JPH0325695B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is an electromagnetic pump for a gun-type oil burner that discharges and sprays pressure-fed fuel oil from a nozzle to ignite and burn it, by reducing deflagration noise when the burner ignites. A gun-type oil burner that controls the relationship between the pressure and rise time when the pump's discharge pressure rises, and eliminates the residual pressure of the pressurized fuel oil when the burner stops burning, in order to achieve so-called soft ignition. This invention pertains to improvements to the ignition pressure control device for electromagnetic pumps.

Prior Art In order to reduce the deflagration noise caused by the fuel pump when igniting the burner in a gun-type oil burner, a method for slowly delaying the pressure rise time of the fuel pump to cause soft ignition at relatively low pressure, and a method for eliminating residual pressure when the pump is stopped is the one disclosed in Japanese Patent Application Laid-Open No. 16703/1983, which was previously proposed by the inventors of the present application, and
There is one shown in Japanese Utility Model Application Publication No. 58-82481.

The step-up delay device for an electromagnetic plunger pump disclosed in Japanese Patent Application Laid-Open No. 16703/1983 is based on the following method: ``From the suction side of the pump, the electromagnetic plunger is reciprocated by supplying pulse current to the coil to energize it to perform a pumping action. A cylinder connected in parallel to the path leading to the discharge side via the suction valve, the pressure chamber and the discharge valve, and a cylinder fitted in the cylinder so as to be able to slide back and forth and transmitted from the discharge side to the outside. A plunger that moves in the cylinder toward the suction side in response to discharge pressure, and the discharge side and suction side of the cylinder that are partitioned by the plunger are communicated with each other, and fluid pressure from the discharge side is controlled. a leakage path that communicates with the suction side and provides a pressure transmission characteristic that determines the moving speed of the plunger in the suction side direction and delays the discharge pressure rise time, and a bottom portion of the cylinder in the suction side direction and the plunger. a pressure regulating spring that is pressurized between the plunger and the suction side end surface and presses the plunger toward the discharge side; a valve mechanism formed to block the leakage path by engagement with the suction side inner wall surface of the valve mechanism;
When the pump is stopped, the plunger is pressed toward the discharge side by the pressure regulating spring to open the valve mechanism, and the residual pressure on the discharge side that has passed through the leakage path is released to the suction side. It is something that has been done.

In addition, the residual pressure evacuation device for an electromagnetic pump disclosed in the above-mentioned Japanese Utility Model Publication No. 58-82481 is based on an electromagnetic pump that reciprocates by an electromagnetic force generated by passing a pulse current through an electromagnetic coil and a repulsive force of a spring. It has a suction valve and a discharge valve that open and close with the operation of a discharge plunger interlocked with the plunger, and has a mechanism that closes the discharge side flow path when the electromagnetic coil is not energized,
A leakage path from an internal part of the pump between the blocking machine and the discharge valve to the suction side of the pump is communicated with a relief path for excess pressure fluid from a relief valve that presses a valve seat with a pressure regulating spring. "Residual pressure evacuation device for electromagnetic pump".

Said Japanese Unexamined Patent Publication No. 54-16703 (Japanese Patent Publication No. 61-32511)
The electromagnetic plunger pump disclosed in No.
It can be used for gun-type oil burners that enable combustion of 6GPH, or 22nd rate per hour. Therefore, even if the amount of leakage from the leakage path of the boost delay device and the gap between the cylinder and plunger is large, if the amount is small compared to the amount of discharge from the nozzle, the pump's discharge capacity is sufficient to cover it. The degree of influence of reducing ejection performance is relatively small. However, as the amount of leakage increases, the stroke length during reciprocating operation of the electromagnetic plunger and the discharge plunger interlocked with the electromagnetic plunger increases, resulting in an increase in vibration and noise.

In recent years, the overwhelming majority of electromagnetic pumps for gun-type oil burners used in general household or relatively small commercial instant water heaters, boilers, or space heaters are those with a calorific value of approximately 30,000 Kcal. It is in.

The capacity of the nozzle for fuel oil spray in this case is
The current situation is that a combustion rate of up to 1.25GPH, or 4.5% per hour, is required. The fuel oil in this case is mainly kerosene, and its steady discharge pressure is 7.
The standard is Kgf/ ^cm2 .

It goes without saying that small-capacity electromagnetic pumps must also be smaller in capacity, smaller in size, and lighter in price for reasons of aging.

The orifice diameter of the 1.25GPH nozzle is approximately
The diameter is 0.27 mm, and in addition to this, flow resistance of the fuel oil is added by 3 to 9 swirl grooves carved in the tip cone that abuts the back of the orifice in order to provide swirling properties when the fuel oil is discharged and sprayed. Despite this, the discharge rate is maintained at 4.5 per hour as mentioned above. Therefore, when trying to limit the amount of leakage from the leakage path of the boost delay device to a value equal to or less than this discharge amount, the cross-sectional area of the leakage path is determined by the relative ease of mass production and the leakage area, that is, its length. Considering the increase in flow resistance, the limit is to make the hole extremely short with a diameter of about 0.2 mm.

