JP2000240561A - Solenoid pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the stability of a delivery quantity at the time of idle start and the stability of a delivery quantity under the change of an intake pumping by arranging an air chamber wherein the gravity direction communicates with a suction flow path and the other direction is air-tightly, on a solenoid pump for supplying liquid to the outside with motion in the delivery direction of a plunger. SOLUTION: In a solenoid pump, the suction inlet 10 side is connected to a tank, and the delivery port 7 side is connected to the feed side. In the case of an operation, current pulse is applied to a solenoid coil 1, a fluid in a pump chamber 26 is pressurized at the time of reciprocating motion of the delivery port 7 direction of a plunger 15, and a check valve 12 is pushed and opened to deliver from the delivery port 7. Simultaneously, the fluid in the suction flow path is pulled up by negative pressure, and accumulatingly energized by energizing means which consists of support springs 21, 22. At the time of reciprocation of the plunger 15, the fluid in the tank is sucked in the pump chamber 26. In this case, an air chamber 30 which communicates with an intake flow path 27 at a communicating part 31 of the gravity direction and which is air-tightly formed in the other direction, is arranged and pressure change generated in the intake flow path 27 is buffered.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic pump used for a variety of liquid supply applications such as a fuel supply application for a combustion device used for heating, hot water supply, cooking, etc., and a cleaning liquid supply application for a cleaning device.

[0002]

2. Description of the Related Art [Basic Configuration and Operational State] This type of electromagnetic pump has a tubular body that forms a liquid flow path from a suction port to a discharge port through a suction flow path, a pump chamber, and a discharge flow path. An electromagnetic coil for moving the plunger forward, including at least two valves, a plunger provided in a reciprocating state inside the cylindrical body, and a check valve provided at the inlet of the pump chamber and a check valve provided at the outlet of the same chamber. And a biasing means for returning the plunger, wherein the liquid in the discharge flow path is supplied to the outside from the discharge port by the movement of the plunger in the discharge direction, and the liquid is sucked into the suction flow path from the suction port. Become.

When using this electromagnetic pump, the suction port is connected to the liquid of a liquid supply source such as a tank, and the discharge port is connected to the liquid supply destination directly or via an extension pipe. A pump function is provided by placing the mouth at a lower position and setting the tubular body in a substantially upright state, and supplying driving power consisting of intermittent pulse power to the electromagnetic coil upon driving, and causing the plunger to reciprocate. At the start of the first drive after the installation of the pump, the liquid flow path inside the pump is in a state of being filled with air, so the reciprocating motion of the plunger is in an idling state. Is pushed out to the discharge side, a negative pressure is generated in the suction flow path to suck up the liquid of the supply source, the inside of the pump is replaced with the liquid, and then the liquid is discharged from the discharge port. In stopping the driving, by stopping the supply of the driving power, the reciprocating motion of the plunger is stopped, and the liquid discharge is stopped. While the driving is stopped, the liquid inside the pump is preserved by the action of the check valve, and the operation state is such that the liquid is immediately discharged without the idling operation at the time of re-driving. However, if special conditions are given, such as when the installed electromagnetic pump is removed and reinstalled while the drive is stopped, or when the liquid in the tank is depleted and the end of the suction channel is exposed to the air, The liquid in the pump may be replaced with air again, and when the driving is started from such a state, the operation state starts from the idling state as in the first use. The operation starting from the idle hit state is particularly called an idle hit start.

When using this kind of electromagnetic pump as a part of a mass production apparatus, each pump applies one or more kinds of predetermined driving power under predetermined use conditions. It is required to be excellent in quality to realize a predetermined discharge amount and to be excellent in cost required for the pump itself and related parts. To satisfy this requirement,
Reproducibility of discharge characteristics of individual pumps, uniformity of discharge characteristics between individual pumps, tolerance for pump operating conditions,
Power saving required for driving the pump is required.

[0005] The reproducibility of the discharge rate characteristics of the individual pumps described above requires reproducibility in which, when the discharge rate of one pump is measured a plurality of times under constant conditions, the measurement result shows a substantially constant discharge rate. It is not suitable for practical use if it shows measurement results that differ greatly each time. The above-mentioned uniformity of the discharge amount characteristics among the individual pumps requires uniformity in which a measurement result obtained by measuring the discharge amounts of a plurality of pumps belonging to the same quality under a constant condition shows a substantially constant discharge amount. Irrespective of the pumps described above, it is not suitable for practical use if the discharge amount differs greatly for each pump. The above-mentioned tolerance for the operating conditions of the pump requires that the change in the discharge amount due to the change in the operating conditions given to the pump is sufficiently small.For example, the difference in the suction head within the allowable range given in practical use causes the discharge amount to vary. It does not fit practical use if it changes greatly. The above-described power saving of the driving power directly affects the power capacity and cost of the electromagnetic coil of the pump and the pump driving power supply unit.

The above-mentioned prior art relating to the reproducibility of the discharge amount is based on the design means of installing an orifice in the discharge flow path of the electromagnetic pump. It is a technology that has improved the problems that have fallen. Regarding the uniformity of the discharge rate characteristics between the individual electromagnetic pumps described above, it is originally required to satisfy the required uniformity by the quality incorporated in the pump manufacturing process, but an orifice is installed in the discharge flow path. As a result, the dimensional error and the surface roughness error of the orifice itself affect the ejection amount very sensitively, resulting in a deterioration in the uniformity of the ejection amount characteristic. In order to ensure the required uniformity for this purpose, a step of adjusting the discharge amount for each individual pump is required. This adjustment step includes, for example,
As disclosed in Japanese Patent Publication No. 7-101033 "Method of manufacturing electromagnetic pump for fuel supply of petroleum combustor",
Measure the discharge volume before adjustment of the pump once manufactured to a larger discharge amount individually, select a fixed resistor with a resistance value according to the magnitude of the deviation between this discharge amount before adjustment and the target discharge amount, and A technology that achieves the desired discharge rate by installing it in series with the coil, achieving the desired uniformity,
This is a complicated and time-consuming technique. The above-described tolerance regarding the operating conditions of the pump is a conventional technique having the effect of reducing the change in the discharge amount due to the change in the suction head by the technique of installing the orifice in the discharge flow path at the same time. Regarding the power-saving property of the drive power related to the above, the provision of the orifice in the discharge flow path caused a large increase in drive power particularly in a region where the suction lift is small. To summarize the above prior art, the effect corresponding to the above was obtained by installing an orifice in the discharge flow path, but the power required to obtain a constant discharge amount was increased, and the size and surface roughness of the orifice itself were increased. A slight error such as a degree causes a drawback that an extremely large discharge amount error occurs.Therefore, it becomes necessary to increase the power capacity of the electromagnetic coil and the drive power supply unit, and the uniformity of the discharge amount among the individual pumps is deteriorated. A special discharge amount adjustment process was required, resulting in a decrease in production efficiency and a sharp rise in cost.

