EMULSION PISTON PUMP AND PUMP HEAD ASSEMBLY FOR IT

Description

FIELD

[0001] The present invention relates to a field of design and manufacture of emulsion pumps, and more particularly to an emulsion plunger pump and a pump head assembly thereof.BACKGROUND

[0002] In recent years, with more and more working faces with large mining height in China, in order to meet the requirements of high support resistance and high working resistance of hydraulic supports with large mining height, as well as rapid support moving and safety support, higher demands in terms of the reliability of emulsion pump stations have been put forward. An emulsion pump provides hydraulic power for the hydraulic support of the working face, and is the heart of the hydraulic system for the whole working face. An emulsion plunger pump is a device that uses emulsion or water as a medium, does work on the emulsion through an internal structure of a crankcase, and then converts it into hydraulic energy of the emulsion.

[0003] A pump head assembly of the emulsion pump has a chamber structure, and a liquid suction valve component, a liquid discharge valve component and a spacer sleeve are arranged in the chamber. In an existing plunger pump, a reset spring mounting seat of a liquid suction valve core is designed at a lower part of a liquid discharge valve core. On the one hand, the mass of the liquid discharge valve core is increased, causing large inertia force; on the other hand, a high-pressure liquid flow has impact on the liquid suction valve core and the liquid discharge valve core, resulting in a large force on a single side, and eccentric wear of a guide portion and hence of a sealing ring surface when the valve core rises or falls, which affects the service life. Additionally, in the existing plunger pump, the liquid suction valve core component and the liquid discharge valve component in the pump head body are assembled from both sides of a pump head body. Consequently, during replacement of a liquid suction valve seat, the liquid suction valve core, a liquid discharge valve seat and the liquid discharge valve core, it is necessary to remove parts such as a liquid suction pipeline and a water suction box, which causes poor operability, long maintenance time and high maintenance cost.

[0004] CN 111734621 A discloses a pump head assembly for an emulsion plunger pump. The pump head assembly includes a pump head body having a hollow chamber extending in a first direction, a liquid suction valve assembly and a liquid discharge valve assembly sequentially arranged within the hollow chamber along the first direction. The liquid suction valve assembly includes a liquid suction valve seat and a liquid suction valve core, and the liquid discharge valve assembly includes a liquid discharge valve seat and a liquid discharge valve core. The hollow chamber defines two liquid discharge ports on a liquid discharge side of the liquid discharge valve assembly, the two liquid discharge ports respectively extend in a second direction to form a liquid discharge channel of the pump head assembly, and the first direction is perpendicular to the second direction. The two liquid discharge ports are symmetrically arranged on both sides of an axial direction of the liquid discharge valve core, and in a radial direction of the liquid discharge valve core, there a gap between a liquid discharge cross-section of the liquid discharge port and the liquid discharge valve core. The present disclosure solves the problem that the liquid discharge valve core of the existing emulsion plunger pump is susceptible to hydraulic impact. The present disclosure further discloses a plunger pump employing the aforementioned pump head assembly.

[0005] CN 111608903 A discloses a liquid suction and discharge valve and a working method thereof, belonging to the technical field of coal mining. In the present disclosure, a liquid suction valve and a liquid discharge valve are linearly arranged, resulting in a more compact structure; a structure of a guide is simple, leading to reduced friction; a valve seat may be used on both sides, thereby extending its service life; the valve seat is in clearance fit with a mounting hole, thus facilitating easy replacement; a medium flow rate design reduces cavitation; and the liquid suction valve and the liquid discharge valve may be used interchangeably, thus achieving fewer spare parts.SUMMARY

[0006] The first technical problem to be solved by the present invention is related to the eccentric wear of the valve core and short service life due to the unreasonable internal structure of the pump head assembly of the existing plunger pump.

[0007] The present invention provides the following technical solutions directed at the above technical problem.

