JPH0619674B2 - Negative pressure regulator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Industrial field of application) The present invention is directed to recirculating exhaust gas discharged from a combustion engine in an automobile or the like, thereby reducing NOx value contained in the exhaust gas. The present invention relates to a negative pressure regulator used in a recirculation device (EGR) that reduces the noise.

(Prior Art) As shown in FIG. 4, a conventional negative pressure regulator has a negative pressure circuit 1
A negative pressure introducing pipe 3 having an orifice 2 and directly connected to a recirculation device (EGR) is connected, and the atmosphere adjusted by a negative pressure regulator 4 is introduced in the middle of the negative pressure introducing pipe 3. Has become. The negative pressure regulator 4 has a negative pressure introducing path 5 communicating with the negative pressure introducing pipe 3 and an output introducing path 6 communicating with the negative pressure circuit 1. The output introducing path 6 is driven by a plunger 7 that is excited. The negative pressure introducing passage 5 is closed by the diaphragm 8 connected to the plunger 7 so that it can be opened and closed. When the diaphragm 7 is driven to open, the diaphragm 8 opens the negative pressure introducing passage 5 so that the atmosphere intake port 9 is opened and the atmosphere is introduced into the negative pressure introducing passage 5.

(Problems to be Solved by the Invention) In the conventional negative pressure regulator, only the amount of air introduced into the middle of the negative pressure introducing pipe 3 is adjusted. The number of connecting points of the pressure circuit 1 and the negative pressure regulator 4 is large, the structure is complicated and large, and the number of parts is large and the cost is high. Further, since the diaphragm 8 is used to introduce the atmosphere, it has poor responsiveness and has problems in durability and cost.

Further, the negative pressure introduced from the negative pressure nozzle connected to the intake manifold fluctuates drastically due to the engine load, and it is difficult to keep the constant negative pressure at all times.

The present invention has been made in view of the above points, and has excellent responsiveness and durability, and is provided with an external regulator, a tank, etc. even when the intake manifold negative pressure is changed due to a change in engine load or the like. It is an object of the present invention to provide a small-sized and inexpensive negative pressure regulator that does not require the.

[Structure of Invention]

(Means for Solving the Problems) A negative pressure regulator of the present invention includes a fixed iron core 11 having an air intake 13, a coil 16 arranged around the fixed iron core 11 in an airtight state, and this coil. A housing 21 that is arranged in an airtight state around 16 and an annular sheet 46 that is airtightly fixed with a gap between the housing 21 and the end surface of the fixed iron core 11 where the atmosphere intake port 13 opens. A negative pressure introducing hole 36 having an orifice 35 and an output nozzle 38 communicate with each other, and a first negative pressure chamber 32 communicating with the atmosphere intake port 13 and a body 31 fixed to the housing 21 in an airtight state. An armature 44 made of a magnetic material which is disposed in the first negative pressure chamber 32 of the body 31 and is urged by a spring 45 in a pressure-tight manner to the seat 46, and the first negative pressure chamber 32. The adjusting chamber 62 communicated with the negative pressure introducing hole 36 and the adjusting chamber 62. A regulator diaphragm 60, the needle of which one end is opened and closed by the regulator diaphragm 60
A second negative pressure chamber 50, the other end of which communicates with the other through a check valve 59, a spring 66 attached to the regulator diaphragm 60, and a negative pressure nozzle 53 which communicates with the second negative pressure chamber 50. The regulator diaphragm 60 and the negative pressure of the adjusting chamber 62 determined by the spring 66 and the duty time control of the pulse signal to the coil 16 control the opening / closing time by the contact and separation of the armature 44 with respect to the seat 46. By adjusting the first negative pressure chamber 32 of the body 31
It obtains the required negative pressure.