The amount of leakage from this leakage path with a diameter of 0.2 mm was substantially 4.4 per hour.

However, even if the amount of leakage from the gap between the cylinder and the plunger in the boost delay device is not allowed, the discharge capacity of the electromagnetic pump needs to be approximately twice the discharge amount at steady discharge pressure. ,
In order to add a boost delay device, the pump must have a correspondingly large capacity, which is wasteful. However, in this case, the boost delay device also includes a residual pressure elimination device.

When the diameter of the leakage path is 0.2 mm, its cross-sectional area is ^0.01πmm2 , and in order to make the gap area between the cylinder and plunger of the boost delay device equal to this, if the cylinder thread diameter is, for example, 180000 mm, the plunger The diameter of the cylinder is 179,989 mm, and if we ignore this and set the diameter of the plunger to 50,000 mm, the diameter of the cylinder will be 500,399 mm, and the fitting part of the cylinder and plunger will be Even considering the flow resistance of the leakage area over the entire circumference, in the case of a low viscosity liquid such as kerosene, the gap requires an accuracy higher than the highest level of dimensional tolerance of the commonly used hole or shaft-based loose fit. year,
Not only is this method virtually unsuitable for mass production and has no economic efficiency, but there is a strong possibility that the plunger will not operate smoothly.

As is clear from the above explanation, this pump is particularly economically unsuitable as an electromagnetic pump for the small-sized, small-capacity gun-type oil burner.

What is disclosed in the above-mentioned Japanese Utility Model Publication No. 58-82481 is a residual pressure discharging device for an electromagnetic pump for the small-sized and small-capacity, especially gun-type oil burner, and the embodiment thereof is shown in FIGS. 8 to 9. The cross-sectional area of the fluid relief passage was substantially 0.011 mm ² and it was confirmed that approximately 1.2 of the fuel oil was discharged per hour. Generally, in this type of electromagnetic pump, a separate strainer is connected to the suction side to allow impurities such as dust, fibrous dirt, and sludge in the fuel oil to pass through, and furthermore, the strainer generated when the strainer is connected A filter with a capacity of 100 to 200 mesh is built in on the suction side of the pump body to prevent metal chips and other impurities from entering the pump body. The 100 mesh filter has a mesh size of 0.163 mm square, and the 200 mesh filter has a standard opening area of 0.081 mm square. In addition, porous synthetic resins such as paper and vinyl acetate are also used as filter materials, but if a filter with too fine mesh is used to prevent the passage of impurities in the fuel oil, is easily vaporized by the negative pressure when the pump suctions, which causes a so-called bubble blockage phenomenon, causing the pump to run dry, cutting off fuel oil supply and interrupting combustion. This can cause problems such as abnormal combustion, noise, and the generation of soot and non-flammable gas. Therefore, in order to prevent the air bubbles from clogging, the mesh of the filter must be made relatively large as described above.
Therefore, there is a drawback that the impurities in the fuel oil that has passed through this filter gradually accumulate in the escape passage and block it, thereby losing the effect of eliminating residual pressure. Therefore, the diameter of the leak hole of the boost delay device should be set to 0.2, for example.
mm, there is a serious defect in which the boost delay device loses its function due to the same reason as the leak hole is closed.

Furthermore, an electromagnetic pump having a pressure rise time adjusting device is disclosed in Japanese Patent Application Laid-open No. 7787/1987. This is an electromagnetic pump in which the volume of the pump chamber is changed by reciprocating the piston, and this volume change is used in cooperation with the suction valve to perform the pumping action. and guide the discharge pressure after the discharge valve to a high pressure side chamber partitioned by the plunger,
A low-pressure side chamber is connected upstream of the suction valve, the plunger is pressed by a main spring disposed in the low-pressure side chamber to bias it toward the high-pressure side chamber, and a communicating hole is formed in the axial direction. , the communication hole is provided with an orifice,
The high pressure side of the communication hole is closed by a valve biased by a spring, and a spring receiver and stopper is provided on the cylinder on the side that opposes the main spring of the plunger, and on the side facing the plunger. An adjustment rod having a valve at its tip that opens and closes the low pressure side of the communication hole is provided on the spring receiver and stopper, so that even when the plunger moves to the maximum against the main spring, fluid is removed from the low pressure side of the communication hole. It is characterized by a small amount of leakage occurring at all times.

This is simply a matter of incorporating the prior art described in the aforementioned Japanese Utility Model Application Publication No. 58-82481 into the one described in the aforementioned Japanese Unexamined Patent Publication No. 54-16703.

Further, in the detailed description of the invention, it is written from page 13, line 15 to page 14, line 2: ``By this movement of the plunger 22, the high pressure side 29a' of the communication hole 29 is opened away from the valve 34. This communication hole 29 is the valve 34
The position where the blockage is released (referred to as P ₁ point),
In other words, the following distance of the valve 34 to the communication hole 29 can be arbitrarily changed by adjusting the adjusting screw 35 and changing the setting force of the spring 33. ", but the high pressure side 29 of the communication hole 29
It is necessary to convert the protrusion height of a', and the spring 33 has much less repulsive force than the main spring 28, so the effect of the so-called composite spring affected by the difference in repulsive force is not recognized at all. ,
Even if the setting force of the spring 33 is changed, the valve 34
The following distance to the communication hole 29 remains unchanged. Therefore, in this explanation, it cannot be said that the following distance can be changed arbitrarily.

