JP2665777B2 - Self-regulating electromagnetic pump with pressure rise time adjustment mechanism - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an electromagnetic pump used for hydraulic transmission of a small boiler using, for example, a gun type oil burner.

(Prior art) The requirements for the discharge pressure characteristics of this type of electromagnetic pump are:
Speeding up the discharge pressure up to the ignition point to eliminate non-combustible discharge oil, slowing down the discharge pressure near the ignition point to reduce explosion sound caused by ignition, and efficiently driving the electromagnetic pump For this reason, reduce the amount of leakage from the pump in the steady state, release the residual pressure in the pump immediately after stopping to prepare for the next ignition, and reduce the discharge pressure of the electromagnetic pump in the steady state. And so on.

In order to satisfy such a demand, the applicant of the present application has filed an application, which is disclosed in Japanese Patent Application Laid-Open No.
It is known as Japanese Patent No. 173. In this conventional example, a plunger is slidably inserted into a cylinder connected to a downstream side of a discharge valve and an upstream side of a suction valve, and the inside of the cylinder is divided into a high-pressure chamber and a low-pressure chamber, and the high-pressure chamber and the low-pressure chamber are separated from each other. A first chamber that communicates with the side chamber via an orifice formed in the plunger, and further interrupts communication between the high-pressure side chamber and the low-pressure side chamber until the pressure of the high-pressure side chamber increases and the plunger moves to a predetermined value. A valve and a second valve for allowing a small amount of liquid to leak when the pressure of the high-pressure side chamber rises and cutting off the communication between the high-pressure side chamber and the low-pressure side chamber are provided.

Further, a relief valve for returning an excessive flow rate equal to or higher than a preset pressure from the discharge side to the suction side is provided in parallel with the cylinder.

Therefore, when the electromagnetic pump is driven, the communication between the high-pressure side chamber and the low-pressure side chamber is initially interrupted by the first valve, so that the discharge pressure sharply rises to a predetermined value, and then the first valve opens to open the high-pressure chamber. Since the side chamber and the low-pressure side chamber communicate with each other through the orifice, the discharge pressure rises slowly, and ignition is performed at this time. When the pressure in the high pressure side chamber further rises,
The high pressure side chamber and the low pressure side chamber are closed by the second valve while allowing a small amount of liquid leakage, so that the discharge pressure increases to a preset pressure set by the relief valve. Then, when the drive of the electromagnetic pump is stopped, the plunger is urged to the high pressure side chamber by the main spring, so that the plunger returns to the original position. You can get.

(Problems to be Solved by the Invention) However, according to the above-described device, once the discharge pressure reaches a steady pressure, the pump operates the relief valve as an extra flow inside the pump in addition to the flow discharged from the nozzles after the outside. Flow amount returned to the pump suction side through the pump, and the amount leaked to the suction side from the minimum clearance between the plunger and the second valve through the orifice of the plunger while the plunger presses the second valve in response to the discharge pressure. Therefore, even in a steady state, the piston stroke is constant and large, which causes a large pulsation in the discharge pressure, and also increases the vibration and noise of the electromagnetic pump itself and the combustion pulsation noise.

Therefore, in the present invention, in addition to the demand for the conventional discharge pressure rise characteristics, not only the pulsation of the discharge pressure in the steady state and the vibration and noise of the electromagnetic pump are reduced, but also the pressure rise time adjustment which can reduce the combustion pulsation noise. An object of the present invention is to provide a self-regulating electromagnetic pump having a mechanism.