(Operation) According to the present invention, when the regulator diaphragm 60 that abuts and closes one end of the needle 64 and the force of the spring 66 are balanced, the vacuum degree of the adjustment chamber 62 is kept and the negative pressure is kept constant. Negative pressure introduction hole 36 with orifice 35 in
The duty time of the pulse signal to the coil 16 according to the negative pressure state of the first negative pressure chamber 32 which is in communication with the atmosphere intake port 13 which is in communication with the output nozzle 38 and is opened and closed by the armature 44. Control armature
The negative pressure required in the first negative pressure chamber 32 is obtained by adjusting the ratio of the opening / closing time depending on the contact and separation of 44 with respect to the seat 46.

(Embodiment) Hereinafter, a configuration of an embodiment of the present invention will be described with reference to FIGS. 1 to 3.

In FIG. 1, 11 is a fixed iron core, and the fixed iron core 11 is formed with an air intake port 13 penetrating the center thereof and opening to an air intake nozzle 12 at one end and the other end thereof. A ring groove 15 into which an annular O-ring 14 is fitted is formed in an annular shape on the outer peripheral surface of the iron core 11.

On the outer circumference of the fixed iron core 11, the O
A coil bobbin 17 in which a coil 16 is wound around the outer periphery by being crimped onto the ring 14 is arranged in an airtight state. This coil bobbin 17
A ring groove 19 into which an annular O-ring 18 is fitted is formed in a ring shape on the outer peripheral surface of the lower end portion of, and a relief groove 20 is formed on the inner peripheral surface.

On the outer periphery of the coil bobbin 17, a cylindrical housing 21 is arranged in an airtight state by being crimped to an O-ring 18 fitted in a ring groove 19. A lead-out hole 23 through which a lead wire 22 connected to the coil 16 is drawn out of the housing 21 is formed on the outside of the upper end of the housing 21.
Locking claws 24 are provided at three locations on the upper end of 21. The locking claws 24 are engaged with the upper surface of an annular plate 25 that is inserted into the fixed iron core 11 and abuts on the upper end of the coil bobbin 17. Are fixed together. The plate 25 is formed with an engaging groove 26 for engaging the locking claw 24 on the outer peripheral edge portion, and the fixed iron core 11 is caulked and fixed to the inner peripheral edge portion.

31 is a body, and this body 31 is an annular first opening that opens to the upper surface.
The negative pressure chamber frame 33 that constitutes the negative pressure chamber 32 of
On the lower surface of 33, the negative pressure introduced from the negative pressure adjusting section 34 provided at the lower portion of the body 31 in communication with the first negative pressure chamber 32 is stably fed to the first negative pressure chamber 32. Orifice for feeding 35
Is provided with a negative pressure introducing hole 36, and an output nozzle 38 having an output introducing port 37 communicating with the first negative pressure chamber 32 is provided. Further, a flange portion 39 attached to the lower portion of the housing 21 is provided on the outer peripheral portion of the upper end of the negative pressure chamber frame 33, and an annular O-shape is formed on the upper surface of the flange portion 39.
A ring groove 41 into which the ring 40 is fitted is provided in an annular shape, and the O-ring 40 fitted into the ring groove 40 is crimped to crimp a fixing claw 42 provided at the lower end of the housing 21, thereby The body 31 is fixed to the housing 21 in an airtight state.

In addition, in the center of the first negative pressure chamber 32 of the body 31, a cylindrical frame 43 is formed.
Is provided between the upper end of the cylindrical frame 43 and the lower surface of the fixed iron core 11, and the armature 44 is formed of a magnetic material in a disc shape.
Is arranged so as to be movable in the vertical direction in the first negative pressure chamber 32,
The armature 44 is urged toward the lower surface of the fixed iron core 11 by a spring 45 arranged between the armature 44 and the bottom of the first negative pressure chamber 32.

At the outer periphery of the lower end, which is one end of the fixed iron core 11, a sheet 46 annularly formed of a non-magnetic material to prevent residual magnetism is press-fitted, and the lower end of the sheet 46 is biased by a spring 45. The armature 44 is pressed in an airtight state.
Further, a gap 47 is formed between the lower end of the sheet 46, that is, the upper surface of the armature 44 and the lower surface of the fixed iron core 11 in order to obtain an effective area on the atmosphere side flowing in from the atmosphere intake port 13.