[Conventional Example 1] Conventional Example 1 is a conventional example of the most basic type of this type of electromagnetic pump, and FIG. 11 is a longitudinal sectional view showing the structure of Conventional Example 1. 91 is an electromagnetic coil, 92 is an input terminal of the electromagnetic coil 91, 93 is a magnetic path, and 94 and 95 are a pair of magnetic poles. Reference numeral 96 denotes a cylindrical body in which a discharge cylinder 98 having a discharge port 97, a cylinder 99, and a suction cylinder 101 having a suction port 100 are integrally formed. 102 is a check valve, 1
03 is a valve seat of the check valve 102; 104 is a valve spring of the check valve 102; 105 is a plunger;
06, check valve 107, valve seat 108, valve spring 109
And the valve seat 103 and the seat 1 in the cylinder 99.
Between them, they are equilibrium supported by a pair of support springs 111 and 112, and are held in a reciprocable state. 113
And 114 are O-rings and 115 is a filter. 116
Is a pump chamber, the check valve 107 forms an inlet of the pump chamber, and the check valve 102 forms an outlet of the pump chamber 116. Reference numeral 117 denotes a suction flow path formed on the suction port side of the pump chamber 116, 118 denotes a discharge flow path formed on the discharge port side of the pump chamber 116, and 119 denotes a liquid flow path. Road 118.

[Conventional Example 2] In Conventional Example 2, an orifice is added to the discharge flow path of Conventional Example 1 to increase the flow path resistance in this portion, so that the amount of change in the discharge amount at the start of idling is increased. This is a conventional example in which the characteristic of the discharge amount change due to the change of the suction lift is flattened while reducing the suction amount. FIG. 12 is a longitudinal sectional view showing the configuration of the conventional example 2. The configuration of Conventional Example 2 will be described focusing on the parts changed from Conventional Example 1. An orifice 120 is provided in discharge passage 118. The description of other parts is omitted because they are the same as in the first conventional example.

[0009]

In the electromagnetic pump of the prior art 1 which is a basic type of the prior art, the reproducibility of the discharge amount at the time of idling is poor, and the discharge amount of the individual pump is not determined. Even if the adjustment for the uniformity of the discharge amount is performed, there is a drawback that the adjustment accuracy is poor and the change in the discharge amount due to a change in the suction head is large. . In Conventional Example 2 in which an orifice was added to the discharge flow path to improve this drawback, the reproducibility of the discharge amount at the time of idling was improved to a practically acceptable level, but the size and surface roughness of the orifice were reduced. Since a slight error in the above-mentioned method causes a large ejection amount error very sensitively, an ejection amount adjustment process for uniformity of the ejection amount is required. The orifice installation also significantly flattened the discharge volume change characteristics due to the suction head change, but on the other hand, reduced power efficiency and required measures to increase the power capacity of the electromagnetic coil of the pump and the drive power supply circuit, resulting in a significant cost increase. Soaring. In the present invention, the above-mentioned drawbacks are improved, the error of the discharge amount occurring during the idling is eliminated, the reproducibility of the discharge amount is improved, and the use condition, for example, the change of the suction head due to the liquid level change in the tank. To provide a high-quality electromagnetic pump that achieves a significant reduction in cost by reducing the rate of change of the discharge amount due to the above, simultaneously improving the power efficiency, and eliminating the cause of the deterioration of the uniformity of the discharge amount. . In addition, this kind of electromagnetic pump has a drawback that since the pump operation is caused by the reciprocating movement of the plunger, the vibration noise accompanying this movement is brought to the outside.

[0010]

SUMMARY OF THE INVENTION An electromagnetic pump according to the present invention comprises: a tubular body forming a liquid flow path from a suction port to a discharge port via a suction flow path, a pump chamber, and a discharge flow path; An electromagnetic coil for reciprocating the plunger, a check valve provided at the pump chamber inlet and a check valve provided at the chamber outlet, and at least two valves for moving the plunger forward and backward; An electromagnetic pump having a biasing means for returning the plunger, supplying liquid in the discharge flow path to the outside from the discharge port by movement of the plunger in the discharge direction, and sucking the liquid from the suction port into the suction flow path. In addition, an air chamber having a gravity direction communicating with the suction flow path and an airtight structure in the other direction is provided (claim 1).

An electromagnetic pump according to the present invention is the above-described electromagnetic pump, wherein the biasing means has a pair of coil springs press-fitted on the discharge port side and the suction port side of the plunger. (Claim 2).

An electromagnetic pump according to the present invention is the above-described electromagnetic pump, wherein an orifice (a narrow flow path) is provided between a suction position and a communication position where an air chamber communicates with a suction flow path. (Claim 3).

An electromagnetic pump according to the present invention is the above-described electromagnetic pump, wherein the urging means comprises a coil spring press-fitted on the discharge port side of the plunger, and an end of the plunger on the suction port side. The abutting portion with which the end of the plunger abuts constitutes a closing valve that closes the liquid flow path at the plunger stop position and opens the same flow path at the plunger movement position. 4).

