JP2001107844A - Reciprocating pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a fluid leak in a valve-less reciprocating pump. SOLUTION: This reciprocating pump, provided with a body having a suction port and a delivery port formed in a different position in an axial line direction relating to this suction port, cylinder provided capable of reciprocation sliding along an axial line direction of the body in its inside, and a piston having a central part formed capable of reciprocation sliding in the cylinder and a tip head part formed so as to make a pump chamber with an inner surface of the cylinder, has a first/second through hole in the cylinder, to be formed capable of reciprocation so as to connect the pump chamber and the suction port by the first communication hole at suction time and so as to connect the pump chamber and the delivery port by the second through hole at delivery time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reciprocating pump, and more specifically to a reciprocating pump capable of sending a liquid without using a check valve, and having a high volumetric efficiency and suitable for a liquid which easily generates gas. It relates to a reciprocating pump that can be used.

[0002]

2. Description of the Related Art As a reciprocating pump having no check valve, for example, a reciprocating pump described in JP-A-3-260377 has been known.

In the reciprocating pump, the tip of the cylindrical body 4 is formed in a substantially frustoconical shape, and in the circumferential direction of the inclined surface,
As shown in FIG. 13 (b), a long conductive hole 5 is formed.

As shown in FIG. 13A, the cylinder 1 has a cylinder body 1 having a discharge port 3 on a peripheral wall.
A discharge hole 17 communicating with the discharge port 3 is bent and formed at one end of a, a bushing 19 having a suction hole 18 formed in the axial direction is fitted therein, and a guide tube 20 is fitted at the other end thereof. ing. In FIG. 13, reference numeral 2 denotes a suction port.

[0005] An O-ring 21 is mounted in a concave groove provided on one end side of the piston 8. A pin 9 protrudes from a predetermined position of the piston rod 22, and the pin 9
The piston 8 is configured to be fitted into the long grooves 5 and 6 so that the piston 8 rotates together with the cylindrical body 4.

In the reciprocating pump, the piston 8
Reciprocates while rotating together with the cylinder 4, and moves through the conduction hole 5 of the cylinder 4 and the suction port of the bushing 19 or the cylinder body 1.
The pump operation is performed by inserting the discharge port 3a in a face-to-face manner.
In the "Prior Art" and the following "Problems to be Solved by the Invention", the symbols described after each element name are the symbols in JP-A-3-260377.

[0007]

However, since the cylinder 4 rotates with respect to the bushing 19, it is necessary to provide a gap between the tip of the cylinder 4 and the bushing 19. Therefore, at the time of discharge, a part of the liquid discharged from the discharge port 3 may flow backward to the suction port 2 through the gap.

When the cylinder 4 rotates at a constant speed, the conduction hole 5 formed in the cylinder 4 becomes the suction hole 18 in the bushing 19 and the discharge hole 1 in the cylinder body 1a.
7, the communication hole 5 and the suction hole 1
There is a possibility that a delay in opening and closing occurs between the nozzle 8 and the discharge hole 17, and a liquid leak may occur at a start point and an end point of the suction process and the discharge process.

Further, since the cylinder 4 also rotates with respect to the guide tube 20, it is necessary to provide a gap between the cylinder 4 and the guide tube 20. Therefore, there is a possibility that the liquid handled in the pump chamber 16 may leak from the gap at the time of discharge.

[0010] In addition, when the handling liquid is likely to generate gas such as sodium hypochlorite solution, the reciprocating pump is stopped with the piston 8 raised with respect to the cylinder 4 for a long time. When left undisturbed, the gas occupies the pump chamber 16 between the piston 8 and the cylinder 4,
There is a possibility that a so-called gas lock occurs in which the handling liquid cannot be sent even when the reciprocating pump is restarted.

According to the present invention, the liquid can be sent without using a check valve, and further, there is no liquid leakage at the start point and the end point of the backflow and the suction step and the discharge step. It is an object of the present invention to provide a reciprocating pump capable of sending easily handled liquid without any problem.

