is used for connecting the fuel pump oil-out with oil pipe. Therefore, the pressure regulator can balance the pressure of the fuel discharged from the fuel pump, the pressure of the fuel is balanced to a set value, the pressure values of the fuel pressure in the fuel system under different flow rates are kept consistent, and the design requirement of the system is met.

Optionally, the voltage regulator comprises:

a housing, the casing has pressure regulating oil inlet and pressure regulating oil-out, the pressure regulating oil inlet with fuel pump oil-out fluid intercommunication, the casing still includes:

the first cavity is communicated with the pressure regulating oil inlet;

the second cavity is communicated with the pressure regulating oil outlet in a fluid mode, and the axis of the second cavity is perpendicular to the axis of the first cavity;

the third cavity is arranged on the opposite side of the second cavity to the first cavity, and the axis of the third cavity is parallel to the axis of the first cavity; and

a piston, at least a portion of which is disposed in the third cavity, and which is movable relative to the housing in an axial direction of the third cavity,

when the piston moves to a preset position in the direction away from the pressure regulating oil inlet, the first cavity is communicated with the second cavity.

In this way, the fuel pressure can be effectively equalized.

Optionally, one side of the shell opposite to the pressure regulating oil inlet is provided with a cover body, the piston is provided with a groove, an opening of the groove faces the cover body, a spring is arranged between the groove and the cover body, one end of the spring abuts against the cover body, and the other end of the spring abuts against the groove. Therefore, the oil pump works by balancing the spring force of the spring and the acting force generated by the pressure of the fuel oil in the pressure regulating oil inlet.

Optionally, an adjusting screw is disposed on the cover body, the adjusting screw is movable relative to the cover body along an axial direction of the third cavity, and an inner end of the adjusting screw located in the housing abuts against the one end of the spring. Thus, the elastic force of the spring is adjusted.

Drawings

The following drawings of the embodiments of the present invention are provided as a part of the present invention for understanding the present invention. There are shown in the drawings, embodiments and descriptions thereof, which are used to explain the principles of the invention. In the drawings, there is shown in the drawings,

FIG. 1 is a schematic diagram of a fuel system according to a preferred embodiment of the present invention;

fig. 2 is a cross-sectional view of an accumulator according to a preferred embodiment of the present invention; and

FIG. 3 is a cross-sectional view of a pressure regulator of the fuel system shown in FIG. 1.

Description of reference numerals:

100: the fuel system 101: fuel pump

102: an oil injector 103: alarm sensor

104: the voltage regulator 105: one-way valve

106: the high-pressure oil pipe 107: fuel oil delivery pump

108: duplex filter 109: energy accumulator

110: temperature sensor 111: pressure sensor

112: the fuel inlet interface 113: fuel outlet interface

114: an oil inlet pipe 115: oil outlet pipe

120: a body 121: first wall

122: second wall 123: circular wall

124: energy storage oil inlet 125: interface part

126: oil passage 127: closure member

128: step 130: diaphragm

131: the plugging portion 141: oil chamber

142: the gas chamber 150: shell body

151: pressure regulating oil inlet 152: pressure regulating oil outlet

153: first cavity 154: second cavity

155: third cavity 156: first sub-chamber

157: the diversion chamber 160: piston

161: first groove 162: second concave part

170: cover 171: spring

172: the adjusting screw 173: adjusting nut

174: the bolting portion 175: second groove

Detailed Description

In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. It will be apparent, however, to one skilled in the art, that embodiments of the invention may be practiced without one or more of these specific details. In other instances, well-known features have not been described in order to avoid obscuring embodiments of the present invention.

In the following description, a detailed structure will be presented for a thorough understanding of embodiments of the invention. It is apparent that the implementation of the embodiments of the present invention is not limited to the specific details familiar to those skilled in the art.

Fig. 1 shows a schematic diagram of a fuel system 100 according to a preferred embodiment of the present invention.

The fuel system 100 generally includes a fuel pump 101, a fuel injector 102, a high pressure fuel line 106, a fuel inlet port 112, a fuel outlet port 113, a fuel inlet line 114, and a fuel outlet line 115, the fuel inlet port 112 being configured to deliver fuel, the fuel inlet port 112 being in fluid communication with the fuel inlet line 114, and the fuel being capable of flowing into the fuel inlet line 114. The oil inlet tube 114 is in fluid communication with the fuel pump 101 for delivering fuel into the fuel pump 101.

