JP2001280234A - Opposed type reciprocating pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the vibration of a reciprocating pump having two cylinders. SOLUTION: The horizontally opposed type reciprocating pump 10 comprises con'rods 15A, 15B in the same shape connected to two eccentric pins 14A, 14B, respectively, provided on a driving shaft 13 of a motor 12, and pistons 18A, 18B in the same shape joined to the con'rods 15A, 15B and adapted to be reciprocably moved to be opposed to the cylinders 17A, 17B, respectively, with the reciprocating phase of both pistons 18A, 18B coaxially shifted 180 degrees to each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an opposed reciprocating pump used as a compressor or a vacuum pump.

[0002]

2. Description of the Related Art In a conventional reciprocating pump having two cylinders, a piston is connected via a connecting rod to each of two drive shafts projecting to both sides of a motor, and one piston is connected to one of the two drive shafts. In this cylinder, the other piston is provided in the other cylinder so as to be reciprocally movable, and both pistons are reciprocated by giving a phase difference of 180 degrees.

[0003]

However, in the prior art, even if the phase of the reciprocating motion of both pistons is shifted by 180 degrees to cancel the inertial mass of the linear motion, the reciprocating motion of both pistons is not coaxial. The inertial forces of both pistons create a moment about the center of the motor, which causes the reciprocating pump to vibrate significantly.

An object of the present invention is to reduce vibration of a reciprocating pump having two cylinders.

[0005]

According to a first aspect of the present invention, there is provided an opposed reciprocating pump according to the present invention, wherein two eccentric portions are juxtaposed on a drive shaft of a motor fixed to a housing, and each of the two eccentric portions is provided separately. Are connected to each other, and two cylinders opposed to each other on both sides of the drive shaft are fixed to the housing so as to be coaxially symmetrically arranged. A piston having the same shape coupled to each connecting rod is connected to each cylinder. Reciprocating freely, and the phase of the reciprocating motion of both pistons on the same axis
It is designed to move 180 degrees to face each other.

According to a second aspect of the present invention, in the first aspect of the present invention, a plurality of sets of the piston and the cylinder corresponding to a pump flow rate are prepared, and each piston is replaced with a connecting rod. In addition to being freely movable, each cylinder is made freely replaceable with respect to the housing.

According to a third aspect of the present invention, in the first or second aspect of the present invention, a bearing is interposed between the eccentric portion of the drive shaft and the connecting portion of the connecting rod, and the bearing is provided on the connecting rod. To be fixed by crimping in the fitting hole

[0008]

According to the first aspect of the present invention, the following operations are provided. Two reciprocating pumps are opposed to each other, and two pistons reciprocating inside two cylinders make the phase difference of the reciprocating motion 180 degrees coaxially, and both pistons have the same shape and are connected to both pistons The connecting rods have the same shape.
For this reason, the inertial forces of the reciprocating motion of both pistons are completely canceled each other, and vibration can be reduced.

The drive shaft of the motor is a single shaft protruding only on one side of the motor, two eccentric portions are juxtaposed at two positions adjacent to the single shaft, and a connecting rod is connected to each of the two eccentric portions. According to this, the motor can be simplified and the cost can be reduced as compared with the case where a double-axis motor is used.

According to the second aspect of the present invention, the following effects are obtained. Prepare a set of pistons and cylinders corresponding to the pump flow rate, replace each piston for the connecting rod, and replace each cylinder for the housing to reciprocate with the piston and cylinder corresponding to the desired flow rate. The pump can be easily realized, and the flow rate can be easily adjusted.

According to the third aspect of the invention, the following operation is provided. Since the bearing is fixed to the fitting hole of the connecting rod by caulking, it has better workability, has no variation in fixing strength, and has an adhesive inside the bearing, compared to the one that uses an adhesive to fix it. There is an advantage that there is no hindrance of the rotation of the bearing due to the inflow of water, and there is no waiting for the curing time of the adhesive, so that the productivity is good.

[0012]

1 is a sectional view showing a horizontally opposed reciprocating pump, FIG. 2 is a perspective view showing a drive shaft, a connecting rod and a piston, and FIG. 3 is a perspective view showing an exploded state of a piston and a cylinder. 4 is a perspective view showing a configuration of a piston, FIG. 5 is a perspective view showing a connecting rod and a bearing, and FIG. 6 is a sectional view showing a caulking device of the bearing.