[0012]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems. (1) A body having a suction port and a discharge port formed at different positions in the axial direction with respect to the suction port. A cylinder provided inside the body so as to be capable of reciprocating sliding along the axial direction of the body,
A piston having a central portion formed to be reciprocally slidable in the cylinder, and a head portion formed to form a pump chamber with the inner surface of the cylinder, and the cylinder is provided inside the cylinder. A first through-passage and a second through-passage communicating between the pump chamber and the outside, and the pump chamber and the suction port communicate with each other through the first through-path during suction, and the pump chamber during discharge. And the discharge port,
(2) a reciprocating pump formed so as to be able to reciprocate so as to communicate with the second through passage.
A body having a suction port and a discharge port formed at different positions in the axial direction with respect to the suction port; a first through path and a second through path communicating between the inside and the outside; A pump chamber is formed by a cylinder provided so as to be capable of reciprocating sliding along the axial direction of the body, a central portion formed so as to be capable of reciprocating sliding in the cylinder, and an inner surface of the cylinder. A piston having a formed head portion, a piston driving means for driving the piston, and when the volume of the pump chamber changes from a decreasing tendency to an increasing tendency by the driving of the piston, the first through passage causes the pump chamber to communicate with the pump chamber. The cylinder is driven so as to communicate with the suction port, and when the volume in the pump chamber changes from an increasing trend to a decreasing trend, the pump chamber communicates with the discharge port through the second through passage. About reciprocating pump characterized by comprising a cylinder drive means for driving the cylinder like. The body accommodates a cylinder therein so as to be capable of reciprocating sliding. In other words, the body is a cylinder accommodation member.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Example 1 The internal structure of the reciprocating pump of Example 1 is shown in FIG. Less than,
The terms “up”, “down”, “up”, “down”, and “up and down” refer to “up”,
"Lower", "upper", "lower", and "vertical direction" are shown.

As shown in FIG. 1, the reciprocating pump of Example 1 includes a plug 8, which has a closed lower end opening and an opened upper end opening, and has a vertically arranged body. 5, a cylinder 4, which is provided so as to be reciprocally slidable inside the body 5, and has a cylinder 4 open at both ends and a cylindrical piston 3 reciprocating in the cylinder 4.

At the upper end of the body 5, an enlarged portion 5a having an inner diameter larger than the inner diameter of the lower end of the body 5 is formed. Therefore, the body 5 has a small inner diameter portion formed on the lower end side and a large inner diameter portion formed on the upper end side and having an inner diameter larger than the small inner diameter portion.

A suction port 1 is provided on a side wall surface near the lower end opening in the small inner diameter portion of the body 5, and a discharge port is provided above the suction port 1, ie, a side wall surface near the enlarged portion 5a in the small inner diameter portion. 2 are provided.

The upper end opening of the body 5, that is, the opening of the enlarged portion 5a, prevents the cylinder 4 and a cam adapter 12 to be described later from getting out of the body 5, and simultaneously moves the cam adapter 12 up and down. A washer member 17 for guiding in the direction is screwed.

The plug 8 has a head 8b screwed into an opening at the lower end of the body 5, a protrusion 8a protruding from one end of the head, a head 8b and a protrusion 8a. And a step 8c formed between them. When the plug 8 is mounted on the lower end opening of the body 5 by screwing the head 8b into the lower end opening of the body 5, the cylinder 4 is slidably fitted to the projecting portion 8a, and The protruding portion 8a is designed so that the inner peripheral surface of the small inner diameter portion of the body 5 and the outer peripheral surface of the cylinder 4 can slide.

As shown in FIG. 1, near the lower end of the cylinder 4, that is, near the end on the side of the plug 8 which is fitted to the protruding portion 8a, there is a through hole communicating between the outside and the inside of the cylinder 4. First through-path 4a and second through-path 4b, which are holes
And are drilled. The first through passage 4a and the second through passage 4b are provided at positions facing each other with the axis of the cylinder 4 interposed therebetween.

Between the end face of the cylinder 4 where the first through passage 4a and the second through passage 4b are provided and the step 8c of the plug 8, the cylinder 4 is moved upward.
In other words, a coil spring S1 biasing in a direction away from the plug 8 is provided so as to wind around the projecting portion 8a.

At the upper end of the cylinder 4, a flange-like portion 4c is formed outward. When the cylinder 4 is loaded into the body 5, the flange-shaped portion 4c is located in the enlarged portion 5a.