An electromagnetic pump according to the present invention is the above-described electromagnetic pump, wherein the urging means comprises a coil spring press-fitted on the suction port side of the plunger, and an end of the plunger on the discharge port side. The abutting portion with which the end of the plunger abuts constitutes a closing valve that closes the liquid flow path at the plunger stop position and opens the same flow path at the plunger movement position. 5).

The electromagnetic pump according to the present invention is the above-described electromagnetic pump, wherein a check valve provided at a pump chamber inlet is integrally formed with the plunger, and a check valve provided at the pump chamber outlet is provided with the cylindrical valve. It is characterized by being integrally formed with the body (claim 6).

The electromagnetic pump according to the present invention is the above-described electromagnetic pump, wherein a check valve provided at an inlet of the pump chamber is formed integrally with the cylindrical body, and a check valve provided at an outlet of the pump chamber is provided as the above. It is characterized by being integrally formed with the plunger (claim 7).

[0017]

The theoretical discharge amount of this type of electromagnetic pump is represented by the product of the stroke length, the number of reciprocating movements, and the efficiency determined by the balance between the cross-sectional area of the plunger, the plunger power and the load. The efficiency is a ratio obtained by subtracting a loss caused by backflow of the clearance between the plunger and the cylinder. Among them, the cross-sectional area of the plunger, the plunger power, and the number and efficiency of the reciprocating motion are constant as long as the individual pump and the drive power supply condition are specified. Therefore, the fluctuation of the discharge amount generated within this range is caused by the fluctuation of the load. .

[Analysis Results of Improving Effect of Insufficient Stability Failure in Conventional Example] With respect to the electromagnetic pump of Conventional Example 1, the results of the discharge amount measurement performed under the condition of no emptying hold other conditions constant. As long as the results show a nearly constant discharge rate measurement, the liquid flow path inside the pump is temporarily replaced with air,
When a blank shot start is performed, a sudden change in the discharge amount measurement result may be shown in spite of the same specimen. The discharge amount error that occurs only during idling is improved by the electromagnetic pump of Conventional Example 2 in which an orifice is provided in the discharge passage. However, the driving power required to obtain a constant discharge amount was increased by this improvement means.

In the study leading to the present invention, as a result of engineeringly examining the cause of the poor hitting stability in Conventional Example 1,
It has been found that the cause of the discharge amount error occurring at the time of the start of the blanking is that the presence or absence and the size of the air bubbles interposed in the suction passage change at the opportunity of the start of the blanking. Some of these bubbles are transient bubbles that are discharged from the discharge port in a short time due to the buoyancy of the bubbles themselves and the flow of the liquid.However, bubbles that have entered the stagnation portion of the flow path or bubbles that have adsorbed to the solid surface , Resulting in stagnant bubbles staying at the same position for a long time. In this type of electromagnetic pump, when the plunger moves in the discharge direction,
It performs the work of pushing up the liquid in the discharge flow path and the work of pulling up the liquid in the suction flow path.If air bubbles are present in the suction flow path, the bubbles expand due to the negative pressure generated in the suction flow path due to the movement of the plunger. Due to this expansion, a part of the work of sucking the liquid in the suction passage is reduced, and the stroke length of the plunger corresponding to the reduction of the load is increased to increase the discharge amount. Once expanded, the bubbles return to their original volume in different time zones. At this time, the reduced liquid suction in the suction channel is compensated for, and the same action is repeated as long as the bubbles stay. Since the intervening bubbles are extremely small,
The discharge amount error generated in one stroke is only a very small amount, but the discharge amount error in which the same operation is continued for a long time is accumulated for the number of strokes, and a discharge amount error corresponding to the presence and size of bubbles is generated. When the bubble state suddenly changes at the time of the idling start, the discharge amount suddenly changes.

In the prior art 2, an orifice was provided in the discharge flow path to improve the poor hitting stability. However, the orifice provided in the discharge flow path is a fixed load to the plunger stroke, and Bubbles interposed in the flow path mean a fluctuating load, and by setting the magnitude of the fixed load sufficiently large with respect to the magnitude of the fluctuating load, the effect of reducing the influence of the bubbles on the discharge amount can be obtained. In addition, the change in the ejection amount due to the change in the bubble state occurring at the time of the start of the blanking is reduced proportionally, and the poor blanking stability is improved. However, when the fixed load is set sufficiently large, it is necessary to increase the driving power required to obtain a constant discharge amount, and the power efficiency is reduced.

[Effect of Improving Power Efficiency in the Present Invention] The effect of improving the power efficiency of the electromagnetic pump of the present invention will be described. In the electromagnetic pump of the present invention, an air chamber is provided in the suction passage. When the plunger moves in the direction of the discharge port, the air in the air chamber expands due to an increase in the negative pressure generated in the suction flow path, thereby reducing a part of the work of lifting the liquid in the suction flow path. The reduced work is a time zone in which the plunger moves in the direction of the suction port, the air volume is restored, and the reduced work is compensated. The reduction in the amount of work due to this effect
That is, the load is reduced, whereby the stroke length of the plunger is increased, and the discharge amount is correspondingly increased. The relationship between the amount of air in the air chamber provided in the suction passage and the amount of increase in the amount of discharge shows a characteristic that the amount of change in the amount of discharge increases in accordance with the amount of air and converges toward the saturation point of the air amount effect. This characteristic is shown in FIG. 13 in the "Relationship curve between air amount and discharge amount".
As shown. This curve shows the relationship between the amount of air in the air chamber provided in the suction passage and the amount of discharge under a certain amount of driving power. Indicates that the power required to obtain a constant discharge amount decreases, and by setting the air amount sufficiently large, the effect of the error of the air amount on the discharge amount error is extremely small. Indicates that it can be done.