(Means for Solving the Problems) The gist of the present invention is that the volume of the pump chamber 9 is changed by intermittent energization of the electromagnetic coil 2 to reciprocate the piston 7 to change the volume of the pump chamber 9. The liquid is sucked from the suction hole 12 for the cooperative operation of the suction valve 10 and the discharge valve 11 due to the change in the volume of the chamber 9, pressurized, and discharged through the solenoid valve 16.
In an electromagnetic pump designed to deliver more pressure, the cylinder
Slide the plunger 39 into the cylinder 39
Is partitioned into a high-pressure side chamber 42 and a low-pressure side chamber 43 connected to the discharge side on the downstream side of the discharge valve 11, and the high-pressure side chamber 42 and the low-pressure side chamber 43 are orifices 53 formed in the plunger 19.
And the plunger 39 is connected to the low-pressure side chamber 43.
The plunger is pressed against the high pressure side chamber 42 by the main spring 50
A first valve 54 is provided to shut off the communication between the high-pressure side chamber 42 and the low-pressure side chamber 43 until the movement of the valve 29 exceeds a predetermined value.
The second valve 60 is connected to the low pressure side chamber 43 and the suction side passage 46 until the movement of the valve 39 becomes maximum, and restricts the communication between the low pressure side chamber 43 and the suction side passage 46 when the movement becomes maximum. And a pressure-reducing valve 66 for restricting the flow rate flowing through the passage on the passage between the discharge valve 11 and the discharge hole 18 on the downstream side of the discharge valve 11. The cylinder is displaced by a pressure receiving plunger 69 to which side pressure is applied, and is slidably provided in another cylinder 70 provided separately from the pressure receiving plunger 69 and the cylinder 29, and sandwiches the pressure receiving plunger 69 of another cylinder 70. A pressure regulating spring is provided in the chamber 72 on the side opposite to the pressure reducing valve.
73, and a pressure adjusting mechanism 65 in which a return passage 76 communicating with the suction-side passage of the electromagnetic pump is formed in the chamber 72 on the side opposite to the pressure reducing valve.

(Operation) Therefore, when the electromagnetic pump is driven and the discharge pressure after the discharge valve 11 rises, the discharge pressure is increased by the communication between the high pressure side chamber 42 and the low pressure side chamber 43 of the pressure rise time adjusting device 23. When the plunger 39 moves to a predetermined value, the first valve 54 is opened, and the high pressure side chamber 42 and the low pressure side chamber 43 communicate with each other through the orifice 53. When the plunger 39 moves to the maximum, the second valve 69 causes the low pressure side chamber to rise.
The communication between 43 and the return passage 76 is narrowed, and the discharge pressure achieves a predetermined rise characteristic, and the discharge pressure is reduced by a pressure reducing valve 66 provided in a passage between the discharge valve 11 and the discharge hole 18 on the downstream side. The pressure is increased to the set pressure set by the pressure adjusting mechanism including the pressure. At this time, the pressure reducing valve 66 is displaced by the pressure receiving plunger 69 to which the set pressure is applied, and the throttle amount is adjusted in comparison with the flow rate according to the set pressure flow rate, so that the stroke of the piston 7 also obtains the required set pressure. In a sufficient amount. Since a discharge pressure that is higher than the set pressure is applied to the pressure rise time adjustment mechanism 65, the amount of leakage from the pressure rise time adjustment mechanism 65 is reduced or eliminated as compared with the conventional example. be able to.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIGS. 1 to 4 show an actual electromagnetic pump 1 according to the present invention, and FIG. 5 shows the electromagnetic pump 1 rewritten on a plane in order to clarify the connection state of each component. In the figure, the electromagnetic pump 1 includes an electromagnetic plunger 3 which reciprocates due to an intermittent electromagnetic force of an electromagnetic coil 2 and an upper holding spring 4 and a lower holding spring 5 and an electromagnetic plunger working chamber 6. Is held in. The piston 7 is located below the electromagnetic plunger 3.
The pump chamber 9 is connected integrally with the electromagnetic plunger 3 and inserted into the cylinder 8. The reciprocating motion of the piston 7 changes the volume of the pump chamber 9, and performs a pump action in cooperation with the suction valve 10 and the discharge valve 11. That is, the liquid (for example, petroleum) sucked into the pump chamber 9 from the suction hole 12 through the suction valve 10 has a discharge pressure of, for example, about 10 kg / cm ² from the discharge valve 11 and flows through the discharge pressure introduction passage 44. As described below, the pressure rise time adjusting mechanism 23 described below, the accumulator 20 via the discharge side passage 63, and reaches the pressure adjusting mechanism 65 described below, the pressure is adjusted to a set pressure by the pressure adjusting mechanism 65, the electromagnetic plunger working chamber 6 and a hole 13 formed in the electromagnetic plunger 3 and a fixed magnetic rod 14
Through the hole 15 formed in the discharge joint 17 through the electromagnetic valve 16 which is attracted by the electromagnetic coil 2 and is opened against the spring 16a. Is discharged to the

