JP2001123940A - Reciprocating pump device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sub triple plunger pump device with simple structure and advantageous for size reduction. SOLUTION: The sub triple plunger pump device 55 comprises three sub reciprocating pumps 60a, 60b, 60c, which are disposed in a clank case 11 of a main triple piston pump device 10, and are driven by a common crankshaft 24. Cylindrical holes 76 of the sub reciprocating pumps 60a, 60b, 60c are communicated with each other by communicating holes 73 in such a manner that the cylindrical holes 76 neighboring to each other in an axial direction of the crankshaft 24 are communicated with each other. The sub reciprocating pump on an intake port 70 side is operated with a phase advanced from the sub reciprocating pump on a discharge port 71 side by θ (0 deg.<θ<108 deg.). The discharge port 71, a pump chamber 72, and the communicating holes 73 are closed when the corresponding plungers 64 are in a rotational angle range of ±30 deg. with respect to the upper dead center.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a reciprocating pump device such as a triple piston pump device, and more particularly to a reciprocating pump device advantageous for downsizing.

[0002]

2. Description of the Related Art For example, in a triple piston pump device installed in a washing machine or the like, a plurality of reciprocating pumps are arranged in a line in the axial direction of a crankshaft, and are commonly driven by the crankshaft. ing.

[0003]

In a large reciprocating pump device, an oil pump is separately provided. However, in a small reciprocating pump device, separately installing an oil pump is very limited due to space and cost. You.

An object of the present invention is to provide a novel reciprocating pump device which is advantageous for simplifying the structure and reducing the size.

[0005]

According to the reciprocating pump device (55, 85) of the present invention, a plurality of reciprocating pumps (60a, b, c) are provided.
The pump chambers (72) are connected in series and are operated by a common or separate drive shaft (24). In this reciprocating pump device (55, 85), each reciprocating pump (60a, b, c) reciprocates in the cylinder member (76) by driving the drive shaft (24), and the pump in the cylinder member (76) reciprocates. A reciprocating member (63, 86) for increasing or decreasing the volume of the chamber (72) is provided. The reciprocating pumps (60a, b, c) at one end and the other end of the series connection are reciprocating pump devices (55, 8
5) It has a suction port (70) and a discharge port (71) as a whole. The reciprocating pumps (60a, b, c) whose connection relationship is adjacent to each other have their cylinder members (76) connected to each other by a connection passage (73), and the connection passage (73) is connected to the pump chamber.
The communication with the reciprocating member (63, 86) is established by the reciprocating members (63, 86) as the reciprocating members (63, 86) reciprocate. In the reciprocating pumps (60a, b, c) whose connection relationship is adjacent to each other, the reciprocating pump (60a, b, c) on the suction port side is reciprocating pump (60a, b, c) on the discharge port side.
The connection passage (73), which is operated in a phase advanced by θ (0 ° <θ <180 °) from c) and communicates with the cylinder member (76) of the reciprocating pumps (60a, b, c), has a reciprocating pump. In the predetermined rotation angle range including the top dead center of the reciprocating member (63, 86) of (60a, b, c) (the rotation angle is defined by the rotation angle of the drive shaft (24)), it is closed. The position has been set.

The reciprocating pump device (55, 85) includes a multiple reciprocating pump device. The multiple reciprocating pump device means a device in which a plurality of reciprocating pumps are driven by a common drive shaft. In the reciprocating pump device (55, 85), the phase difference between the reciprocating pumps (60a, b, c) whose connection relationship is adjacent to each other may be equal or different. Drive shaft
(24) is not limited to the crankshaft. The drive shaft (24) may include, for example, an eccentric circular cam, and the large end of the connecting rod (25) may be fitted to the circular cam.