[Improvement of Defects in Rapid Change of Discharge Amount at Start of Idling] Next, improvement of the phenomenon that the discharge amount changes suddenly at the start of idling will be described. This phenomenon is a change in the discharge amount due to the presence / absence and the size of the bubbles in the suction flow path being not constant. In an electromagnetic pump without an air chamber (for example, Conventional Example 1), the change in the discharge amount when air bubbles of a certain size intervene in the suction flow passage is the same as that in the electromagnetic pump of the present invention (for example, Example 1). FIG. 13 shows a change in the discharge amount when the air bubbles are interposed. In the drawing, a discharge amount error A occurs between a case where air bubbles having the air amount Q1 intervenes in a pump having no air chamber and a case where air bubbles do not intervene. On the other hand, in a pump provided with an air chamber having an air amount QX, bubbles of the same size (air amounts Q2, Q1 =
A discharge amount error B occurs when Q2) intervenes and when it does not intervene. A discharge amount error B occurring in a pump having an air chamber is substantially smaller than a discharge amount error A occurring in a pump having no air chamber. Similarly, if the presence and absence of air bubbles and the size change variously,
For all air volume settings, the magnitude of the discharge error that occurs in the pump with the air chamber is
It is understood that the discharge amount error is small with respect to the magnitude of the discharge amount error generated in the pump having no air chamber, and it is understood that the discharge amount error can be improved with a large difference by setting the air amount of the air chamber sufficiently large.

[Effect of Flattening of Change in Discharge Amount Due to Change in Suction Head in the Present Invention] The air chamber of the suction flow passage installed in the electromagnetic pump of the present invention has a negative pressure generated in the suction flow passage when the plunger moves in the discharge direction. The pressure causes the air in the air chamber to expand, and this expansion reduces a part of the work of drawing up the liquid in the suction passage, and the stroke length of the plunger increases accordingly. Once expanded, the bubble returns to its original volume in the delayed time zone, and the same action is repeated for each discharge stroke, so that the plunger stroke length is maintained continuously for each stroke, realizing the effect of increasing the discharge amount. I do. The effect of this effect is that when the suction head is small, the work of pulling up the liquid in the suction flow path is small, so that the effect of increasing the discharge amount is small. However, the effect of increasing the discharge amount is expanded according to the change of the suction head. This has the effect of flattening the change in the discharge amount due to the change.

For reference, in the orifice installed in the discharge channel of the conventional example 2, the larger the flow rate of the liquid passing through the orifice, the larger the differential pressure between both ends of the orifice, and the greater the effect of reducing the discharge amount. This prior art also has an effect of flattening a change in the discharge amount due to a change in the suction head.
However, while the prior art has a function of flattening in a direction to reduce the discharge amount under a constant driving power, the present invention technology has a function of flattening in a direction to increase the discharge amount under a constant power. None, this difference in direction of action constitutes a source of power efficiency differences between the two technologies.

[Vibration Noise Reduction Function of the Present Invention] In this type of electromagnetic pump, the liquid is intermittently sucked and discharged by the reciprocating motion of the plunger, so that the vibration noise is transmitted or radiated to the outside. However, in the electromagnetic pump of the present invention, the air in the air chamber installed in the suction passage absorbs and reduces the vibration noise and transmits or radiates the noise to the outside. The effect is to reduce. In addition, separately, an electromagnetic pump in which a gas damper is installed in the discharge channel has been proposed,
By installing an air chamber or a gas damper means in each of the suction flow path and the discharge flow path, higher effects can be obtained.

[Other Actions of the Present Invention] In the electromagnetic pump of the present invention, the direction of gravity communicates with the suction flow path.
An air chamber whose buoyancy direction is airtight is installed. By designing the volume of the air chamber to be sufficiently large, the dimensional error of the air chamber itself, the inclination of the installation position of the pump, and the discharge amount error caused by the error of the air amount due to air bubbles mixed during blanking are reduced to practically negligible. can do. In addition, at the time of start of idling of the electromagnetic pump, air is automatically arranged in the air chamber, and liquid is automatically arranged in the liquid flow path, so that a special distribution function configuration is not required. Since the air in the air chamber and the liquid in the liquid flow path communicate directly with each other, and the position of the communication surface is not fixedly limited, when the air volume of the air chamber changes due to environmental temperature and liquid temperature, Even in the case where the pump is inclined to the degree that is practically allowable due to the inclination of the device, for example, an appropriate communication surface position is automatically configured in each situation, and the operation function is not impaired. In addition, since the air chamber has a configuration in which there are no moving parts or parts, the functionality of the air chamber is not affected by vibration characteristics such as resonance of the moving parts, inertia characteristics such as responsiveness, and It is hard to cause troubles such as breakdowns. There is almost no cost increase due to the installation of the air chamber, cost reduction by eliminating the orifice of the discharge flow path, cost reduction by reducing the power capacity of the electromagnetic coil to obtain a constant discharge amount, power of the drive power supply unit A large reduction in cost can be realized by a reduction in cost due to a reduction in capacity, a reduction in cost due to the elimination of a discharge amount adjustment step, and the like.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the electromagnetic pump according to the present invention will be described with reference to the drawings. However, the present invention is not limited to the embodiments described below, and The present invention can be implemented in various types of electromagnetic pumps that can easily understand that the operation can be effectively realized.

