JP7680328B2 - Reciprocating Pump - Google Patents

Description

The present invention relates to a reciprocating pump.

Patent Document 1 discloses a reciprocating pump. This pump includes a manifold in which a valve chamber having an insertion port is formed, a valve assembly inserted into the valve chamber through the insertion port, an adapter fitted into the insertion port of the valve chamber and abutting against the valve assembly, and a lid fixed to the insertion port side of the manifold so as to press the adapter toward the valve assembly. The adapter has a sealing member (O-ring) that is in close contact with the inner circumference of the valve chamber, preventing the fluid in the valve chamber from leaking to the outside. The adapter pressed against the lid presses the valve assembly via a spring, and the valve assembly is pressed against the opposite side of the insertion port within the valve chamber.

JP 2003-328956 A

In a reciprocating pump like the one described above, the pressure inside the valve chamber fluctuates as the plunger reciprocates, and this pressure fluctuation causes the valve assembly to open and close. Meanwhile, the adapter that presses the valve assembly can reciprocate due to the influence of the pressure fluctuation. That is, the adapter can move toward the lid when pressure is applied inside the valve chamber, and can move away from the lid when negative pressure is applied inside the valve chamber. When the adapter repeatedly reciprocates, the sealing member installed in the adapter deteriorates, making it more likely to leak.

The present invention aims to provide a reciprocating pump that can suppress the occurrence of water leakage.

In one example of a reciprocating pump, a reciprocating member (40) reciprocates within a cylinder portion (21), thereby performing a pumping action in a pump chamber (11) provided at the tip of the cylinder portion (21). This reciprocating pump includes a manifold (10) having a pump chamber (11), a valve assembly (50) housed in the manifold (10), and a positioning mechanism (60) for positioning the valve assembly (50). The manifold (10) includes a cylindrical space (15) in which the valve assembly (50) is housed, and an opening (15c) that is the axial end of the cylindrical space (15). The positioning mechanism (60) includes a cover (61) that closes the opening (15c) of the manifold (10), and a plug (65) that has a sealing member (66c) that is in close contact with the inner circumferential surface of the cylindrical space (15) and is fixed to the inner surface of the cover (61) to press the valve assembly (50) against the opening (15c) of the cylindrical space (15).

In the above reciprocating pump, the plug (65) having the sealing member (66c) is fixed to the lid (61), so that the reciprocating movement of the plug (65) caused by pressure fluctuations in the pump chamber (11) is suppressed. Therefore, deterioration of the sealing member (66c) provided on the plug (65) is suppressed, and the occurrence of water leakage is also suppressed.

In one example, the plug (65) may have a flange-shaped portion (67) located between the end face (15e) where the opening (15c) is formed and the lid (61). In this configuration, it is possible to increase the contact area between the plug (65) and the lid (61) by the area of the flange-shaped portion (67).

In one example, a recess (63) is formed on the inner surface of the lid (61), and the flange-shaped portion (67) may be housed in the recess (63). In this configuration, the contact position between the lid (61) and the end face (15e) where the opening (15c) is formed and the contact position between the lid (61) and the plug (65) are shifted by the thickness of the recess (63).

In one example, a notch (67a) may be formed on the periphery of the flange-shaped portion (67) to form a space between the bottom surface of the recess (63). In this configuration, when grease is applied between the lid body (61) and the plug (65), the grease that spills out from between the lid body (61) and the plug (65) tends to remain in the notch (67a).

In one example, the lid (61) is formed with a through hole (63a) that penetrates the lid (61) in the thickness direction, and the plug (65) may be fixed to the lid (61) by a fastening member (64) that is inserted into the through hole (63a) from the outside of the lid (61). In this configuration, the fastening member (64) is prevented from coming into contact with the fluid used.

In this way, according to one aspect of the present invention, it is possible to provide a reciprocating pump that suppresses the occurrence of water leakage.

FIG. 1 is a cross-sectional view of an example reciprocating pump. FIG. 2 is an enlarged cross-sectional view showing the reciprocating pump of FIG. 1 .

An example of a reciprocating pump will be described below with reference to the attached drawings. In this specification, as an example of a reciprocating pump, a so-called horizontal triple plunger pump in which the plungers constituting the reciprocating members are arranged in three rows in the horizontal direction will be described. In the following description, "upper" and "lower" are defined based on the state in which the reciprocating pump is placed on a horizontal surface, and "front" and "rear" are defined based on the axial direction of the reciprocating member, with the pump chamber side being the front and the crankcase side being the rear.