As shown in FIG. 1, the piston 3 has a central portion 3b which reciprocally slides inside the cylinder 4.
A leading portion 3a which is a columnar reduced portion facing the plug 8 and formed concentrically with the center portion 3b adjacent to the center portion 3b; and the leading portion sandwiching the center portion 3b. 3a, the central part 3 located on the opposite side
and a cylindrical handle 3c having an outer diameter smaller than b.

A step is formed between the leading portion 3a and the central portion 3b.

The step in the piston 3 and the head 3
A pump chamber P is formed by the peripheral side surface a, the inner peripheral surface of the cylinder 4, and the end surface of the protruding portion 8a of the plug 8.

As shown in FIG. 1, the lower end of a connecting rod 9 is pivotally mounted on the upper end of the handle 3c of the piston 3 by a pin 16.

FIG. 2 shows details of the vicinity of the upper end of the connecting rod 9 in the reciprocating pump of Example 1. As shown in FIG. 2, an outer ring 9b is formed at the upper end of the connecting rod 9, and an eccentric inner ring 9a is formed inside the outer ring 9b.
Are rotatably provided. A crankshaft 15 rotated by a motor 14 is eccentrically fixed to the eccentric inner ring 9a. A pair of cams 10 are fixed to the crankshaft 15 with the eccentric inner ring 9a interposed therebetween. In FIG. 2, c indicates the center of the eccentric inner ring 9a.

As shown in FIG. 1, a cylindrical cam adapter 12 is provided between the cam 10 and the cylinder 4.

At the upper end of the cam adapter 12, which is the end facing the cam 10, a pair of rollers 11 that rotate while contacting the cam 10 are provided. The lower end of the cam adapter 12 abuts on the flange 4c of the cylinder 4 at the lower end.

The cam adapter 12 and the washer-like member 1
7, a coil spring S2 for urging the cam adapter 12 toward the cam 10 is interposed.

In FIG. 1, reference numeral 13 denotes a housing for accommodating the cam 10, the connecting rod 9, and the crankshaft 15.

As shown in FIG. 2, the cam 10 has a radius R from the center of the crankshaft 15 and a central angle of about 1 unit.
A large-diameter semicircular portion 10a of 80 ° and the crankshaft 15
The radius from the center of the large-diameter semicircular portion 10 where r is smaller than R and the central angle is about 180 °.
and a small-diameter semicircular portion 10b adjacent to a. A linear portion 1 is provided between the large-diameter semicircular portion 10a and the small-diameter semicircular portion 10b.
0c and a linear portion 10d are formed. Straight section 10c
The boundary between the straight portion 10d and the large-diameter semicircular portion 10a and the small-diameter semicircular portion 10b is rounded. FIG. 2 shows a state in which the small diameter semicircular portion 10b is in contact with the roller 11 in the vicinity of the linear portion 10d.

FIG. 3 shows the positional relationship between the piston 3, the cylinder 4, and the body 5 when the piston 3 reaches the bottom dead center and completes the discharge, and the piston 3 reaches the top dead center and sucks. FIG. 4 shows the mutual positional relationship when completed.

When the piston 3 reaches the bottom dead center and completes discharge, the cylinder 4 is at the top dead center as shown in FIG. 3, and the second through passage 4 b is in communication with the discharge port 2. On the other hand, the eccentric inner ring 9a, outer ring 9b, cam 10, roller 11,
The cam adapter 12 and the crankshaft 15 have a positional relationship shown in FIG.

When the crankshaft 15 rotates counterclockwise in FIG. 2, the cam 10 also rotates counterclockwise from the positional relationship in FIG. Therefore, first, since the linear portion 10d of the cam 10 comes into contact with the roller 11, and the cam adapter 12 descends toward the bottom dead center, the cylinder 4 is also pushed down by the cam adapter 12. When the cam 10 further rotates counterclockwise, the large diameter semicircular portion 10a comes into contact with the roller 11, so that the cam adapter 12 stops at the bottom dead center. Therefore, the cylinder 4 also stops at the bottom dead center, and the first through passage 4a communicates with the suction port 1.