A concave portion that forms the second negative pressure chamber 50 is formed in the lower portion of the body 31.
An opening 51 is formed on the lower surface. A negative pressure inlet 52 communicating with the second negative pressure chamber 50 is formed above the recess 51,
For example, a negative pressure nozzle connected to the intake manifold
53 is provided, and in the second negative pressure chamber 50,
A carrier 56 is provided below the concave portion 51 so as to face it and hermetically weld the outer peripheral edge of the holder to form a reservoir chamber 57.

The holder 54 of the reservoir chamber 57 has a hole for introducing negative pressure.
A check valve 59 is provided so as to cover the hole 58 and maintain a high vacuum.

Further, 60 is a regulator diaphragm having a thick sheet portion 61 in the center, and an adjusting chamber 62 is provided between the regulator diaphragm 60 and the carrier 56, and the negative pressure introducing hole 36 is formed in the carrier 56 from the adjusting chamber 62. Communication hole 63 formed in the peripheral portion of the groove 55 and the regulator diaphragm 60.
Are communicated with. Further, a needle 64 is provided at the center of the carrier 56, and the upper end of the needle 64 has a reservoir chamber 57
The lower end of the regulator diaphragm 60 is in contact with the thick-walled sheet portion 61 in the center of the regulator diaphragm 60 and is openably and closably closed.
In addition, the regulator diaphragm 60 has hook washers.
The other end of the spring 66 having one end locked to the hook washer 65 is attached to the lower part of the body 31 by caulking the other end of the spring 68 to the center of the lower part of the cover 68 for tension adjustment.
Installed on 69.

Next, the operation of this embodiment will be described.

The negative pressure from the intake manifold flows into the second negative pressure chamber 50 via the negative pressure inlet 52 of the negative pressure nozzle 53, passes through the hole 58 of the check valve 59, and enters the reservoir chamber 57.

The needle 64 contacts the regulator diaphragm 60 and is closed. And regulator diaphragm 60
When the hook washer 65 built in is pulled downward by the force of the spring 66, the lower end of the needle 64 separates from the regulator diaphragm 60, the reservoir chamber 57 and the adjusting chamber 62 communicate with each other, and the negative pressure in the adjusting chamber 62 increases. At this time, the force of the regulator diaphragm 60 in the upward direction increases and is returned against the spring 66 to balance the force of the spring 66 and the needle 64.
Lower end of the regulator and thick-walled sheet portion 61 of the regulator diaphragm 60
And abut each other, and the degree of vacuum is maintained. Then, the negative pressure passes through the groove 55 provided in the carrier 56 and the communication hole 63 of the regulator diaphragm 60 and is guided to the negative pressure introducing hole 36 to generate a negative pressure corresponding to the load of the spring 66, so that the negative pressure is always constant. To do.

When the negative pressure nozzles 38 and 53 are opened to the atmosphere and there is no pressure difference between the upper and lower sides of the armature 44 when the coil 16 is not energized, or when the pressure difference is small, the armature 44 is attached to the seat 46 by the urging force of the spring 45. It is in close contact.

When the coil 16 is not energized, the vacuum degree of the first negative pressure chamber 32 increases, and the atmosphere above and below the armature 44 and the first negative pressure chamber 32.
When a pressure difference occurs between the armature 44 and the spring 45
Is pushed down against the end face of the seat 46, and the atmosphere intake port 13 is inserted between the armature 44 and the seat 46.
After that, the atmosphere flows into the first negative pressure chamber 32, and the degree of vacuum in the first negative pressure chamber 32 is lowered. It should be noted that how much the degree of vacuum is lowered is determined by the non-energization time to the coil 16.

When the coil 16 is energized, the fixed iron core 11 is excited and the armature 44 is attracted to the end surface of the seat 46, and the first negative pressure chamber
The air is prevented from flowing into the inside 32, and the degree of vacuum in the first negative pressure chamber 32 is increased.

Each of the above operations is required in the first negative pressure chamber 32 by adjusting the ratio of the opening / closing operation time of the armature 44 by the duty time control of the pulse signal controlled by the computer to the coil 16. A negative pressure can be obtained.