[0008] The present invention is defined in independent claims, and the preferable features according to the present invention are defined in the dependent claims. Any detail in the present disclosure that does not fall within the scope of the present invention as defined by the appended claims should be regarded as an example for understanding the present invention.

[0009] A pump head assembly of an emulsion plunger pump includes: a pump head body having a hollow chamber; a liquid suction valve component; a liquid discharge valve component; a spacer sleeve component; and an end cover detachably connected to an end of the pump head body and configured to close the hollow chamber. The liquid suction valve component, the spacer sleeve component and the liquid discharge valve component are sequentially mounted in the hollow chamber. The liquid suction valve component includes a liquid suction valve seat, a liquid suction valve core and a first reset spring, the liquid suction valve core being slidably connected to the spacer sleeve component, and the first reset spring being between the spacer sleeve component and the liquid suction valve core.

[0010] The spacer sleeve component includes a spacer sleeve body and a sliding sleeve fixedly connected to the spacer sleeve body; and the liquid suction valve core is slidably connected to the sliding sleeve.

[0011] In some embodiments of the present invention, an outer wall of the spacer sleeve body includes an anti-rotation groove; the pump head body includes a first connection hole extending in a radial direction; and the spacer sleeve body is positioned by a positioning member inserted into the anti-rotation groove through the first connection hole.

[0012] The spacer sleeve body includes: an outer sleeve in clearance fit with an inner wall of the hollow chamber; an inner sleeve in interference fit with the sliding sleeve; and a transition connection portion configured to connect the outer sleeve and the inner sleeve.

[0013] The liquid suction valve seat is formed as a plate body with a liquid suction through hole in the center; an annular groove is formed on one side of the plate body; and the outer sleeve of the space sleeve body is inserted into the annular groove.

[0014] In some embodiments of the present invention, the liquid suction valve core includes: a valve core plug formed as a flat body larger than the liquid suction through hole; and a valve core sliding portion formed as a sliding rod extending along an axial direction of the hollow chamber.

[0015] In some embodiments of the present invention, the liquid discharge valve component includes: a liquid discharge valve seat including a liquid discharge through hole having a first conical surface; a liquid discharge valve core slidably connected to the liquid discharge through hole of the liquid discharge valve seat, and including a second conical surface fitted with the first conical surface; a liquid discharge valve core check valve between the liquid discharge valve core and the end cover; and a second reset spring having a first end fitted over the liquid discharge valve core and a second end abutting against the liquid discharge valve core check valve.

[0016] In some embodiments of the present invention, a positioning structure is arranged between the spacer sleeve body and the liquid discharge valve seat. The positioning structure includes: a positioning protrusion or a positioning groove arranged on the spacer sleeve body; and a positioning groove or a positioning protrusion correspondingly arranged on the liquid discharge valve seat.

[0017] In some embodiments of the present invention, an inner wall of the hollow chamber includes a first step, and the first step divides the hollow chamber into a first chamber and a second chamber; an inner diameter of the first chamber is larger than an inner diameter of the second chamber; and the liquid suction valve component, the spacer sleeve component and the liquid discharge valve component are mounted in the first chamber.

[0018] The present invention also discloses an emulsion plunger pump that includes the above pump head assembly for pumping emulsion; a crankcase assembly connected to a main drive motor; and a hydraulic conversion assembly having a first end connected to the crankcase assembly and a second end connected to the pump head assembly.

[0019] In some embodiments of the present invention, a gap with a predetermined distance exists between the crankcase assembly and the pump head assembly.

[0020] Compared with the related art, the technical solutions of the present invention has the following technical effects.

[0021] In the pump head assembly of the emulsion plunger pump according to the present invention, the liquid suction valve component and the liquid discharge valve component are separated by the spacer sleeve component; the liquid suction valve core is slidably connected to the spacer sleeve component; and the first reset spring is between the spacer sleeve component and the liquid suction valve core, so that the liquid suction valve core is not affected by the action of the liquid discharge valve core when being reset, and the liquid suction valve core is reliably closed. At the same time, since the liquid suction valve core is slidably connected to the spacer sleeve component and is arranged on a side of the liquid suction valve seat away from a liquid suction box component, the liquid suction valve core is less impacted during liquid suction and has a longer service life.