However, in this prior art, although a filter is interposed between the plunger body and the orifice body, contaminants including the metal chips in the fuel oil connect the extremely small diameter orifice of the communication hole. There is no escape from this serious defect, which is extremely likely to result in a build-up and blockage of the pressure rise time control device, causing it to lose its function.

Problems to be Solved by the Invention The present invention eliminates the above-mentioned drawbacks of the prior art, and improves the fuel oil discharge pressure at the time of ignition that adapts to soft ignition, the time to reach this point, and the discharge pressure for transition to normal combustion after ignition. This is due to the accumulation of impurities in the fuel oil, due to the combustion interruption when the combustion is frequently turned on and off, and the mechanism that quickly discharges the residual stress inside the pump to prepare for the next soft ignition when the pump is stopped. It prevents blockage of communication passages including orifices and air bubbles from clogging of the pump due to clogging of filters, and limits the increase in pump discharge capacity required for the soft ignition effect, resulting in a compact design with less loss. The object of the present invention is to provide an ignition pressure control device for an electromagnetic pump for a gun-type oil burner that is lightweight and can achieve economical reduction in cost and power consumption.

Means for Solving the Problems In order to solve the problems of the prior art described above, the ignition pressure control device for an electromagnetic pump for a gun-type oil burner according to the present invention provides a reciprocating motion by applying a pulse current to the coil. In parallel to the pump path from the suction port of a liquid displacement pump having a discharge plunger to the discharge port via the suction valve, the pressure chamber and the discharge valve, the pressure between the discharge valve and the discharge port is A first cylinder that communicates between the side and the suction side between the suction port and the suction valve, and a ring-shaped elastic packing that reciprocates within the first cylinder and prevents liquid leakage from the gap between the first cylinder and the first cylinder. In a device equipped with a first plunger that is loosely fitted, a second cylinder that extends through the first plunger in the axial direction is capable of allowing eccentricity, is capable of sliding back and forth, and is free from the gap between the first plunger and the second cylinder. A second plunger loosely fitted through annular elastic packing to prevent liquid leakage is arranged and fixed on the pressure side, and a bottomed through hole is provided in the axial direction of the second plunger that opens only to the suction side. An orifice is bored through the second plunger and communicates with the through hole from a main part of the outer periphery of the second plunger, and the annular packing passes through the gap between the second cylinder and the second plunger and connects to the orifice. The first cylinder further includes a valve that also serves as an opening/closing valve for a communication passage from the pressure side to the suction side partitioned by the first plunger through the passage hole; a pressure regulating spring that is interposed under pressure between a suction side bottom portion provided with a stopper and a suction side end portion of the first plunger and presses the first plunger in the discharge side direction; A flow rate suppression valve mechanism is provided that engages with the end of the first plunger in the suction side direction at the end of the movement in the lateral direction to suppress the flow rate from the communication path and limit it to a minute flow rate, and discharge the fluid pressure to the suction side, adjust the speed of movement of the first plunger toward the suction side, and provide a pressure transmission characteristic that delays the discharge pressure rise time to facilitate soft ignition of the burner; The present invention is characterized in that when combustion is stopped, the residual pressure of the fluid in the stopped pump is quickly discharged to the suction side by opening the flow control valve mechanism to prepare for the next burner soft ignition.

Effect The ignition pressure control device for an electromagnetic pump for a gun-type oil burner according to the present invention speeds up the rise time until reaching the discharge stress of the pump suitable for soft ignition of the burner, thereby increasing the pressure from the nozzle. In addition to preventing the so-called pre-dumping of non-combustible oil, the rise in the pressure suitable for soft ignition is also slowed down to slow ignition combustion, and after ignition, the discharge pressure is quickly raised to normal combustion, and the burner combustion is stopped at the same time. Residual pressure inside the stopped pump is quickly discharged to its suction side, ensuring soft ignition combustion even when the burner is repeatedly turned on and off, producing an explosion sound when ignited. prevent.

Accordingly, the first cylinder, the first plunger, and the second plunger are loosely fitted to each other so as to allow eccentricity of the second plunger with respect to the second cylinder,
A ring-shaped elastic packing is interposed to prevent liquid leakage from the gap between the two pairs of cylinders and the plunger that fit together, and the gap between the second cylinder 32 and the second plunger 33 is the same as that of the first cylinder. plunger 3
Due to the reciprocation of the first and second cylinders 32, the annular elastic packing forms a fluid communication path that functions as an on-off valve.

The gap is smaller than the length of one side of the opening of the filter, and since it slides back and forth, it has a self-cleaning effect and further prevents the intrusion of foreign substances in the fuel oil. This prevents clogging and prevents failure of this device.

These effects will be made more clear in the following description of the embodiments of the present invention.