[Embodiment 1] Embodiment 1 is an embodiment in which an air chamber communicating with a suction flow passage is installed in the electromagnetic pump of Conventional Example 1, and a longitudinal sectional view thereof is shown in FIG. 1 is an electromagnetic coil, 2 is an input terminal of the electromagnetic coil 1, 3 is a magnetic path, and 4 and 5 are a pair of magnetic poles. Reference numeral 6 denotes a cylindrical body, which is integrally formed with a discharge cylinder 8 having a discharge port 7, a cylinder 9 and a suction cylinder 11 having a suction port 10. 12 is a check valve, 13 is a valve seat of the check valve 12, 1
Reference numeral 4 denotes a valve spring of the check valve 12, which is integrally formed with the cylindrical body 6. 15 is a plunger, and the plunger body 1
6. The check valve 17, the valve seat 18, and the valve spring 19 are integrally formed. A support spring 21 is press-fitted between the plunger 15 and the valve seat 13, a support spring 22 is press-fitted between the plunger 15 and the receiving seat 20, and the plunger 15 reciprocates between the pair of support springs 21 and 22. It is equilibrium supported in a possible state. When a pulse of driving power is input to the electromagnetic coil 1, the plunger 15 moves forward in the direction of the discharge port, and the support springs 21 and 2 generated at this time move forward.
2 is configured to return when the driving power pulse ends at the end of the non-equilibrium state of the pair of support springs 21.
And 22 constitute an urging means for moving the plunger 15 back. 23 and 24 are O-rings, and 25 is an O-ring holder. Reference numeral 26 denotes a pump chamber. The check valve 17 integrated with the plunger 15 forms an inlet of the pump chamber, and the check valve 12 integrally formed with the tubular body 6 forms an outlet of the pump chamber. . Reference numeral 27 denotes a suction flow path formed on the suction port side of the pump chamber 26, reference numeral 28 denotes a discharge flow path formed on the discharge port side of the pump chamber 26, and reference numeral 29 denotes a liquid flow path.
And a discharge channel 28. Numeral 30 denotes an air chamber, which communicates with the suction flow path 27 through a communication part 31 in the direction of gravity, and has a space formed airtight by a solid wall surface and an O-ring 24 in the other direction.
Reference numeral 32 denotes a filter which is installed at the suction port 10 to prevent intrusion of solid matter. The electromagnetic pump according to the first embodiment is used with the suction port 10 at the lower position, the discharge port 7 at the upper position, and the tubular body 6 installed in a substantially upright posture.

FIG. 2 is a distribution explanatory view showing a state where the liquid is filled in the liquid flow path 29 and the air is held in the air chamber 30 during the pump operation of the first embodiment. The area where air was distributed was shown in white. The distribution of the liquid to the liquid flow path 29 and the air chamber 30
Is automatically performed at the time of start of idle driving, this arrangement is maintained thereafter, and is performed again at the start of next idle driving. The air held in the air chamber 30 directly receives a pressure change generated in the suction passage 27 by the reciprocating motion of the plunger 15 from the communication portion 31 and performs a corresponding volume change.

The electromagnetic pump according to the first embodiment is installed in the above-described upright position, and the suction port 10 is directly immersed in a liquid supply source, for example, a liquid in a tank, or an extension pipe extending from the suction port 10. The terminal port is immersed in the liquid of the supply source, and at the same time, the discharge port 7 is provided directly or an extension pipe extending from the discharge port 7 is installed toward the supply destination. When the pump operates, a driving power pulse is supplied to the electromagnetic coil 1 through the input terminal 2 so that the plunger 15 is sucked in the direction of the discharge port 7 by the electromagnetic force generated in the electromagnetic coil 1. The forward movement of the plunger causes the pump chamber 26
Is reduced, the internal fluid is pressurized, the check valve 12 is pushed open, and discharged in the direction of the discharge port 7. Simultaneously with this, a negative pressure is generated in the suction flow path, and the fluid in the suction flow path is pulled up and stored in the urging means including the support springs 21 and 22.
Then, at the end of the driving power pulse, the plunger 15 is moved by the restoring force of the support springs 21 and 22 into the suction port 10.
As a result, the volume of the pump chamber 26 increases, a negative pressure is generated in the pump chamber, and the check valve 17 is opened to suck the fluid in the direction of the suction port into the pump chamber. By repeatedly supplying the driving power pulse, the reciprocating motion of the plunger 15 can be continuously repeated, and the supply liquid can be repeatedly discharged and supplied toward the supply destination.

In practical use of this electromagnetic pump, there are both a case where the internal fluid in the liquid flow path 29 at the start of operation is air and a case where the internal fluid is liquid. In the case where the internal fluid is air, when the electromagnetic pump is operated from the virgin state, when the supply liquid is depleted and the liquid inside the liquid flow path is replaced with air together with the liquid discharge, the electromagnetic pump is once removed from the installation part This case corresponds to the case where the internal liquid has flowed out, and for a while after the start of the operation, the internal air is discharged in the direction of the discharge port by the pump operation to generate a negative pressure in the suction flow path 27, As a result, the liquid is sucked in from the suction port direction, the fluid in the liquid flow path 29 is replaced with the liquid from the air, and then the liquid is discharged from the discharge port 7. At this time, the air in the air chamber 30 is stored without being replaced by the liquid, and the liquid is automatically distributed to the liquid flow path and the air is automatically distributed to the air chamber. In the case where the internal fluid of the liquid flow path 29 is liquid at the start of the operation, the electromagnetic pump stops driving in the liquid discharge state, and the liquid in the liquid flow path flows backward due to the check action of the check valve during the stop. Such a case corresponds to this case, for example, when the liquid is held without being discharged and then re-driven after a while, and the liquid is discharged from the beginning of the driving without the air discharging behavior. Also in this case, the air in the air chamber 30 is stored without being lost.

FIG. 3 shows the electromagnetic pumps according to the first embodiment, the prior art examples 1 and 2, and a DC 24 V pulse time of 2.1 ms.
ec is test data of the discharge amount / suction head characteristic, which was driven by the intermittent pulse power switched to the frequency of 30 Hz and performed with the same supply liquid. The first embodiment differs from the first and second conventional examples in that an air chamber 30 is provided in the suction passage.
In FIG. 3, the solid line indicates the case where the specimen is the embodiment 1, the broken line indicates the case of the conventional example 1 (without orifice, no air chamber), and the dashed line indicates the case of the conventional example 2 (with orifice, no air chamber). Tables 1 and 2 are compiled for easy understanding of the magnitude of the change in the discharge amount due to the change in the suction head and the discharge amount at the same drive power. Table 3 shows the results of measurement of the discharge amount in each of the six times of the idling start, and the difference between the maximum value and the minimum value as a variation width.