On the other hand, with the rotation of the crankshaft 15, the piston 3 rises toward the top dead center, so that the handled liquid is sucked into the pump chamber P through the first through passage 4a and the suction port 1. It is.

When the suction is completed and the piston 3, the cylinder 4, and the body 5 are in the positional relationship shown in FIG. 4, the eccentric inner ring 9a, outer ring 9b, cam 10, roller 11,
FIG. 5 shows the positional relationship between the cam adapter 12 and the cam adapter 12.

When the crankshaft 15 further rotates counterclockwise from the state shown in FIG. 5, first, the linear portion 10c of the cam 10 comes into contact with the roller 11, and the cam adapter 12
Rises toward the top dead center by the urging force from the coil spring S2. Therefore, the cylinder 4 also has the coil spring S
The urging force from 1 causes the cam adapter 12 to follow and rise toward the top dead center. When the cam 10 further rotates counterclockwise, the small-diameter semicircular portion 10b comes into contact with the roller 11, so that the cam adapter 12 stops at the top dead center. Therefore, the cylinder 4 also stops at the top dead center, and the second through passage 4b communicates with the discharge port 2.

On the other hand, as the crankshaft 15 rotates, the piston 3 descends toward the bottom dead center.
From the second through passage 4b and the discharge port 2. When the piston 3 reaches the bottom dead center, the piston 3, the cylinder 4, and the body 5 return to the positional relationship shown in FIG. 3, and the eccentric inner ring 9a, the outer ring 9b, the cam 10, the roller 11, and the cam adapter 12 Returning to the positional relationship shown in FIG.

The motor 14, the crankshaft 15, the connecting rod 9, the eccentric inner ring 9a and the outer ring 9b correspond to piston driving means in the reciprocating pump of the present invention. On the other hand, the cam 10, the cam adapter 12, the coil spring S1, and the coil spring S2 correspond to the cylinder driving means in the reciprocating pump of the present invention. Since it has a function of mechanically converting into motion, in other words, it is a motion converting cylinder drive device.

In the reciprocating pump of Example 1, the discharge port 2 is completely closed by the side wall surface of the cylinder 4 during suction, and the suction port 1 is completely closed by the side wall surface 4 of the cylinder 4 during discharge. Therefore, once discharged liquid is not sucked into the pump chamber P again from the discharge port 2 at the time of suction.

In the reciprocating pump of Example 1, since the cylinder 4 reciprocates in the vertical direction to open and close the suction port 1 and the discharge port 2, the first through passage 4a and the second through passage 4b
And the opening delay and the closing delay between the suction port 1 and the discharge port 2 hardly occur. Also, since the cylinder 4 moves up and down when the piston 3 is near the top dead center or the bottom dead center, that is, at a position where the amount of up and down movement is small, the first
The through passage 4a maintains a communication state with the suction port 1 of the body 5,
At the time of discharge, the second through-passage 4b maintains a state of communication with the discharge port of the body 5. Therefore, there is no liquid leakage at the start point and the end point of the suction step and the discharge step. Therefore, there is also a feature that the volumetric efficiency of the pump is close to 100%.

When a gas is mixed into the handling liquid sucked into the pump chamber or a gas is generated from the handling liquid, the gas collects in the upper part of the pump chamber P. In the reciprocating pump of Example 1, as described above, during the discharging process,
Since the second through passage 4b in the cylinder 4 is held at the uppermost part of the pump chamber P, the gas is easily discharged to the outside from the second through passage 4b and the discharge port 2 in the first discharge step. Therefore, in the reciprocating pump, even when the pump is restarted after being left for a while in a state where the handling liquid remains in the pump chamber, a so-called gas lock does not occur. Can suck and discharge. Moreover, the reciprocating pump of Example 1 has a feature that a special mechanism for always holding the piston 3 at the bottom dead center when the pump is stopped is unnecessary.

2. Example 2 The internal structure of the reciprocating pump of Example 2 is shown in FIG. 6, the same reference numerals as those in FIGS. 1 and 2 indicate the same elements as those shown in FIGS. 1 and 2.