The moving speed of the reciprocating member (63, 86) becomes zero at the top dead center and the bottom dead center. In the following description, the reciprocating member (63,86)
With regard to the moving speed, the suction stroke is positive and the discharge stroke is negative. If the reciprocating pump (60a,
If the pump chambers (72) of (b, c) are in communication with each other, the moving speed of the reciprocating member (63, 86) is changed from the smaller pump chamber (72) of the reciprocating member (63, 86). Larger pump room (72)
The fluid flows to Then, in the pump chambers (72) of the reciprocating pumps (60a, b, c) whose connection relationship is adjacent to each other, the movement of the reciprocating members (63, 86) of the reciprocating pumps (60a, b, c) on the discharge port side. The rotation angle range A1 whose speed is higher than the moving speed of the reciprocating members (63, 86) of the reciprocating pumps (60a, b, c) on the suction side (hereinafter, all rotation angles are considered to be the rotation angle of the drive shaft (24). ) Indicates that the moving speed of the reciprocating member (63, 86) of the reciprocating pump (60a, b, c) on the discharge port side is equal to that of the reciprocating member (63, 86) of the reciprocating pump (60a, b, c) on the suction port side. It is equal to the rotation angle range A2 smaller than the moving speed (A1 = A2), that is, A1 = A2 = 180 °. But the connection passage
(73) is a reciprocating member (6) of the reciprocating pumps (60a, b, c) at both ends.
(86) The reciprocating member in the rotation angle range including the top dead center
(63,86), the closing period C is A2
In other words, since the fluid flow has a rotation angle range in which the flow of the fluid flows backward from the pump chamber (72) on the discharge port side to the pump chamber (72) on the suction port side, the connection passage (73) While communicating with the pump chamber (72) of the reciprocating pump (60a, b, c),
The moving speed of the reciprocating member (63, 86) of the reciprocating pump (60a, b, c) on the discharge port side is the same as the reciprocating member (6) of the reciprocating pump (60a, b, c) on the suction port side.
The rotation angle range B1, which is larger than the moving speed of the reciprocating pump (60a, b, c) on the discharge port side (63, 86), is maintained equal to A1, that is, 180 °. ) Is the reciprocating member (63,86) of the reciprocating pump (60a, b, c) on the suction port side
B2 = A2-
C, that is, B2 <180 °. Thus, when the pump chamber (72) of the reciprocating pump (60a, b, c) on the suction port side is set to the forward direction from the pump chamber (72) of the reciprocating pump (60a, b, c) on the discharge port side, the forward direction The rotation angle range B1 of the flow becomes longer than the rotation angle range B2 of the flow in the opposite direction (B1> B2),
Fluid flows as a whole in the reciprocating pump device (55, 85), that is, from the suction port (70) to the discharge port (71).

In the reciprocating pump device (55, 85), the reciprocating pump device (55, 85) can be formed without using any check valve type suction valve and discharge valve. , 8
The structure 5) can be simplified and downsized.

According to the reciprocating pump device (55, 85) of the present invention, each reciprocating pump (60a, b, c) is closed when the pump chamber (72) is sealed by the reciprocating members (63, 86). Equipped with pressure relief passages (79, 91) for pressure relief.

When the fluid sucked and discharged by the reciprocating pump device (55, 85) is an incompressible positive fluid, that is, a liquid, in each reciprocating pump (60a, b, c), the reciprocating member (63, 86) When the reciprocating pump related to the reciprocating member (63, 86) is the reciprocating pump (60a) at one end of the series connection) the suction port (70) and the connection passage (73)
(If the reciprocating pump according to the reciprocating member (63, 86) is an intermediate reciprocating pump (60b) in series connection), the two connecting passages (73) Reciprocating pump
When the connection passage (73) and the discharge port (71) are closed and sealed, the operation of the reciprocating pumps (60a, b, c) is hindered. The pressure relief passage (79, 91) discharges liquid from the pump chamber (72) at such time, and ensures smooth operation of the reciprocating pumps (60a, b, c). When the fluid sucked and discharged by the reciprocating pump device (55, 85) is a compressive fluid, the pressure relief passage (79, 91) is unnecessary.

According to the reciprocating pump device (55, 85) of the present invention, the pressure relief passage (79, 91) is formed on the circumferential surface of the cylinder member (76) by the groove extending in the axial direction of the reciprocating member (63, 86). (79), and the groove (79) has a crosshead pin (6) rotatably connecting the reciprocating member (63, 86) and the connecting rod (25).
It is located at a position apart from the direction (78) perpendicular to the axial direction (77) in the circumferential direction by α (0 ° <α <90 °) in the circumferential direction.

The reciprocating member (63, 86) extends from the connecting rod (25) at right angles to the axial direction (77) of the crosshead pin (62).
It receives a load in the direction of (78) and is pressed against the peripheral surface of the cylinder member (76). If the groove (79) is the crosshead pin (62)
If it is arranged in a direction (78) perpendicular to the axial direction (77), the groove (79) is pressed against the reciprocating members (63, 86), and stress concentration causes abnormal friction and heat generation. However, the groove (7
9) is shifted by α from the direction (78) perpendicular to the axial direction (77) of the crosshead pin (62), so that the reciprocating member (63, 86) can smoothly move the cylinder without causing such a problem. It can move within the member (76).

