JPH01150083A - Solenoid three way valve - Google Patents

Abstract

PURPOSE:To increase electromagnetic attracting force preventing the deformation of a stopper while the leakage of magnetic flux by forming the stopper of an inner valve with a non-magnetic material of hard quality, in the case of a solenoid three way valve having the inner valve and an outer valve. CONSTITUTION:An outer valve 39 and an inner valve 47 are housed in a valve body 30 having a fluid supply port X, fluid take out port Y and a fluid discharge port Z. An electromagnetic coil 51 and an iron core 61 are arranged facing to a flange part 41 in an upper part of the outer valve 39. The iron core 61 provides in its center part a stopper member 62, consisting of non- magnetic material of hard quality, adapted to an upper end surface of the inner valve 47. When a solenoid coil is not in conduction, the outer valve 39 is pressed down by a spring 52 connecting the port X to communicate with the port Y, and when the solenoid coil is electrified, the outer valve is lifted connecting the port Y to communicate with the port Z.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a three-way solenoid valve, and is particularly suitable for use in a fuel injection device for an internal combustion engine to control fuel injection timing and injection amount. between three-way solenoid valves.

"Background Art" For example, a diesel engine fuel injection device disclosed in Japanese Patent Application Laid-Open No. 59-165858 uses a three-way solenoid valve to control injection timing and injection amount. FIG. 4 shows a configuration diagram of this type of fuel injection device for a diesel engine. In FIG. 4, a pressure pump 29 and a pressure regulator 2 are shown.
The fuel pressurized to a constant high pressure by 6 passes through the conduit 27,
On the one hand, a fuel reservoir 2 is located above the seat of the nozzle needle 1 via a damping device (e.g. an accumulator) 28.
, which leads to the conduit 11 via a three-way solenoid valve 12 connected to an electronic control device t15, which receives on the other hand a signal from a bottom dead center detector 16 indicating the reference position, and which further connects to a plate valve 9.
It has arrived at the control room 8 where the return spring 7 is housed.

When the three-way solenoid valve 12 is in a rest state, that is, in a state in which it is not electrically excited, the fluid discharge port Z of the three-way solenoid valve 12 connected to the leak pipe 13 is closed. The fuel that has arrived at the fuel storage chamber 2 is forced into the nozzle needle 1 due to its pressure.
tries to push up the hydraulic piston 6, bottle 4. Control chamber 8 acting on the nozzle needle 1 via the flange 3
The pressure of the fuel and the force exerted by the spring 5 are superior to each other, and as a result, the nozzle needle 1 is seated on the lower seat in the figure, and no fuel is injected. This is to prevent the plate valve 9 from floating during the operation, and its force is so small that it can be ignored compared to the force of the spring 5 and the pressure exerted on the hydraulic piston 6.

When current flows through the coil of the three-way solenoid valve 12, injection is performed as follows. When the three-way solenoid valve 12 is energized, the fluid supply port X of the three-way solenoid valve 12 connected to the conduit 27 and the fluid outlet port 7 of the three-way solenoid valve 12 connected to the conduit 11 are cut off, and leakage occurs instead. The fluid discharge bows 52 connected to the conduit 13 communicate with each other. The pressure in the conduit 11 therefore falls, and the pressure in the control chamber 8 also falls relatively slowly due to the action of the orifice 10 provided in the plate valve 9. When the difference between the upward force due to the pressure in the fuel reservoir chamber 2 and the downward force due to the pressure in the control chamber 8 exceeds the force of the spring 5 even slightly, the nozzle needle 1 begins to open. When the nozzle needle 1 is raised by a small height, its momentum is accelerated by the pressure exerted on the surface of the seat.

When the preset injection period ends, the excitation of the three-way solenoid valve 12 is interrupted, and the fluid supply port X connected to the conduit 27 opens and the fluid discharge port Z connected to the leak conduit 13 opens.
is blocked. As a result, high pressure fuel flows into the control chamber 8 from the conduit 27 . At this time, the plate valve 9 has a weak return spring 7.
The road opens downward in the figure, and a suddenly larger road area is secured.

When the force of the spring 5 eventually exceeds the difference between the pressure in the fuel reservoir chamber 2 and the pressure in the control chamber 8, the nozzle needle 1
is pushed down and injection ends.

