JP2507135Y2 - Structure of suction valve of forced valve type piston pump - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a suction valve structure of a forced valve type piston pump used in a power sprayer,
More specifically, the present invention relates to a suction valve portion structure capable of suppressing impact noise of the valve seat of the suction valve.

[0002]

2. Description of the Related Art In a forced valve type piston pump, a valve seat of an intake valve is displaced relative to a piston rod as the piston rod reciprocates and comes into contact with a valve body and a stopper alternately. Therefore, the contact sound is a cause of noise.

In Japanese Utility Model Laid-Open No. 64-22875 and Japanese Utility Model Laid-Open No. 64-53476, a cushion material is provided on the valve body,
It is disclosed that a shock-absorbing material is interposed between the valve seat and the valve body and the stopper to absorb the shock by the shock-absorbing material and reduce noise.

[0004]

[Problems to be solved by the invention] Shokai 64-2287
The forced valve piston pumps of Japanese Patent Publication No. 5 and Japanese Utility Model Laid-Open No. 64-53476 require stoppers and
The valve seat of the suction valve collides with the valve body and the stopper once per cycle of the forced valve piston pump. Further, when the suction stroke is switched to the discharge stroke, the stroke of the piston rod until the valve seat abutting the stopper abuts the valve body does not substantially discharge the liquid. The discharge amount is small.

The object of the inventions of claims 1 and 2 is to eliminate the stopper so that the contact noise is generated once per cycle of the forced valve type piston pump, and the contact is alleviated.
Accordingly, it is an object of the present invention to provide a suction valve portion structure of a forced valve type piston pump capable of reducing noise and increasing the discharge amount with respect to the stroke of the piston rod.

[0006]

The present invention will be described with reference to the reference numerals of the drawings corresponding to the embodiments. The structure of the suction valve portion of the forced valve type piston pump (10) according to claim 1 is as follows.
It has the component (f). (A) Cylinder body (14) partitioning the pump chamber (62) inside (b) Piston rod moving forward and backward toward the pump chamber (62)
(20) (c) A valve body (28) fixed to the tip of this piston rod (20) and having a diameter smaller than the inner diameter of the cylinder body (14) (d) (d) A piston rod ( 20)
(E) The valve seat (30) (e) which is loosely fitted to the outer peripheral side of the valve seat (30) is slidably contacted with the cylinder body (14) on the outer peripheral side of the valve seat (30). Belleville springs (40, 40b) that have through holes (68) and are connected to one and the other of the valve body (28) and valve seat (30) at the peripheral and central portions, respectively.

The forced valve type piston pump (10) according to claim 2 has a suction valve portion structure according to the first aspect of the forced valve type piston pump (1).
The disc spring (40, which is the constituent element (f) of the suction valve structure of (0)
40g) instead of (g) elastically expandable and contractible in the axial direction, and the valve body (28) and the valve seat (30) at both axial ends, respectively.
The notch (76) that connects with the
It has a bellows body (72).

[0008]

In the invention of claim 1, in the intake stroke, the piston rod (20) retracts with respect to the pump chamber (62), and the valve seat (30).
Due to the pressure difference between both sides and the friction between the cylinder body (14) and the packing (42) toward the tip of the piston rod (20).
It is displaced relative to (20). Disc spring (40, 40b) is seat (30)
Since the valve body (28) is connected to the valve body (28), the valve body (2
The separation of the valve seat (30) from the 8) is limited by the maximum extension amount of the disc springs (40, 40b). On the other hand, with the separation of the valve seat (30) from the valve body (28), the valve body (28) and the valve seat (30) separate from the taper surface portion (66) of the disc springs (40, 40b), and the taper surface portion The through hole (68) of (66) is open. This causes the liquid to
It is introduced into the pump chamber (62) from the through hole (68) of the tapered surface portion (66) of the (0, 40b) via the inner peripheral side of the valve seat (30).