According to the reciprocating pump device (55, 85) of the present invention, the reciprocating pump device (55, 85) is replaced with the sub reciprocating pump device (55, 85).
The sub reciprocating pump device (55,85) is replaced by the main reciprocating pump device (1
0) is disposed on the drive shaft case (11), and the sub reciprocating pump device (5
Each reciprocating member (63, 86) of the main reciprocating pump device (10) also serves as a crosshead (63, 86) of the reciprocating member (28) of the main reciprocating pump device (10), and the suction port (7, 85).
0), discharge port (71), and connection passage (73)
The drive shaft case (11) of (10) is formed.

Each reciprocating pump of the sub reciprocating pump device (55, 85)
(60a, b, c) are each reciprocating pump (1) of the main reciprocating pump device (10).
The reciprocating pump device (55) is provided in the range of the crosshead (63, 86) of the reciprocating member (28) of (8) and is disposed in the drive shaft case (11) of the main reciprocating pump device (10). , 85) and the entire main reciprocating pump device (10) can be greatly reduced in size.

According to the reciprocating pump device (55, 85) of the present invention, the sub reciprocating pump device (55, 85) is
This is an oil pump that sucks and discharges oil in the drive shaft case (11).

The sub reciprocating pump device (55, 85) is disposed in the drive shaft case (11) of the main reciprocating pump device (10), and is used as an oil pump to reduce the size and structure of the oil pump. Can be simplified. In particular, when both the main reciprocating pump device (10) and the sub reciprocating pump device (55, 85) are applied as a multiple pump device, the entire sub reciprocating pump device (55, 85) is used as the main reciprocating pump device (10). The space efficiency is increased by arranging in the common drive shaft case (11) and using it as an oil pump for sucking and discharging oil in the drive shaft case (11).

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram of a main triple piston pump device 10. Crankcase 11, suction manifold 12, cylinder pipe 13, and discharge manifold 14
Are sequentially arranged in a horizontal direction perpendicular to the horizontal axis direction of the crankshaft 24 and are joined to each other. The main triple piston pump device 10 is composed of a total of three piston pumps 18. The cylinder pipes 13 are provided for each piston pump 18 and are arranged in a line in the axial direction of the crankshaft 24. One suction port 19 is provided below the suction manifold 12, and communicates with a suction chamber 20 in the suction manifold 12. One discharge port 21 is provided above the discharge manifold 14 and communicates with a discharge chamber 22 in the discharge manifold 14. The crankshaft 24 passes through the crankcase 11 in the horizontal direction, and each piston pump 18 is connected to a common crankshaft 24 by a connecting rod 25 rotatably coupled to a crankpin at a different position in the axial direction on the proximal end side, and a crankshaft. Case 11,
It has a suction manifold 12 and a piston rod 28 extending along the center line in the cylinder pipe 13. The three piston pumps 18 are operated with a phase difference of 120 ° (hereinafter, the phase of the pump is defined by the rotation angle of the crankshaft 24) in the order of operation. The seal packing 29 is disposed on the base end side of the suction manifold 12 and slidably contacts the piston rod 28 on the inner peripheral side, and the crankcase 11 and the suction manifold
Seal between 12. The valve element 33 and the stopper 34 are attached to the distal end of the piston rod 28 at predetermined intervals in a relation of the base end side and the distal end side, respectively, and the nut 35 is screwed into the piston rod 28 from the distal end side of the stopper 34. And stopper
The valve body 34 and the valve body 33 are tightened toward the base end side to fix them. The valve seat 40 is loosely fitted to the piston rod 28 between the valve body 33 and the stopper 34, and the piston packing 41
The outer peripheral side of the cylinder 40 is fitted to the valve seat 40, and the outer peripheral side is in sliding contact with the inner periphery of the cylinder pipe 13, thereby sealing between the inner periphery of the cylinder pipe 13 and the valve seat 40. The valve body 33 and the valve seat 40 constitute an intake valve. The pump chamber 36 is formed on the cylinder pipe 13 on the tip side of the stopper 34, and is provided with a discharge valve.
44 is provided between the pump chamber 36 and the discharge chamber 22. In the suction stroke, the discharge valve 44 is closed, the valve seat 40 contacts the stopper 34, and the liquid in the suction chamber 20 is discharged from the outside of the valve body 33 to the piston rod 28.
The fluid flows into the pump chamber 36 through an annular space between the valve seat 40 and the valve seat 40 and a through hole (not shown) of the stopper 34. In the discharge stroke, the discharge valve 44 is opened, the valve seat 40 comes into contact with the valve body 33, and the communication between the suction chamber 20 and the pump chamber 36 is cut off.
The liquid in 36 is discharged to the discharge chamber 22 via the discharge valve 44. Felt material 47 comes from seal packing 29 to crankcase 11
On the side of the piston rod 28, the oil case 48
The oil inside is penetrated by capillary action, and the piston rod 28
Adhere to

