JPH0521666Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] This invention relates to a forced valve type piston pump that is used to forcefully convey chemical liquids, cleaning liquids, etc., and in which fluid flows into the pump type from approximately the width direction of the piston rod. relates to a forced valve type piston pump that can reduce the impact noise of a suction valve.

[Conventional technology]

FIG. 6 is a longitudinal sectional view of a conventional forced valve type piston pump. In Fig. 6, crankcase 1
0, Suction side manifold 12, cylinder pipe 1
4 and the discharge side manifold 16 are arranged in that order along a predetermined horizontal axis, and are tightened in the axial direction by tightening bolts (not shown) to join and
Fixed. The suction pipe 18 is coupled to the lower part of the suction side manifold 12 by screwing. The piston rod 20 extends from the crankcase 10 to the cylinder pipe 14, and reciprocates by receiving power from a crankshaft (not shown) within the crankcase 10. oil seal 22
is fixed to the crankcase 10 so that the piston rod 20 can slide on its inner circumferential surface, and maintains an oil tightness within the crankcase 10. The seal packing 24 is attached to the suction side manifold 12 so that the piston rod 20 can slide on its inner peripheral surface.
is fixed to the end on the crankcase 10 side to maintain liquid tightness within the suction side manifold 12.

The suction valve 26 includes a circular flat valve body 28 fixed to the piston rod 20 and a valve seat 30 disposed on the tip side of the piston rod 20 from the valve body 28 and loosely fitted to the piston rod 20. are doing. The piston rod 20 includes a valve body 28 and a valve seat 3 from its base end side.
0, collar 32, stopper 34 and spring washer 36
are fitted in order, and the hexagonal nut 38 is screwed onto the tip of the piston rod 20 to tighten and fix them in the axial direction. Valve body 28 and stopper 34
valve seat 30 for piston rod 20 between
The amount of relative movement is set to be less than or equal to the amount of reciprocating movement of the piston rod 20. The stopper 34 is formed with a plurality of through holes 40 passing through it in the axial direction, and the piston packing 42 is fitted onto the outer periphery of the valve seat 30 so as to be able to slide on the inner periphery of the cylinder pipe 14. . The O-rings 44 and 46 are connected to the cylinder pipe 1.
Fitted into annular grooves on the outer periphery of both axial ends of 4,
The joints between the cylinder pipe 14, the suction side manifold 12, and the discharge side manifold 16 are kept liquid-tight.

The discharge valve 48 is disposed within the discharge manifold 16 and has a valve seat 50 sandwiched between the cylinder pipe 14 and the discharge manifold 16 at the periphery, and a valve seat 50 that is opposite to the piston rod 20. A valve body 52 that can be seated from the side, and this valve body 52
and a stopper 56 that is fixed to the valve socket 54 and limits the movement range of the valve body 52. and a compression coil spring 58 that presses the valve body 52 against the valve seat 50.

The suction port 60 is formed within the suction side manifold 12 and the suction pipe 18, and the pump chamber 62 is formed within the cylinder pipe 14 between the suction valve 26 and the discharge valve 4.
8, and the discharge port 64 is formed in the discharge side manifold 16 on the downstream side of the discharge valve 48.

During the suction stroke in which the piston rod 20 moves away from the discharge valve 48 , fluid resistance and sliding resistance between the suction valve 26 and the inner surface of the cylinder pipe 14 act on the valve seat 30 of the suction valve 26 . stoppa 34
, and a gap is created between the valve body 28 and the valve seat 30. Further, since the volume of the pump chamber 62 increases, the fluid (generally fluid is a liquid such as a chemical solution or cleaning fluid) pressure in the pump chamber 62 is small, and the valve body 52 of the discharge valve 48 is moved by the compression coil spring 58.
is pressed against the valve seat 50 by. Therefore, the fluid in the suction port 60 passes through the outside of the valve body 28 of the suction valve 26, enters the gap between the valve body 28 and the valve seat 30, and from there flows between the piston rod 20 and the valve seat 30. a radial gap between and a stopper 34;
It flows into the pump chamber 62 through the through hole 40 .