Figure 1 is a cross-sectional view showing one of three plunger pumps that make up a reciprocating pump. In one example of a reciprocating pump 1, three pump configurations shown in Figure 1 are arranged side by side in the left-right direction (perpendicular to the plane of the drawing). Figure 2 is a partially enlarged view of Figure 1. As shown in Figure 1, the reciprocating pump 1 performs pumping action in a pump chamber provided at the tip of the cylinder portion by reciprocating members 40 within the cylinder portion.

The reciprocating pump 1 has an outer shape formed by a first manifold 10 having a pump chamber 11, a second manifold 20 having a cylinder portion 21 communicating with the pump chamber 11 and connected to the first manifold 10, and a crankcase 30 connected to the second manifold 20. The first manifold 10, the second manifold 20, and the crankcase 30 are integrally connected by fixing the first manifold 10 to the crankcase 30 via the second manifold 20 with a plurality of fastening means (e.g., bolts, etc.). In the illustrated example, the first manifold 10 is a discharge manifold, and the second manifold 20 is a water intake manifold. In addition, in the part above the axis L in Figures 1 and 2, the reciprocating member 40 is shown in a state where it has advanced and is located at the top dead center, and the part below the axis L is shown in a state where it has retreated and is located at the bottom dead center.

The crankcase 30 is hollow. Inside the crankcase 30, a crankshaft 32, a connecting rod 33 rotatably connected to the crankshaft 32, a piston pin 35 rotatably connecting a plunger rod 41 to the connecting rod 33, etc. are arranged, and these constitute a drive unit that drives the reciprocating member 40 to reciprocate along the axis L. The crankcase 30 includes a cylinder portion 31 that shares a central axis with the cylinder portion 21. The cylinder portion 31 is cylindrical and has an axial direction perpendicular to the axial direction of the crankshaft 32. The piston pin 35 and the tip of the connecting rod 33 can be arranged inside the cylinder portion 31.

The crankcase 30 is filled with oil for lubricating and cooling the drive unit. An oil seal 36 is disposed at the end of the cylinder section 31 on the second manifold 20 side to prevent leakage of oil from the crankcase 30. The oil seal 36 is in liquid-tight sliding contact with the outer circumferential surface of the plunger rod 41 that constitutes the reciprocating member 40. When the crankshaft 32 rotates, the reciprocating member 40 reciprocates back and forth via the connecting rod 33 and piston pin 35.

The second manifold 20, which abuts against the crankcase 30, is provided with an intake port 22 for introducing the liquid to be used, such as water, into the pump chamber 11, and the first manifold 10, which abuts against the second manifold 20, is provided with an outlet port 12 (see FIG. 2) for discharging the liquid to be used compressed in the pump chamber 11. A valve assembly 50 is provided as an intake valve in the flow path that communicates between the intake port 22 and the pump chamber 11, and a valve assembly 70 is provided as a discharge valve in the flow path that communicates between the pump chamber 11 and the discharge port 12.

The first manifold 10 and the second manifold 20 are connected via a communicating pipe 23. In the illustrated example, a coil spring 24 is disposed on the crankcase 30 side of the communicating pipe 23, and a high-pressure seal 25 is disposed on the crankcase 30 side of this coil spring 24. In other words, the coil spring 24 is disposed between the communicating pipe 23 and the high-pressure seal 25, and presses the communicating pipe 23 and the high-pressure seal 25 in opposite directions along the axial direction.

The high-pressure seal 25 is intended to prevent the liquid in use from leaking from the pump chamber 11 to the crankcase 30 between the plunger 43 that constitutes the front half of the reciprocating member 40 and the pump chamber 11, and is housed within the second manifold 20.

In addition, a low-pressure seal 26 with a lower sealing pressure than the high-pressure seal 25 is disposed in the cylinder section 21 of the second manifold 20 at a position closer to the crankcase 30 than the high-pressure seal 25. The low-pressure seal 26 slides against the plunger 43 to provide a liquid-tight seal inside the cylinder section 21.

The communicating pipe 23 is formed into a cylindrical shape, for example, from a metal. The outer diameter of the communicating pipe 23 is approximately the same as the outer diameter of the high-pressure seal 25. The communicating pipe 23 is housed straddling the first manifold 10 and the second manifold 20.