[0022] Further, in the pump head assembly of the emulsion plunger pump according to the present invention, the liquid suction valve seat and the liquid suction valve core of the liquid suction valve component adopts the planar fit, and the liquid discharge valve core and the liquid discharge valve seat of the liquid discharge valve component 103 adopts the conical surface fit, which can make the service life of the liquid discharge valve component equal to the service life of the liquid suction valve component, and can maintain and replace the liquid discharge valve component and the liquid suction valve component at the same time, avoiding the waste of components caused by different use conditions of various components when being replaced, due to a large difference in the service life of the components.

[0023] Further, in the pump head assembly of the emulsion plunger pump according to the present invention, the inner wall of the hollow chamber includes the first step that divides the hollow chamber into the first chamber and the second chamber; the inner diameter of the first chamber is greater than that of the second chamber; the liquid suction valve component, the spacer sleeve and the liquid discharge valve component are mounted in the first chamber; and the second chamber is configured for connection with the liquid suction box component. In this way, the liquid discharge valve component, the spacer sleeve component and the liquid suction valve component are all mounted from a liquid discharge side of the hollow chamber. During maintenance, the pump head body can be repaired without removing oil supply pipelines.BRIEF DESCRIPTION OF DRAWINGS

[0024] Embodiments of the present invention will be described below in detail with reference to the accompanying drawings, which will help to understand the objectives and advantages of the present invention, wherein: FIG. 1 is a schematic view of a pump head assembly of an emulsion plunger pump according to an embodiment of the present invention; FIG. 2 is a schematic view of a liquid suction valve seat according to an embodiment of the present invention; FIG. 3 is a schematic view of a liquid suction valve core according to an embodiment of the present invention; FIG. 4 is a schematic view of a liquid discharge valve seat according to an embodiment of the present invention; FIG. 5 is another schematic view of a liquid discharge valve seat according to an embodiment of the present invention; FIG. 6 is a schematic view of a liquid discharge valve core according to an embodiment of the present invention; FIG. 7 is a schematic view of a spacer sleeve component according to an embodiment of the present invention; FIG. 8 is a schematic view of a pump head body according to an embodiment of the present invention. DETAILED DESCRIPTION

[0025] In the description of the present invention, it should be appreciated that terms such as "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner" and "outer" are construed to refer to the orientation or positions as then described or as shown in the drawings under discussion. These terms are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation and be constructed or operated in a particular orientation. Thus, these terms shall not be construed as limitation on the present invention. In addition, terms such as "first," "second" and "third" are only used for purposes of description and cannot be understood as indicating or implying relative importance.

[0026] In the description of the present invention, it should be noted that unless specified or limited otherwise, terms "mounted," "connected," and "coupled" should be understood broadly, and may be, for example, fixed connection, detachable connection or integrated connection; may also be direct connections or indirect connections via intervening structures; and may also be inner connection of two elements. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0027] In addition, technical features involved in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0028] FIG. 1 illustrates a specific embodiment of a pump head assembly of an emulsion plunger pump according to the present invention. The pump head assembly 100 includes a pump head body 101 with a hollow chamber 101a, a liquid suction valve component 102, a spacer sleeve component 104 and a liquid discharge valve component 103, all of which are mounted in the hollow chamber 101a in sequence from bottom to top. The pump head assembly 100 further includes an end cover 105 configured to seal the hollow chamber 101a and detachably connected to an upper end of the pump heat body 101.

[0029] The liquid suction valve component 102 includes a liquid suction valve seat 1021, a liquid suction valve core 1022 and a first reset spring 1023. The liquid suction valve core 1022 is slidably connected to the spacer sleeve component 104, and the first reset spring 1023 is between the spacer sleeve component 104 and the liquid suction valve core 1022.