During the discharge stroke in which the piston rod 20 moves toward the discharge valve 48, the pump chamber 62 is located in the valve seat 30 of the suction valve 26.
Since a large pressure is applied from the side, the valve seat 30 is pressed against the valve body 28, and communication between the suction port 60 and the pump chamber 62 is cut off. Further, since the volume of the pump chamber 62 decreases, the fluid pressure within the pump chamber 62 increases, and the valve body 52 of the discharge valve 48 is moved away from the valve seat 50 against the compression coil spring 58. Therefore, the fluid in the suction port 60 flows through the discharge valve 48.
It exits from the pump chamber 62 to the discharge port 64 via.

In a forced-valve type piston pump equipped with such a forced-valve type suction valve, the suction valve 26 is automatically opened and closed by the reciprocating movement of the piston packing 42, so that the suction valve 26 is automatically opened and closed when the pump rotates, especially at high rotation speeds.
In addition, since the fluid flows in almost the same direction in the range from the suction valve 26 to the discharge valve 48, the inertia of the fluid is used to fill the pump chamber 62, and the forced The volumetric efficiency of valve type piston pumps is increased.

[Problem that the invention attempts to solve]

However, in a forced valve type piston pump, at the start of the discharge stroke and the suction stroke, the valve body 2 of the suction valve 26
8 collides with the valve seat 30 and stopper 34 with great force, and the accompanying hitting sound is transmitted to the crankcase 10 via the piston rod 20 and the crankshaft (not shown) supported by the piston rod 20. do.
Since the space inside the crankcase 10 acts like the cavity of a drum, the air inside the crankcase 10 resonates, increasing noise. This is a disadvantage of forced-valve piston pumps compared to ordinary plunger pumps that are not forced-valve type.

Furthermore, when replacing the piston packing 42 due to wear or the like, it is necessary to loosen or tighten the hexagonal nut 38, which makes the replacement work complicated.

During the suction stroke, the outer circumferential edge of the piston packing 42 does not come into secure sliding contact with the inner circumference of the cylinder pipe 14,
Fluid may leak from between the outer circumference of the piston packing 42 and the inner circumference of the cylinder pipe 14.

In addition, Utility Application No. 148042 (Sho 64-53476)
(No. 2003) discloses a forced valve type piston pump that reduces impact noise by disposing a buffer member between the valve seat of the suction valve and the valve body and/or stopper. It needs to be fixed in place.

The purpose of this invention is to provide a forced valve type piston pump that can omit a stopper for the suction valve and reduce impact noise between the valve seat of the suction valve and the stopper.

This invention further aims to ensure that the annular piston seal contacts the inner surface of the cylinder body in a forced valve type piston pump, and to facilitate the replacement work of the annular piston seal, the valve body and the valve seat of the suction valve. The purpose is also to

[Means for solving problems]

The invention will be described using reference numerals in the drawings that correspond to the embodiments. The forced valve type piston pump of this invention includes a cylinder body 14 that defines a pump chamber 62 therein, a piston rod 20a that reciprocates in the axial direction of the cylinder body 14, and through holes 80, 80 in the center.
The valve seat 78, 78b with b and this valve seat 78, 7
an annular piston packing 82 that is integrally fixed to the piston rod 8b and slides on the inner surface of the cylinder body 14; Valve bodies 76, 76b that open and close the through holes 80, 80b;
In the part of the reciprocating range of the piston rod 20a on the pump chamber 62 side, the valve seats 78, 78b are connected to the valve bodies 76, 76b.
and a biasing means 86 for biasing toward.

Further, the biasing means 86 may be a compression coil spring 86, and the bottom dead center of the valve bodies 76, 76b may be located away from the position of the valve seats 78, 78b in the free length of the compression coil spring 86. .

The annular piston packing 82 has a V-shaped groove that opens toward the biasing means 86, and the male adapter 88 is inserted into this V-shaped groove.
The biasing means 86 is inserted into the shaped groove and the male adapter 8
Preferably, the annular piston packing 82 is biased through the annular piston packing 82.

The valve bodies 76 and 76b may be detachably fixed to the tip of the piston rod 20a, and the cylinder body 14 may be separable from the crankcase 10.

Preferably, the valve body 76b is formed in a spherical shape convex toward the valve seat 78, and the seat surface of the valve seat 78 is formed in a spherical concave surface.

It is preferable that a plurality of through holes 80b are formed in the valve seat 78b.