FIG. 2 is a diagram showing the configuration inside the crankcase 11 of the main triple piston pump device 10. The auxiliary triple plunger pump device 55 is provided in the crankcase 11, and includes three auxiliary reciprocating pumps 60a, 60b, 60c. Both ends of the crankshaft 24 are rotatably supported on the side wall of the crankcase 11 by ball bearings 56. The sub reciprocating pumps 60a, b, c
They are arranged sequentially in the axial direction of the crankshaft 24 and have the same structure. In the crankcase 11, each sub reciprocating pump
A cylindrical hole 76 is formed for each of the cylinder holes 60a, 60b, 60c, and the crosshead 63 is slidably accommodated in each cylindrical hole 76. The crosshead 63 has a plunger 64 rotatably coupled to the distal end of the connecting rod 25 via a crosshead pin 62 at a proximal end.
And a small-diameter portion 65 on the distal end side of the plunger 64.
66 is formed in the small diameter portion 65 along the center line of the small diameter portion 65 from the distal end surface of the small diameter portion 65, and the base end of the piston rod 28 (FIG. 1) is screwed into the small diameter portion 65. Thus, the piston rod 28 reciprocates integrally with the crosshead 63 and reciprocates stabilized by the guidance of the crosshead 63 in the cylindrical hole 76.
The oil seal 67 is fitted into the stepped portion in the crankcase 11, and slides on the small diameter portion 65 on the inner peripheral side to seal the cylindrical hole. The suction port 70 is a sub reciprocating pump of the crankcase 11
The cylindrical hole 76 of the sub reciprocating pump 60a is bored in the side wall on the 60a side and communicates with the outside of the crankcase 11. Discharge port 71
Is formed in the side wall of the crankcase 11 on the side of the sub reciprocating pump 60c, and the cylindrical hole 76 of the sub reciprocating pump 60c is
1 is connected to the outside. Two communication holes 73 are formed in the crankcase 11, and one communication hole 73 is a sub reciprocating pump.
The cylindrical hole 76 of the sub-reciprocating pump 60b communicates with the cylindrical hole 76 of the sub-reciprocating pump 60b.
6 and the cylindrical hole 76 of the sub reciprocating pump 60c communicate with each other. In the cylindrical hole 76, a pump chamber 72 is formed between the oil seal 67 and the step on the tip end side of the plunger 64. The sub reciprocating pumps 60a, b, and c are the corresponding piston pumps 18 (FIG. 1).
Since they are integrally operated, they are operated in the same order as the corresponding piston pumps 18 and are adjacent to each other in the operation order (in this embodiment, the sub-reciprocating pumps 60a, b, and c are operated in the order of
Driving order = array order. The reciprocating pump before ()) is ahead of the reciprocating pump by 120 ° in phase. The suction port 70, the discharge port 71, and the communication hole 73 are closed by the plunger 64 in a rotation angle range of ± 30 ° including the top dead center, in which the plunger 64 of the sub reciprocating pumps 60a, b, and c with which the The other rotation angle ranges are the positions and dimensions that open to the pump chamber 72. In FIG. 2, the suction port 70 and the discharge port 71
Although the connection destination is not shown, for example, this sub-triple plunger pump device 55 is used as an oil pump of the main triple piston pump device 10, and the suction port 70 is located at the lower part in the crankcase 11, and the discharge port is 71 is an oil cooler (not shown)
And the oil may be circulated in an oil passage including the inside of the crankcase 11 and the oil cooler to prevent overheating of the oil.

Although the illustrated crankshaft 24 is disposed horizontally, when the crankshaft 24 is disposed vertically, it is connected so that oil from the discharge port 71 is supplied to the upper ball bearing 56, The upper ball bearing 56 can be lubricated without filling the case 11 with oil up to the upper end.