The pressure rise time adjusting mechanism 23 controls the pressure rise characteristics as shown in FIGS. 2, 3, 5 and 8, and is integrated with the pump body 24 as shown in FIG. One end of the body portion 25 is open, and one end of the body portion 25 is closed by a lid 26, and the lid 26 is screwed to the body 25 by bolts 27. A cylinder 29 is inserted into the body part 25,
The left end of 29 abuts on the inner surface of lid 26, and the O-rings 30, 31 between the outer peripheral surface of cylinder 29 and the inner peripheral surface of body portion 25.
Are interposed respectively.

A valve case 33 is inserted into a concave portion 32 formed at the left end of the cylinder 29 via an O-ring 38. The valve case 33 has a base 33 having the same diameter as the diameter of the recess 32.
a, and a convex portion 33b having a smaller diameter than the concave portion, the left end of the base portion is in contact with the lid 26 like the cylinder 29, and the right end of the convex portion 33b is formed in the middle of the cylinder 29. The annular space 35 is fixed by being in contact with and fixed to the bottom portion 34, which is surrounded by the outside of the projection 33b and the cylinder 29, and the valve storage chamber 55 is formed by the inside of the projection 33b and the bottom 34, respectively. . on the other hand,
A plurality of through holes 36 and 37 facing the annular space 35 are formed in the outer circumferential surface and the bottom portion 34 of the cylinder 29 in the circumferential direction and the axial direction, respectively.

Plunger 39 has O-ring 4 inside right side of cylinder 29.
The cylinder 29 is partitioned into a high-pressure side chamber 42 and a low-pressure side chamber 43 by the plunger 39. The high-pressure side chamber 42 is connected to the discharge pressure introduction passage 44 connected to the downstream side of the discharge valve 11 and the annular space 35 described above.
And through holes 36 and 37. The low-pressure side chamber 43 communicates with a suction side passage 46 connected to the upstream side of the suction valve 10 through a communication groove 45 formed at the right end of the cylinder 29.

The plunger 39 is formed by fitting an orifice nozzle main body 48 into a cylindrical plunger main body 47 via an O-ring 49, and is mounted between the orifice nozzle main body 48 and the above-described body portion 25. It is pressed by the main spring 50 toward the high pressure side chamber 42. In addition, this plunger 39, (plunger body 47, orifice body 41)
A communication hole 51 is formed in the center axis direction, a filter 52 is arranged between the plunger main body 47 and the orifice nozzle main body 48, and an orifice 53 is formed on the orifice nozzle main body 48 side.

The first valve 54 is provided in a valve storage chamber 55 formed in the projection 33b of the valve case 33 described above. The first valve 54 has a valve body 56 and a pressing spring 57 for pressing the valve body 56 toward the bottom 34. The valve body 56 is moved by a predetermined value when the plunger 39 moves by a predetermined value. A central hole 58 formed in the center of the bottom 34 of the cylinder 29 until it contacts the bottom 34 of the cylinder 29
The valve abuts on a valve seat 59 formed on the plunger 39 so as to protrude therefrom, and closes one end of a communication hole 51 extending to the valve seat 59.

The second valve 60 is located between the plunger 39 and the body portion 25 in the low-pressure side chamber 43, and has a movable seat portion 61 formed near the right peripheral edge of the plunger 39. The fixed sheet portion 62 is provided on the body portion 25 side to face. The fixing sheet portion 62 is formed of a ring-shaped packing made of a soft material such as rubber or plastic, and is fixed to a step formed on the body portion 25.