As shown in FIG. 6, in the reciprocating pump of Example 2, three grooves 5b in the circumferential direction are provided on the inner peripheral surface of the body 5, and the body 5 and the cylinder 4 are provided in the grooves 5b. A seal 6 that seals the space between them is fitted. Grooves 3d and 8d are also provided on the outer peripheral surface of the central portion 3b of the piston 3 and the outer peripheral surface of the protruding portion 8a of the plug 8, respectively, in the circumferential direction. A seal 7A for sealing between the piston 3 and the cylinder 4 is fitted in the groove 3d, and the groove 8d
Has a seal 7B for sealing the protruding portion 8a and the cylinder 4.
Is fitted.

FIG. 7 shows a cross section of the seal 6. As shown in FIG. 7, the seal 6 has an O-ring 6a fitted in the groove 5b, and a cap-shaped slipper seal 6b mounted on the inner periphery of the O-ring 6a. Since the cylinder 4 slides on the inner peripheral surface of the slipper seal 6b on the outer peripheral surface, the slipper seal 6b is preferably formed of a material having a low coefficient of friction, such as fluororesin.

FIG. 8 shows a cross section of the seal 7A. As shown in FIG. 8, the seal 7A has an O-ring 7a fitted in the groove 3d, and a cap-shaped slipper seal 7b mounted on the outer periphery of the O-ring 7a. Since the cylinder 4 slides on the outer peripheral surface of the slipper seal 7b on the inner peripheral surface, the slipper seal 7b is also preferably formed of a material having a low coefficient of friction. In addition, the seal 7B
Has the same configuration as the seal 7A.

The reciprocating pump of Example 2 has the same configuration as that of the reciprocating pump of Example 1 except that it has a seal 6, a seal 7A and a seal 7B.

In the reciprocating pump of Example 2, the body 5
, The inner and outer peripheral surfaces of the cylinder 4, the peripheral and end surfaces of the piston 3, and the outer peripheral surface of the protruding portion 8a of the plug 8 need not be ultra-precision-processed. Therefore, Example 2
The reciprocating pump has a feature that it can be manufactured at lower cost in addition to the features of the reciprocating pump of Example 1.

3. Example 3 The internal structure of the reciprocating pump of Example 3 is shown in FIG.
FIG. 10 shows a perspective view of the piston 3 as viewed from its end face.
9 and 10, the same reference numerals as those in FIGS. 1 and 2 denote the same elements as those shown in FIGS. 1 and 2 unless otherwise specified. FIG. 9 shows the piston 3
Indicates a state in which ejection has been completed after reaching the bottom dead center. A two-dot chain line in FIG. 9 indicates a position at the top dead center of the piston 3.

As shown in FIGS. 9 and 10, the piston 3 in the reciprocating pump of Example 3 is formed in a columnar shape as a whole. Head 3a of the piston 3
The communication groove 3 extends along the axial direction of the piston 3 and is located on the opposite side with respect to the axis.
e and the communication groove 3f are formed. In the reciprocating pump of Example 3, the cross-sectional shape of the communication grooves 3e and 3f is quadrangular, but a groove having a cross-sectional shape such as a triangle and a semicircle is also preferable.

The inner wall surfaces of the communication groove 3e and the communication groove 3f form a part of the pump chamber P together with the inner peripheral surface of the cylinder 4 and the end surface of the projection 8a.

The reciprocating pump of Example 3 is the same as the reciprocating pump of Example 1 except for the shape of the piston 3.

The reciprocating pump of Example 3 has a feature that it is easier to manufacture a piston in addition to the features of the reciprocating pump of Example 1.

The volume of the pump chamber P at the time of completion of discharge is equal to the volume of the space surrounded by the inner wall surfaces of the communication grooves 3e and 3f, the inner peripheral surface of the cylinder 4, and the end surface of the projecting portion 8a of the plug 8. , Is much smaller than the volume of the pump chamber at the completion of discharge in the pump of Example 1. Therefore, Example 3
The reciprocating pump of the second embodiment has a feature that the volume efficiency is higher because the amount of the handling liquid remaining in the pump chamber when the discharge is completed is smaller than that of the reciprocating pump of the first embodiment.

4. Example 4 In the reciprocating pump of Example 4, the piston 3, the cylinder 4, the body 5, the cam adapter 12,
FIG. 11 shows the mutual positional relationship between the cam 10, the connecting rod 9, and the like. In FIG. 11, unless otherwise specified, the same reference numerals as those in FIGS. 1 and 2 indicate the same elements as those shown in FIGS. 1 and 2.