"Prior Art" A conventional three-way solenoid valve 12 used in the above-mentioned diesel engine fuel injection device has a 1'A construction as shown in FIG. In FIG. 5, 30 is a valve body, which has a fluid supply port 34, and a first horizontal road 36 that communicates the vertical passage 34 with the fluid discharge port 2.

A first valve seat 37 is provided at the upper end of the vertical passage 34;
A first fitting hole 38 is bored at a position facing the valve seat 37.

An outer valve 39 is slidably fitted into the first fitting hole 38 . At the lower end of this outer valve 39, a first
A poppet portion 40 is formed that approaches and separates from the valve seat 37, and an armature 41 is integrally fixed to the upper end. Further, inside the outer valve 39, a second vertical passage 42 whose one end opens into the first vertical passage 34, and a second horizontal passage 43 connected to the other end of this vertical passage 42 are formed. 43 is communicated with the fluid supply port X via a diagonal road 44 formed in the valve body 30. Judong g! I42 and side passage 4
A second valve seat 45 is provided in the long throw section of No. 3. Also,
A second fitting hole 46 is bored at a position facing the second valve seat 45.

An inner valve 47 is fitted into a second fitting hole 46 formed in the outer valve 39, and the outer valve 39 and the inner valve 47 are assembled so as to be slidable relative to each other.

A poppet portion 48 that approaches and separates from the second valve seat 45 is formed at the lower end of the inner valve 47, and a small diameter portion 57 with a reduced outer diameter is provided at the upper end to prevent leakage of magnetic flux to the inner valve 47. The small diameter portion 57 has a stopper portion 50 corresponding to a stopper member formed on a part of the iron core 49 made of a ferromagnetic material attached to the upper part of the bulb body 30.
, and is prevented from moving upward in the figure.

A first annular groove 58 is bored in the iron core 49 to form the stopper portion 49, and a second annular groove 59 is formed in which a solenoid coil 51 for magnetizing the iron core 49 is disposed. is drilled. The iron core 49, the solenoid coil 51, and the armature 41 constitute electromagnetic means for attracting the outer valve 39.

A spring 52 urges the outer valve 39 downward in the drawing and presses the poppet portion 40 against the first valve seat 37.

However, the solenoid coil 51 is repeatedly energized and cut off, and each time the outer valve 39 is attracted, the outer valve 3
9 and the inner valve 47 repeatedly collide with each other, a force acts on the stopper portion 50 as i# impact force via the inner valve 47, and the small diameter portion 57 of the inner valve 47 collides with the iron core 49.
The magnetic flux gradually sinks into the stopper part 50 of the iron core, and because magnetic flux leaks from the stopper part 50 integrally formed with the iron core to the inner valve 47, the electromagnetic attraction force that attracts the outer valve 39 decreases, and the action of attracting the outer valve 39 becomes slow. In addition, in order to quickly perform the suction and shift operation of the outer valve 39, the current flowing through the solenoid coil 5J is strengthened, but there is a problem in that the solenoid coil 51 and the like must be made larger.

[Problems to be Solved by the Invention] Therefore, the present invention was made to solve the above problems, and it prevents the inner valve from sinking into the stopper member, and prevents the magnetic flux from flowing from the stopper member to the inner valve. It is an object of the present invention to provide a three-way solenoid valve that prevents leakage, increases the electromagnetic attraction force that attracts an outer valve, and allows the outer valve to quickly respond to operation.

"Means for Solving the Problems" Therefore, the present invention has a fluid supply port, a fluid take-out port, and a fluid discharge port, and a first valve is provided in the middle of a passage connecting between the fluid take-out port and the fluid discharge port. has a seat,
and a valve body provided with a first fitting hole at a position facing the first valve seat, and a valve body slidably fitted into the first fitting hole so as to be able to come into contact with and separate from the first valve seat, A second valve seat is provided in the middle of the passage connecting the fluid supply port and the fluid extraction port, and a second fitting hole is provided at a position facing the second valve seat, and a flange is provided at the upper part. an outer valve formed with a flange-shaped portion; an inner valve slidably fitted into the second fitting hole so as to be able to come into and out of contact with the second valve seat; and a central core member facing the flange-shaped portion of the outer valve. ,
an electromagnetic coil disposed on the outer periphery of the central core member; an outer peripheral core member located on the outer periphery of the electromagnetic coil and substantially facing the flange-like portion; and an upper end surface of the inner valve at approximately the center of the central core member. Provided is a three-way solenoid valve characterized by comprising a stopper member made of a hard non-magnetic material and disposed so as to come into contact with the stopper member.