FIG. 3 is a cross-sectional view of the sub reciprocating pump 60a of FIG. 2 in which the cylindrical hole 76 is cut at an axial position on the proximal side from the suction port 70. The center line 77 coincides with a direction parallel to the axial direction of the crankshaft 24. The direction parallel to the axial direction of the crankshaft 24 is also the center line direction of the suction port 70, the discharge port 71, and the communication hole 73. The center line 78 is a cylindrical hole 76
And the center line 77 (the perpendicular direction coincides with the vertical direction in FIG. 1). The pair of hydraulic pressure relief grooves 79 are located symmetrically with respect to the center of the cylindrical hole 76, and at a position shifted by 30 ° in the circumferential direction of the cylindrical hole 76 with respect to the center line 78, the axis of the cylindrical hole 76 is formed. The pump chamber 72 extends in the direction from the pump chamber 72 to the base end of the cylindrical hole 76, and connects the pump chamber 72 to the movement space of the connecting rod 25.

The sub reciprocating pumps 60a, 60b and 60c are operated with the phase delayed by 120 ° in this order in accordance with the rotation of the crankshaft 24. The crosshead 63 reciprocates with the rotation of the crankshaft 24 to increase or decrease the volume of the pump chamber 72.
The moving speed Vp of the plunger 64 of the sub reciprocating pump 60a is expressed by the following equation. Vp = Vc · {sin θ + (R · sin 2θ) / (2 · L)} (1) where θ: angle of crankshaft 24, L: length of connecting rod 25, R: length of crank arm, Vc: Crosshead
63 maximum moving speed. In (1), L / R = 6.7.
, That is, L >> R.

FIG. 4 shows Vp / Vc of the sub reciprocating pumps 60a, 60b, 60c.
And the relationship between the rotation angle of the crankshaft 24 and the pressure state between the sub reciprocating pumps. In FIG. 4, Vp / V
c is the following (2) which approximates the expression (1), as L >> R.
It is represented by an equation. Vp = Vc · sin θ (2) In FIG. 4, # 1, # 2, and # 3 denote sub reciprocating pumps 60a, b, and c, respectively, and .largecircle. The flow from the outlet to the outlet 71 is defined as a forward direction, and the flow from the outlet 71 to the inlet 70 is defined as a reverse direction.)
Means a pressure state that causes the flow of the reciprocating pump, x indicates a reverse flow between the sub-reciprocating pumps, and-indicates a pump because the suction port 70, the discharge port 71, and the communication hole 73 of the reciprocating pump are closed by the plunger 64. This shows a state in which the chamber 72 is in a sealed state and no liquid flows in and out of the pump chamber 72. For example, the plunger 6 of the sub reciprocating pump 60a is
4 closes the inlet 70 (0 ° ≦ θ ≦ 30
°, 330 ° ≤ θ ≤ 360 °), the flow of liquid into and out of the pump chamber 72 of the sub-reciprocating pump 60a outside the sub triple reciprocating pump 60a via the suction port 70 is stopped, and the cylinder of the sub reciprocating pump 60a Hole 76-communicating hole of cylindrical hole 76 of sub reciprocating pump 60b
About 73, when the plunger 64 of the sub reciprocating pump 60a closes the corresponding communication hole 73 (0 ° ≦ θ ≦ 30 °,
330 ° ≦ 360 °) and when the plunger 64 of the sub reciprocating pump 60b closes the corresponding communication hole 73 (90 °).
≤ θ ≤ 150 °), and the sub reciprocating pump 60
Pumping of the liquid in the pump chamber 72 of the sub-reciprocating pump 60b is stopped. Further, the suction force of each pump chamber 72 is V
Since p / Vc increases as p / Vc increases, adjacent reciprocating pumps move the liquid from the pump chamber 72 having the smaller Vp / Vc to the pump chamber 72 having the larger Vp / Vc. (Forward direction) and x (= reverse direction) are determined. As can be understood from FIG. 4, if the communication hole 73
If is not closed by the plunger 64, the section is set to be x. Therefore, due to the presence of-, the section of x is reduced from the original six, and the flow of liquid from # 1 to # 2,
In each of the flows of liquid from # 2 to # 3, the forward flow section (= ○ section) is six, while the × section is two, and the liquid is # 1 → # Go from 2 to # 3. The suction port 70 → the pump chamber 7 of the sub reciprocating pump 60a
With respect to the entry and exit of the liquid from the pump chamber 72 to the discharge port 71 of the sub reciprocating pump 60c and the sub reciprocating pump 60c, there are five sections in each of the sections of ○ and X, and the subtraction is 0, and the substantial flow of the liquid is Although it does not appear to occur, the amount of liquid flowing into the pump chamber 72 of the sub reciprocating pump 60a from outside the sub triple plunger pump device 55 at the suction port 70 due to the inertia of the flow in # 1 → # 2 → # 3. Is larger than the reverse, and the outlet 71
In the case, the amount of liquid flowing out of the sub triple plunger pump device 55 from the pump chamber 72 of the sub reciprocating pump 60c is larger than the reverse. In this manner, the sub-triple plunger pump device 55 sucks the liquid from the suction port 70 and discharges the liquid from the pump chamber 72. In the sub reciprocating pumps 60a, 60b and 60c, when each plunger 64 has a rotation angle of ± 30 ° with respect to the top dead center, each pump chamber 72 is in a sealed state, and the liquid is incompressible. If the inside of the pump chamber 72 is sealed, the movement of the plunger 64 is hindered. However, when the pump chambers 72 are sealed, the hydraulic pressure relief grooves 79 connect the pump chambers 72 with the connecting rods 25.
Is connected to the space inside the crankcase 11
The sealed liquid is released via the hydraulic pressure release groove 79,
A situation in which the plunger 64 stops exercising can be prevented.