In order to enable smooth flow of fuel into the fuel pump 101, a fuel transfer pump 107 is disposed downstream of the fuel inlet port 112 to increase the flow rate and pressure of the fuel. Meanwhile, in order to avoid backflow of the fuel in the fuel inlet pipe 114, a check valve 105 is provided downstream of the fuel delivery pump 107. A duplex filter 108 is provided downstream of the check valve 105 to filter impurities in the fuel oil, improving the filtering accuracy. A temperature sensor 110 and a pressure sensor 111 may be disposed between the duplex filter 108 and the fuel pump 101, the pressure sensor 111 may be a low pressure fuel inlet pressure sensor, the temperature sensor 110 is configured to monitor a temperature of fuel discharged from the duplex filter 108, and the pressure sensor 111 is configured to monitor a pressure of fuel discharged from the duplex filter 108.

The fuel filtered by the dual filter 108 may enter the fuel pump 101 for supplying fuel, the fuel pump 101 may be a high pressure fuel pump, and the inlet pipe 114 may be in fluid communication with a plurality of fuel pumps 101 for increasing efficiency. The fuel system 100 may also include a plurality of high pressure fuel lines 106 and a plurality of fuel injectors 102, and each fuel pump 101 may be in fluid communication with one fuel injector 102 via one high pressure fuel line 106 for increased efficiency. For improved safety, an alarm sensor 103 is arranged downstream of the high pressure line 106 for monitoring the pressure of the fuel to avoid that the fuel pressure is too low.

When the fuel delivery valve of the fuel pump 101 is opened, the fuel in the fuel inlet pipe 114 is impacted or disturbed by the fuel from the fuel pump 101, so that the pressure of the fuel in the fuel inlet pipe 114 is increased, pressure waves are formed and spread in the direction of the fuel inlet interface 112 in the fuel inlet pipe 114 at the sound velocity, and the pressure waves are reflected to the fuel pump 101 after reaching the fuel inlet interface 112. Because the fuel system 100 is a high pressure system, the compressibility of the fuel and the phenomena of tubing expansion, friction, tubing cross-sectional area variation, and blank shots make the pressure fluctuations more complex and create reciprocating oscillatory pressure waves.

Accordingly, to reduce pressure pulsations in the oil inlet pipe 114, the present invention provides an accumulator 109 for the fuel system 100, the accumulator 109 being disposed upstream of the fuel pump 101. Preferably, the accumulator 109 can be arranged between the fuel pump 101 and the pressure sensor 111 to ensure that the pressures of the fuel feeding machine under all working conditions are consistent, so that the pressure fluctuation of the fuel transmitted by the fuel pump 101 can be effectively absorbed, the pressure fluctuation transmitted to the pressure sensor 111 can be effectively blocked, the test value fluctuation of the pressure sensor 111 is avoided to be severe, the pressure display of the pressure sensor 111 is stabilized, and the monitoring effect and the result judgment of the pressure sensor 111 are prevented from being influenced.

As shown in fig. 2, the accumulator 109 includes a body 120 and a diaphragm 130, and a cavity is provided inside the body 120. The body 120 may be configured as a substantially cylindrical structure, and the body 120 may include a first wall 121, a second wall 122, and an annular wall 123, and the first wall 121 and the second wall 122 may be oppositely disposed in an axial direction of the accumulator 109. The first wall 121 may be provided with a charging oil inlet 124, and the charging oil inlet 124 may be in fluid communication with the oil inlet pipe 114.

In order to facilitate the connection between the energy storage oil inlet 124 and the oil inlet pipe 114, the first wall 121 is further provided with a connecting portion 125, and the connecting portion 125 protrudes outward from the outer surface of the first wall 121. The interface portion 125 is for connection to a wall of the oil inlet pipe 114 and the interface portion 125 is in fluid communication with the oil inlet pipe 114. An oil passage 126 is provided in the interface portion 125, one end of the oil passage 126 is communicated with the oil inlet pipe 114, and the other end of the oil passage 126 is communicated with the energy storage oil inlet 124. Thus, the fuel in the fuel inlet pipe 114 can flow to the charge inlet 124 through the oil passage 126 in the interface 125. To ensure pressure equalization, the axis of the accumulator oil inlet 124 may coincide with the axis X1 of the accumulator 109 and the axis of the oil passage 126 may coincide with the axis X1 of the accumulator 109.