Embodiments The present invention will be described below with reference to illustrative embodiments. 1 and 2, the magnetic head 8 and An electromagnetic plunger 2 that reciprocates within a guide case 4 provided between the annular magnetic pole 9 and a discharge plunger 3 that slides and reciprocates within a discharge ring 5 interlocks with the electromagnetic plunger 2, which is connected to the magnetic head 8 and the pump. Main body 1
It is supported by an auxiliary spring 6 and a return spring 7 between the main part of the main body. The change in volume of the pressure chamber 17 due to the reciprocating movement of the discharge plunger 3 and the resulting cooperative action with the suction valve 26 and discharge valve 27 perform a pumping action. That is, the fluid sucked from the suction port 14 of the suction joint 13 as shown by the arrow a flows through the filter 23, the suction valve 26, the pressure chamber 17, and the discharge valve 2.
7, passes vertically through the passage 18, the inside of the guide case 4, the inside of the electromagnetic plunger 2, and the inside of the magnetic head 8, passes through the solenoid valve 10, which is opened by energizing the solenoid valve coil 12 at the same time as pump operation, and then passes through the discharge joint 15. The liquid reaches the discharge port 16 and is discharged as shown by arrow b.

Although not shown, when a nozzle is connected to this discharge joint 15 by piping and is used for pressure-feeding fuel spray combustion in a gun-type oil burner, the discharge pressure during steady combustion, for example, 7 kgf/cm ² is adjusted by the discharge valve 27. This is done by a relief valve mechanism 20 that includes a valve seat 22 and a relief valve body 21 that are communicated through a passage 24 from the pressure-side main part inside the pump, and excess pressure fluid is returned to the suction side of the pump through a passage 25. Note 1
9 is an accumulator. Detailed explanations of the structure and operation of the above-mentioned devices are disclosed in Utility Model Publication No. 57-43102 "Electromagnetic Pump" and Utility Model Publication No. 53-3474 "Accumulator" which were previously proposed by the applicant. Therefore, the explanation thereof will be omitted below.

Next, a passage 2 is provided integrally with the main body 1 and connects the pressure side beyond the discharge valve 27 of the pump and its one end.
The pressure side and the suction side, which communicates between the suction valve 26 and the suction port 14 through the passage 29, are divided into the first cylinder 30, which is connected to the first cylinder 30 through the passage 29, and reciprocates, and the liquid from the gap therebetween is separated. The first plunger 31 is loosely fitted through an annular elastic packing (for example, O-ring hereinafter referred to as O-ring) 34 to prevent leakage. A bottomed second cylinder 32 that is open on the pressure side and has a through hole 52 on the suction side is installed in the axial direction of the first plunger 31, and the second cylinder 32 is eccentrically arranged with respect to the second cylinder 32. The second plunger 33 is loosely fitted to the first plunger 33 through O-rings 40, 40' which allow the second plunger 33 to freely slide and reciprocate and prevent liquid leakage from the gap therebetween.
An adjustment screw 49 is attached to the end of the cylinder 30 in the discharge side direction.
The O-ring 51 is used to maintain airtightness. The second plunger 3
A bottomed through hole 43 that opens only at the suction side port is bored in the axial direction of the cylinder 3, and an orifice 42 that communicates with the through hole 43 is drilled from a main part of the outer periphery of the hole 43. An arcuate groove 41 is provided in a main part of the outer periphery of the second plunger 33.

Incidentally, the first plunger 31 and the second cylinder 32
Since eccentricity on the axis between the cylinder and the second plunger 33 during manufacturing is geometrically unavoidable, a certain degree of dimensional tolerance is required, and the diameters of each cylinder and plunger are also different. Requires dimensional tolerances. In addition, each cylinder and plunger are likely to have an ellipse or a distorted circle due to machining, which may make it impossible to assemble the plunger, let alone smoothly reciprocate it. In order to prevent problems caused by these manufacturing errors, especially the eccentricity, in the embodiment of the present invention, the first
The cylinder 30 and the first plunger 31 are based on the axis h
9 and the fitting hole B10, and the second cylinder 32 and the second plunger 33 are made extremely easy to manufacture as the shaft reference h8 and the fitting holes D8 to D9 are commonly used loose fit. When the diameters of the first plunger 31 and the second plunger 33 are, for example, 18 mm and 5 mm, respectively, the O-rings 34, 40, 40' are inserted into the second plunger 33 within the tolerance of their respective crushing allowances. 1,
Eccentricity with respect to the second cylinders 30 and 32 was allowed, smooth sliding back and forth, and liquid leakage from the gap could be prevented.

If the clearance between the second cylinder 32 and the second plunger 33 is 50μm, this means that the maximum clearance of the hole D8 or D9 fitted with the commonly used shaft reference h8 is 66μm or 78μm, and the minimum clearance is 30μm.
The total cross-sectional area of this gap is approximately the same as the diameter of the orifice 42, as is clear from the above explanation.
In the case of a low-viscosity liquid such as kerosene, even when considering the flow resistance due to the leakage area that is much larger than the cross-sectional area of 0.2 mm and spans the entire circumference of the fitting part between the second plunger 33 and the second cylinder 32. It is much easier for liquid to pass through than through the orifice 42, and it can be used as a communication path for fuel oil.

