High-pressure plunger pump

Abstract

A high-pressure plunger pump (1) comprises a pump head (2), a plunger housing (3) attached to the pump head (2), a valve body (5) arranged in respective receptacles of the pump head (2) and the plunger housing (3), at least one plunger assembly (4) arranged in the plunger housing (3) with a working chamber (41) and an axially movable plunger (42) delimiting the working chamber (41), at least one inlet valve (6) attached to or in the valve body (5) with an inlet (61) that can be closed by a closing element, at least one outlet valve (7) attached to or in the valve body (5) with an outlet (71) that can be closed by a closing element, wherein the inlet (61) is connected to a supply line (11), wherein the plunger housing (3) with the plunger assembly (4) arranged therein is surrounded by a chamber wall (8), and the pump head (2) has a cap (9) is installed, through which the supply line (11) is passed,wherein the cap (9) together with the chamber wall (8) fluid-tightly enclose the pump head (2) and the plunger housing (3).

Description

[0001] The present invention relates to a high-pressure plunger pump according to the preamble of claim 1.

[0002] High-pressure plunger pumps are used in a wide variety of applications. These pumps are particularly characterized by their robustness. One application is in marine propulsion systems, where they serve as injection pumps for internal combustion engines. Especially when using alternative fuels such as methanol or ammonia, stringent safety requirements must be met, particularly regarding potential fuel leaks.

[0003] The object of the present invention is to further develop a high-pressure plunger pump of the generic type in such a way as to meet particularly high safety requirements.

[0004] This problem is solved by a high-pressure plunger pump with the features of claim 1.

[0005] The high-pressure plunger pump according to the invention has a pump head, a plunger housing attached to the pump head and a plunger arrangement arranged in the plunger housing with at least one working chamber and at least one plunger arranged axially movable and defining the working chamber.

[0006] The high-pressure plunger pump also has a number of valve bodies, each with an inlet valve and an outlet valve, arranged in respective receptacles of the pump head and the plunger housing, corresponding to the number of plungers.

[0007] Furthermore, the high-pressure plunger pump has a suction port for connecting a supply line and a pressure port for connecting a high-pressure outlet.

[0008] The plunger housing with the plunger assembly arranged within it is surrounded by a chamber wall.

[0009] Furthermore, a cap with a suction port and a pressure port is attached to the pump head.

[0010] With the supply line and high-pressure outlet connected, the cap and the chamber wall enclose the pump head and the plunger housing in a fluid-tight manner.

[0011] A high-pressure plunger pump designed in this way is characterized by its high level of protection against fuel leakage.

[0012] The chamber wall and the cap provide double-walled protection against the escape of fuel pressurized in the high-pressure plunger pump.

[0013] A high-pressure plunger pump designed in this way is therefore suitable, among other things, for use as a fuel injection pump.

[0014] Advantageous embodiments of the invention are the subject of the dependent claims.

[0015] According to an advantageous embodiment, an adapter is inserted between the cap and the chamber wall, so that the cap and the adapter on the one hand and the chamber wall and the adapter on the other hand are mounted together in a fluid-tight manner.

[0016] The adapter enables an easy enclosure of the pump head and the plunger housing with the plunger assembly.

[0017] According to an advantageous embodiment, the cap and the chamber wall are designed as a single, one-piece component.

[0018] In an alternative design variant, the cap and the chamber wall are designed as separate components.

[0019] According to another advantageous embodiment, a cavity is formed between the cap and the pump head on the one hand, and between the chamber wall and the plunger housing on the other.

[0020] In this way, potential leaks can be inertized through the respective cavity and specifically diverted.

[0021] According to an advantageous embodiment, a seal between the plunger housing and the plunger is formed by at least one low-pressure seal and / or a barrier medium.

[0022] Particularly preferred is the sealing of the plunger housing to the plunger formed by two low-pressure seals and the barrier medium, wherein the barrier medium is provided between the two low-pressure seals.

[0023] The barrier medium makes it possible to completely seal off any potential fuel leaks. It is also conceivable to use the barrier medium to absorb and drain fuel leaks.

[0024] The sealing medium can preferably be supplied to the low-pressure seal via a supply channel provided in a sealing housing and discharged away from the low-pressure seal via a discharge channel provided in the sealing housing.

[0025] The low-pressure seal is preferably designed as a packing seal.

[0026] According to a first advantageous design variant, the suction connection is provided at the pump head.