The annular wall 123 is located between the first wall 121 and the second wall 122 in the axial direction of the accumulator 109, and opposite sides of the annular wall 123 in the axial direction of the accumulator 109 are connected to the first wall 121 and the second wall 122, respectively. The annular wall 123 is disposed around the circumferential direction of the body 120. Preferably, the first wall 121, the second wall 122 and the annular wall 123 may be integrally formed to ensure sealability.

The diaphragm 130 is disposed inside the body 120, and the diaphragm 130 may be disposed around the circumferential direction of the body 120 and connected to the annular wall 123. The diaphragm 130 may divide the cavity into the oil chamber 141 and the gas chamber 142 in the axial direction of the body 120, and the oil chamber 141 and the gas chamber 142 are not communicated. The oil chamber 141 is in fluid communication with the accumulator oil inlet 124, and fuel oil can enter the oil chamber 141 through the accumulator oil inlet 124, such that the oil chamber 141 is filled with fuel oil. The gas chamber 142 is filled with a gas, and the second wall 122 is provided with a gas inlet through which the gas can enter the gas chamber 142, preferably, the gas can be an inert gas with a certain pressure, such as nitrogen with a certain pressure, so that the gas chamber 142 is filled with nitrogen with a certain pressure, thereby ensuring safety.

The diaphragm 130, the first wall 121, and a portion of the annular wall 123 may form an oil chamber 141, and the oil chamber 141 may be in communication with the charge oil inlet 124. In this way, fuel can flow into the oil chamber 141 via the accumulator inlet 124. The cross-sectional shape of the first wall 121 in a plane parallel to the axis X1 of the accumulator 109 may be substantially circular arc, so that it is ensured that fuel does not remain in the oil chamber 141 when the fuel is discharged from the oil chamber 141.

The diaphragm 130, the second wall 122 and the further part of the circumferential wall 123 may form a gas chamber 142, and in order to avoid gas leakage, the gas inlet may be sealed by a closure member 127. Closure member 127 may be a socket head cap screw. The cross-sectional shape of the second wall 122 in a plane parallel to the axis X1 of the accumulator 109 may be substantially trapezoidal, thereby facilitating the installation and sealing of the closure member 127. The annular wall 123 is formed with a step 128 protruding inward in the radial direction of the accumulator, preferably, the diaphragm 130 is located between the step 128 and the accumulator oil inlet 124, and the step 128 may be located in the air chamber 142, so that the structural strength of the annular wall 123 is improved.

The diaphragm 130 is configured to be deformable. When the pressure of the fuel in the fuel inlet pipe 114 becomes high, the fuel in the fuel inlet pipe 114 can enter the body 120 through the accumulator inlet 124. Specifically, when the pressure of the fuel is greater than the pressure of the gas, the gas is compressed, the diaphragm 130 moves toward the second wall 122, the volume of the oil chamber is thereby changed, and the fuel is drawn into the accumulator 109, eventually regulating the pressure of the fuel. When the pressure of the fuel is less than the pressure of the gas, the gas expands, the diaphragm 130 moves toward the first wall 121, and the volume of the oil chamber is thus changed, thereby pressing the fuel back into the oil feed pipe 114, and finally regulating the pressure of the fuel.

Further, the diaphragm 130 may be made of a flexible material, thereby facilitating deformation. The material of the diaphragm 130 may be the same as that of the body 120, thereby facilitating processing.

The diaphragm 130 may include a first surface and a second surface opposite the first surface, the first surface may face the first wall 121, and the second surface may face the second wall 122. The first surface may be connected to the inner surface of the annular wall 123 in the oil chamber 141 to ensure sealability. The second surface may be connected to the inner surface of the annular wall 123 located in the gas chamber 142, and the inner surface of the annular wall 123 located in the gas chamber 142 may be smoothly transitioned to the second surface. Thus, the inner surface of the annular wall 123 at the gas chamber 142 may be closer to the axis X1 of the accumulator 109 than the inner surface of the annular wall 123 at the oil chamber 141.

The height difference between the inner surface of the annular wall 123 located at the gas chamber 142 and the inner surface of the annular wall 123 located at the oil chamber 141 may be the thickness of the diaphragm 130, i.e., the height difference between the inner surface of the annular wall 123 located at the gas chamber 142 and the inner surface of the annular wall 123 located at the oil chamber 141 may be the distance between the first surface and the second surface.