The arcuate groove 41 allows fuel oil to flow through the arcuate groove 41 when there is a risk that the second plunger 33 hits the wall surface of the second cylinder 32 partially due to its eccentricity and blocks the orifice 42. This is provided to circulate the flow to the orifice 42.

The adjusting screw 49 is rotated to adjust the fitting length between the second plunger 33 and the second cylinder 32, and adjust the discharge pressure of the pump at the time of burner ignition. Rocknut 50
Fix it with the

The first plunger 31 provided with the second cylinder 32 may be coated with fluororesin or the like to prevent moisture in the fuel oil, oxidized oil, etc., in order to smooth the operation and prevent wear during its reciprocating operation. There is no risk of corrosion due to In particular, metals coated with an anti-friction agent or treated to harden the surface and provide lubricity should be avoided as there is a risk of clogging of the orifice 42 and communication passage due to flaking of these surface treatment substances. Good.

The first plunger facing the top 47 of the first plunger 31
A filter 46 is disposed at the bottom of the cylinder 30 on the pressure side. The filter 46 is finer than the filter 23 and is a separate strainer (not shown) connected to the suction joint 13 of the pump and re-passes the fuel oil passed through the filter 23. In this embodiment, the filter 46 is made of a wire mesh of 300 mesh. The number of eyes is approximately
22000, the length of one side of the opening of the Ichimoku square is
The standard is 0.044mm.

As mentioned earlier, the maximum clearance between the second plunger 33 and the second cylinder 32 in this embodiment is 0.066 to 0.078 mm,
and the first cylinder 30 have the maximum clearance with a loose fit between the commonly used shaft reference h9 and the fitting hole B10.
263μm, and the minimum clearance is 150μm, so the second
The eccentricity of the plunger 33 with respect to the second cylinder 32 and the first cylinder 30 is such that the first cylinder 3
0 and the first plunger 31, the ratio is adjusted more, and when the distance between the second cylinder 32 and the second plunger 33 is smaller, the ratio of adjustment becomes smaller. Therefore, when the second plunger 33 and the second cylinder 32 are inscribed at one point, the maximum gap is 0.081 mm, which is one side of a square that is the standard opening area of a 200-mesh wire mesh filter.
Of course, the second plunger 33 is not continuously pressed against one side of the second cylinder 32 because of the above-mentioned reason, so the clearance is also smaller than the opening area of the first eye of the 300-mesh wire mesh filter 46. It can be concluded that it is substantially smaller than 0.044 mm, which is one side of a square. However, the fact that the second cylinder 32 and the second plunger 33 have a fitting length makes it even more difficult for minute impurities in the fuel oil to pass through the gap. Moreover, the sliding reciprocation of the second cylinder 32 and the second plunger 33, together with the sliding movement of the O-rings 40, 40', has a self-cleaning effect that automatically cleans the gaps, so that even if the minute contaminants are It is equipped with the feature of removing objects even if they intervene.

Next, a bottom cover 35 having a stopper 36 screwed onto the suction side end of the first cylinder 30 is press-fitted between the first plunger 31 and the first plunger 31 is placed on the discharge side. A pressure regulating spring 37 is provided to press in the direction. At the end of the movement of the first plunger 31 in the suction side direction, that is, when the first plunger 31 abuts the stopper 36, the first plunger 31 engages with the end surface of the first plunger 31, and the through hole 52
The bottom cover 35 is provided with a suppression valve 45 held by an elastic body such as an elastic spring, which suppresses the flow rate of fuel oil from the bottom cover 35. The end face of the first plunger 31 that engages with the suppression valve 45 has a leakage path similar to the leakage path in the residual pressure evacuation device for an electromagnetic pump disclosed in the above-mentioned Japanese Utility Model Publication No. 58-82481, which communicates with the through hole 52. In addition, a leak path 44 is carved in order to limit the flow rate to a minute amount.
This leakage path 44 may be provided on the engagement surface of the suppression valve 45 instead of being provided on the end surface of the first plunger 31.

Stopper 36 that comes into contact with the first plunger 31
In order to prevent the passage of fuel oil from being blocked by the contact, it is necessary to take care to ensure a flow path, such as by providing a passage groove on the contact surface.

The bottom cover 35 is rotated to change the moving distance of the first plunger 31 to the stopper 36, thereby adjusting the pump discharge pressure rising time for transition to steady combustion after burner ignition.

The lock nut 39 is for fixing the bottom cover 35.

In addition, an airtight O-ring 3 is installed to prevent screw chips from entering the first cylinder 30 when the bottom cover 35 is rotated.
8 is desirably arranged inside the screw.

Furthermore, if it is not necessary to vary the travel distance of the first plunger 31 to adjust the pump discharge pressure rise time until the transition to steady combustion after burner ignition is performed, the bottom cover 35 may not be screwed in, but may be fixed with a pin or other means. It can be fitted using any suitable method.

Similarly, if variable adjustment of the discharge pressure of the pump at the time of ignition of the burner is not required, the adjustment screw 49 of the second plunger 33 can also be omitted, and it is sufficient to simply hold it fixed at the bottom of the discharge side of the first cylinder 30. .