[Table 1]

[Table 2]

[Table 3] From Table 1, it can be seen that in the discharge amount change characteristic due to the change of the suction head, the first embodiment is remarkably superior to the first conventional example, and shows substantially the same level of characteristics as the second conventional example in which the orifice is provided in the discharge passage.
From Table 2, it can be said that the power efficiency of the first embodiment is greatly improved over the first and second conventional examples. Table 3 shows that the idle hitting stability of Example 1 was slightly higher than that of Conventional Example 2 and significantly improved that of Conventional Example 1. As described above, Example 1 showed test results that greatly improve Conventional Example 1 and Conventional Example 2 in the overall performance of discharge amount change characteristics due to suction head change, discharge amount / power efficiency, and idling stability.
In particular, the fact that the test data in which the discharge amount with the same driving power is approximately twice as large as that of the conventional example 1 and the conventional example 2 at the suction head of 120-cm is worthy of special mention in improving the power efficiency.

[Embodiment 2] Embodiment 2 is an embodiment in which an orifice is added to the electromagnetic pump of Embodiment 1. FIG. 4 is a longitudinal sectional view of the second embodiment. Reference numeral 33 denotes an orifice. This orifice is an orifice provided between a communication position where an air chamber communicates with a suction flow path and a suction port. It has an increased design. The other configuration is the same as that of the first embodiment, and the description is omitted to avoid duplication.

FIG. 5 shows the electromagnetic pumps of the embodiment 2, the conventional example 1 and the conventional example 2 applied with a direct current of 24 V and a pulse time of 2.1 ms.
ec is test data of the discharge amount / suction head characteristic, which was driven by the electric power switched to the frequency of 30 Hz and was carried out with the same supply liquid. Embodiment 2 includes an air chamber in the suction flow path,
It differs from Conventional Examples 1 and 2 in that an orifice is provided on the upstream side. In FIG. 5, the solid line indicates the case where the test piece is the embodiment 2, the broken line indicates the case of the conventional example 1 (without orifice, no air chamber), and the dashed line indicates the case of the conventional example 2 (with orifice, no air chamber). Tables 4 and 5 are compiled for easy understanding of the magnitude of the change in the discharge amount due to the change in the suction head and the discharge amount at the same drive power. Table 6 shows the results of measuring the ejection amount for each of the six times of performing the blanking start, and describing the difference between the maximum value and the minimum value as a variation width.

[Table 4]

[Table 5]

[Table 6] In the second embodiment, an orifice is installed between a communication position where the air chamber of the electromagnetic pump of the present invention communicates with the suction flow path and the suction port,
This is an embodiment in which the suction flow passage in this portion is designed to have high flow resistance. Even in such a design, in the discharge amount change characteristic due to the change of the suction head, in the discharge amount / power efficiency characteristic, and in the discharge amount stability at the time of start of idling, it is essential to the characteristic shown in the first embodiment. The advantage of the present invention, which is much better than the conventional example, is realized without any difference. In particular, the effect of flattening the discharge amount change characteristic due to the change of the suction head is superior to that of the first embodiment and the conventional example 2, and has the best performance.

[Embodiment 3] Embodiment 3 is an embodiment in which the check valve at the pump chamber inlet is formed integrally with the cylindrical body, and the check valve at the pump chamber outlet is formed integrally with the plunger. FIG. 6 is a longitudinal sectional view showing the structure of the second embodiment. Reference numeral 36 denotes a plunger, which comprises a plunger body 37, a check valve 38, a valve seat 39, and a valve spring 40 integrally formed.
And 41 are equilibrium supported. Reference numeral 42 denotes a check valve which is formed integrally with the cylindrical body 45 together with the valve seat 43 and the valve spring 44, and 46 denotes a pump chamber. The check valve 42 constitutes an inlet of the pump chamber 46, and the check valve 38 constitutes an outlet of the same chamber 46.

Other configurations, functions, effects of the air chambers, and the like are the same as those in the first embodiment, and the description is omitted to avoid duplication. It describes in.

[Fourth Embodiment] In a fourth embodiment, the support spring as the urging means is limited to the discharge side of the plunger, and a closing valve is provided at the end of the plunger on the suction port side. FIG. 7 is a longitudinal sectional view showing the structure of the fourth embodiment. Reference numeral 51 denotes a support spring press-fitted on the discharge port side of the plunger 52; 53, a closing valve provided at an end of the plunger 52 on the suction port side; Is a valve seat of the closing valve, which is integrally formed with the tubular body 55. The closing valve 53 has a configuration in which the restoring force of the pressurized support spring 51 is used as a valve closing force. The closing valve 53 strongly closes the liquid flow path 56 when the plunger 52 is stopped. Unblocks 56 and does not interfere with pump action.

The electromagnetic pump of the fourth embodiment is driven by half-wave rectified power of an AC power supply in a situation where the suction lift is large. In particular, the vibration noise caused by the pump operation often causes a problem. In order to observe the damping effect of the pressure vibration due to the installation of the air chamber, the pressure vibration generated in the liquid in the suction flow path was measured when the air chamber was installed based on the structure of the fourth embodiment and when the air chamber was not installed. Was measured. The results are shown in FIGS. 14 and 15 show the case of a pump having an air chamber, and FIGS. 16 and 17 show the case of a pump without an air chamber.
The figure shows the results of detecting pressure oscillations occurring in the liquid in the suction channel when driven by a power supply that has half-wave rectified the frequency of 50 Hz and 50 Hz, and observed with an oscilloscope at the same sensitivity. In each case, it is shown that the pressure vibration is significantly attenuated by the installation of the air chamber. Other configurations, functions, effects of the installation of the air chamber, and the like are the same as those in the first embodiment, and a description thereof will be omitted to avoid duplication, and the features of the configuration and functions of the present embodiment will be described at the end of this section. .

[Embodiment 5] Embodiment 5 is an embodiment in which Embodiment 3 and Embodiment 4 are compromised. FIG. 8 is a longitudinal sectional view showing the structure of the fifth embodiment. Reference numeral 61 denotes a support spring press-fitted on the discharge port side of the plunger 62; 63, a closing valve formed at the end of the plunger 62 on the suction port side; The valve seat 65 of the closing valve 63 is integrally formed with the plunger 62 and the pump chamber 6
A check valve 67 that constitutes the outlet of the valve 6 is a check valve that is integrally formed with the cylindrical body 68 and that constitutes the inlet of the pump chamber 66.
Other configurations, functions, effects of the air chambers, and the like are the same as those in the first and fourth embodiments. The description is omitted to avoid duplication, and the features of the configuration and functions of the present embodiment are described in this section. Write at the end.