When the pressure of the fuel in the fuel inlet pipe 114 is reduced, the pressure of the gas in the gas chamber 142 is greater than the pressure of the fuel in the oil chamber 141, and the diaphragm 130 may be moved toward the charge inlet port 124, so that the fuel in the oil chamber 141 is discharged into the fuel inlet pipe 114.

When the fuel is completely discharged from the oil chamber 141, the diaphragm 130 may be closely fitted to the second wall 122 and a portion of the annular wall 123 such that the volume of the oil chamber 141 is approximately equal to zero and the volume of the gas chamber 142 is approximately equal to the volume of the cavity, thereby compensating for the fuel in the fuel inlet pipe 114.

Further, the diaphragm 130 is provided with a blocking portion 131, and the blocking portion 131 may be disposed at a position opposite to the charge oil inlet 124. Preferably, the blocking portion 131 may protrude from the second surface toward the second wall 122, thereby improving the structural strength of the blocking portion 131. During the manufacturing process, the blocking portion 131 may be formed by pre-hardening the diaphragm 130 to ensure that the diaphragm 130 is integrally formed, thereby ensuring the sealing property of the diaphragm 130.

When the pressure of the gas in the gas chamber 142 is greater than the pressure of the fuel in the oil chamber 141, the blocking portion 131 moves in the direction of the charge oil inlet 124. When the accumulator 109 is completely emptied of fuel, the diaphragm 130 abuts the first wall 121 and the blocking portion 131 closes the accumulator inlet 124, thereby preventing the diaphragm 130 from being damaged.

According to the utility model discloses an energy storage ware 109, energy storage ware 109 include body 120 and diaphragm 130, and the inside of body 120 is provided with the cavity, and diaphragm 130 can separate the cavity for oil cavity 141 and gas cavity 142, and the fuel can be filled in oil cavity 141, and gas can be filled in gas cavity 142, and the diaphragm structure is the volume that can deform in order to change the oil cavity, utilizes gaseous compressibility to store the fuel. Therefore, when the pressure of the fuel in the fuel inlet pipe 114 changes, the pressure fluctuation of the fuel in the pipeline can be effectively absorbed, the pressure of the fuel inlet machine under the whole working condition can be ensured to be consistent, and the pressure fluctuation of the fuel transmitted by the fuel pump 101 can be effectively absorbed, so that the pressure fluctuation is effectively prevented, particularly the pressure fluctuation transmitted from the fuel pump 101 to the pressure sensor 111 is prevented, and the pressure display of the pressure sensor 111 is stabilized.

The utility model provides a fuel system 100, fuel system 100 can include foretell fuel pump 101, advance oil pipe 114 and accumulator 109. Thus, the accumulator 109 can effectively absorb the pressure fluctuation transmitted from the fuel pump 101, and can effectively adjust the pressure fluctuation transmitted to the pressure sensor 111, thereby stabilizing the pressure display of the pressure sensor 111.

Further, as shown in fig. 1, the fuel system 100 may further include a pressure regulator 104 and a fuel outlet pipe 115, the fuel pump 101 is provided with a fuel pump outlet, and the pressure regulator 104 is configured to connect the fuel pump outlet and the fuel outlet pipe 115 to balance the pressure of the fuel discharged from the fuel pump.

As shown in FIG. 3, the pressure regulator 104 may include a housing 150 and a piston 160, the housing 150 may have a generally L-shaped longitudinal cross-section, the housing 150 may have a pressure regulating inlet 151 and a pressure regulating outlet 152, and the pressure regulating inlet 151 may be in fluid communication with the fuel pump outlet so that fuel discharged from the fuel pump 101 may flow through the fuel pump outlet to the pressure regulating inlet 151.

The housing 150 further includes a first cavity 153, a second cavity 154, and a third cavity 155, the first cavity 153 and the third cavity 155 being located on opposite sides of the second cavity 154, respectively. The first cavity 153 is communicated with the pressure regulating oil inlet 151, and the axis of the first cavity 153 coincides with the axis of the pressure regulating oil inlet 151. The first cavity 153 may include a first sub-cavity 156 and a second sub-cavity along an axial direction of the first cavity 153. The axis of the first sub-chamber 156 coincides with the axis of the first chamber 153. The first sub-chamber 156 may be configured in a substantially cylindrical shape, and the first sub-chamber 156 is adapted to communicate with the pressure regulating oil inlet 151, thereby accommodating fuel discharged from the fuel pump 101.