In addition, the enlarged view of the main parts in FIG. 2 shows the suction joint 13, suction valve 26, discharge valve 27,
9. Although the relief valve mechanism 20 and the ignition discharge pressure control device of the present invention are depicted as if their axes are on the same plane, this is not necessarily necessary. However, the passage 2 that communicates each of the above parts
4, 25, 28, 29, etc. are short-circuited and straight as much as possible, so that the volume of the passage is reduced, and dissolved air and vaporized gas in the fuel oil accumulates and is released intermittently. This is necessary to prevent the discharge pressure from fluctuating due to air bubble blockage in the pump and fluctuations in the action of the accumulator. In order to allow the bubbles to pass through without any accumulation, the passage 2
It is desirable that passages 4 and 28 are provided upwardly toward the discharge side, and passages 25 and 29 are provided upwardly toward the suction side.

Next, with reference to Figure 3, the second
The operation of the embodiment of the ignition pressure control device for an electromagnetic pump for a gun-type burner according to the present invention having the configuration shown in the drawings will be described.

The pumping action is performed as described above by applying a pulse current to the coil 11 of the electromagnetic pump, and the fuel oil flowing from the discharge valve 27 to the discharge side reaches the first cylinder 30 from the passage 28 and passes through the filter 46. Then, the top 47 of the first plunger 31 is pressed.
The first plunger then begins to move toward the suction side against the repulsive force of the pressure regulating spring 37. and the second
By separating the end surface 48 of the cylinder 32 and the O-ring 40, a passage between the second cylinder 32 and the second plunger 33 is opened.

FIG. 3 is a diagram with time tsec. plotted on the horizontal axis and pump pressure PKgf/cm ² on the vertical axis, where the solid line shows the boosting characteristics of the electromagnetic pump not equipped with the ignition pressure control device of the present invention. In the diagram, the one-dot chain line and the dotted line indicate the boost characteristics in the control device of the present invention.

The time when the passage in the gap opens is when the discharge pressure of the pump capable of igniting the burner is reached, and P ₁
It is shown with. The time from when the pump starts until the pressure reaches _P1 is the time it takes for the fuel oil to fill the volume obtained by multiplying the cross-sectional area of the first plunger 31 and the second plunger 33 by the travel distance, and the pressure It has a sharp rise, and is not much different from that shown by the solid line, so that the adverse effect of so-called pre-sag from the nozzle before ignition can be avoided.

When the passage in the gap is opened, the fuel oil is discharged from the orifice 42 through the through holes 43 and 52 and from the passage 29 toward the pump suction port 14, while the flow rate is restricted by the orifice 42 and the fuel oil is discharged from the first plunger 31. The first plunger 31 is moved until it comes into contact with the stopper 36 by adjusting the moving speed of the first plunger 31 toward the suction side to provide a pressure transmission characteristic that delays the discharge pressure rise time. The pressure at this point is designated P ₂ .

At the same time as the first plunger 31 contacts the stopper 36, its end surface engages the suppression valve 45, so that the passage 29 is restricted from the orifice 42.
The flow rate of the fuel oil discharged toward is further suppressed to a very small amount, and only the amount leaks from the leak path 44, and the discharge pressure of the pump increases rapidly from the point _P2 , and is reduced by the relief valve mechanism 20. The discharge pressure reaches the adjusted normal combustion discharge pressure _P3 , and that pressure is maintained thereafter.

Ignition of the burner is carried out immediately after the pump discharge pressure rises to _P1 , and combustion is already sufficient at least at _P2 . The increase in discharge pressure from P ₁ to P ₂ is relatively slow.

The amount of combustion in a gun-type oil burner, that is, the flow rate of spray discharge from the nozzle, is proportional to the square root of the discharge pressure, so the pump discharge pressure during steady combustion is P ₃
For example, if it is 7Kgf/cm ² and the discharge pressure P ₁ at the time of ignition is 1.7Kgf/cm ² , then In other words, since the amount of fuel oil during ignition can be halved compared to during steady combustion, the explosion noise during ignition can be reduced and so-called soft ignition can be achieved.

If it is necessary to increase or decrease the combustion oil discharge pressure at the time of ignition depending on the characteristics of the burner, as mentioned earlier, turn the adjustment screw 49 to set the O - ring 40 and second
By adjusting the distance from the end surface 48 of the cylinder 32,
This is the adjustment of the timing of opening the gap between the second plunger 33 and the second cylinder 32, that is, _P1 .

Also, by rotating the bottom cover 35, the stopper 36 and the first
_P2 can be adjusted by adjusting the distance to the plunger 31, that is, the moving distance of the first plunger 31.

Point P ₁ ' in the diagram indicated by a dotted line is the O-ring 4.
0 and the end face 48 to increase the discharge pressure of the pump at the time of ignition, and point P2 _' indicates the case where the distance between the stopper 36 and the first plunger 31 is reduced to increase the discharge pressure of the pump after ignition. This is an example of a case where the pressure increase time to the steady discharge pressure is shortened.