According to the Doi configuration, when the electromagnetic coil is energized in a state where the first valve is in contact with the outer valve and the fluid supply port and the fluid extraction port are in communication, the outer valve It is attracted to the electromagnetic coil side through the central core member and outer core member made of hard material, and slides until it collides with the inner valve, which is pressed against the stopper member by fluid pressure.At this time, the stopper member is made of a hard material. Therefore, the stopper member will not be plastically deformed due to the impact when the outer valve collides, and the inner valve will not sink into the stopper member.Also, since the stopper member is made of a non-magnetic material, there will be no damage caused by the electromagnetic coil. Magnetic flux is transmitted from the stopper member via the center core B material
'Leakage to the inner valve is prevented, and the magnetic flux generated in the electromagnetic coil draws a leap line between the outer core member, the flange-like part of the outer valve, and the center core member, so the electromagnetic attraction force that attracts the outer valve is reduced. As a result, the operational response of the outer valve is speeded up. Then, the second valve seat and the inner valve come into contact with each other, and the state is switched to a state where the fluid take-out port and the fluid discharge port are communicated with each other.

"Example" Next, an embodiment of the present invention will be described based on FIG.

In FIG. 1, the substantially cylindrical valve body 30 is
It has a fluid supply port X, a fluid take-out port Y, and a fluid discharge port Z.
A first vertical passage 34 that opens to the fluid discharge port Z, and a first horizontal passage 36 that communicates the vertical passage 34 with the fluid discharge port Z are formed. A first valve seat 37 is provided at the upper end of the vertical passage 34, and a first fitting hole 38 is bored at a position facing the first valve seat 37.

The vertical passage 34 and the horizontal passage 36 form a first passage that communicates the fluid take-out port and the fluid discharge port Z.

A cylindrical outer valve 39 is slidably fitted into the first fitting hole 38 of the valve body 30 . A poppet portion 40 that approaches and separates from the first valve seat 37 is formed at the lower end of the outer valve 39, and a generally disc-shaped armature 41 corresponding to a flange-shaped portion is integrally provided at the upper end.

Further, inside the outer valve 39, a second vertical passage 42 whose lower end opens to the first m-th passage 34, and a second horizontal passage 43 connected to the upper end of this vertical passage 42 are formed. 43 communicates with the fluid supply port X via an oblique passage 44 bored in the valve body 30. A second valve seat 45 is provided in a continuous portion between the vertical passage 42 and the horizontal passage 43. Also, a second fitting hole 4 is provided at a position facing the second valve seat 45.
6 is drilled.

Said second vertical passage 42. Second horizontal passage 43 and diagonal passage 44
forms a second passage that communicates between the first vertical passage 34 and the fluid supply port X.

A substantially cylindrical inner valve 47 is fitted into the second fitting hole 46 of the outer valve 39, and the outer valve 39 and the inner valve 47 are assembled to be slidable relative to each other. A poppet portion 48 is formed at the lower end of the inner valve 47 so as to come into contact with and separate from the second valve seats 45 of the three outer valves. Further, the upper end of the inner valve 47 is provided with an inner valve 47.
A small diameter portion 5 whose outer diameter is reduced to prevent leakage of magnetic flux to
7 is provided. Further, the length of the inner valve 47 is determined so that when the poppet portion 48 of the inner valve 47 comes into pressure contact with the second valve seat 45 of the outer valve 39, the small diameter portion 57 protrudes from the upper end of the outer valve 39 by a minute length 66. It is being

An iron core 61 is disposed in the upper part of the valve body 30 so as to face the armature 41 of the outer valve 39 with a spacer 56 in between. The core 61 consists of a center core member 61a located on the inside and a substantially cylindrical outer core member 61b that also serves as a housing.
A solenoid coil 5 is provided between the outer peripheral iron core member 61b and the
1 is wound around a bobbin 53. Further, in order to provide an inner valve stopper 62 corresponding to a stopper member, a tapered portion whose diameter continuously decreases upward is provided in the central portion of the central core member 61a located above the inner valve 47 at the lower end. A mounting hole 63 with a uniform diameter is drilled.