[Effect]

During the suction stroke, the piston rod 20a moves toward the proximal end, thereby causing the annular piston seal 8
2 is moved toward the valve bodies 76, 76b integrally with the valve seats 78, 78b by the urging means 86,
The valve bodies 76, 76b are separated from the valve seats 78, 78b. The fluid flows through the valve bodies 76, 76b and the valve seats 78, 78.
b and the through hole 8 of the valve seats 78, 78b.
0, 80b and into the pump chamber 62.
The peripheral edge of the valve body 76, 76b is connected to the valve seat 78, 78b.
If the tapered surface tapers toward , the fluid flows smoothly along this tapered surface, reducing resistance.

In the discharge stroke, the piston rod 20a moves toward the tip, so that the valve bodies 76, 76b abut against the valve seats 78, 78b from the side opposite to the pump chamber 62,
While closing the through holes 80, 80b in the center of the valve seats 78, 78b, the valve seats 78, 78b are closed by the biasing means 8.
6 in the direction of reducing the volume of the pump chamber 62. The fluid in the pump chamber 62 is discharged from the pump chamber 62.

During the discharge stroke, the V-shaped groove of the annular piston packing 82 is pushed into the male adapter 88 as the valve seats 78, 78b are carried toward the pump chamber 62 by the piston rod 20a. As a result, the V-shaped groove of the annular piston seal 82 is pushed open by the male adapter 88, and the annular piston seal 82 is pushed open.
The outer periphery of No. 2 is securely in sliding contact with the inner periphery of the cylinder body 14.

The cylinder body 14 is separated from the crankcase 10, and the crankcase 10 side of the cylinder body 14 is in an open state. In this way, the annular piston packing 82 and the valve seats 78, 78b can be taken out and assembled from the open end of the cylinder body 14.
Further, with this separation, the valve bodies 76, 76b are exposed, and the valve bodies 76, 76b are exposed from the tip of the piston rod 20a.
6, 76b can be disassembled and assembled.

When the valve body 76b is formed in a spherical shape convex toward the valve seat 78, the fluid flows toward the valve seat 78b along the spherical surface of the valve body 76b.

〔Example〕

This invention will be described below with reference to the embodiments shown in FIGS. 1 to 5. In addition. For parts that overlap with the explanation of FIG. 6, the same reference numerals are used, and
The explanation will be omitted and only the differences from FIG. 6 will be explained.

FIG. 1 is a longitudinal sectional view of a forced valve type piston pump. The piston rod 20a is attached to the crankcase 10
It is driven by a crankshaft (not shown) inside and reciprocates within the crankcase 10, the suction side manifold 12, and the cylinder pipe 14 as a cylinder body. The connection fitting 66 is connected to the suction side manifold 12
and the cylinder pipe 14, and the outer periphery of both ends of the connecting fitting 66 is connected to the suction side manifold 1.
2 and the inner periphery of the cylinder pipe 14. The connecting fitting 68 is interposed at the joint between the cylinder pipe 14 and the discharge side manifold 16, and the outer periphery of both ends of the connecting fitting 68 fits into the inner periphery of the cylinder pipe 14 and the discharge side manifold 16. O
The rings 70 and 72 are connected to the connecting fittings 66 and 6, respectively.
It is fitted into the annular groove of the fitting surface on the outer periphery of 8 for sealing. The connecting fittings 66, 68, together with the suction side manifold 12, cylinder pipe 14, and discharge side manifold 16, are fastened to the crankcase 10 by tightening bolts (not shown). The suction valve 74 includes a valve body 76 and a valve seat 78, and the valve body 76 is removably fixed to the tip of the piston rod 20a by screwing. The through hole 80 is connected to the valve seat 7.
8 and is opened and closed by a valve body 76. The annular piston packing 82 is connected to the pump chamber 62.
It has a V-shaped groove that opens on the side, is fitted onto the outer periphery of the valve seat 78, and is in sliding contact with the inner periphery of the cylinder pipe 14 at the lip portion of the outer periphery. The annular groove 84 is formed on the end surface of the connecting fitting 68 on the annular piston packing 82 side. The compression coil spring 86 is engaged at both ends with the V-shaped groove of the annular piston packing 82 and the annular groove 84 of the connecting fitting 68, and has a predetermined free length in the axial direction, and when compressed, the compression coil spring 86 engages the valve seat 78.
is urged toward the valve body 76. That is, the valve body 76
The bottom dead center of is away from the position of the valve seat 78 in the free length of the compression coil spring 86. Instead of adjusting the free length of the compression coil spring 86 in this way, a stopper may be provided on the inner surface of the cylinder pipe 14 to restrict the range of movement of the valve seat 78 toward the crankcase 10.