[0030] In the above-mentioned pump head assembly 100, the liquid suction valve component 102 and the liquid discharge valve component 103 are separated by the spacer sleeve component 104; the liquid suction valve core 1022 is slidably connected to the spacer sleeve component 104; and the first reset spring 1023 is between the spacer sleeve component 104 and the liquid suction valve core 1022, so that the liquid suction valve core 1022 is not affected by the action of the liquid discharge valve core when being reset, and the liquid suction valve core 1022 is reliably closed. At the same time, since the liquid suction valve core 1022 is arranged on an upper side of the liquid suction valve seat 1021 and is slidably connected to the spacer sleeve component 104, the liquid suction valve core 1022 is less impacted during liquid suction and has a longer service life, compared with the liquid suction valve core 1022 being arranged on a lower side of the liquid suction valve seat 1021.

[0031] Specifically, as shown in FIG. 7, the spacer sleeve component 104 includes a spacer sleeve body 1041 and a sliding sleeve 1042 fixedly connected to the spacer sleeve body 1041, and the liquid suction valve core 1022 is slidably connected to the sliding sleeve 1042. More specifically, the sliding sleeve 1042 is made of a soft copper sleeve, and the sliding of the liquid suction valve core 1022 relative to the copper sleeve can reduce its own wear and prolong the service life of the liquid suction valve core 1022.

[0032] Specifically, as shown in FIG. 7, the spacer sleeve body 1041 includes an outer sleeve 1041a in clearance fit with an inner wall of the hollow chamber 101a, an inner sleeve 1041b in interference fit with the sliding sleeve 1042, and a transition connection portion 1041c configured to connect the outer sleeve 1041a and the inner sleeve 1041b. The outer sleeve 1041a is configured to isolate the liquid suction valve component 102 from the liquid discharge valve component 103, and the inner sleeve 1041b is configured to mount the sliding sleeve 1042 to achieve sliding fit with the liquid suction valve core 1022.

[0033] The spacer sleeve body 1041 adopts the structure of inner and outer sleeves, so that the liquid suction valve core 1022 can reliably slide along the inner sleeve 1041b of the spacer sleeve body 1041, and the radial shaking of the liquid suction valve core 1022 relative to the liquid suction valve seat 1021 in the related art can be avoided.

[0034] Specifically, the pump head body 101 includes a pump head connection hole for connection with a hydraulic conversion assembly 200; the spacer sleeve body 1041 includes a spacer sleeve connection hole corresponding to the pump head connection hole; and a part of the hydraulic conversion assembly 200 extends into the hollow chamber 101a along the pump head connection hole and the spacer sleeve connection hole. The hydraulic conversion assembly 200 is configured to convert mechanical power of a crankcase into hydraulic changes of the pump head assembly 100.

[0035] More specifically, the hydraulic conversion assembly 200 can extend into the hollow chamber 101a only when the spacer sleeve connection hole is opposite to the pump head connection hole. In order to prevent the spacer sleeve body 1041 from rotating along an axial direction of the hollow chamber 101a, an outer wall of the spacer sleeve body 1041 includes an anti-rotation groove 1041d, the pump head body 101 includes a first connection hole extending in a radial direction, and the spacer sleeve body 1041 is positioned by a positioning member 106 inserted into the anti-rotation groove 1041d through the first connection hole.

[0036] In an embodiment, the positioning member 106 is a positioning pin, and since the hollow chamber 101a needs to be kept in a sealed state in a working state, a sealing member is arranged between the positioning member 106 and the pump head body 101 to ensure the sealing. In another embodiment, the positioning member 106 is a positioning screw, the first connection hole is a threaded hole, and the positioning screw is threadedly connected to the pump head body 101, with an end inserted into the anti-rotation groove 1041d to realize positioning; in order to achieve sealing, a sealing ring is arranged between a head of the positioning screw and the pump head body 101.