In the reciprocating pump of Example 4, as shown in FIG. 11, contrary to the reciprocating pump of Example 1, the discharge port 2 is formed on the side wall surface of the small inner diameter portion of the body 5 near the lower end opening. The suction port 1 is provided above the discharge port 2, that is, on the side wall surface near the enlarged portion 5 a at the small inner diameter portion.

FIG. 12 shows the positional relationship among the connecting rod 9, the eccentric inner ring 9a, the outer ring 9b, the cam 10, and the cam adapter 12 when the discharge is completed. In FIG. 12, as in FIG. 2, c indicates the center point of the eccentric inner ring 9a.

As shown in FIG. 12, when the ejection is completed, the linear portion 1 of the large-diameter semicircular portion 10a of the cam 10 is formed.
The portion near 0 c is in contact with the roller 11.

When the eccentric inner ring 9a rotates counterclockwise in FIG. 12 from the position shown in FIG. 12, the cam 10 also rotates counterclockwise. As the cam 10 rotates, the linear portion 10c of the cam 10 comes into contact with the roller 11, and the cam adapter 12 rises toward the top dead center by the urging force from the coil spring S2. Therefore, the cylinder 4 follows the cam adapter 12 and rises toward the top dead center by the urging force from the coil spring S1. When the cam 10 further rotates counterclockwise, the small-diameter semicircular portion 10
b contacts the roller 11, the cam adapter 12
Rests at top dead center. Therefore, the cylinder 4 also stops at the top dead center, and the first through passage 4a communicates with the suction port 1.

On the other hand, the piston 3 rises toward the top dead center with the rotation of the eccentric inner ring 9a, so that the handled liquid is sucked into the pump chamber P through the first through passage 4a and the suction port 1. .

When the piston 3 reaches the top dead center and the suction is completed, the portion of the small-diameter semicircular portion 10b of the cam 10 near the linear portion 10d contacts the roller 11.

When the cam 10 further rotates counterclockwise from the above state, first, the linear portion 10d contacts the roller 11, and the cam adapter 12 descends toward the bottom dead center. Therefore, being pushed by the cam adapter 12, the cylinder 4 also descends toward the bottom dead center. When the cam 10 further rotates in the counterclockwise direction, the large-diameter semicircular portion 10a comes into contact with the roller 11, so that the cam adapter 12 and the cylinder 4 also stop at the bottom dead center, and the second through passage 4b and the discharge port 2 Communicate.

On the other hand, as the cam 10 rotates, the piston 3
Descends toward the bottom dead center.
The handling liquid is discharged through the through passage 4b and the discharge port 2.
When the piston 3 reaches the bottom dead center, the piston 3, the cylinder 4, and the body 5 return to the positional relationship shown in FIG. 11, and the connecting rod 9, the eccentric inner ring 9a, and the outer ring 9
b, cam 10, roller 11, and cam adapter 12
Returning to the positional relationship shown in FIG.

5. Others In the reciprocating pump of the present invention, as the cylinder driving means, instead of the motion conversion type cylinder driving device described in the reciprocating pump of Examples 1 to 4, for example, the volume change of the pump chamber is changed by the position of the piston or the like. A volume change detection type that has a volume change detection unit that detects and outputs an electric signal or an hydraulic pressure signal, and a cylinder drive unit that drives a cylinder according to the electric signal or the hydraulic pressure signal from the volume change detection unit. A cylinder driving device may be used.

[0065]

According to the present invention, liquid can be sent without the use of a check valve, there is no liquid leakage, the volume efficiency is high, and even if the handling liquid that easily generates gas is sucked and discharged,
A reciprocating pump without so-called gas lock is provided.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an internal structure of a reciprocating pump of Example 1, which is an example of the reciprocating pump of the present invention.

FIG. 2 is a schematic diagram showing a mutual positional relationship among a connecting rod, an outer ring, an eccentric inner ring, a cam, and a cam adapter in the reciprocating pump of Example 1.