The dimension of the second sub-chamber in the radial direction of the first chamber 153 is smaller than the dimension of the first sub-chamber 156. The second branch chamber may include three branch chambers 157, the three branch chambers 157 are arranged at intervals in the radial direction of the first chamber 153, and the three branch chambers 157 do not communicate with each other in the radial direction of the first chamber 153. The axes of the three diversion cavities 157 at the middle position are coincident with the axis of the first cavity 153, and the axes of the three diversion cavities 157 at the upper and lower positions are parallel to the axis of the first cavity 153. One ends of the three branch chambers 157 in the axial direction of the first chamber 153 are each in fluid communication with the first branch chamber 156. Thus, the fuel in the first branch chamber 156 enters the three branch chambers 157, respectively, thereby increasing the pressure of the fuel.

The axis of the first cavity 153 is perpendicular to the axis of the second cavity 154, and the first cavity 153 and the second cavity 154 may be vertically disposed therebetween. The second chamber 154 is in fluid communication with the pressure regulating outlet 152, and an axis of the second chamber 154 is parallel to an axis of the pressure regulating outlet 152. Thus, the axis of the pressure regulating oil inlet 151 is perpendicular to the axis of the pressure regulating oil outlet 152.

A first cavity 153 is disposed at one side of the second cavity 154, and a third cavity 155 is disposed at the other side of the second cavity 154 opposite to the first cavity 153. At least a portion of the piston 160 may be disposed in the third cavity 155, and the piston 160 may be movable relative to the housing 150 along an axial direction of the third cavity 155. The axis of the third cavity 155 may be parallel to the axis of the first cavity 153. Preferably, the axis of the piston 160 and the axis of the third cavity 155 may coincide with the axis of the first cavity 153, so as to ensure the coaxiality of the movement of the piston 160.

An end of the piston 160 facing the first chamber 153 (second sub-chamber) may be provided with first and second recesses 162, and the first recess may be provided at an outer circumferential surface of the piston 160 around a circumferential direction of the piston 160. The third cavity 155 may have a size in a radial direction of the first cavity 153 larger than that of the second sub-cavity, so that the first recess can close the second sub-cavity, thereby allowing the piston 160 to close the first cavity 153. When the end of the piston 160 closes the first cavity 153, a portion of the piston 160 is disposed in the third cavity 155 and another portion of the piston 160 is disposed in the second cavity 154.

The second recess 162 may be recessed from an end surface of the piston 160 facing the second sub-chamber in a direction away from the second sub-chamber, and the longitudinal sectional shape of the second recess 162 may be triangular. In this way, the fuel in the second branch chamber can flow into the second recess 162, and particularly the fuel in the branch chamber located at the middle position can flow into the second recess 162, so that the fuel in the three branch chambers 157 can be intensively applied to the end of the piston 160, so that the piston 160 can be moved in the axial direction of the third chamber 155. The size of the third chamber 155 in the axial direction of the first chamber 153 is larger than that of the piston 160 so that the piston 160 can move in the axial direction of the third chamber 155 relative to the housing 150 without falling.

The dimension of the piston 160 in the radial direction of the first cavity 153 may be approximately equal to the dimension of the third cavity 155, so that the piston 160 is caught in the third cavity 155, thereby ensuring that the piston 160 does not shift when moving relative to the third cavity 155 in the axial direction of the third cavity 155.

When the pressure of the fuel is sufficient to push the piston 160 to move away from the pressure regulating oil inlet 151, the piston 160 can move away from the pressure regulating oil inlet 151 to a predetermined position, and the first cavity 153 communicates with the second cavity 154. In the present embodiment, the "predetermined position" does not refer to a certain fixed position, but refers to a position at which the piston can move to communicate the first chamber with the second chamber. Thus, the fuel flowing in from the pressure regulating oil inlet 151 can flow to the pressure regulating oil outlet 152 via the first cavity 153 and the second cavity 154 which are perpendicular to each other. When the pressure of the fuel is sufficiently great, the entire piston 160 can be disposed in the third cavity 155.

To enhance stability of the fuel flow, the second cavity 154 may include a large diameter portion having a diameter greater than that of the small diameter portion and a small diameter portion communicating with the large diameter portion. Another portion of the piston 160 may be disposed in the small diameter portion. When the piston 160 moves in a direction away from the pressure regulating oil inlet 151, the small diameter portion may communicate with the first cavity 153, and the large diameter portion is for communicating with the pressure regulating oil outlet 152. Thus, the fuel can flow into the large diameter portion through the small diameter portion, thereby ensuring stable flow of the fuel and preventing a large amount of fuel from flowing directly to the pressure regulating oil outlet 152.