The communicating tube 23 has a gap between its inner circumferential surface and the outer circumferential surface of the plunger 43 through which the plunger 43 is inserted. An O-ring 27 (see FIG. 2) is disposed between the first manifold 10 and the outer circumferential surface of the communicating tube 23. An O-ring 28 (see FIG. 2) is disposed between the second manifold 20 and the outer circumferential surface of the communicating tube 23. These O-rings 27, 28 prevent the liquid used from leaking along the outer circumferential surface of the communicating tube 23.

As shown in FIG. 2, the first manifold 10 contains a valve assembly 50 for intake and a valve assembly 70 for discharge. The first manifold 10 is also provided with a positioning mechanism 60 for positioning the valve assembly 50 for intake and a positioning mechanism 80 for positioning the valve assembly 70 for discharge.

The first manifold 10 includes a first cylindrical space 15 in which the valve assembly 50 is housed. The first cylindrical space 15 may be, for example, a substantially cylindrical space along the axial direction of the piston. One axial end of the first cylindrical space 15 is an opening 15a that communicates with the suction port 22 of the second manifold 20. An opening 15b that communicates with the pump chamber 11 in the first manifold 10 is provided in the side wall of the first cylindrical space 15. The other axial end of the first cylindrical space 15 is an opening 15c in which the positioning mechanism 60 is provided. The valve assembly 50 is provided between the opening 15b that communicates with the pump chamber 11 and the opening 15a that communicates with the suction port 22, and functions as a water intake valve.

An example of the valve assembly 50 includes a cylindrical valve seat 51, a valve 52 that seals the valve seat 51, a biasing member (compression coil spring) 53 that biases the valve 52 toward the valve seat 51, and a housing 55 that accommodates the biasing member 53 and the valve 52. The valve seat 51 has an inlet side opening 51a and an outlet side opening 51b. An O-ring 51c, for example, is provided on the outer periphery of the inlet side opening 51a. The valve seat 51 is disposed in the first cylindrical space 15 so that the inlet side opening 51a faces the suction port 22, and the O-ring 51c seals between the inner periphery of the first cylindrical space 15 and the outer periphery of the valve seat.

A flange 51d that protrudes outward is formed on the outer periphery of the outflow side of the valve seat 51. In the illustrated example, a step 15d is formed at the opening on the suction port 22 side of the first cylindrical space 15, and the flange 51d of the valve seat 51 is engaged with this step 15d.

The outlet opening 51b of the valve seat 51 is the portion sealed by the valve 52. The valve 52 has an abutment surface that corresponds to the shape of the outlet opening 51b of the valve seat 51. The abutment surface abuts against the outlet opening 51b of the valve seat 51, thereby sealing the outlet opening 51b of the valve seat 51 with the valve 52. The container 55 has, for example, a substantially cylindrical shape, and contains the biasing member 53 and the valve 52 inside. The peripheral wall 55a of the container 55 may have an opening (such as a slit) for passing the used fluid. The valve assembly 50 is assembled by pressing the outlet opening 51b of the valve seat 51 into the inlet end of the container 55 with the biasing member 53 and the valve 52 contained in the container 55.

The positioning mechanism 60 includes a lid 61 and a plug 65. The lid 61 is a member that closes the opening 15c of the first manifold 10. The lid 61 in one example is substantially plate-shaped and includes a through hole 61a through which a bolt 62 is inserted to fix the lid 61 to the first manifold 10. When the lid 61 is fixed to the first manifold 10, the inner surface of the lid 61 is in contact with an end surface 15e in which the opening 15c of the first manifold 10 is formed. The end surface 15e has a bolt hole 15e1 for the bolt 62 at a position corresponding to the through hole 61a of the lid 61.

A recess 63 is formed on the inner surface of the lid 61. The recess 63 has a circular shape when viewed from the axial direction of the first cylindrical space 15. The diameter of the recess 63 is larger than the diameter of the first cylindrical space 15. For example, the axis of the first cylindrical space 15 may pass through the center of the recess 63.

The lid 61 also has a through hole 63a that penetrates the lid 61 in the thickness direction. A bolt 64 for fixing the plug 65 to the lid 61 is inserted into this through hole 63a. The through hole 63a in the illustrated example is formed to pass through the center of the recess 63 formed in the lid 61.