The main functions of the embodiment shown in FIG. 1 will be explained.

In the suction stroke, the piston rod 20a moves toward the crankcase 10, and thereby the annular piston packing 82 moves toward the valve body 76 together with the valve seat 78 by the compression coil spring 86 as a biasing means. At the same time, the valve body 76 separates from the valve seat 78. Fluid (usually liquid) flows between the valve body 76 and the valve seat 78.
It is introduced into the pump chamber 62 through the gap between the valve seat 78 and the through hole 80 of the valve seat 78.

In the discharge stroke, the piston rod 20a moves into the pump chamber 6
As a result, the valve body 76 contacts the valve seat 78 from the side opposite to the pump chamber 62, closes the through hole 80 in the center of the valve seat 78, and presses the valve seat 78 against the compression coil spring 86. It is dragged toward the discharge side manifold 16 against the pressure. The fluid in the pump chamber 62 is discharged from the pump chamber 62 via the discharge valve 48 .

By loosening the tightening bolts, the cylinder pipe 14 is separated from the suction side manifold 12,
The suction side manifold 12 side of the cylinder pipe 14 is in an open state. The compression coil spring 86 and the valve seat 78 can be taken out and assembled from this open end. Further, with this separation, the valve body 76 is exposed, and the valve body 76 is exposed from the tip of the piston rod 20a.
6 can be disassembled and assembled.

FIG. 2 is a cross-sectional view of a portion of a forced-valve piston pump that includes a male adapter 88 to improve the sealing of the annular piston packing 82. The annular piston packing 82 has a V-shaped groove opening toward the compression coil spring 86 on the surface on the compression coil spring 86 side, and the annular male adapter 88 connects the corner portion to the V-shaped groove of the annular piston packing 82. Partially inserted into the groove. During the discharge stroke, the V-shaped groove of the annular piston packing 82 is pushed into the male adapter 88 as the valve seat 78 is carried toward the pump chamber 62 by the piston rod 20a. As a result, the V-shaped groove of the annular piston packing 82 is pushed open by the corner of the male adapter 88, and the outer periphery of the annular piston packing 82 reliably slides into contact with the inner periphery of the cylinder pipe 14. Therefore, the sealing performance between the outer periphery of the annular piston packing 82 and the inner surface of the cylinder pipe 14 is improved.

FIG. 3 shows a modification of the valve body of the suction valve 74. The valve body 76b is formed in a spherical shape convex toward the valve seat 78, and the seat surface of the valve seat 78 is formed as a spherical convex surface. During the suction stroke, the fluid flows along the spherical surface of the valve body 76b, reducing resistance and increasing suction efficiency. Further, even if the axes of the valve body 76b and the valve seat 78 are slightly shifted in the radial direction, the valve body 76b and the valve seat 78 are properly brought into close contact with each other due to the spherical surfaces.

4 is a side view of the suction valve 74 provided with another valve seat, and FIG. 5 is a view of the valve seat of FIG. 4 viewed from the valve body side. The center portion of the valve seat 78b is formed into a plate shape, and a plurality of through holes 80b are bored in this center portion. In FIGS. 1-3, the valve bodies 76, 76b must have a larger diameter than the through hole 80 of the valve seat 78, whereas in FIGS.
6 only needs to close all the through holes 80b by contacting the plate-shaped central portion of the valve seat 78b, so that the diameter of the valve body 76 can be reduced. Also, the strength of the valve seat 78b in the radial direction is increased.

[Effect of idea]

In this way, according to this invention, the stopper that restricts the movement range of the valve seat of the intake valve is omitted, so collision between the stopper and the valve seat is eliminated, collision noise is prevented, and the forced valve type piston Noise during operation of the pump can be reduced. Eliminating the stopper eliminates obstructions at the fluid introduction portion to the pump chamber, thereby facilitating fluid introduction into the pump chamber and improving suction efficiency.