As shown in FIG. 1, a horizontally opposed reciprocating pump 10 has a motor 12 fixed to a housing 11 and two eccentric pins (eccentric portions) at two positions adjacent to a drive shaft 13 projecting to one side of the motor 12. ) 14A, 14B are arranged side by side in a state of being fixed by set screws, and both eccentric pins 14A, 14B
L-shaped connecting rods 15A, 15A,
5B (FIG. 2). Eccentric pins 14A, 14B
Are eccentrically arranged with respect to the drive shaft 13. The connecting rods 15A, 15B are connected to eccentric pins 14A, 14B of the drive shaft 13 via bearings 16A, 16B.

The horizontally opposed reciprocating pump 10 includes a drive shaft 1
, Two opposite cylinders 17A, 17
B such that the cylinders 17
A and 17B are fixed to the housing 11 by bolts 18 (FIG. 3).

The horizontally opposed reciprocating pump 10 has a piston 1 having the same shape on each of the connecting rods 15A and 15B.
8A and 18B are connected. At this time, each piston 1
8A and 18B are between the ring pressers 19A and 19B,
Piston ring 20 slidingly contacting cylinders 17A and 17B
A is attached to connecting rods 15A and 15B by bolts 21 with A and 20B sandwiched (FIG. 4). The reciprocating pump 10 reciprocates the pistons 18A and 18B to the cylinders 17A and 17B, respectively, and moves the pistons 18A and 18B to face each other with the phase of the reciprocating motion shifted 180 degrees coaxially.

The horizontally opposed reciprocating pump 10 includes a cylinder head 22A, a cylinder head 22A, and a cylinder head 22A, respectively.
22B is attached. Each cylinder head 22A (22
B also includes a suction chamber 23 and a discharge chamber 24, an intake inlet 23 A in the suction chamber 23, and an air inlet 24 A in the discharge chamber 24.
Is provided. Each cylinder head 22A (the same applies to 22B) includes a suction hole 23B that connects the suction chamber 23 to the cylinder 17A and a suction valve 23C thereof, and the discharge chamber 2A.
4 is provided with a discharge hole 24B communicating with the cylinder 17A and a discharge valve 24C thereof.

Therefore, in the horizontally opposed reciprocating pump 10, when the power switch is turned on and the motor 12 is operated, the two pistons 18A and 18B coaxially move through the opposed cylinders 17A and 17B by 180 degrees. It moves horizontally with a phase difference. And the pistons 18A, 18B
During the forward movement (suction stroke), the pressure inside the cylinders 17A and 17B becomes negative, the suction valve 23C opens, and the air is sucked from the suction chamber 23 into the cylinder 17A. On the other hand, when the pistons 18A and 18B move backward (discharge stroke), the insides of the cylinders 17A and 17B are compressed, the discharge valve 24C opens, and the compressed air inside the cylinders 17A and 17B is discharged to the discharge chamber 24. Thereby, in the reciprocating pump 10, the device connected to the suction inlet 23A of the suction chamber 23 is set to a negative pressure, and functions as a vacuum pump. The reciprocating pump 10 supplies compressed air to equipment connected to the air supply port 24A of the discharge chamber 24, and functions as a compressor.

In this embodiment, the pistons 18A, 1
A plurality of sets of 8B and cylinders 17A and 17B corresponding to the pump flow rate (piston diameter × stroke) are prepared.
Connect each piston 18A, 18B to a connecting rod 15A, 15B.
To each cylinder 17A,
By making the housing 17B freely replaceable with respect to the housing 11, the pump flow rate can be adjusted.

In this embodiment, the bearings 16A, 16B interposed between the eccentric pins 14A, 14B of the drive shaft 13 and the connecting portions of the connecting rods 15A, 15B are fitted to the connecting rods 15A, 15B. It is caulked and fixed in the hole 25. 5 and 6, reference numeral 31 denotes a lower caulking jig,
Reference numeral 32 denotes an upper caulking jig, and a central axis 31 of the lower caulking jig 31.
A connecting rod 15A (15B) is arranged around A, and a bearing 16A (16B) is fitted into its central axis 31A.
The bearing 16A (16B) is connected to the connecting rod 15A (15
After fitting into the fitting hole 25 of (B), the claw 32A which is fitted into the center shaft 31A and which extends over the entire circumference of the upper caulking jig 32 is pressed against the entire periphery of the fitting hole 25 of the connecting rod 15A (15B). , Bearing 16A (16B) connecting rod 1
The entire circumference is crimped and fixed in the fitting hole 25 of 5A (15B).