Reference numeral 65 denotes a pressure adjusting mechanism provided on the discharge-side passage 63 (referred to as a passage from the discharge valve 11 to the electromagnetic plunger working chamber 6), as shown in FIGS. 2, 4, and 5. A pressure reducing valve 66 is disposed in the passage 63, and the flow passage area is appropriately reduced by the pressure reducing valve 66 and the throttle hole 67 to control the flow rate of the flowing fluid. .

The pressure reducing valve 66 is in contact with a pressure receiving plunger 69 which is a pressure receiving mechanism via a rod 68, and is moved by the displacement of the pressure receiving plunger 69.

The pressure receiving plunger 69 is connected to another cylinder 70 provided in parallel with the cylinder 29 with respect to the suction valve 10 and the discharge valve 11.
It is slidably placed inside. An elastic member 71 such as an O-ring provided on the pressure receiving plunger 69 is interposed between them, and the elastic member 71 effectively absorbs small pulsation generated in the pressure receiving plunger 69.

A pressure regulating spring 73 is housed in the anti-reducing valve side chamber 72 with the plunger 69 of the cylinder 70 interposed therebetween.
69 is pressed in the direction of the pressure reducing valve, and when the pump is stopped, the pressure reducing valve 66 moves to the left most against the spring 74 with a small load, and the degree of opening with the throttle hole 67 becomes maximum. I have. Reference numeral 75 denotes a pressure adjusting screw, which can be rotated to adjust the set force of the spring and adjust the discharge pressure.

The return passage 76 has one end opening to the chamber 72 on the side of the cylinder 70 opposite to the pressure reducing valve, and the other end opening to the suction side of the electromagnetic pump. Therefore, even if the fluid leaks into the chamber 72 of the cylinder 70 on the side opposite to the pressure reducing valve, the fluid is returned to the suction side at any time via the return passage 76 by the negative pressure on the suction side.

In the above-described configuration, when a pulse is supplied to the electromagnetic coil 2, it is excited, the electromagnetic plunger 3 is attracted and displaced against the upper holding spring 4, and energy is stored in the upper holding spring 4. When the supply of the pulse is stopped, the electromagnetic coil 2 is de-energized, and is returned to the upper holding spring 4 in sequence. When the pulse is supplied again, the electromagnetic plunger 3 is repeatedly displaced and reciprocated against the upper holding spring 4 as described above. Accordingly, the piston 7 also reciprocates, so that a pump action is performed by the suction valve 10 and the discharge valve 11, and the liquid sucked from the suction port 12 through the suction valve 10 is pressurized by the piston 7 and is discharged from the discharge valve 11. Is discharged through.

The pressurized liquid is guided from the discharge pressure introducing passage 44 to the pressure rise time adjusting device 23, and from the discharge side passage 63 to the pressure adjusting mechanism 65 including the pressure reducing valve 66 and the like. As the discharge pressure (the pressure between the discharge valve 11 and the pressure reducing valve 66) increases due to the discharge side load (generated by the nozzle of the discharging device), the pressure of the high pressure side chamber 42 also increases. Thereby, the left end face of the plunger 39 is pressed, and the plunger 39 moves rightward against the main spring 50 from the state shown in FIG. In this case, since the valve body 56 of the first valve 54 is pressed by the pressing spring 57 and remains seated on the valve seat 59 of the plunger 39, the communication between the high-pressure side chamber 42 and the low-pressure side chamber 43 is cut off. As a result, the leakage of the liquid is prevented, and the pumping capacity is used only for discharging the liquid and moving the plunger 39, so that the discharge pressure sharply increases as shown in FIG.

When the plunger 39 moves further, the valve body 56 of the first valve 54 moves to the bottom 34 of the cylinder 29 as shown in FIG.
Abut. This is P ₁ point shown in FIG. 8.