The plug 65 is fixed to the lid 61 by a bolt (fastening member) 64 inserted into the through hole 63a from the outside of the lid 61. When the plug 65 is fixed to the inner surface of the lid 61, it presses the valve assembly 50 against the opening 15c of the first cylindrical space 15. The plug 65 in the illustrated example has a cylindrical portion 66 having a bottom and a ring-shaped flange portion 67 protruding radially outward from the end of the bottom side of the cylindrical portion 66. The outer diameter of the cylindrical portion 66 is approximately the same as the inner diameter of the first cylindrical space 15, and the cylindrical portion 66 is inserted into the first cylindrical space 15. A bolt hole 66b is provided in the center of the bottom 66a of the cylindrical portion 66, into which the bolt 64 inserted into the through hole 63a of the lid 61 is screwed. The bolt hole 66b does not penetrate the bottom 66a of the cylindrical portion 66. The depth of the bolt hole 66b is not particularly limited.

The outer diameter of the flange portion 67 is larger than the diameter of the first cylindrical space 15 and smaller than the diameter of the recess 63 of the lid body 61. The thickness of the flange portion 67 may be approximately the same as the depth of the recess 63 of the lid body 61. The flange portion 67 is housed within the recess 63 of the lid body 61 and is located between the end face 15e where the opening 15c is formed and the lid body 61.

A notch 67a is formed on the periphery of the flange-shaped portion 67 to form a space between the flange-shaped portion 67 and the bottom surface of the recess 63. The notch 67a is formed around the entire periphery of the flange-shaped portion 67. One example of the notch 67a is formed by cutting out a corner of the periphery of the flange-shaped portion 67. In other words, the space formed by the notch 67a between the flange-shaped portion 67 and the bottom surface of the recess 63 is an annular space with a triangular cross section.

The plug 65 has a sealing member 66c that is in close contact with the inner circumferential surface of the first cylindrical space 15. In one example, a groove is formed in the circumferential direction on the outer circumferential surface of the cylindrical portion 66 of the plug 65, and an O-ring is provided in the groove as the sealing member 66c. When the cylindrical portion 66 is inserted into the first cylindrical space 15, the O-ring seals the gap between the plug 65 and the first cylindrical space 15.

The plug 65 in one example presses the valve assembly 50 via a biasing member 68. For example, the biasing member 68 may be a compression coil spring. When the biasing member 68 is housed in the internal space of the cylindrical portion 66 of the plug 65, it abuts against the housing 55 of the valve assembly 50 and presses the valve assembly 50 in the opposite direction to the opening 15c of the first cylindrical space 15.

The first manifold 10 also includes a second cylindrical space 16 in which a discharge valve assembly 70 is housed. The second cylindrical space 16 may be, for example, a substantially cylindrical space. The axial direction of the second cylindrical space 16 intersects (is perpendicular to) the axial direction of the piston. An opening 16a at one axial end of the second cylindrical space 16 communicates with the pump chamber 11. An opening 16b communicating with the discharge port 12 is provided in the side wall of the second cylindrical space 16. The other axial end of the second cylindrical space 16 is an opening 16c in which a positioning mechanism 80 is provided. The valve assembly 70 is provided between the opening 16a communicating with the pump chamber 11 and the opening 16b communicating with the discharge port 12, and functions as a discharge valve.

An example of the valve assembly 70 has a similar configuration to the valve assembly 50, and includes a cylindrical valve seat 71, a valve 72 that seals the valve seat 71, a biasing member (compression coil spring) 73 that biases the valve 72 toward the valve seat 71, and a housing 75 that accommodates the biasing member 73 and the valve 72. The valve seat 71, the valve 72, the biasing member 73, and the housing 75 may each have a similar structure to the valve seat 51, the valve 52, the biasing member 53, and the housing 55 that constitute the valve assembly 50.

The valve assembly 70 is disposed in the second cylindrical space 16 with the valve seat 71 facing the pump chamber 11. In the illustrated example, a step 16d is formed in the opening 16a on the pump chamber 11 side of the second cylindrical space 16, and a flange 71d of the valve seat 71 is engaged with this step 16d. The O-ring 71c of the valve seat 71 provides a seal between the inner periphery of the flow passage that connects the pump chamber 11 to the second cylindrical space 16 and the outer periphery of the valve seat 71.