[0037] Specifically, as shown in FIG. 2, the liquid suction valve seat 1021 is formed as a plate body with a liquid suction through hole 1021a in the center; an annular groove 1021b is formed on one side of the plate body; and the outer sleeve 1041a of the spacer sleeve body 1041 is inserted into the annular groove 1021b. The positioning of the spacer sleeve body 1041 is more convenient due to the annular groove 1021b. More specifically, the liquid suction valve seat 1021 is sealed and connected to the pump head body 101 through a sealing ring 107.

[0038] As shown in FIG. 3, the liquid suction valve core 1022 includes a valve core plug 1022a configured to cooperate with the liquid suction through hole 1021a of the liquid suction valve seat 1021, and a valve core sliding portion 1022b configured to cooperate with the sliding sleeve 1042. The valve core plug 1022a is formed as a circular flat body larger than the liquid suction through hole 1021a, and the valve core sliding portion 1022b is formed as a sliding rod extending along the axial direction of the hollow chamber 101a. Under the action of hydraulic force, the valve core can slide axially in the sliding sleeve 1042 to open or block the liquid suction through hole 1021a of the liquid suction valve seat 1021.

[0039] Specifically, the liquid discharge valve component 103 includes a liquid discharge valve seat 1031, a liquid discharge valve core 1032, a liquid discharge valve core check valve 1034 and a second reset spring 1033. As shown in FIGS. 4 and 5, the liquid discharge valve seat 1031 includes a liquid discharge through hole 1031a, and the liquid discharge through hole 1031a includes a first conical surface a. As shown in FIG. 6, the liquid discharge valve core 1032 is slidably connected to the liquid discharge through hole 1031a of the liquid discharge valve seat 1031, and the liquid discharge valve core 1032 includes a second conical surface b fitted with the first conical surface a. The liquid discharge valve core check valve 1034 is arranged between the liquid discharge valve plug 1032 and the end cover 105. A first end of the second reset spring 1033 is fitted over the liquid discharge valve core 1032, and a second end of the second reset spring 1033 abuts against the liquid discharge valve core check valve 1034. More specifically, sealing connection between the liquid discharge valve seat 1031 and the pump head body 101, and sealing connection between the liquid discharge valve core check valve 1034 and the pump head body 101 are realized by the sealing rings 107.

[0040] Since the pressure of emulsion is relatively high when the liquid discharge valve component 103 performs discharge, the liquid discharge valve core 1032 and the liquid discharge valve seat 1031 are subjected to relatively large impact. The sealing performance between the liquid discharge valve core 1032 and the liquid discharge valve seat 1031 is better through the conical surface fit, and at the same time, self-compensation can be realized after wear, thus prolonging the service life. The pressure of emulsion is relatively low when the liquid suction valve component 102 performs suction. Consequently, in the present invention, in the liquid suction valve component 102, the liquid suction valve seat 1021 and the liquid suction valve core 1022 adopt a planar fit; in the liquid discharge valve component 103, the liquid discharge valve core 1032 and the liquid discharge valve seat 1031 adopt the conical surface fit, which can make the service life of the liquid discharge valve component 103 equal to the service life of the liquid suction valve component 102, and can maintain and replace the liquid discharge valve component and the liquid suction valve component at the same time, avoiding the waste of components caused by different use conditions of various components when being replaced, due to a large difference in the service life of the components.

[0041] In order to further improve the installation and positioning of the liquid discharge valve component 103, a positioning structure is arranged between the spacer sleeve body 1041 and the liquid discharge valve seat 1031. The positioning structure includes a positioning protrusion or a positioning groove arranged on the spacer sleeve body 1041; and a positioning groove or a positioning protrusion correspondingly arranged on the liquid discharge valve seat 1031. More specifically, as shown in FIG. 6, an inner wall of the outer sleeve 1041a of the spacer sleeve body 1041 includes a positioning groove 1041e, and the liquid discharge valve seat 1031 includes a positioning protrusion 1031b at a corresponding position. In order to further prevent the liquid discharge valve seat 1031 from rotating in the hollow chamber 101a, the positioning groove 1041e is integrally formed as a square groove, and the positioning protrusion 1031b of the liquid discharge valve seat 1031 is a square protrusion fitted with the square groove.