The inner valve stopper 62 is made of a hardened non-magnetic material (for example, hardened stainless steel).
, has a stepped cylindrical shape having a large diameter portion 64 and a small diameter portion 65. Then, the large diameter portion 64 side is attached to the center core member 61.
It is fitted and fixed in the arrangement hole 63 of a. The lower end surface of the small diameter portion 65 of the inner valve stopper 62 serves as an abutment surface corresponding to the small diameter portion 57 of the inner valve 47, and is prevented from moving upward in the figure. Furthermore, a spring 52 is engaged with the end surface of the large diameter portion 64 on the side continuous with the small diameter portion 64 for urging the outer valve 39 downward in the figure to press the poppet portion 40 into contact with the first valve seat 37. ing.

Note that 67 is a cord for supplying power to the solenoid coil 51, and is attached to the iron core 61 by a cord clamp 68.

[Operation J] Next, the operation of the above embodiment is explained in Figs. 1 and 2.
This will be explained based on the diagram.

In FIG. 2, the three-way solenoid valve 60 is in a de-energized state, and the outer valve 39 is filled with P C by the high-pressure fuel in the first vertical passage 34.
Pc×π(ct
A downward hydraulic pressure corresponding to 22-ct,'')/4 is applied, and the downward resultant force is set to be greater than the upward hydraulic pressure, so that the poppet portion 40 of the outer valve 39 touches the first valve seat 37. The 11th!1st passage 3
4 and the first horizontal passage 36 are cut off. Here,
Pc is the pressure of high pressure fuel, d is the diameter of the second valve seat 45, d
2 is the outer diameter of the inner valve 47, and d is the diameter of the first vertical passage.

On the other hand, the poppet portion 48 of the inner valve 47 has a horizontal passage 4
3 hydraulic pressure (PcXπd2')/4 acts upward,
Since the inner valve 47 is in contact with the inner valve stopper 62, the poppet portion 48 is removed from the second valve seat 45, and the horizontal passage 43 and the second vertical passage 42 are communicated with each other. Therefore, the fluid take-out port Y and the fluid discharge port Z are cut off, the fluid supply port X and the fluid take-out port Y are communicated with each other, and high-pressure fuel is supplied from the fluid supply port X to the fluid take-out port Y. ing.

In this state, when a current is applied to the solenoid coil 51 and the three-way solenoid valve 60 is energized, a magnetic field generated by the solenoid coil 51 is generated between the center core member 61a, the outer core member 61b, and the armature 41 as shown in FIG. The armature 41 of the outer valve 39 is drawn into the iron core 61 as shown in FIG. slide upward until it reaches the desired position. A biasing force F of a spring 52 is applied to the three outer valves.
r and P c X due to the high pressure fuel present in the horizontal passage 43
Although the hydraulic pressure of yt (d 2' d +")/4 is acting downward, the upward electromagnetic attraction force Fup by the solenoid coil 51 is set to be sufficiently larger than the downward resultant force. It quickly slides upward and is sucked to a position where a gap corresponding to a minute length 66 is left between it and the end face of the iron core 61. At this time, the outer valve 3
9 is pressed against the poppet portion 48 of the inner valve 47, and an impact force is applied to the inner valve stopper 62 through the inner valve 47. However, since the inner valve stopper 62 is made of a hardened material, the inner valve 47 The small diameter portion 57 is the inner valve stopper 62
The small diameter portion 65 will not sink into the small diameter portion 65, and the small diameter portion 65 will not be deformed into a barrel shape due to impact force. Furthermore, since the inner valve stopper 62 is made of a non-magnetic material, the magnetic flux draws a closed curve between the iron core 61 and the armature 41, and the magnetic flux leaks from the central iron core member 61a to the inner valve 47 via the inner valve stopper 62. Therefore, the electromagnetic attraction force Fup that attracts the outer valve 39 does not decrease. Then, the outer valve 39 and the iron core 6
1, so that the outer valve 39 will not enter the iron core 61, and the inner valve 47 will not enter the iron core 61.
Pressure contact between the poppet portion 48 and the second valve seat is also ensured.

In this state, the second valve seat 45 of the outer valve 39 comes into pressure contact with the poppet portion 48 of the inner valve 47, cutting off the horizontal passage 43 and the vertical passage 42, and the poppet portion 40 of the outer valve 39 separates from the first valve seat 37. The vertical passage 34 and the horizontal passage 36 are communicated with each other. Therefore, the fluid supply port X and the fluid extraction port Y are cut off, and the fluid extraction port
and the fluid discharge port Z, and high-pressure fuel is discharged from the fluid take-out port Y to the fluid discharge port Z.