The positioning mechanism 80 has a similar configuration to the positioning mechanism 60, and includes a lid 81 and a plug 85. The lid 81 and the plug 85 may have the same structure as the lid 61 and the plug 65 constituting the positioning mechanism 60. The lid 81 closes the opening 16c of the first manifold 10. The lid 81 in one example is substantially plate-shaped and includes a through hole 81a through which a bolt 82 for fixing the lid 81 to the first manifold 10 is inserted. When the lid 81 is fixed to the first manifold 10, the inner surface of the lid 81 is in contact with the end surface 16e in which the opening 16c of the first manifold 10 is formed. The end surface 16e has a bolt hole 16e1 for the bolt 82 at a position corresponding to the through hole 81a of the lid 81.

The cylindrical portion 86 of the plug 85 fixed to the lid 81 is inserted into the second cylindrical space 16 when the lid 81 is fixed to the first manifold 10. When the cylindrical portion 86 is inserted into the second cylindrical space 16, the plug 85 and the second cylindrical space 16 are sealed by a sealing member (O-ring) 86c provided on the cylindrical portion 86.

The plug 85 in one example presses the valve assembly 70 via a biasing member 88, such as a compression coil spring. The biasing member 88, when housed in the internal space of the cylindrical portion 86 of the plug 85, abuts against the housing 75 of the valve assembly 70 and presses the valve assembly 70 in the opposite direction to the opening 16c of the second cylindrical space 16.

As described above, the reciprocating pump 1 performs pumping action in the pump chamber 11 provided at the tip of the cylinder portion 21 by the reciprocating member 40 reciprocating in the cylinder portion 21. This reciprocating pump 1 includes a first manifold 10 having a pump chamber 11, a valve assembly 50 housed in the first manifold 10, and a positioning mechanism 60 for positioning the valve assembly 50. The first manifold 10 includes a first cylindrical space 15 in which the valve assembly 50 is housed, and an opening 15c that is the axial end of the first cylindrical space 15. The positioning mechanism 60 includes a cover 61 that closes the opening 15c of the first manifold 10, and a plug 65 that has a sealing member 66c that is in close contact with the inner circumferential surface of the first cylindrical space 15 and is fixed to the inner surface of the cover 61 and presses the valve assembly 50 in the opposite direction to the opening 15c of the first cylindrical space 15.

In the reciprocating pump 1, the crankshaft 32 rotates, causing the reciprocating member 40 connected to the crankshaft 32 via the connecting rod 33 and piston pin 35 to reciprocate. During the intake stroke, the reciprocating member 40 moves backward toward the drive unit, creating a negative pressure in the pump chamber 11. When the pump chamber 11 becomes negative pressure, the intake valve assembly 50 opens and the discharge valve assembly 70 closes. As a result, the liquid used is sucked into the pump chamber 11 through the intake port 22 and the valve assembly 50. During the discharge stroke, the reciprocating member 40 moves forward toward the pump chamber 11, pressurizing the pump chamber 11. When the pump chamber 11 is pressurized, the intake valve assembly 50 closes and the discharge valve assembly 70 opens. As a result, the liquid used in the pump chamber 11 is discharged to the discharge port 12 through the valve assembly 70.

Consider the case where the plug 65 is not fixed to the lid 61 in such a reciprocating pump. For example, in the illustrated example, the depth of the recess 63 of the lid 61 and the thickness of the flange 67 of the plug 65 are manufactured to be the same, but a tolerance gap may be formed between the flange 67 and the recess 63 in the axial direction. In this case, when the pressure in the pump chamber 11 fluctuates with the reciprocating movement of the reciprocating member 40, the plug 65 pressing the valve assembly 50 may reciprocate (vibrate) in the axial direction in the first cylindrical space 15 due to the influence of the pressure fluctuation. That is, the plug 65 may move toward the lid 61 when the pump chamber 11 is pressurized, and move away from the lid 61 when the pump chamber 11 becomes negative pressure. When the plug 65 repeatedly reciprocates, the sealing member 66c provided on the plug 65 rubs against the inner surface of the first cylindrical space 15, causing deterioration of the sealing member 66c and making it easier for water leakage to occur.