FIG. 5 is a structural view in the case where the sub triple piston pump device 85 is installed in the crankcase 11 of the main triple piston pump device 10. The same elements as those in FIG. 2 are designated by the same reference numerals, and only different points will be described. Each sub reciprocating pump 60a, b, c
, The axial direction of the crosshead pin 62 is
Parallel to the axial direction of the piston and crosshead
The connecting rod 86 is rotatable around the axis of the crosshead pin 62 at the base end via the crosshead pin 62.
And slidingly contact the cylindrical hole 76. The connecting rod 88 is
The base end is a screw hole 92 at the tip of the piston and crosshead 86.
, And penetrates while sliding on the oil seal 67. The connecting rod 88 has a screw hole 66 at the distal end, and the proximal end of the piston rod 28 (FIG. 1) is screwed into the screw hole 66. Pump room 72
Is formed between the oil seal 67 and the distal end surface of the piston / crosshead 86 in the axial direction of the connecting rod 88, and the volume is increased or decreased as the piston / crosshead 86 reciprocates. The positions of the suction port 70, the discharge port 71, and the communication hole 73 are the same as those in the case of the sub-triple plunger pump device 55, and the corresponding piston / crosshead 86 is within ± 30 ° of the top dead center. At one time, communication with the corresponding pump chamber 72 is cut off by the periphery of the piston / crosshead 86. Also in this sub-triple piston pump device 85, the crankshaft 24
With the operation, the liquid flows from the suction port 70 to the discharge port 71.

FIG. 6 is a cross-sectional view of the piston / crosshead 86 of FIG. Sub-Triple Plunger Pump Device 55 of FIG.
, A hydraulic pressure relief groove 79 is formed on the inner periphery of the cylindrical hole 76. However, in the sub-triple piston pump device 85, the hydraulic pressure relief groove 79 is not provided, and instead, a pair of hydraulic pressure relief grooves 79 are provided. An escape through hole 91 is formed in the piston / crosshead 86 at a position symmetrical with respect to the center of the screw hole 92 of the connecting rod 88 so as to pass through the piston / crosshead 86 in the axial direction. Thus, even when the communication hole 73 and the like are closed by the piston / crosshead 86 and the pump chamber 72 is sealed, the pump chamber 72 is closed.
The liquid inside is released via the hydraulic pressure release hole 91, and the sub-triple piston pump device 85 is operated without any trouble.

If the crankshaft 24 is rotated in the reverse direction,
Vp / Vc characteristics are upside down, and the order of # 3, # 2, and # 1 is from the earliest phase. As a result, the liquid flows in the direction opposite to that in the forward rotation, that is, is sucked from the discharge port 71, and is discharged from the suction port 70 through the sub reciprocating pumps 60c, b, and a in order.

[Brief description of the drawings]

FIG. 1 is a schematic view of a main triple piston pump device.

FIG. 2 is a configuration diagram of the inside of a crankcase of the main triple piston pump device.