In FIG. 3, the horizontal axis shows the current I ( This is a characteristic diagram showing the characteristics when the electromagnetic attraction force F up (K gf) is taken on the fir shaft.The larger the electromagnetic attraction force Fup is for a certain current, the more In this figure, the embodiment of the present invention in which the inner valve stopper 62 is made of a non-magnetic material is preferable because the actuation response is quick and the three-way valve 60 can be downsized, compared to the conventional example. It can be seen that the electromagnetic attractive force Fup increases by about 30 to 50%.

"Other Embodiments" Further, other embodiments shown in FIG. 6 differ from the above embodiments in stopper members, and the inner valve stopper 71 made of a hard non-magnetic material such as bearing steel is different from the center core member 61a.
The stopper receiver 70 is press-fitted into the lower part of the stopper receiver 70, which has a large diameter part and a small diameter part. The inner valve stopper 7 is in contact with the inner valve 47 and has a VI structure that prevents magnetic flux from leaking to the inner valve 47 via the stopper receiver 70.

In addition, in each of the embodiments described in section 2, the central core member 61a and the outer peripheral core member 61b are separate bodies, but they may be integrally formed.

Further, the present invention is not limited to the details of the structure illustrated in each of the embodiments. For example, the three-way solenoid valve 60 has an inner valve 47 and an outer valve 39.
The armature 4 has an outer valve 39 in the form of a flange.
1, it may be of the type that is sucked by the central core member 61a and the outer peripheral core member 61b, and the diagonal passage 44 connecting the fluid supply port X and the second lateral passage 43 is on the extension line of the second lateral passage 43. However, it may also be of the type provided laterally.

"Effects" As described above, since the three-way solenoid valve of the present invention has the above configuration, it is possible to prevent the inner valve from sinking into the stopper member while having a simple structure, and prevent leakage of magnetic flux from the stopper member to the inner valve. Since it is possible to prevent this and supply a sufficient electromagnetic attraction force, it is possible to speed up the operational response of the outer valve. Furthermore, since it is possible to supply sufficient electromagnetic attraction force, the three-way solenoid valve can be downsized. Furthermore, it has excellent effects such as being able to reliably open and close the valve seat.

[Brief explanation of the drawing]

Fig. 1 is a schematic sectional view showing an embodiment of the present invention, Fig. 2 is a schematic sectional view explaining the present invention in detail, Fig. 3 is a characteristic diagram showing the effects of the present invention, and Fig. 4 is a conventional three-sided A configuration diagram of a fuel injection device using a solenoid valve, FIG. 5 is a schematic sectional view for explaining the structure of a conventional three-way solenoid valve, and FIG. 6 is a schematic sectional view showing another embodiment of the present invention. . 30. Valve body 37. ,,first valve seat,38
1. First fitting hole, 39, outer valve, 40
, ,Poppet section 41 , ,Armature 45
,,,second valve seat, 46. ,, second fitting hole, 471,
Inner valve, 48. ,, poppet section, 51. . , solenoid coil, 52. ,, spring, 60
,,,three-way solenoid valve, 61,,,iron core, 61a,
,. Center core member, 61b, outer core member, 62.7
1. ,, Stopper member, 66 ,, Minute length, X0
1. Fluid supply port, Y09. Fluid extraction port, Z1
9. Fluid drain port. Figure 1 Figure 2 Figure 3 Figure 3 (A) Figure 4 Figure 5

Claims (1)

[Claims] It has a fluid supply port, a fluid take-out port, and a fluid discharge port, and has a first valve seat in the middle of a passage connecting the fluid take-out port and the fluid discharge port, and faces the first valve seat. a valve body provided with a first fitting hole at a position; a valve body slidably fitted into the first fitting hole so as to be able to come into and out of contact with the first valve seat; a second valve seat in the middle of a passage connecting the second valve seat and the second valve seat;
A second fitting hole is provided at a position facing the valve seat, and
an outer valve having a flange-shaped portion formed on its upper portion; an inner valve slidably fitted into the second fitting hole so as to be able to come into contact with and separate from the second valve seat; and a center facing the flange-shaped portion of the outer valve. an iron core member, an electromagnetic coil disposed on the outer periphery of the central iron core member, an outer peripheral iron core member located on the outer periphery of the electromagnetic coil and substantially facing the flange-shaped portion, and an approximately central portion of the central iron core member. A three-way solenoid valve characterized by comprising a stopper member made of a hard non-magnetic material and arranged to come into contact with the upper end surface of the inner valve.