[0027] In an alternative embodiment, the suction port is provided on the chamber wall, with the cap fluid-tightly enclosing the chamber wall and the pump head, and a cavity between the cap and the pump head extending into an area between the cap and the chamber wall.

[0028] This allows any potential leaks to be returned via the cavity between the chamber wall and the plunger housing to the valve receiving chamber while maintaining a double-walled protection against the escape of fuel brought to high pressure in the high-pressure plunger pump.

[0029] Preferred embodiments are explained in more detail below with reference to the accompanying drawing. It shows: Fig. 1 a schematic isometric representation of a first embodiment of a high-pressure plunger pump according to the invention, Fig. 2 a schematic first sectional view through the high-pressure plunger pump according to Fig. 1 showing several plungers arranged side by side and a high-pressure outlet, Fig. 3 a schematic second sectional view through the high-pressure plunger pump according to Fig. 1 perpendicular to the first section showing a plunger and a suction port, Fig. 4 a close-up of a section in Fig. 3 area marked IV of a low-pressure seal sealing the plunger, Fig. 5 a schematic isometric representation of a second embodiment of the high-pressure plunger pump according to the invention, and Fig. 6 a schematic sectional view through the high-pressure plunger pump according to Fig. 5 analogous to Fig. 3.

[0030] In the following figure descriptions, terms such as top, bottom, left, right, front, back, etc., refer exclusively to the exemplary representation and position of the high-pressure plunger pump, pump head, plunger assembly, plunger housing, cap, chamber wall, and the like as chosen in the respective figures. These terms are not to be understood as restrictive; that is, these references may change due to different operating positions, mirror-symmetrical design, or similar factors.

[0031] In the Fig. 1 to 3, 5 and 6 are collectively designated by reference numeral 1 as an embodiment of a high-pressure plunger pump according to the invention.

[0032] The high-pressure plunger pump 1 has a pump head 2 and a plunger housing 3 attached to the pump head 2.

[0033] A plunger arrangement 4 is arranged in the plunger housing 3, with at least one working chamber 41 and at least one plunger 42 which is axially movable and defines the working chamber 41.

[0034] As in Fig. As shown in Figure 2, the high-pressure plunger pump 1 in the embodiment shown here has three plunger housings 3, in each of which a plunger 42 is guided.

[0035] The high-pressure plunger pump 1 further comprises a number of valve bodies 5, corresponding to the number of plungers 42, arranged in respective receptacles of the pump head 2 and the plunger housing 3, each with an inlet valve 6 and an outlet valve 7.

[0036] As in the Fig. 3 and Fig. As shown in Figure 6, the plunger(s) 42 are coupled to a respective (not shown) crankshaft via a connecting rod A to execute the axial movement. The crankshaft A is driven, for example, by an electric motor.

[0037] It is also conceivable to have a plunger arrangement 4 with more than three plungers 42, for example five, seven or ten plungers 42 as well as a corresponding number of associated valve bodies 5 and inlet and outlet valves 6, 7.

[0038] What next in the Fig. 3 and Fig. As shown in Figure 6, the high-pressure plunger pump 1 has a suction port 21 for connecting a supply line 11 and a pressure port 24 for connecting a high-pressure outlet 8.

[0039] In order to meet the high safety requirements mentioned above, the plunger housing 3 with the plunger assembly 4 arranged therein is surrounded by a chamber wall 19.

[0040] Furthermore, a cap 9 with a suction port opening 91 and a pressure port opening 92 is placed on the pump head 2.

[0041] With the supply line 11 and the high-pressure outlet 8 connected, the cap 9 and the chamber wall 19 enclose the pump head 2 and the plunger housing 3 in a fluid-tight manner, so that the fluid-carrying components pump head 2 and plunger arrangement 4 are enclosed by a second wall in the form of the cap 9 and the chamber wall 19 in a fluid-tight manner.

[0042] This prevents any potential leakage of the fluid, for example a fuel, which is pressurized to a pressure of preferably between 100 bar and 2000 bar in the high-pressure plunger pump 1, from escaping to the outside.

[0043] The valve body 5, which is known per se, exhibits, as in the Fig. 3 and Fig. Figure 6 shows a through channel 51 adjoining the working chamber 41 and used as a suction channel, through which a fluid, for example a fuel necessary for operating an internal combustion engine, is introduced via the supply line 11 into a valve receiving chamber 22, to which the through channel 51 is open.