FIG. 3 is a cross-sectional view of the sub reciprocating pump of FIG. 2 in which a cylindrical hole is cut at an axial position closer to a base end side than a suction port.

FIG. 4 is a diagram showing a relationship between Vp / Vc of a sub reciprocating pump and a rotation angle of a crankshaft, and a pressure state between the sub reciprocating pumps.

FIG. 5 is a structural view when the sub-triple piston pump device is provided in a crankcase of the main triple piston pump device.

FIG. 6 is a cross-sectional view of the piston / crosshead of FIG. 5;

[Explanation of symbols]

Reference Signs List 10 main triple piston pump device (main reciprocating pump device) 11 crankcase (drive shaft case) 18 piston pump (main reciprocating pump) 24 crankshaft (drive shaft) 25 connecting rod 28 piston rod (reciprocating member) 55 sub triple plunger Pump device (reciprocating pump device, sub reciprocating pump device, oil pump) 60 sub reciprocating pump (reciprocating pump) 62 crosshead pin 63 crosshead (reciprocating member) 70 suction port 71 discharge port 72 pump chamber 73 connection passage (communication hole) 76 Cylindrical hole (cylinder member) 79 Hydraulic relief groove (pressure relief passage) 85 Secondary triple piston pump device (reciprocating pump device,
Sub-reciprocating pump device) 86 Piston and crosshead (reciprocating member, crosshead) 91 Through-hole for hydraulic pressure relief (pressure relief passage)

Claims (5)

[Claims] A reciprocating pump device in which a plurality of reciprocating pumps (60a, b, c) are connected in series with their pump chambers (72) and are operated by a common or separate drive shaft (24). (Five
(5, 85), each reciprocating pump (60a, b, c) reciprocates in the cylinder member (76) by the drive of the drive shaft (24).
6) Reciprocating member (63,86) for increasing or decreasing the volume of pump chamber (72)
The reciprocating pumps (60a, b, c) at one end and the other end of the series connection have a suction port (70) and a discharge port (71) as a whole reciprocating pump device (55, 85), respectively. The adjacent reciprocating pumps (60a, b, c) have their cylinder members (76) connected to each other by a connection passage (73), and the connection passage (73) and the pump chamber (7) are connected to each other.
With the reciprocating members (63, 86), the communication with the reciprocating members (63, 86) is established by the reciprocating members (63, 86). , The reciprocating pump (60a, b, c) on the suction port side is more θ than the reciprocating pump (60a, b, c) on the discharge port side (0 ° <θ <180 °)
The connection passage (73), which is operated in the advanced phase and communicates with the cylinder member (76) of the double reciprocating pump (60a, b, c), is a double reciprocating pump.
It is closed in a predetermined rotation angle range including the top dead center of the reciprocating member (63, 86) of (60a, b, c) (the rotation angle is defined by the rotation angle of the drive shaft (24)). A reciprocating pump device characterized in that the position is set as described above. 2. The reciprocating pump (60a, b, c) has a pressure relief passage (79, 91) for releasing pressure when the pump chamber (72) is sealed by the reciprocating member (63, 86). 2. The reciprocating pump device according to claim 1, further comprising: 3. The pressure relief passage (79, 91) is formed as a groove (79) extending in the axial direction of the reciprocating member (63, 86) on the peripheral surface of the cylinder member (76). ) Is α from the direction (78) perpendicular to the axial direction (77) of the crosshead pin (62) rotatably connecting the reciprocating members (63, 86) and the connecting rod (25) (0 ° <α). The reciprocating pump device according to claim 2, wherein the pump device is located at a position apart in the circumferential direction by <90 °). 4. The reciprocating pump device (55, 85) is a sub reciprocating pump device (55, 85), and the sub reciprocating pump device (55, 85) is a drive shaft case of the main reciprocating pump device (10). 11), each reciprocating member (63, 86) of the sub reciprocating pump device (55, 85)
Serves also as a crosshead (63, 86) of each reciprocating member (28) of the main reciprocating pump device (10), the suction port (70) and the discharge port (7
1), and the connection passage (73) is the main reciprocating pump device (10)
The reciprocating pump device according to any one of claims 1 to 3, wherein the reciprocating pump device is formed on the drive shaft case (11). 5. The sub reciprocating pump device (55, 85) is an oil pump that sucks and discharges oil in a drive shaft case (11) of the main reciprocating pump device (10). Item 6. A reciprocating pump device according to Item 4.