In the reciprocating pump 1 according to this embodiment, the plug 65 having the sealing member 66c is fixed to the lid 61, so that the reciprocating movement of the plug 65 caused by pressure fluctuations in the pump chamber 11 is suppressed. This suppresses deterioration of the sealing member 66c provided on the plug 65, and thus suppresses the occurrence of water leakage. In addition, in the positioning mechanism 80 that positions the discharge valve assembly 70, the same action as above suppresses deterioration of the sealing member 86c provided on the plug 85, and thus suppresses the occurrence of water leakage.

In one example, the plug 65 has a flange-shaped portion 67 located between the end face 15e where the opening 15c is formed and the lid body 61. In this configuration, it is possible to increase the contact area between the plug 65 and the lid body 61 by the area of the flange-shaped portion 67. This makes it possible to reduce the pressure that the lid body 61 receives from the plug 65 when the inside of the pump chamber 11 is pressurized.

In one example, a recess 63 may be formed on the inner surface of the lid body 61, and the flange-shaped portion 67 may be housed within the recess 63. In this configuration, the contact position between the lid body 61 and the end face 15e and the contact position between the lid body 61 and the plug 65 are shifted in the axial direction by the depth of the recess 63. In this configuration, when grease is applied between the lid body 61 and the plug 65, the grease that overflows from between the lid body 61 and the plug 65 is unlikely to move to the contact position between the lid body 61 and the end face 15e. Therefore, leakage of the grease to the outside of the lid body 61 is suppressed.

In one example, a notch 67a is formed on the periphery of the flange portion 67 to form a space (grease pocket) between the bottom surface of the recess 63. In this configuration, when grease is applied between the lid body 61 and the plug 65, the grease that spills out from between the lid body 61 and the plug 65 tends to accumulate in the notch 67a. This prevents the grease from leaking outside the lid body 61.

In one example, the lid 61 is formed with a through hole 63a that penetrates the lid 61 in the thickness direction, and the plug 65 is fixed to the lid 61 by a bolt 64 (fastening member) that is inserted into the through hole 63a from the outside of the lid 61. In this configuration, the bolt 64 is prevented from coming into contact with the fluid used.

The above describes an embodiment of the present invention, but the specific form of the present invention is not limited to the above example.

For example, although an example has been shown in which the plug 65 presses against the valve assembly 50 via the biasing member 68, the plug 65 may press against the valve assembly 50 directly without using an indirect member such as a biasing member.

Reference Signs List 1...reciprocating pump, 10...first manifold, 11...pump chamber, 15...first cylindrical space (cylindrical space), 15c...opening, 20...second manifold, 21...cylinder portion, 30...crankcase, 40...reciprocating member, 50, 70...valve assembly, 60, 80...positioning mechanism, 61, 81...cover, 65, 85...plug.

Claims (5)

A reciprocating pump in which a reciprocating member (40) reciprocates within a cylinder portion (21) to perform a pumping action in a pump chamber (11) provided at a tip of the cylinder portion (21),
a manifold (10) having the pump chamber (11);
a valve assembly (50) contained within the manifold (10);
a positioning mechanism (60) for positioning the valve assembly (50);
The manifold (10) includes a cylindrical space (15) in which the valve assembly (50) is housed, and an end surface (15e) in which an opening (15c) serving as an axial end of the cylindrical space (15) is formed ,
The positioning mechanism (60)
a cover (61) that abuts against the end surface (15e) of the manifold (10) to close the opening (15c);
a plug (65) having a sealing member (66c) that is in close contact with the inner peripheral surface of the cylindrical space (15) and that presses the valve assembly (50) against the side opposite the opening (15c) of the cylindrical space (15) while being fixed to the inner surface of the lid body (61). 2. The reciprocating pump according to claim 1, wherein the plug (65) has a flange-shaped portion (67) located between the end face (15e) in which the opening (15c) is formed and the lid body (61). A recess (63) is formed on the inner surface of the lid (61),
3. The reciprocating pump of claim 2, wherein the flange portion (67) is housed within the recess (63). The reciprocating pump according to claim 3, wherein a notch (67a) is formed on the periphery of the flange portion (67) to form a space between the flange portion and the bottom surface of the recess (63). The lid (61) has a through hole (63a) formed therein, the through hole (63a) penetrating the lid (61) in a thickness direction,
The reciprocating pump according to any one of claims 1 to 4, wherein the plug (65) is fixed to the lid body (61) by a fastening member (64) inserted into the through hole (63a) from the outside of the lid body (61).

Images