Note that it is sufficient to connect only the negative pressure introducing hole 36 and the output nozzle 38 to the negative pressure circuit.

In addition, the introduction of the atmosphere into the first negative pressure chamber 32 uses a spring.
Since it is performed by the armature 44 urged by 45, the response to the negative pressure fluctuation in the first negative pressure chamber 32 is good.

〔The invention's effect〕

According to the present invention, the negative pressure introducing hole having the orifice and the output nozzle communicate with the negative pressure chamber of the body, and the atmosphere intake port provided in the fixed iron core communicates with the negative pressure chamber. By placing an armature that is crimped and urged and adjusting the ratio of the opening and closing time depending on the contact and separation of the armature to and from the seat by controlling the negative pressure determined by the orientation and the duty time control of the pulse signal to the coil Since the required negative pressure is obtained in the negative pressure chamber, the negative pressure is accurately adjusted by introducing the atmosphere in the negative pressure chamber of the body, and the regulator diaphragm and spring are balanced. By the way, since it abuts on the needle and closes it, a constant negative pressure can be introduced to the negative pressure introduction hole regardless of the change in the negative pressure introduced, and the negative pressure circuit is connected to the negative pressure circuit. Since only the negative pressure introduction nozzle and the output nozzle need to be connected, the number of connection points is reduced, the negative pressure circuit configuration is simplified and downsized, the cost is reduced by reducing the number of parts, and the introduction of the atmosphere Is performed by the opening / closing operation of the armature urged by the spring, the response to negative pressure fluctuation is good, the cost is low, and the durability is excellent.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing the construction of an embodiment of the negative pressure regulator of the present invention, FIGS. 2 and 3 are horizontal sectional views of the same as above, and FIG. 4 is a vertical sectional view of a conventional negative pressure regulator. Is. 11 …… Fixed iron core, 13 …… Atmosphere inlet, 16 …… Coil,
21 ... Housing, 31 ... Body, 32 ... First negative pressure chamber,
35 ... Orifice, 36 ... Negative pressure introduction hole, 38 ... Output nozzle, 44 ... Armature, 45 ... Spring, 46 ... Seat, 50 ... Second negative pressure chamber, 53 ... Negative pressure nozzle , 59 ……
Check valve, 60 ... Regulator diaphragm, 62
…… Adjustment chamber, 64 …… Needle, 66 …… Spring.

Claims (1)

[Claims] 1. A fixed iron core 11 having an air intake 13, and a coil 16 arranged around the fixed iron core 11 in an airtight state.
And a housing placed around this coil 16 in an airtight manner
21, an annular seat 46 that is airtightly fixed around the inner end face where the air intake port 13 of the fixed iron core 11 is open with a gap between the end face and the negative pressure introduction hole 36 and the orifice 35. Output nozzle 38
Communication with the above-mentioned atmosphere intake port 13
A negative pressure chamber 32, which is fixed to the housing 21 in an airtight state, and a spring 45 arranged in the first negative pressure chamber 32 of the negative pressure chamber 32.
The armature 44 made of a magnetic material that is pressed and urged to the seat 46 in an airtight manner by the above, the adjustment chamber 62 communicating with the first negative pressure chamber 32 through the negative pressure introduction hole 36, and the adjustment chamber 62. Regulator diaphragm 60 installed in
A second negative pressure chamber 50 in which the other end of the needle 64 whose one end is opened and closed by the regulator diaphragm 60 communicates via a check valve 59; a spring 66 attached to the regulator diaphragm 60; The negative pressure nozzle 53 communicating with the second negative pressure chamber 50, and the negative pressure of the adjusting chamber 62 determined by the regulator diaphragm 60 and the spring 66 and the duty time control of the pulse signal to the coil 16 to control the armature 44. A negative pressure regulator, characterized in that a required negative pressure is obtained in the first negative pressure chamber 32 of the body 31 by adjusting the opening / closing time ratio by contacting and separating the sheet 46 with the seat 46.