[Embodiment 6] Embodiment 6 is an embodiment in which Embodiment 5 is configured in the reverse direction. FIG. 9 is a longitudinal sectional view showing the configuration of the sixth embodiment. Reference numeral 71 denotes a support spring press-fitted on the discharge port side of the plunger 72; 73, a closing valve formed on the discharge port side end of the plunger 72; A check valve which is integrally formed with the cylindrical body 75 and forms an outlet of the pump chamber 76, 77 is a valve seat of both the closing valve 73 and the check valve 74, and 78 is integrally formed with the plunger 72 to connect the inlet of the pump chamber 76. It is a check valve to constitute. Other configurations, functions, effects of the air chambers, and the like are the same as those in the first and fourth embodiments. The description is omitted to avoid duplication, and the features of the configuration and functions of the present embodiment are described in this section. Write at the end.

[Embodiment 7] Embodiment 7 is an embodiment of a compromise between Embodiment 3 and Embodiment 6. FIG. 10 is a longitudinal sectional view showing the structure of the seventh embodiment. Reference numeral 81 denotes a support spring press-fitted on the suction port side of the plunger 82; 83, a closing valve formed on the discharge port side end of the plunger 82; The valve seat 85 of the closing valve 83 is integrally formed with the cylindrical body 86, and the pump chamber 87 is formed.
A check valve constituting an inlet of the valve, 88 is a valve seat of the check valve 85, 8
Reference numeral 9 denotes a check valve integrally formed with the plunger 82 and forming an outlet of the pump chamber 87. Other configurations, functions, effects of the air chambers, and the like are the same as those in the first and fourth embodiments. The description is omitted to avoid duplication, and the features of the configuration and functions of the present embodiment are described in this section. Write at the end.

[Characteristics of each embodiment] The constitutional and functional characteristics of each embodiment described above are summarized as follows. In the above embodiment, the plunger is equilibrium supported by a pair of support springs (Embodiment 1, Embodiment 2, and Embodiment 3), the support spring is arranged on one side of the plunger, and the closing valve is provided on the other side. (Examples 4 to 7). In the former configuration, there is no solid or elastic collision during the entire reciprocating stroke of the plunger,
In the latter configuration, the closing valve collides with the valve seat at the final position of the return stroke. In the former case, regardless of the driving power, a wide range of driving power adjustment can be performed without generating a collision sound, and therefore, there is a feature that a wide range of discharge amount adjustment can be easily performed. If the interval time between the pulse that moves the plunger forward and the next pulse is less than the limit, the plunger goes back into the next forward movement process without causing a collision between the closing valve and the valve seat when the plunger moves back. When exceeds the limit, the closing valve collides with the valve seat every time
Each time, there is a disadvantage that a collision sound is generated. Therefore, there is a characteristic that the selection of the interval time between the pulses is limited, and is not suitable for a wide range of discharge amount adjustment. In the above embodiment, a configuration having no blocking valve (Embodiment 1, Embodiment 2, Embodiment 3)
And a configuration (Examples 4 to 7) including a closing valve. In the former configuration, the function of closing the liquid flow path when the operation of the pump is stopped is limited to the closing function of the check valve. However, the latter configuration has a strong closing function of the closing valve in addition to the check valve. In the above embodiment, a configuration in which a support spring is provided in the pump chamber (Embodiments 1, 2, 3, 4, and 6)
And a configuration in which no support spring is provided in the pump chamber (Examples 5 and 7). In the former configuration, the space for accommodating the support spring constitutes a dead space during the operation of the pump, has a low compression ratio at a constant plunger stroke, and has a small capacity to discharge air from the pump chamber at the time of an idle stroke. There is a disadvantage that it takes time to finish the idle stroke, and the limit suction lift is low. The latter structure has a small dead space, realizes a high compression ratio even with the same plunger stroke, has an excellent function of discharging air from the pump chamber, has a feature that the idle stroke is completed in a short time, and has a high limit suction lift. . There are a configuration in which the closing direction of the closing valve is the suction port direction (Examples 4 and 5), and a configuration in which the closing direction of the closing valve is the discharge port direction (Examples 6 and 7). This is a valve function that prevents the sucked-up liquid from returning to the tank when the pump operation stops.In the former configuration, the direction of the return pressure of the liquid and the direction in which the closing valve closes match, so an extremely excellent closing function is provided. However, the latter configuration has a closing function within a limit that the valve closing pressure of the support spring exceeds the liquid return pressure described above. However, in the case where the tank is installed at a high place, the function to prevent the flow of liquid moving in the discharge direction due to the head differential pressure when the pump operation is stopped.In the former configuration, the valve closing pressure of the support spring causes the head differential pressure of the liquid to decrease. It has a closing function within the limit exceeding the pressure, and the latter structure has a very excellent closing function because the valve closing direction and the head differential pressure direction match. In the configuration in which the orifice is installed between the communication position of the air chamber and the suction port (Example 2), even when the suction flow path at the orifice installation position is designed to have a different flow resistance, the essential effects of the present invention are lost. It is confirmed that the gradient of the suction lift / discharge amount characteristic can be further flattened by installing an orifice in the corresponding portion, as compared with a case where only the air chamber is installed, while confirming that the air chamber does not move.

In practical use of this kind of electromagnetic pump,
A usage method of adjusting the discharge amount by adjusting the drive power is often used. However, even in the electromagnetic pump of the present invention, the essential effects of the present invention are lost by adjusting the drive power. In addition, the discharge amount can be adjusted.