The annular piston seal opens toward the biasing means V
The male adapter is fitted into the V-shaped groove, and the biasing means biases the annular piston packing via the male adapter. Therefore, during the discharge stroke, the male adapter is pushed into the V-shaped groove of the annular piston seal and pushes the V-shaped groove open, so that the outer periphery of the annular piston seal securely slides into contact with the inner periphery of the cylinder body. Improves sealing performance.

The valve body is detachably fixed to the tip of the piston rod, and the cylinder body is separable from the suction side manifold. Therefore, by separating the cylinder body from the suction side manifold, it becomes possible to take out and assemble the valve seat and the annular piston packing from this separation point, and this separation also exposes the valve body and attaches the valve body to the piston. It can be assembled and disassembled at the tip of the rod. Therefore,
The efficiency of replacing these annular piston packings and the like is improved.

Since the valve body has a spherical shape convex toward the valve seat, fluid flows along the spherical surface of the valve body during the suction stroke, reducing resistance and increasing suction efficiency. Furthermore, even if the axes of the valve body and valve seat of the suction valve are slightly misaligned in the radial direction, the valve body and the valve seat can be properly brought into close contact due to the contact between the spherical surfaces, and collision noise can be reduced.

[Brief explanation of the drawing]

Figures 1 to 5 relate to an embodiment of this invention, with Figure 1 being a vertical sectional view of a forced valve type piston pump, and Figure 2 being a longitudinal sectional view of a forced valve type piston pump.
The figure is a cross-sectional view of a forced valve type piston pump equipped with a male adapter to improve the sealing performance of the annular piston seal, Figure 3 is a diagram showing a modification of the valve body of the suction valve, and Figure 4 is a diagram showing another example of the valve body of the suction valve. FIG. 5 is a side view of a suction valve equipped with a valve seat, FIG. 5 is a view of the valve seat shown in FIG. 4 viewed from the valve body side, and FIG. 6 is a longitudinal cross-sectional view of a conventional forced valve type piston pump. 10... Crank case, 14... Cylinder pipe (cylinder body), 20a... Piston rod, 7
6, 76b... Valve body, 78, 78b... Valve seat, 8
0,80b...Through hole, 82...Annular piston seal, 86...Compression coil spring (biasing means), 8
8...Male adapter.

Claims (1)

[Claims for Utility Model Registration] (1) Cylinder body 1 defining a pump chamber 62 therein
4, a piston rod 20a that reciprocates in the axial direction of this cylinder body 14, and through holes 80, 8 in the center.
Valve seats 78, 78b with 0b and this valve seat 7
an annular piston packing 8 that is integrally fixed to the cylinder body 8 and 78b and slides on the inner surface of the cylinder body 14;
2, the through hole 80 of the valve seats 78, 78b fixed to the tip of the piston rod 20a and seated on the valve seats 78, 78b from the side opposite to the pump chamber 62;
The valve bodies 76, 76b which open and close 80b and the valve seats 78, 78b are connected to the valve body 7 in the pump chamber 62 side of the reciprocating range of the piston rod 20a.
6, 76b. (2) The biasing means 86 is a compression coil spring 86, and the bottom dead center of the valve bodies 76, 76b is away from the position of the valve seats 78, 78b in the free length of the compression coil spring 86. The forced valve type piston pump according to claim 1, characterized in that: (3) The annular piston packing 82 has a V-shaped groove that opens toward the biasing means 86 side, the male adapter 88 fits into this V-shaped groove, and the biasing means 86 has a V-shaped groove that opens toward the biasing means 86 side. 3. The forced valve type piston pump according to claim 1, wherein said annular piston packing 82 is biased through said annular piston packing 82. (4) The valve bodies 76, 76b are connected to the piston rod 20.
The forced valve type piston pump according to any one of claims 1 to 3, wherein the cylinder body (14) is detachably fixed to the tip of the cylinder (a), and the cylinder body (14) is separable from the crankcase (10). (5) The valve body 76b is formed in a spherical shape convex toward the valve seat 78, and the seat surface of the valve seat 78 is formed in a spherical concave surface. A forced valve type piston pump according to any of the above. (6) A plurality of the through holes 80b are provided in the valve seat 78b,
A forced valve piston pump according to any one of claims 1 to 5.