When the burner stops combustion, the pump also stops at the same time, the first plunger 31 returns to its original resting position, and the residual pressure on the discharge side is reduced so that the fuel oil in the first and second cylinders 30, 32 flows into the passage 29. Even if it is used in cases where burner combustion is frequently turned on and off, such as in instant water heaters,
It is always prepared for the next soft ignition.

Note that when the first plunger 31 returns to the rest position, the end surface 48 of the second cylinder 32
O-ring 40 that also serves as an on-off valve for plunger 33
Confirm that the pressure at the time when the communication passage in the gap is closed by engagement with the burner is at the P ₁ and P ₁ ' points, and that the burner has entered the combustion state after ignition from before the ignition. Since the igniter continues to generate sparks until the ignition occurs, soft ignition is always possible as long as the pump discharge pressure drops to the P ₁ and P ₁ ' points. When it is necessary to eliminate the low residual pressure inside the pump discharge side after the communication passage in the gap is closed, the solenoid valve 10 is closed by adding a delay circuit for cutting off the current to the solenoid valve coil 12 of the pump. Give a time difference, during which time the discharge port 16
This can be processed by emitting it from a nozzle and burning it.

In addition, the second plunger 33 is connected to the second cylinder 3
The first plunger 31 and the first cylinder 30 including the second plunger 31 and the first cylinder 30 are allowed to be eccentric, and are easy to manufacture so that they can slide and reciprocate with each other, and the clearance between the second plunger 33 and the second cylinder 32 is reduced. As described above, it has the effect of blocking the passage of fine contaminants in the fuel oil and acts as a filter, and the self-cleaning action of the two by sliding back and forth.

Effects of the Invention As detailed above, the ignition pressure control device for an electromagnetic pump for a gun-type oil burner according to the present invention has the following features:
Particularly, since it has the configuration described in the embodiment, the following effects can be obtained.

(b) When the burner is ignited, the discharge pressure of the electromagnetic pump for the gun-type oil burner that operates at the same time is rapidly raised to a low pressure suitable for so-called soft ignition in order to reduce deflagration noise when the burner is ignited. This method prevents soot and bad odor due to so-called dripping of unfueled oil from the nozzle that occurs during that time, and makes the pressure rise relatively slow before and after soft ignition and until sufficient combustion occurs after ignition, and then reduces the discharge pressure. Since the combustion can be rapidly increased to steady combustion, the ignition noise of the burner is reduced.

(b) Since the discharge pressure of the pump suitable for soft ignition and the discharge pressure and time from ignition combustion to steady combustion can be adjusted, the discharge pressure rise characteristics of each fuel oil are suitable for the ignition combustion characteristics of the burner. can be adjusted to

(c) The residual pressure of the fuel oil inside the pump when the burner and pump are stopped has a mechanism that quickly removes it, so even if the burner combustion is repeatedly turned on and off, the residual pressure is always maintained. Prepared for soft ignition, reducing deflagration noise at ignition and avoiding
A predetermined pump pressure increase characteristic can be reliably obtained.

(d) In order to obtain pressure increase characteristics of the pump for soft ignition of the burner, a hole is provided in the second plunger 33 in order to adjust the moving speed of the first plunger 31 and the second plunger 33 and provide pressure transmission characteristics. and an orifice 42 that limits the amount of fuel oil leaking from the discharge side to the suction side, and in particular, a suppression valve provided on the suction side end of the first plunger 31 and the bottom cover 35 that engages therewith. 45
The flow rate control valve mechanism constituted by the above limits the amount of leakage to an extremely small amount, eliminates loss of discharge capacity of the pump, and brings about economy due to small capacity, small size, and weight reduction.

(e) The clearance between the second cylinder 32 and the second plunger 33, which is used as a part of the communication passage for leaking fuel oil from the discharge side to the suction side, is the same as that between the first cylinder 30 and the first plunger 31. In addition to the clearance, the commonly used shaft reference and the fitting hole are loosely fitted, which allows for eccentricity in manufacturing, allowing smooth sliding back and forth, and eliminating manufacturing difficulties. In addition to making it economical, the eccentricity can be adjusted within the allowable range of the crushing margin of this O-ring through a ring-shaped elastic packing such as a dynamic O-ring, which prevents liquid leakage from the gap between them. It covers.

(f) The second cylinder 32 and the second plunger 33
The maximum gap is less than the length of one side of the opening in the mesh of a 200-mesh wire mesh filter, and the actual gap is less than the length of one side of the opening in the mesh of a 300-mesh wire mesh filter. In addition to being considered small, the second cylinder 3
2 and the second plunger 33 have a fitting length, this makes it more difficult for impurities in the combustion oil to flow through this gap and prevents the inflow. It has a higher degree of overperformance than comparable filters. Furthermore, the sliding reciprocation between the second cylinder 32 and the second plunger 33
In conjunction with the sliding movement with the O-ring 40, which acts as an on-off valve that opens and closes the gap in the fuel oil leak communication passage provided in 3, there is a self-cleaning function that automatically cleans this gap. Even if fine contaminants in the fuel oil, such as dust, fibrous dirt, sludge, metal chips, etc., pass through the filters and enter the gaps, they are eliminated.