[0042] The liquid discharge valve component 103, the spacer sleeve component 104 and the liquid suction valve component 102 are all mounted from a liquid discharge side of the hollow chamber 101a, so that the pump head body 101 can be overhauled without disassembling oil supply pipelines. Consequently, as shown in FIG. 8, the inner wall of the hollow chamber 101a includes a first step that divides the hollow chamber 101a into a first chamber 101a1 and a second chamber 101a2; an inner diameter of the first chamber 101a1 is larger than an inner diameter of the second chamber 101a2; the liquid suction valve component 102, the spacer sleeve component 104 and the liquid discharge valve component 103 are mounted in the first chamber 101a1; and the second chamber 101a2 is in connection with a liquid suction box component 108.

[0043] More specifically, the first chamber 101a1 may be formed as a chamber with a constant inner diameter from top to bottom, or may be provided with a plurality of stepped mounting surfaces with different inner diameters. In the first chamber 101a1, an inner diameter C of a first portion for mounting the liquid suction valve component 102 is smaller than an inner diameter B of a second portion for mounting the spacer sleeve component 104; and the inner diameter B of the second portion for mounting the spacer sleeve component 104 is smaller than an inner diameter A of a third portion for mounting the liquid discharge valve component 103. The liquid suction valve component 102, the spacer sleeve component 104 and the liquid discharge valve component 103 can be assembled and disassembled through an opening at the upper end of the pump head body 101, which is convenient and quick.

[0044] The present invention also provides a specific embodiment of a plunger pump adopting the above-mentioned pump head assembly 100, and the plunger pump according to this embodiment is a five-plunger emulsion pump. The plunger pump includes three parts. The first part is a crankcase assembly 300 connected to a main drive motor to transmit power. The second part is the pump head assembly 100 for pumping emulsion. The third part is the hydraulic conversion assembly 200 for converting the mechanical power of the crankcase into hydraulic changes of the pump head assembly 100, in which a first end of the hydraulic conversion assembly 200 is connected to the crankcase assembly 300 and a second end thereof is connected to the pump head assembly 100.

[0045] There is a gap with a predetermined distance between the crankcase assembly 300 and the pump head assembly 100, and the hydraulic conversion assembly 200 can be disassembled or mounted from the gap between the crankcase assembly 300 and the pump head assembly 100.

[0046] During operation of the plunger pump, a rotary motion input by the main drive motor drives an input crankshaft connecting rod to rotate, which is converted into a reciprocating linear motion of a plunger in the hydraulic conversion assembly 200, so that a volume of a cavity in the pump head assembly 100 changes. When the plunger is at a farthest end, the volume of the cavity is increased to form a negative pressure, the liquid suction valve core 1022 is opened, and the liquid discharge valve core 1032 is closed, in which way a liquid suction process is completed. When the plunger moves to a nearest end, the volume of the cavity is reduced, compressing the sucked liquid and forming high-pressure liquid, the liquid suction valve core 1022 is closed, and the liquid discharge valve core 1032 is opened to discharge the high-pressure liquid, in which way a liquid discharge is completed. The conical surface sealing between the liquid discharge valve core 1032 and the liquid discharge valve seat 1031 of the pump head assembly 100 ensures the high volumetric efficiency of the five-plunger pump, thus meeting actual liquid supply requirements of the hydraulic system for the fully mechanized mining face with super high mining height.