Further, to ensure that the fuel pressure in fuel system 100 is at a stable value, pressure regulator 104 also includes a spring 171. A cover 170 is disposed on a side of the housing 150 opposite to the pressure regulating oil inlet 151, and the cover 170 may enclose the third cavity 155.

The piston 160 is provided with a first groove 161, and the opening of the first groove 161 faces the cover 170. A spring 171 is provided between the first recess 161 and the cover 170, one end of the spring 171 abuts against the cover 170, and the other end of the spring 171 abuts against the first recess 161. Thus, the fuel pump operates by balancing the spring force of the spring 171 and the force generated by the pressure of the fuel in the pressure regulating inlet 151. The fuel inlet pressure p of the regulator 104 is substantially constant corresponding to a certain pre-compression amount Xo of the spring 171. If the fuel pressure of the fuel system 100 increases, the piston 160 moves away from the pressure regulating inlet 151, the distance between the piston 160 and the pressure regulating inlet 151 increases, and the flooding resistance decreases, so that the fuel pressure of the fuel system 100 decreases. When the pressure of the pressure regulating oil inlet 151 is lower than the set pressure, the piston 160 moves towards the direction of the pressure regulating oil inlet 151, the distance between the piston 160 and the pressure regulating oil inlet 151 is reduced, the overflow resistance is increased, the fuel pressure of the fuel system 100 is limited from continuously decreasing, and therefore the pressure stability of the hydraulic system is maintained.

In the initial state of the pressure regulator 104, the piston 160 closes the first cavity 153, the first cavity 153 is not communicated with the second cavity 154, and the fuel in the pressure regulating oil inlet 151 and the pressure regulating oil outlet 152 is isolated. Fuel discharged from the fuel pump 101 enters the first cavity 153 via the pressure regulating oil inlet 151, and the fuel in the first cavity 153 can act on an end of the piston 160. When the hydraulic pressure of the fuel is equal to or greater than the elastic force of the spring 171, the piston 160 moves to a predetermined position in a direction away from the pressure regulating oil inlet 151, so that the first cavity 153 and the second cavity 154 are communicated, which is equivalent to opening the opening of the pressure regulator 104, until the piston 160 is balanced in force, and the fuel pressure reaches a preset pressure.

Further, in order to adjust the elastic force of the spring 171, an adjustment screw 172 is provided on the cover 170, and the adjustment screw 172 is coupled to the cover 170 by an adjustment nut 173. The adjustment screw 172 is movable relative to the cover 170 in the axial direction of the third cavity 155. The cover 170 is further provided with a second groove 175, and the opening of the second groove 175 faces the direction of the piston 160. The inner end of the adjustment screw 172 in the housing 150 is disposed in the second recess 175, and the inner end of the adjustment screw 172 abuts against one end of the spring 171. In this way, the adjustment screw 172 moves in the axial direction of the third chamber 155 relative to the cover 170, thereby adjusting the pre-compression amount Xo of the spring 171, thereby flexibly adjusting the elastic force applied by the spring 171 to the piston 160, and thus adjusting the overflow resistance.

In order to enhance the firm connection between the spring 171 and the cover 170, the inner end of the adjusting screw 172 is further provided with a latching portion 174, and one end of the spring 171 can be wound around the latching portion 174, thereby preventing the spring 171 from falling off. The cover 170 may also be coupled to an outer cover that may be snapped onto the cover to cover the outer end of the adjustment screw 172 that is located on the cover 170, thereby protecting the adjustment screw 172.

According to the utility model discloses a pressure regulator, the produced effort of the elastic force of spring 171 and the oily pressure of pressure regulating oil inlet 151 are balanced mutually, and the pressure regulator can be adjusted the oily pressure value of fuel pump 101 exhaust for appointed value to restriction fuel oil system 100 pressure.

Returning now to fig. 1, a check valve 105 is disposed downstream of the pressure regulator 104, the check valve 105 being in fluid communication with the fuel outlet port 113. The fuel discharged from the fuel pump 101 flows to the fuel outlet port 113 through the pressure regulator 104 and the check valve 105. In the fuel system 100, the pressure of fuel entering the fuel pump 101 may be monitored by a pressure sensor 111, and the pressure of fuel discharged from the fuel pump 101 may be established and regulated by a pressure regulating valve.