[0044] The through-channel 51, used as a suction channel, can be closed by the inlet valve 6.

[0045] During the suction stroke of the plunger 42, the inlet 61 of the inlet valve 6 is opened, so that the fluid is drawn into the working chamber 41 of the plunger arrangement 4, which increases in size during the suction stroke.

[0046] In the subsequent pressure stroke of the plunger 42, the fluid in the working chamber 41 is compressed and forced through a second passage 52 of the valve body 5 towards an outlet valve 7.

[0047] The outlet valve 7 opens at a predetermined pressure, allowing the high-pressure fluid to flow through an outlet of the outlet valve 7 into a pressure chamber 23, where the high-pressure fluid is then conveyed via a high-pressure passage 25 to the high-pressure outlet 8.

[0048] The supply line 11 and the high-pressure outlet 8 are also double-walled.

[0049] The high-pressure outlet 8 essentially consists of an inner tube 81 adjoining the high-pressure passage 25, in which a fluid passage 83 is formed.

[0050] This inner tube 81 is surrounded by an outer tube 82, which is inserted into a connector 84. The connector 84 itself is inserted through the pressure port 92 of the cap 9 into the pressure port 24 of the pump head 2, as shown in Fig. 2 is shown as an example.

[0051] What next in the Fig. 2 and Fig. As shown in Figure 3, in the preferred embodiment of the high-pressure plunger pump 1 shown here, an adapter 10 is inserted between the cap 9 and the chamber wall 19, so that the cap 9 and the adapter 10 on the one hand and the chamber wall 19 and the adapter 10 on the other hand are mounted fluid-tight against each other.

[0052] It is also conceivable that the cap 9 and the chamber wall 19 form a single, one-piece component, in the Fig. 5 and Fig. 6, marked with reference 9, form.

[0053] What next in the Fig. 2, Fig. 3 and Fig. As shown in Figure 6, cavities H1 and H2 are formed between the cap 9 and the pump head 2 on the one hand, and between the chamber wall 19 and the plunger housing 3 on the other.

[0054] A channel 20 is provided between a low-pressure seal 12 and a high-pressure seal 43 in order to direct the leakage of the high-pressure seal 43 occurring at the plunger 42, which occurs particularly when the high-pressure seal 43 is designed as a gap seal, on the suction side with lower pressure in the area of ​​the low-pressure seal 12 between an outer wall of the plunger housing 3 and a sleeve 33 surrounding the plunger housing 3 into the cavity 32 and from there into the valve receiving chamber 22 of the pump head 2.

[0055] The channel 20 is preferably incorporated into a section of a low-pressure sealing housing 121, to which the low-pressure seals 12 are also attached.

[0056] Such a low-pressure seal 12 of the plunger housing 3 towards the plunger 42 is in the Fig. 3, Fig. 4 and Fig. Figure 6 is shown as an example. The plunger 42 is sealed here by two low-pressure seals 12 and additionally by the barrier medium 13.

[0057] The low-pressure seal 12 is preferably designed as a packing seal.

[0058] The barrier medium 13 is preferably supplied to and discharged from the low-pressure seal 12 via a supply channel 14 provided in the sealing housing 121 and via a discharge channel 15 provided in the sealing housing 121, as is well known in Fig. 3 or Fig. 6 is recognizable.

[0059] What next in the Fig. 1, Fig. 2 to Fig. As shown in Figure 3, the suction port 21 is located on the pump head 2.

[0060] During the Fig. 5 and Fig.In the embodiment shown in 6, the suction port 21 is provided on the chamber wall 19, with the cap 9 fluid-tightly enclosing the chamber wall 19 and the pump head 2.

[0061] In this design variant, the cavity H1 between the cap 9 and the pump head 2 extends into an area between the cap 9 and the chamber wall 19.

[0062] In this design variant, any potential leaks can be returned to the valve receiving chamber via the cavity between the chamber wall and the plunger housing, while maintaining a double-walled seal to prevent the escape of high-pressure fuel in the high-pressure plunger pump. A sleeve 33 surrounding the plunger housing 3 for leakage return is not required here.

[0063] It is also conceivable to drain the leaking fluid externally via a double-walled pipe.

[0064] If leakage fluid should pass the low-pressure seal 12 and continue downwards, the escaping leakage fluid can be collected in a crank drive space 18 and drained from there.