Thereafter, as shown in FIG. 7, the valve seat portion 59 of the plunger 39 is separated from the valve body 56 of the first valve 54, so that the first valve 54
Is opened, and the high pressure side chamber 42 and the low pressure side chamber 43 are communicated through the communication hole 51. For this reason, the liquid in the high-pressure side chamber 42 leaks into the low-pressure side chamber 43 at a rate determined by the diameter of the orifice 53, and the rising speed of the discharge pressure P decreases, and ignition occurs after t ₂ hours (for example, 1 second) in this state done ignition reached the point P _2, the discharge pressure at this time is for example 3.5 kg / cm ^2. Since the rising speed of the discharge pressure at this ignition point is slow, explosive ignition is prevented and the ignition is performed quietly.

When the pressure in the high-pressure side chamber 42 further increases, as shown in FIG. 8, the movable seat portion 61 of the plunger 39 finally comes into contact with the fixed seat portion 62 on the body portion 25 side so that the second valve 60 closes. I do. This is the P ₃ point shown in FIG.
The P ₃ points after the discharge pressure is rapidly increased again.

However, in the period from the P ₃ points until a steady pressure (set pressure P _4), the movable seat 61 is fixed seat portion 62
When the low pressure side chamber 43 is completely closed, the pressure of the low pressure side chamber 43 becomes equal to the pressure of the high pressure side chamber 42, and the forces received from both sides of the plunger 39 become substantially equal (the movable seat portion 61 is located near the peripheral edge). The plunger 39 is moved leftward by the return force of the main spring 50 because the pressure receiving area on both sides of the plunger 39 is not so large. Then, the low-pressure side chamber 43 communicates with the suction-side passage 46, and the pressure in the low-pressure side chamber 43 is reduced, and the movable seat portion 61 of the plunger 39 tries to contact the fixed seat portion 62 again. This is the case when viewed microscopically, and in actuality, the plunger is stopped so that the movable seat portion 61 is slightly separated from the fixed seat portion 62, and the plunger is slightly moved from the gap between the movable seat portion 61 and the fixed seat portion 62. The liquid leaks to the suction side passage 46.

When the discharge pressure approaches the P ₄ point past the P ₃ points, pressure reducing valve 66 fully open is shifted in a direction to be closed by following the direction of movement against the spring 73 of the pressure receiving plunger 69. And when the set pressure (P ₄ points) is reached,
In order to maintain the set pressure, the opening area of the throttle hole 67 is selected so that only the amount corresponding to the discharge amount from the discharge hole 18 is supplied.

The electromagnetic pump 1 discharges the fluid at the set pressure from the discharge hole 18 in this manner. However, due to the fluid resistance of the nozzle and the like, the nozzle and the inside of the pump (the through holes 44, 63,
When the pressure between the high-pressure side including the plunger working chamber 6 increases, the pressure-receiving plunger 69 is displaced against the adjustment spring 73,
This displacement amount is transmitted to the pressure reducing valve 66 via the rod 68, and moves the pressure reducing valve 66 in a direction to increase the throttling action. The throttle hole 67 and the pressure reducing valve 66 reduce the flow rate and supply to the nozzle side is restricted. The discharge pressure is automatically adjusted to the set pressure. When the pressure is reduced by the pressure reducing valve 66 in this manner, the pressure in the discharge side passage 63 downstream of the discharge valve 11 increases, and the flow rate supplied through the discharge valve 11 decreases. Since the internal pressure increases, the increase in the pressure appears as an increase in the resistance of the electromagnetic plunger 3 to the upper holding spring 4. For this reason, the return stroke amount of the electromagnetic plunger 1 decreases, so that the displacement (stroke) amount of the piston 7 also decreases, the work amount also decreases, and the suction amount decreases.