Therefore, there is no risk that the orifice 42 or the narrow portion of the leak communication path will be blocked by fine foreign matter in the fuel oil, impairing the discharge pressure increase characteristic and causing the entire device to malfunction. .

(G) As mentioned above, since the second plunger 33 and the second cylinder 32 can reject and eliminate fine impurities in the fuel oil, the filter on the suction side of the pump should be made of a fine filter that is easily clogged. Since there is no need to do so, it is possible to eliminate the cause of clogging of air bubbles in the pump due to the vaporization phenomenon of fuel oil that occurs due to the clogging of the filter due to the adhesion of the foreign matter, that is, a factor that causes pump discharge failure.

As described above, the ignition pressure control device for an electromagnetic pump for a gun-type oil burner according to the present invention has great industrial benefits.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view showing a partial cross section of an embodiment of the present invention, Fig. 2 is an enlarged sectional view of the main part along line A-A in Fig. 1, and Fig. 3 is an ignition diagram of the present invention and a conventional example. FIG. DESCRIPTION OF SYMBOLS 1... Main body, 2... Electromagnetic plunger, 3... Discharge plunger, 17... Pressure chamber, 26... Suction valve, 27... Discharge valve, 28... Passage, 29... Passage, 30... First Cylinder, 31...First plunger, 32...Second cylinder, 33...Second plunger, 34...O-ring, 35...Bottom cover, 3
6...Stopper, 37...Pressure adjustment spring, 40...O
-Ring, 41... arcuate groove, 42... orifice, 44... leakage path, 45... suppression valve.

Claims (1)

[Scope of Claims] 1. Regarding the pump path from the suction port of a liquid displacement pump having a discharge plunger that reciprocates by applying a pulse current to a coil, through a suction valve, a pressure chamber, and a discharge valve to a discharge port. , in parallel thereto, a first valve that communicates a pressure side between the discharge valve and the discharge port and a suction side between the suction port and the suction valve.
A cylinder and a first plunger that reciprocates within the first cylinder and is loosely fitted through an annular elastic packing that prevents fluid leakage from a gap between the first plunger and the first plunger. A second plunger is loosely fitted into the second cylinder extending in the direction through a ring-shaped elastic packing that can tolerate eccentricity and can freely slide back and forth, and prevents liquid leakage from the gap between the second plunger and the second plunger. A bottomed through hole is provided and fixed to the side, and opens only to the suction side in the axial direction of the second plunger, and an orifice is provided that communicates with the through hole from a main part of the outer periphery of the second plunger. The annular elastic packing passes through the gap between the second cylinder and the second plunger, passes from the orifice through the through hole, and defines the first cylinder by the first plunger. A pressurized interposition is provided between the suction side bottom portion of the first cylinder, which is provided with a stopper, and the suction side end portion of the first plunger, including one that also serves as an on-off valve for the communication passage from the pressure side to the suction side. a pressure regulating spring that presses the first plunger in the discharge side direction; and a pressure regulating spring that engages with an end of the first plunger in the suction side direction at the end of movement of the first plunger in the suction side direction. Providing a flow rate suppression valve mechanism that suppresses the flow rate from the communication path and limits it to a minute flow rate,
The fluid pressure from the discharge side is discharged to the suction side, and the moving speed of the first plunger toward the suction side is adjusted to provide a pressure transmission characteristic that delays the discharge pressure rise time, thereby softly igniting the burner. A solenoid for a gun-type oil burner, characterized in that when combustion is stopped, the residual pressure of fluid in the stopped pump is quickly discharged to the suction side by opening the flow rate suppression valve mechanism to prepare for the next soft ignition of the burner. Pump ignition pressure control device. 2. The clearance between the second cylinder and the second plunger is equal to or less than the length of one side of the mesh opening of a 200-mesh wire mesh filter, and the flow rate of fuel oil passing through the communication path formed by the clearance is as described above. The ignition pressure control device for an electromagnetic pump for a gun-type oil burner according to claim 1, wherein the pressure control device is set to be larger than the flow rate passing through the orifice. 3. An adjustment screw screwed into one end of the second plunger and the end of the first cylinder in the discharge side direction so that the discharge pressure at the time of ignition can be adjusted by adjusting the length of the fit between the second plunger and the second cylinder. An ignition pressure control device for an electromagnetic pump for a gun-type oil burner according to claim 1, characterized in that the device is provided with: 4. The gun type oil burner according to claim 1, characterized in that an arcuate groove is provided in the main outer peripheral part of the second plunger in which an orifice communicating with the through hole is drilled. Pressure control device for ignition of electromagnetic pumps. 5. A moving distance adjusting mechanism that adjusts the moving distance of the first plunger in the suction side direction by changing the position of a stopper provided at the bottom of the first cylinder in the suction side direction. A pressure control device at the time of ignition of an electromagnetic pump for a gun-type oil burner according to item 1. 6. The flow rate suppression valve mechanism is characterized in that a minute leakage path is formed between an end of the first plunger in the suction side direction and a suppression valve that is engaged therewith. The ignition pressure control device for an electromagnetic pump for a gun-type oil burner according to item 1.