[0065] This crank drive space 18 forms a further hermetic barrier by means of a bellows 16 surrounding the plunger 42 and cover plates 17. Reference symbol list 1 high-pressure plunger pump 2 Pump head 21 Suction port 22 Valve receiving chamber 23 Printing room 24 Pressure connection 25 High-pressure passage 3 plunger housings 31 Suction chamber 32 Cavity 33 Sleeve 4 Plunger arrangement 41 Workroom 42 plungers 43 High-pressure seal 5 valve bodies 51 Through channel 52 through channel 6 Inlet valve 61 Admission 7 Exhaust valve 71 Outlet 8 High-pressure outlet 81 Inner tube 82 Outer pipe 83 Fluid passage 84 connector 9 cap 91 Suction port opening 92 Pressure connection opening 10 adapters 11 Supply line 12 Low-pressure sealing 121 Sealing housing 13 Blocking medium 14 Feed channel 15 Drainage channel 16 bellows 17 Cover plate 18 Crankshaft drive space 19 chamber wall 20 channels X direction Y direction Z direction A connecting rod H1 cavity H2 cavity

Claims

A high-pressure plunger pump (1) comprising: a pump head (2), a plunger housing (3) attached to the pump head (2), a plunger assembly (4) arranged in the plunger housing (3) with at least one working chamber (41) and at least one axially movable plunger (42) delimiting the working chamber (41), a number of valve bodies (5) corresponding to the number of plungers (42) arranged in respective receptacles of the pump head (2) and the plunger housing (3) with an inlet valve (6) and an outlet valve (7), a suction port (21) for connecting a supply line (11) and a pressure port (24) for connecting a high-pressure outlet (8), characterized in that: the plunger housing (3) with the plunger assembly (4) arranged therein is surrounded by a chamber wall (19), and a cap (9) with a suction port opening (91) is placed on the pump head (2). and is attached to a pressure connection opening (92),- wherein the cap (9), with the supply line (11) and high-pressure outlet (8) connected, together with the chamber wall (19), fluid-tightly encloses the pump head (2) and the plunger housing (3). High-pressure plunger pump (2) according to claim 1, characterized in that an adapter (10) is inserted between the cap (9) and the chamber wall (19), so that the cap (9) and the adapter (10) on the one hand and the chamber wall (19) and the adapter (10) on the other hand are mounted fluid-tight to each other. High-pressure plunger pump according to claim 1, characterized in that the cap (9) and the chamber wall (19) form a common one-piece component. High-pressure plunger pump according to one of the preceding claims, characterized in that a cavity (H1, H2) is formed between the cap (9) and the pump head (2) on the one hand and the chamber wall (19) and the plunger housing (3) on the other hand. High-pressure plunger pump according to one of the preceding claims, characterized in that a seal between the plunger housing (3) and the plunger (42) is formed by at least one low-pressure seal (12) and / or a barrier medium (13). High-pressure plunger pump according to claim 5, characterized in that the seal of the plunger housing (3) to the plunger (42) is formed by two low-pressure seals (12) and the barrier medium (13), wherein the barrier medium (13) is provided between the two low-pressure seals (12). High-pressure plunger pump according to claim 5 or 6, characterized in that the low-pressure seal (12) is designed as a packing seal. High-pressure plunger pump according to one of claims 5 to 7, characterized in that the barrier medium (13) can be supplied to and discharged from the low-pressure seal (12) via a supply channel (14) provided in a sealing housing (121) and via a discharge channel (15) provided in the sealing housing (121). High-pressure plunger pump according to one of claims 5 to 8, characterized in that the plunger housing (3) is surrounded by a sleeve (33), wherein at least one cavity (32) is formed between the sleeve (33) and an outer wall of the plunger housing (3), which is fluidly connected via channels (20) to the valve receiving chamber (22) and the low-pressure seal. High-pressure plunger pump according to one of the preceding claims, characterized in that the suction port (21) is provided on the pump head (2). High-pressure plunger pump according to one of the preceding claims 1 to 8, characterized in that the suction port (21) is provided on the chamber wall (19), wherein the cap (9) fluid-tightly surrounds the chamber wall (19) and the pump head (2), wherein a cavity (H1) between the cap (9) and the pump head (2) extends into a region between the cap (9) and the chamber wall (19). High-pressure plunger pump according to one of the preceding claims, characterized in that the plunger arrangement (4) has at least three plungers (42).

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