Conversely, when the pressure between the discharge hole 18 and the plunger working chamber 6 drops, the balance with the pressure adjusting spring 73 that presses the pressure receiving plunger 69 is broken, and the pressure adjusting plunger 69 is pressed by the pressure adjusting spring 73.
To move the pressure reducing valve 66 in a direction to loosen the throttle action, and as a result, the pressure in the pump chamber 9 decreases as a result of an increase in the flow rate supplied through the discharge valve 11 in order to increase the flow rate. The downward stroke of the piston 7 by the holding spring 4 will increase. Therefore, the discharge pressure is automatically adjusted to a set pressure (for example, 7 kg / cm ² ) because the work amount increases and the pressure increases. Thus, the stroke of the piston is determined in comparison with the discharge amount (work amount), so that it can be minimized and can contribute to reducing the pulsation of the discharge pressure, the vibration of the pump itself, and the vibration noise in a steady state. It is.

It should be noted that comparing FIG. 10 of a characteristic diagram obtained from the characteristics of the present invention in the synchro range with FIG. 11 of a characteristic diagram provided with a conventional relief valve, the stroke amount of the pump is reduced. It turns out that it is extremely small after the set pressure, and the pulsation is reduced. The pressure applied to the pressure rise time adjusting mechanism 23 is the discharge pressure (the downstream pressure of the discharge valve 11).
Since the pressure is not regulated by the pressure reducing valve,
This is a high value of about 4 kg / cm ² , which is applied to the plunger 32, so that the minute leak amount Δq leaking to the suction side in the pressure rise time adjusting mechanism can be reduced. If this is explained based on FIG. 12, the total piston discharge amount of the electromagnetic pump having the pressure rise time adjusting mechanism using the relief valve is expressed by the following equation (1): Q = Q ₇ + Q _R + q ₇ Equation (1) In the present invention, equation (2) is obtained.

_{Q = Q 7 + q 10 ...} (2) Equation however, Q ₇ is the amount discharged from the discharge hole 18, with the amount of leakage Q _R return, 2 times 1.5 times normal Q _7, a q _7> q _10.

From the above, in the characteristics of the invention, Q _R component is eliminated completely, in which the effect of reducing the operating stroke of the piston.

Enlarging the ratio of the diameter D ₁ of the side facing the D ₂ and the low pressure side chamber 43 on the side facing the high pressure side chamber 42 of the plunger 39 of the aforementioned pressure increase time adjustment mechanism 23, i.e., if a larger pressure receiving area ratio, fine It is also possible to set the leak amount Δq to “0”. In this case, as shown by the minute leak amount Δq ′ line (FIG. 12), the point at which the leak amount is zero must be determined between 7 kg / cm ² and 10 kg / cm ² . Because, when the power supply to the electromagnetic pump stops, the piston 7 also stops, and the solenoid valve 16 closes.
The pressure reducing valve 66 moves in the opening direction from the decrease of the internal pressure, and the pressure of the high pressure side chamber 42 of the pressure rising time adjusting mechanism 23 also suddenly increases to approximately 7 kg /
While being lowered to about cm ^2, in that case, plunger 39
This is because the return force by the pressing spring 50 for pressing the pressure must be greater. By doing so, the plunger 39 is returned when the pump is stopped, and can be dealt with when restarting.

The discharge pressure is adjusted by rotating the pressure adjusting screw 75, whereby the discharge pressure can be adjusted to an arbitrary set pressure. However, the maximum capacity of the electromagnetic pump, that is, the adjustment within the maximum discharge pressure of each used nozzle, is performed. Needless to say, the pressure range.

Further, in the present invention, since the elastic member 71 such as an O-ring is interposed in the gap between the pressure receiving plunger 69 and the cylinder 70, almost no fluid leaks to the chamber 72 on the side opposite to the pressure reducing valve. The pressure receiving plunger 69 may be loosely and slidably inserted into the cylinder 70 without being provided.

(Effects of the Invention) As described above, according to the present invention, the rise characteristic of the discharge pressure in the initial stage of pump startup is sharply increased to near the ignition point, and the pressure is gradually increased before and after the ignition point to make the non-combustible discharge oil In addition to obtaining effects such as reducing outflow and ignition noise, the required discharge amount can be adjusted by adjusting the pressure using a pressure reducing valve provided in the middle of the passage downstream of the discharge valve. It is possible to reduce the pulsation of the discharge pressure in the steady state because it is made to move with the minimum necessary stroke amount that matches the (spray amount), and it is also possible to reduce the vibration and noise of the electromagnetic pump itself and also the combustion noise It is.