[0044]

Since the electromagnetic pump of the present invention has a structure in which an air chamber is provided in the suction passage, as described in each of the above sections, the electromagnetic pump at the time of idling start compared with the conventional electromagnetic pump of this type. It is excellent in the stability of the discharge amount and the stability of the discharge amount under the change of the suction head, and has a characteristic that the power efficiency is high, so that the driving power required to obtain a constant discharge amount can be reduced. The cost can be reduced by reducing the power capacity and the size of the electromagnetic coil of the pump and the drive power supply unit. By eliminating the orifice of the discharge flow path that was conventionally installed, the high-precision machining method of the orifice becomes unnecessary,
Eliminating an increase in the ejection amount error caused by the orifice and omitting or simplifying the ejection amount adjustment step depending on the accuracy of the target ejection amount can greatly reduce the conventional cost in any case. Further, the effect of absorbing and mitigating the vibration noise caused by the reciprocating motion of the plunger by the buffering action of the air in the air chamber greatly contributes to lowering the vibration and noise of the entire pump using apparatus.

Since the means of the present invention is simple in structure and has a clear operation state, the present invention has a feature that the specific configuration and effect when applied to the same type pump of various structures can be easily considered in advance. Therefore, in this type of electromagnetic pump having a detailed configuration different from that of the embodiment described in this specification, it is possible to realize a predetermined operation and effect by applying the means described in this specification.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a first embodiment.

FIG. 2 is a diagram illustrating the distribution of air and liquid according to the first embodiment.

FIG. 3 is a characteristic diagram of a discharge amount / a suction head according to the first embodiment.

FIG. 4 is a longitudinal sectional view of a second embodiment.

FIG. 5 is a characteristic diagram of a discharge amount / a suction head according to a second embodiment.

FIG. 6 is a longitudinal sectional view of a third embodiment.

FIG. 7 is a longitudinal sectional view of a fourth embodiment.

FIG. 8 is a longitudinal sectional view of a fifth embodiment.

FIG. 9 is a longitudinal sectional view of a sixth embodiment.

FIG. 10 is a longitudinal sectional view of a seventh embodiment.

FIG. 11 is a longitudinal sectional view of Conventional Example 1.

FIG. 12 is a longitudinal sectional view of Conventional Example 2.

FIG. 13 is an explanatory diagram of a function of reducing a discharge amount error due to bubbles of an air chamber installation pump.

FIG. 14 shows the result of pressure oscillation observation of the liquid in the suction channel.

FIG. 15

FIG. 16

FIG. 17

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Electromagnetic coil 6 ... Cylindrical body 7 ... Discharge port 10 ... Suction port 12 ... Check valve 15 ... Plunger 17 ... Check valve 21 ... Support spring 22 ... Supporting spring 24 ... O-ring 25 ... O-ring holder 26 ... Pump chamber 27 ... Suction flow path 28 ... Discharge flow path 29 ... Liquid flow path 30 ... Air chamber 31 Communication part 33 Orifice 36 Plunger 46 Pump chamber 51 Support spring 52 Plunger 53 Closing valve 54 Valve seat 55・ Cylindrical body 61 ・ ・ ・ Support spring 62 ・ ・ ・ Plunger 63 ・ ・ ・ Closure valve 64 ・ ・ ・ Valve seat 65 ・ ・ ・ Check valve 66 ・ ・ ・ Pump chamber 67 ・ ・ ・ Check valve 68 ・ ・・ Cylindrical body 71 ・ ・ ・ Support spring 72 ・ ・ ・ Plunger 7 ... Closing valve 74 ... Check valve 75 ... Cylinder body 76 ... Pump chamber 78 ... Check valve 81 ... Support spring 82 ... Plunger 83 ... Closing valve 85 ... check valve 86 ... cylindrical body 89 ... check valve 91 ... electromagnetic coil 96 ... cylindrical body 97 ... discharge port 100 ... suction port 102 ... check valve 105 plunger 107 check valve 111 support spring 112 support spring 116 pump chamber 117 suction passage 118 discharge passage 119 liquid passage 120 orifice

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3H069 AA01 BB02 CC04 DD05 DD15 DD31 EE04 EE07 EE47 3H071 AA01 BB01 CC15 CC17 CC21 DD03 DD14 DD32 DD89

Claims (7)

[Claims] 1. A cylindrical body constituting a liquid flow path from a suction port to a discharge port via a suction flow path, a pump chamber, and a discharge flow path, and a plunger provided in the cylindrical body so as to be able to reciprocate. An electromagnetic coil configured to integrally form at least two valves of the check valve provided at the inlet of the pump chamber and the check valve provided at the outlet of the pump chamber with the cylindrical body and the plunger, respectively, to move the plunger forward; An electromagnetic device comprising an urging means for returning the plunger to supply the liquid in the discharge flow path from the discharge port to the outside by the movement of the plunger in the discharge direction, and to suck the liquid from the suction port into the suction flow path. An electromagnetic pump comprising: a pump having an air chamber having a gravity direction communicating with the suction flow path and an airtight structure in the other direction. 2. The electromagnetic pump according to claim 1, wherein said urging means comprises a pair of coil springs press-fitted respectively on the discharge port side and the suction port side of the plunger. 3. An electromagnetic pump according to claim 1, wherein said air chamber is provided with an orifice between a communication position communicating with a suction flow passage and a suction port. 4. The urging means comprises a coil spring press-fitted on the discharge port side of the plunger, and an end of the plunger on the suction port side and a contact portion with which the end of the plunger abuts. 2. The electromagnetic pump according to claim 1, wherein a closing valve that closes the liquid flow path at a plunger stop position and opens the flow path at a plunger movement position is configured. 5. The device according to claim 1, wherein the urging means comprises a coil spring press-fitted on the suction port side of the plunger, and an end of the plunger on the discharge port side and a contact portion with which the end of the plunger abuts. 2. The electromagnetic pump according to claim 1, wherein a closing valve that closes the liquid flow path at a plunger stop position and opens the flow path at a plunger movement position is configured. 6. A check valve provided at the inlet of the pump chamber is formed integrally with the plunger, and a check valve provided at the outlet of the pump chamber is formed integrally with the cylindrical body. Item 7. The electromagnetic pump according to Item 1. 7. A check valve provided at the inlet of the pump chamber is formed integrally with the cylindrical body, and a check valve provided at the outlet of the pump chamber is formed integrally with the plunger. Item 7. The electromagnetic pump according to Item 1.