In the discharge stroke, the piston rod (20) is in the pump chamber.
(62), the valve seat (30) moves to the piston rod due to the pressure difference between both sides and the friction between the cylinder body (14) and the packing (42).
It is displaced relative to the piston rod (20) in the proximal direction of (20). The disc springs (40, 40b) are elastically compressed due to the relative displacement of the valve seat (30) toward the valve body (28), and the impact force is alleviated, while the valve spring is provided on the tapered surface portion (66). Body (28) and / or valve seat (3
Abut (0). As a result, the through hole (68) of the tapered surface portion (66)
Is blocked by the valve body (28) and / or the valve seat (30),
The introduction of the liquid into the pump chamber (62) via the (68) is blocked.

In the invention of claim 2, in the suction stroke,
The piston rod (20) retracts with respect to the pump chamber (62) and the valve seat (3
0) is relatively displaced with respect to the piston rod (20) toward the tip end of the piston rod (20) due to the pressure difference on both sides and the friction between the cylinder body (14) and the packing (42). Since the bellows body (72) connects the valve seat (30) and the valve body (28), the valve body (28) is directed toward the tip.
The separation of the valve seat (30) from the is limited by the maximum extension amount of the bellows body (72). On the other hand, with the separation of the valve seat (30) from the valve body (28), the bellows body (72) extends and the notch (76) of the recess (74) is opened. As a result, the liquid is introduced into the pump chamber (62) through the peripheral portion of the valve body (28), the cutout (76) of the recessed portion (74) of the bellows body (72) and the inner peripheral side of the valve seat (30). To be done.

In the discharge stroke, the piston rod (20) is in the pump chamber.
(62), the valve seat (30) moves to the piston rod due to the pressure difference between both sides and the friction between the cylinder body (14) and the packing (42).
It is displaced relative to the piston rod (20) in the proximal direction of (20). The bellows body (72) elastically contracts as the valve seat (30) approaches the valve body (28), and relaxes the contact between the valve body (28) and the valve seat (30). Also, the notch (76) in the depression (74) of the bellows body (72)
Closes as the bellows body (72) shrinks, preventing the introduction of liquid into the pump chamber (62) through the notch (76).

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention will be described below with reference to the embodiments of the drawings. FIG. 2 is a structural diagram of the forced valve piston pump 10. In the forced valve type piston pump 10, the crankcase 11, the suction side manifold 12, the cylinder pipe 14, and the discharge side manifold 16 are arranged in that order along a predetermined axis line, and are joined and fixed to each other adjacent to each other. . The suction pipe 18 is screwed to the lower part of the suction side manifold 12. The piston rod 20 extends in the range from the crankcase 11 to the cylinder pipe 14, and reciprocates by receiving power from a crankshaft (not shown) in the crankcase 11. The oil seal 22 is fixed to the crankcase 11 so that the piston rod 20 can slide on the inner peripheral surface of the oil seal 22, and prevents oil leakage from the inside of the crankcase 11. The seal packing 24 has a piston rod 20
Is fixed to the end of the intake side manifold 12 on the crankcase 11 side so that the
Maintain liquid tightness in 12.

The intake valve 26 has a circular flat plate-like valve body 28 having a diameter smaller than the inner diameter of the cylinder pipe 14 and fixed to the piston rod 20, and a piston rod arranged at the tip side of the piston rod 20 with respect to the valve body 28. And a valve seat 30 that is loosely fitted in 20. The piston rod 20 has a valve body 28 and a collar from the base end side.
32 and the spring washer 36 are fitted in order, and the hexagon nut 38 is
The tip end of the piston rod 20 is screwed together, and they are fastened and fixed in the axial direction. The disc spring 40 is interposed between the valve body 28 and the valve seat 30. The piston packing 42 is fitted on the outer circumference of the valve seat 30 and can slide on the inner circumference of the cylinder pipe 14. The O-rings 44 and 46 are fitted in annular grooves on the outer circumference of both ends of the cylinder pipe 14 in the axial direction, and maintain liquid tightness at the joints between the cylinder pipe 14 and the intake side manifold 12 and the discharge side manifold 16. There is.

The discharge valve 48 is disposed in the discharge side manifold 16, and has a valve seat 50 sandwiched between the cylinder pipe 14 and the discharge side manifold 16 at the peripheral edge, and the valve seat 50.
The valve body 52 that can be seated from the side opposite to the piston rod 20
And a valve sac 54 that accommodates the valve element 52 and is sandwiched between the cylinder pipe 14 and the discharge side manifold 16 together with the valve seat 50 at the periphery, and the valve element fixed to the valve sac 54.
Stopper 56 that limits the movement range of 52 and valve body 52
And a compression coil spring 58 that presses to.