Also, during steady operation (set pressure), a discharge pressure higher than the set pressure of the pump is applied to the pressure rise time adjusting mechanism, so that the pressing force on the plunger is increased and the minute leak amount can be further reduced to the minimum. . Further, by increasing the pressure receiving area ratio on both sides of the plunger 39, the leak amount can be set to “0” during the set operation. This can also contribute to a reduction in the piston stroke.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an embodiment of the present invention, FIG. 2 is a transverse sectional view of the same, FIG. 3 is a sectional view of a pressure rise time adjusting mechanism, FIG. FIGS. 6 to 8 are sectional views showing an operation state of a pressure rise time adjusting mechanism. FIG. 9 is a sectional view of an electromagnetic pump of the present invention having a pressure rise time adjusting mechanism. Characteristic diagram, No.
FIG. 10 is a pressure characteristic diagram of a pressure rise time adjusting device employing a conventional relief valve, FIG. 11 is a pressure characteristic diagram of the present invention, and FIG. 12 is a PQ characteristic of pressure and flow characteristics of the present invention. FIG. 2 ... electromagnetic coil, 7 ... piston, 9 ... pump room,
10 …… Suction valve, 11 …… Discharge valve, 29 …… Cylinder, 39 ……
Plunger, 42 …… High pressure side chamber, 43 …… Low pressure side chamber, 50 ……
Main spring, 53, orifice, 54, first valve, 60, second valve, 66, pressure reducing valve, 69, pressure receiving plunger, 70, other cylinder, 72, anti-pressure reducing valve side Room, 76
…… Return passage.

Claims (1)

(57) [Claims] 1. A piston 7 is reciprocated by intermittent energization of an electromagnetic coil 2 to change the volume of a pump chamber 9.
An electromagnetic pump that sucks liquid from the suction hole 12 and pressurizes and pumps the liquid through the discharge hole 18 through the solenoid valve 16 for the cooperation between the suction valve 10 and the discharge valve 11 due to the volume change of the pump chamber 9. The plunger 39 is slidably inserted into the cylinder 29 to partition the inside of the cylinder 39 into a high-pressure side chamber 42 and a low-pressure side chamber 43 connected to a discharge side downstream of the discharge valve 11. Concubine
The low pressure side chamber 43 communicates with the low pressure side chamber 43 through an orifice 53 formed in the plunger 19, and the plunger 39 is moved by the main spring 50 disposed in the low pressure side chamber 43.
42, until the movement of the plunger 29 due to the increase in the pressure of the high pressure side chamber 42 exceeds a predetermined value.
A first valve 54 for shutting off communication between the low-pressure side chamber 43 and the low-pressure side chamber 43 is provided, and the low-pressure side chamber 43 and the suction-side passage are kept until the movement of the plunger 39 due to an increase in the pressure of the high-pressure side chamber 42 becomes maximum. And a pressure rise time adjusting mechanism 23 provided with a second valve 60 for restricting the communication between the low pressure side chamber 43 and the suction side passage 46 when the pressure becomes maximum. A pressure reducing valve 66 for reducing the flow rate flowing through the passage is provided on the passage between the discharge port 18 and the pressure reducing valve 66, and the pressure reducing valve 66 is displaced by a pressure receiving plunger 69 to which the discharge side pressure is applied. A pressure regulating spring 73 is disposed slidably in another cylinder 70 provided separately from the cylinder 29, and in a chamber 72 on the side opposite to the pressure reducing valve with the pressure receiving plunger 69 of the other cylinder 70 interposed therebetween. Communicates with the suction side passage of the electromagnetic pump to the chamber 72 on the side opposite to the pressure reducing valve. An automatic pressure regulating type electromagnetic pump having a pressure rise time adjusting mechanism, comprising a pressure adjusting mechanism 65 having a return passage 76 formed therein.