According to this embodiment, the following operations are provided. Two reciprocating pumps 10 are horizontally opposed, and two pistons 18 reciprocate inside two cylinders 17A and 17B.
A and 18B adjust the phase difference between their reciprocating motions by 180
And connecting rods 15A connected to both pistons 18A and 18B,
15B have the same shape. Therefore, both pistons 1
The inertial forces of the reciprocating motions of 8A and 18B completely cancel each other, and vibration can be reduced.

The drive shaft 13 of the motor 12 is
The two eccentric pins 14A and 14B are arranged side by side at two positions adjacent to the one shaft so that the two eccentric pins 14A and 14B are arranged side by side.
Can be connected to the connecting rods 15A and 15B, respectively, and according to this, the motor 12 can be simplified and the cost can be reduced as compared with the case where a double-axis motor is used.

The pistons 18A and 18B and the cylinder 17
A set of A and 17B corresponding to the pump flow rate is prepared, each piston 18A and 18B is exchanged for the connecting rods 15A and 15B, and each cylinder 17A and 17B is exchanged for the housing 11 to obtain a desired flow rate. The reciprocating pump 10 having the pistons 18A, 18B and the cylinders 17A, 17B corresponding to the above can be easily realized, and the flow rate can be easily adjusted.

Fitting hole 25 for connecting rods 15A, 15B
Since the bearings 16A and 16B are fixed by caulking, the workability is better and the fixing strength does not vary as compared with the case where the bearings 16A and 16B are fixed using an adhesive.
6A, 16B due to the flow of the adhesive into the bearing 16
There are merits such as no inhibition of rotation of A and 16B and good productivity because there is no waiting for the curing time of the adhesive.

Although the embodiment of the present invention has been described in detail with reference to the drawings, the specific structure of the present invention is not limited to this embodiment, and two cylinders are vertically opposed. The present invention includes any design change or the like within a range not departing from the gist of the present invention.

[0025]

As described above, according to the present invention, the vibration of the reciprocating pump having two cylinders can be reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a horizontally opposed reciprocating pump.

FIG. 2 is a perspective view showing a drive shaft, a connecting rod, and a piston.

FIG. 3 is a perspective view showing a disassembled state of a piston and a cylinder.

FIG. 4 is a perspective view showing a configuration of a piston.

FIG. 5 is a perspective view showing a connecting rod and a bearing.

FIG. 6 is a sectional view showing a bearing caulking device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Horizontally opposed reciprocating pump 11 Housing 12 Motor 13 Drive shaft 14A, 14B Eccentric pin (eccentric part) 15A, 15B Connecting rod 16A, 16B Bearing 17A, 17B Cylinder 18A, 18B Piston 25 Fitting hole

Claims (3)

[Claims] 1. Two eccentric portions are provided side by side on a drive shaft of a motor fixed to a housing, and connecting rods having the same shape are connected to each of the eccentric portions, and two eccentric portions are opposed to each other on both sides of the drive shaft. The cylinders are fixed to the housing so as to be arranged symmetrically on the same axis, the pistons of the same shape connected to each connecting rod are reciprocally movable in each of the cylinders, and the phase of the reciprocating movement of both pistons is 180 ° on the same axis. Opposite reciprocating pumps that move oppositely with a stagger. 2. A plurality of pairs of pistons and cylinders corresponding to pump flow rates are prepared, and each piston is freely exchangeable with a connecting rod, and each cylinder is freely exchangeable with a housing. The opposed reciprocating pump described. 3. The opposed reciprocating method according to claim 1, wherein a bearing is interposed between the eccentric portion of the drive shaft and the connecting portion of the connecting rod, and the bearing is crimped and fixed to a fitting hole provided in the connecting rod. Dynamic pump.