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

FIG. 1 is a detailed structural diagram of the area including the intake valve 26. The disc spring 40, which is elastically compressible in the axial direction, is
It has a tapered surface portion 66 that bulges toward 28, is fixed to the central portion of the valve body 28 at the central portion, and is fixed to the outer peripheral portion of the valve seat 30 at the peripheral portion. The plurality of through holes 68 are tapered surface portions.
66 are formed in the circumferential direction at equal angular intervals, and the inner and outer circumferential surfaces of the tapered surface portion 66 communicate with each other.

The operation of the disc spring 40 will be described. In the intake stroke, the piston rod 20 retracts toward the crankcase 11, and the valve seat 30 causes the piston to move due to the differential pressure between the intake port 60 and the pump chamber 62 and the friction between the cylinder pipe 14 and the piston packing 42. The rod 20 is displaced relative to the piston rod 20 in the tip direction. Since the disc spring 40 connects the valve body 28 and the valve seat 30, the separation of the valve seat 30 from the valve body 28 in the distal direction is restricted by the maximum extension amount of the disc spring 40. On the other hand, with the separation of the valve seat 30 from the valve body 28, the valve seat 30 is separated from the tapered surface portion 66 of the disc spring 40, and the through hole 68 of the tapered surface portion 66 is open. As a result, the liquid in the suction port 60 is introduced into the pump chamber 62 via the outer peripheral side of the valve body 28, the through hole 68 of the tapered surface portion 66 of the disc spring 40, and the inner peripheral side of the valve seat 30.

In the discharge stroke, the piston rod 20 moves into the pump chamber 62.
Toward the base end of the piston rod 20 due to the differential pressure between the suction port 60 and the pump chamber 62 and the friction between the cylinder pipe 14 and the piston packing 42.
Displace relative to. The disc spring 40 is elastically compressed between the valve body 28 and the valve seat 30 as the valve seat 30 contacts the tapered surface portion 66, and the valve body 28 and the valve seat 30 contact each other. Alleviate. Further, the through hole 68 of the tapered surface portion 66 is closed by pressing the valve body 28 against the tapered surface portion 66, and the pump chamber through the through hole 68.
The introduction of liquid into 62 is blocked.

FIG. 3 is a detailed structural view of the range including the suction valve 26 having another disc spring 40b, and FIG. 4 is a perspective view of the disc spring 40b. The disc spring 40b has a central hole 70 having a diameter equal to the inner diameter of the valve seat 30. The disc spring 40b is formed in a direction opposite to the disc spring 40 shown in FIG. It is interposed between the body 28 and the valve seat 30. A plurality of through holes 68 are formed in the tapered surface portion 66 at equal angular intervals in the circumferential direction, and the disc spring 40b has its inner and outer circumferences fixed to the inner circumferential portion of the valve seat 30 and the outer circumferential portion of the valve body 28, respectively. The through hole 68 is blocked by the contact of the valve seat 30 with the tapered surface portion 66.

FIG. 5 shows a bellows body 72 instead of the disc springs 40 and 40b.
FIG. 6 is a front view of the bellows body 72, and FIG. 7 is a vertical sectional view of the bellows body 72. The bellows body 72 is fixed to the outer peripheral portions of the valve body 28 and the valve seat 30 at both ends in the axial direction, is elastically expandable and contractible in the axial direction, and has an annular recess 74.
A plurality of notches 76 are formed in the circumferential direction at equal angular intervals. The notch 76 opens and closes as the bellows body 72 expands and contracts in the axial direction.

The operation of the bellows body 72 will be described. In the intake stroke, the piston rod 20 of the forced valve type piston pump 10 retracts toward the crankcase 11, and the valve seat 30 causes the differential pressure between the intake port 60 and the pump chamber 62 and the cylinder pipe 14 and the piston packing 42. Due to the friction between the piston rod 20 and the piston rod 20, the bellows body 72 expands. Since the bellows body 72 connects the valve body 28 and the valve seat 30,
The separation of the valve seat 30 from the valve body 28 in the distal direction is limited by the maximum extension amount of the bellows body 72. On the other hand, the notch 76 in the depression 74
Opens as the bellows body 72 expands, and the liquid in the suction port 60 is introduced into the pump chamber 62 via the outer peripheral side of the valve body 28, the notch 76 of the bellows body 72, and the inner peripheral side of the valve seat 30.