According to the utility model discloses a fuel oil system can be applied to the marine medium speed diesel engine of 6CS21, for example can be the low pressure fuel oil system of marine medium speed diesel engine.

The fuel oil system comprises the energy accumulator, the energy accumulator can be located between the pressure sensor and the fuel pump, so that the low pressure when fuel oil enters the fuel pump under the low working condition is avoided, the high pressure when the fuel oil enters the fuel pump under the high working condition is also avoided, the pressure of the fuel oil can be ensured to be 5-6bar under each working condition, the problem of severe test fluctuation of the pressure sensor can be avoided, the fluctuation amplitude is reduced to 0.5bar, the pressure value of the pressure sensor is stably displayed, and the monitoring effect is greatly improved.

The fuel system also comprises a pressure regulator, wherein the pressure regulator can balance the pressure of the fuel discharged from the fuel pump, balance the pressure of the fuel to a set value, ensure that the pressure values of the fuel in the fuel system under different flows are kept consistent, and meet the design requirements of the system.

In the test, the marine medium-speed diesel engine is loaded to 100% working condition according to the propelling working condition, then the adjusting nut of the pressure regulator adjusts the pretightening force of the spring until the fuel feeding pressure is 5.5bar, and then 100%, 75%, 50%, 25% propelling, 25% loading and the fuel feeding pressure and temperature under idle speed are recorded according to the working condition change in sequence. Table 1 is the test data during the test.

TABLE 1 the utility model discloses experimental verification data

Referring to the above test data, the fuel pressure fluctuation of the fuel system was improved with the amplitude controlled at 0.5 bar. The consistency of the pressure level of the feeding machine under various working conditions is improved, the whole working condition is controlled to be 5.3-5.8 bar, and the idle speed is controlled to be 3.3 ba.

Unless defined otherwise, technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Terms such as "disposed" and the like, as used herein, may refer to one element being directly attached to another element or one element being attached to another element through intervening elements. Features described herein in one embodiment may be applied to another embodiment, either alone or in combination with other features, unless the feature is otherwise inapplicable or otherwise stated in the other embodiment.

The present invention has been described in terms of the above embodiments, but it is to be understood that the above embodiments are for purposes of illustration and description only and are not intended to limit the invention to the described embodiments. It will be appreciated by those skilled in the art that many more modifications and variations are possible in light of the above teaching and are intended to be included within the scope of the invention.

Claims

1. An accumulator for use in a fuel system including a fuel pump and an inlet tube in fluid communication with the fuel pump for delivering fuel into the fuel pump, the accumulator being disposed upstream of the fuel pump, the accumulator comprising:

the body, the inside of body is provided with the cavity, the body includes:

2. The accumulator according to claim 1, characterized in that the diaphragm is provided with a blocking portion which is arranged opposite the accumulator oil inlet and which moves in the direction of the accumulator oil inlet when the pressure of the gas in the gas chamber is greater than the pressure of the fuel oil in the oil chamber.

3. The accumulator according to claim 2, characterized in that the blocking portion closes the accumulator oil inlet when the diaphragm abuts against the first wall.

4. An accumulator according to claim 1, characterized in that the second wall is provided with an air inlet and a closure for sealing the air inlet.

5. The accumulator according to claim 1, characterized in that the annular wall is formed with a step projecting radially inwardly of the accumulator, the diaphragm being located between the step and the accumulator oil inlet.

6. A fuel system comprising a fuel pump, an oil inlet pipe and an accumulator according to any one of claims 1-5.

7. The fuel system as recited in claim 6, further comprising a pressure regulator and a fuel line, said fuel pump having a fuel pump outlet, said pressure regulator for connecting said fuel pump outlet to said fuel line.

8. The fuel system as recited in claim 7, wherein said pressure regulator comprises:

the first cavity is communicated with the pressure regulating oil inlet;

9. The fuel system of claim 8, wherein a cover is disposed on a side of the housing opposite to the pressure regulating oil inlet, a groove is disposed on the piston, an opening of the groove faces the cover, a spring is disposed between the groove and the cover, one end of the spring abuts against the cover, and the other end of the spring abuts against the groove.

10. The fuel system as recited in claim 9, wherein an adjustment screw is provided on the cover, the adjustment screw being movable relative to the cover in an axial direction of the third cavity, an inner end of the adjustment screw located in the housing abutting the one end of the spring.