FIG. 3 is a schematic diagram illustrating a mutual positional relationship among a piston, a cylinder, and a body when the discharge of the reciprocating pump of Example 1 is completed.

FIG. 4 is a schematic diagram showing a mutual positional relationship between a piston, a cylinder, and a body at the end of suction of the reciprocating pump of Example 1.

FIG. 5 is a schematic diagram showing a mutual positional relationship among a connecting rod, an eccentric inner ring, an outer ring, a cam, and a cam adapter at the end of suction of the reciprocating pump of Example 1.

FIG. 6 is a cross-sectional view of the reciprocating pump of Example 1 between a body and a cylinder, between a cylinder and a piston,
FIG. 13 is a cross-sectional view illustrating an internal structure of a reciprocating pump of Example 2 in which a seal is provided between a cylinder and a protrusion of a plug.

FIG. 7 is an enlarged sectional view showing details of a seal provided between a body and a cylinder.

FIG. 8 is an enlarged sectional view showing details of a seal provided between a piston and a cylinder.

FIG. 9 is a cross-sectional view showing the internal structure of a reciprocating pump of Example 3 in which a communication groove is provided at the head of a piston.

FIG. 10 is a perspective view of a piston included in the pump of Example 3.

FIG. 11 is a cross-sectional view showing the internal structure of a reciprocating pump of Example 4 which is another example of the reciprocating pump of the present invention.

FIG. 12 is a schematic diagram showing a mutual positional relationship among a connecting rod, an outer ring, an eccentric inner ring, a cam, and a cam adapter in the reciprocating pump of Example 4;

FIG. 13 is a schematic view showing an example of a conventional reciprocating pump.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Suction port, 2 ... Discharge port, 3 ... Piston, 3a ... Head part, 3b ... Central part, 3c ... Handle part, 4 ... Cylinder, 4a
.. 1st through passage, 4b 2nd through passage, 4c ... flange-shaped portion, 5 ... body, 5a ... enlarged portion, 6 ... seal, 6a ... O
Ring, 6b ... slipper seal, 7A ... seal, 7a ...
O-ring, 7b ... slipper seal, 7B ... seal, 8 ...
Plug, 8a: Projecting portion, 9: Connecting rod, 9
a: eccentric inner ring, 9b: outer ring, 10: cam, 10a: large-diameter semicircle, 10b: small-diameter semicircle, 10c: linear part, 10d
... Linear part, 11 ... Roller, 12 ... Cam adapter, 13 ...
Housing, 14 ... motor, 15 ... crankshaft, 16 ...
Pins, 17: washers, S1, S2: coil springs.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3H070 AA07 BB01 BB06 CC29 DD03 DD63 3H075 AA01 BB03 CC16 CC40 DA09 DA14 DB03 EE08 EE16

Claims (2)

[Claims] 1. A body having a suction port and a discharge port formed at a different position in the axial direction with respect to the suction port, and provided inside the body so as to be reciprocally slidable along the axial direction of the body. And a piston having a head portion formed so as to form a pump chamber with a central portion formed to be reciprocally slidable in the cylinder, and an inner surface of the cylinder, wherein the cylinder comprises: It has a first through passage and a second through passage that communicate the inside and outside of the cylinder, and at the time of suction,
The pump chamber and the suction port communicate with each other through the first through passage, and at the time of discharge, the pump chamber and the discharge port are formed to be reciprocally movable such that they communicate with each other through the second through passage. A reciprocating pump. 2. A body having a suction port and a discharge port formed at different positions in the axial direction with respect to the suction port, and a first through path and a second through path communicating between the inside and the outside. A cylinder provided in the body so as to be reciprocally slidable along the axial direction of the body, a central portion formed to be reciprocally slidable in the cylinder, and an inner surface of the cylinder to form a pump chamber. A piston having a leading end formed so as to form; a piston driving means for driving the piston; and a first through passage when the volume in the pump chamber changes from a decreasing tendency to an increasing tendency by driving the piston. Drives the cylinder so that the pump chamber communicates with the suction port, and when the volume in the pump chamber changes from an increasing tendency to a decreasing trend, the second through passage discharges air from the pump chamber. Reciprocating pump bets is characterized by comprising a cylinder drive means for driving the cylinder so as to communicate.