In the discharge stroke, the piston rod 20 moves into the pump chamber 62.
Toward the base end of the piston rod 20 due to the differential pressure between the suction port 60 and the pump chamber 62 and the friction between the cylinder pipe 14 and the piston packing 42.
Relative to the valve body, the bellows body 72 elastically contracts,
The contact between 28 and the valve seat 30 is reduced. In addition, the depression 74
The notch 76 is closed as the bellows body 72 shrinks,
The introduction of liquid into the pump chamber 62 via 76 is blocked.

[0023]

According to the first and second aspects of the invention, the abutment of the valve seat with the valve body is alleviated by the elastic compression of the disc spring or the bellows body, and the valve seat from the valve body during the discharge stroke is reduced. The separation of the valve is limited not by the contact with the stopper but by the axial extension of the disc spring and the bellows. The contact between the valve seat and the stopper is eliminated, and the valve seat per cycle of the forced valve piston pump is removed. The contact can be made only once. Therefore, noise can be suppressed.

According to the first and second aspects of the present invention, the disc spring or the bellows body is interposed between the valve body and the valve seat, and the through hole of the disc spring is opened and closed to the valve body or the valve seat to the tapered surface portion. Or the opening and closing of the cut of the bellows body is performed by the expansion and contraction of the bellows body. Therefore, the stroke amount of the piston rod required to switch between opening and closing the through hole and the cut is reduced,
The discharge flow rate can be increased with respect to the stroke amount of the piston rod.

[Brief description of drawings]

FIG. 1 is a detailed structural diagram of a range including an intake valve.

FIG. 2 is a structural diagram of a forced valve type piston pump.

FIG. 3 is a detailed structural diagram of a range including an intake valve including another disc spring.

FIG. 4 is a perspective view of a disc spring.

FIG. 5 is a detailed structural diagram of a range including a bellows body instead of a disc spring.

FIG. 6 is a front view of a bellows body.

FIG. 7 is a vertical sectional view of a bellows body.

[Explanation of symbols]

 10 Forced Valve Type Piston Pump 14 Cylinder Pipe (Cylinder Body) 20 Piston Rod 28 Valve Body 30 Valve Seat 40, 40b Disc Spring 42 Piston Packing (Packing) 62 Pump Chamber 66 Tapered Surface 68 Through Hole 72 Bellows Body 74 Recessed Part 76 Cut

Claims (2)

(57) [Scope of utility model registration request] 1. A cylinder body (14) for partitioning a pump chamber (62) inside, a piston rod (20) moving forward and backward toward the pump chamber (62), and a tip of this piston rod (20). Valve body (28) fixed to the part and having a diameter smaller than the inner diameter of the cylinder body (14)
And the piston rod (2
(0) is loosely fitted to the valve seat (30), a packing (42) fitted to the outer peripheral side of the valve seat (30) and slidingly contacting the cylinder body (14) on the outer peripheral side, and a tapered surface portion (66). With a through hole (68) in the peripheral portion and the central portion, respectively, and the valve body (28) and the valve seat
(30) A suction valve section structure for a forced valve type piston pump, comprising: a disc spring (40, 40b) coupled to one side and the other side. 2. A cylinder body (14) for partitioning a pump chamber (62) inside, a piston rod (20) moving forward and backward toward the pump chamber (62), and a tip of this piston rod (20). Valve body (28) fixed to the part and having a diameter smaller than the inner diameter of the cylinder body (14)
And the piston rod (2
A valve seat (30) that is loosely fitted to the valve seat (30), and a packing (42) that is fitted on the outer peripheral side of the valve seat (30) and is in sliding contact with the cylinder body (14) on the outer peripheral side; To the valve body (28) and the valve seat (30) at both ends in the axial direction.
The notch (76) that connects with the
A suction valve portion structure of a forced valve type piston pump, characterized in that it has a bellows body (72).