Claims

1. A pump head assembly (100) for an emulsion plunger pump, comprising: a pump head body (101) having a hollow chamber (101a); a liquid suction valve component (102); a liquid discharge valve component (103); a spacer sleeve component (104); and an end cover (105) detachably connected to an end of the pump head body (101) and configured to close the hollow chamber (101a), wherein: the liquid suction valve component (102), the spacer sleeve component (104) and the liquid discharge valve component (103) are sequentially arranged in the hollow chamber (101a), and the liquid suction valve component (102) and the liquid discharge valve component (103) are separated by the spacer sleeve component (104); and the liquid suction valve component (102) comprises a liquid suction valve seat (1021), a liquid suction valve core (1022) and a first reset spring (1023), the liquid suction valve core (1022) being slidably connected to the spacer sleeve component (104), and the first reset spring (1023) being between the spacer sleeve component (104) and the liquid suction valve core (1022); characterized in that, the spacer sleeve component (104) comprises a spacer sleeve body (1041) and a sliding sleeve (1042) fixedly connected to the spacer sleeve body (1041); and the liquid suction valve core (1022) is slidably connected to the sliding sleeve (1042), wherein the spacer sleeve body (1041) comprises: an outer sleeve (1041a) in clearance fit with an inner wall of the hollow chamber (101a); an inner sleeve (1041b) in interference fit with the sliding sleeve (1042); and a transition connection portion (1041c) configured to connect the outer sleeve (1041a) and the inner sleeve (1041b); and wherein the liquid suction valve seat (1021) is formed as a plate body with a liquid suction through hole (1021a) in the center; an annular groove (1021b) is formed on one side of the plate body; and the outer sleeve (1041a) of the space sleeve body is inserted into the annular groove (1021b).

2. The pump head assembly (100) according to claim 1, wherein an outer wall of the spacer sleeve body (1041) comprises an anti-rotation groove (1041d); the pump head body (101) comprises a first connection hole extending in a radial direction; and the spacer sleeve body (1041) is positioned by a positioning member (106) inserted into the anti-rotation groove (1041d) through the first connection hole.

3. The pump head assembly (100) according to claim 1, wherein the liquid suction valve core (1022) comprises: a valve core plug (1022a) formed as a flat body larger than the liquid suction through hole (1021a); and a valve core sliding portion (1022b) formed as a sliding rod extending along an axial direction of the hollow chamber (101a).

4. The pump head assembly (100) according to any one of claims 1-3, wherein the liquid discharge valve component (103) comprises: a liquid discharge valve seat (1031) comprising a liquid discharge through hole (1031a) having a first conical surface (a); a liquid discharge valve core (1032) slidably connected to the liquid discharge through hole (1031a) of the liquid discharge valve seat (1031), and comprising a second conical surface (b) fitted with the first conical surface (a); a liquid discharge valve core check valve (1034) between the liquid discharge valve core (1032) and the end cover (105); and a second reset spring (1033) having a first end fitted over the liquid discharge valve core (1032) and a second end abutting against the liquid discharge valve core check valve (1034).

5. The pump head assembly (100) according to claim 4, wherein: a positioning structure is arranged between the spacer sleeve body (1041) and the liquid discharge valve seat (1031); and the positioning structure comprises: a positioning protrusion or a positioning groove arranged on the spacer sleeve body (1041); and a positioning groove or a positioning protrusion correspondingly arranged on the liquid discharge valve seat (1031).

6. The pump head assembly (100) according to claim 1, wherein: an inner wall of the hollow chamber (101a) comprises a first step, and the first step divides the hollow chamber (101a) into a first chamber (101a1) and a second chamber (101a2); an inner diameter of the first chamber (101a1) is larger than an inner diameter of the second chamber (101a2); and the liquid suction valve component (102), the spacer sleeve component (104) and the liquid discharge valve component (103) are mounted in the first chamber (101a1).

7. An emulsion plunger pump comprising: a crankcase assembly (300) connected to a main drive motor; a pump head assembly (100) for pumping emulsion; and a hydraulic conversion assembly (200) having a first end connected to the crankcase assembly and a second end connected to the pump head assembly (100), wherein the pump head assembly is the pump head assembly according to any one of claims 1-6.

8. The emulsion plunger pump according to claim 7, wherein a gap with a predetermined distance exists between the crankcase assembly (300) and the pump head assembly (100).