JP2000038959A - Lpg regulator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To keep the low speed performance of an internal combustion engine stable by letting the quantity of imprities such as a tar constituent, in LPG fuel attached to the measuring part of a low speed fuel measuring device be reduced, and concurrently, reduce the adjustment frequency of the low speed fuel measuring device. SOLUTION: In this regulator, a closing valve 18 and a low speed fuel measuring device 21 are respectively provided in a low speed fuel passage 17 branched out of a primary decompression chamber 7, and a place located at the downstream of the chamber 7, fuel for low speed is thereby led to a main fuel passage 30 at the time of normal operation through the low speed fuel passage 17. In this case, a filter 19 for removing impurities contained in fuel such as a tar constituent, is provided for the low speed fuel passage 17 interposed between the primary decompression chamber 7 and the low speed fuel measuring device 21.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an LPG regulator for an internal combustion engine, and more particularly to the removal of impurities such as tar components in fuel generated in the regulator.

[0002]

2. Description of the Related Art Conventionally, LPG fuel supplied to an internal combustion engine driven by LPG fuel is kept in a liquid state in an LPG cylinder, and after most impurities have been removed by a filter, an inlet 2 shown in FIG. To LPG regulator 10
0 (hereinafter referred to as a regulator)
And the gas is decompressed and vaporized in the secondary decompression chamber 8, and the main fuel passage 3
0, and is supplied to a combustion chamber of an internal combustion engine (not shown) through an LPG vaporizer (not shown) via an outlet 3. The internal combustion engine is driven by the decompressed and vaporized LPG fuel in the secondary decompression chamber 8 during normal operation at medium to high speeds, and a slow speed branch provided from the primary pressure reduction chamber 7 during idling and slow operation. Driven by the fuel flowing through the fuel passage 17. In the middle of the slow fuel passage 17, a slow fuel passage 17 is provided.
An opening / closing valve 18 is provided to open / close the slow fuel passage 17 by an electric signal from an exhaust gas control device (not shown) at the time of deceleration or the like to save fuel. Downstream of the on-off valve 18, a slow fuel metering device 21 for adjusting the slow fuel amount is provided, and a taper portion 21 at the tip of an adjusting screw 21a of the slow fuel metering device 21 is provided.
The fuel amount is adjusted by increasing or decreasing the small annular gap between the fuel passage measuring portion 17b and the slow fuel passage measuring portion 17b.

Further, a filter is provided in a main fuel passage outside the regulator, that is, a fuel passage through which fuel at a medium to high speed is circulated to remove impurities in the fuel, for example, as disclosed in Japanese Utility Model Laid-Open No. 56-167770. However, in this case, the concept of providing a filter in the slow fuel passage 17 is not shown.

[0004]

However, since the adjustment of the amount of slow fuel in the slow fuel passage 17 is performed in a very small amount, the minute annular gap is extremely small, about 50 μm. Therefore, in the case where the minute annular gap is adjusted by the slow fuel metering device 21 without providing a filter in the slow fuel passage as described above, in the LPG fuel, impurities such as tar components contained in the small It adheres to the gap and the opening area gradually becomes smaller. As a result, the amount of slow-speed fuel becomes insufficient, the engine speed decreases, and in the worst case, the engine stops. For this reason, the adjusting screw 21a of the slow fuel metering device 21 needs to be adjusted frequently, which is extremely time-consuming.

Accordingly, a first object of the present invention is to provide a filter in a slow fuel passage, in particular, to reduce the amount of impurities such as tar adhering to the minute annular gap and maintain a stable slow performance of the engine. Another object of the present invention is to reduce the frequency of adjusting the adjusting screw.

A second object is to facilitate cleaning and replacement of a filter provided in the slow fuel passage.

[0007]

According to a first aspect of the present invention, an on-off valve is provided in a slow fuel passage branched from a primary pressure reducing chamber and a valve located downstream of the on-off valve. An LPG regulator provided with a slow-speed fuel metering device, wherein the slow-speed fuel is guided to the main fuel passage during normal operation through the slow-speed fuel passage; And a filter for removing impurities such as tar contained in the fuel is provided in the slow fuel passage between the fuel cell and the fuel cell.

In the present invention, a filter for removing impurities such as tar is provided between the primary pressure reducing chamber and the slow fuel measuring device in the slow fuel passage branched from the primary pressure reducing chamber. Therefore, impurities such as tar are removed, the adhesion of the impurities to the minute annular gap is reduced, the stable slow performance of the engine is maintained, and the frequency of adjusting the adjusting screw is reduced.

According to a second aspect of the present invention, an opening / closing valve is provided in a slow fuel passage branched from the primary pressure reducing chamber, and a slow fuel measuring device is provided downstream of the open / close valve. In the LPG regulator guided to the main fuel passage during normal operation through the slow fuel passage, a part of the slow fuel passage from the on-off valve to the main fuel passage is led out of the regulator main body. A filter for removing impurities such as tar contained in the fuel is provided in a slow fuel passage outside the regulator body.

In the present invention, since the filter is provided outside the regulator body, the filter can be cleaned and replaced regardless of the components attached to the regulator body.

According to a third aspect of the present invention, an opening / closing valve is provided in a slow fuel passage branched from the primary pressure reducing chamber and a slow fuel metering device is provided downstream of the open / close valve. In the LPG regulator guided to the main fuel passage during normal operation through the slow fuel passage, a part of the slow fuel passage from the on-off valve to the main fuel passage is led out of the regulator main body. A filter case is provided in the slow fuel passage outside the regulator body, and a filter for removing impurities such as tar contained in the fuel in the case, and a slow fuel metering device located downstream of the filter. An apparatus is provided, the case is detachably provided on the regulator body, and the filter is detachably provided on the case.

In the present invention, the filter case can be removed from the regulator body, and the filter can be removed from the case for cleaning and replacement. The fourth invention according to claim 4 is the first invention or the second or third invention.
In the invention, the filter comprises a metal or synthetic resin filter body and a sintered alloy or polyvinyl formal (PVF) sponge filter element, and the filter body is a cartridge type in which the filter element is press-fitted inside. It is characterized by having a structure.

In the present invention, the filter comprises a metal or synthetic resin filter body and a sintered alloy or polyvinyl formal (PVF) sponge filter element, and the filter element is press-fitted inside. Since the cartridge type structure is used, the filter can be easily removed, and the filter element can be easily cleaned or replaced, so that a filter device which is easy to handle can be provided.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a first embodiment.

In the first embodiment, the regulator 1
The regulator body 1a has an inlet 2 for introducing LPG fuel sent from an LPG cylinder (not shown) through a filter (not shown), and an L port (not shown) for depressurized and vaporized fuel.
A main fuel passage 30 for medium and high speed feeding to the PG vaporizer is provided, a partition wall 4 that divides the regulator main body 1 into two, and first and second diaphragms 5 and 6 extended inside the primary pressure reducing chamber 7. A secondary decompression chamber 8 is formed.
When passing through the primary decompression chamber 7 and the secondary decompression chamber 8, the LPG fuel flowing from the inlet 2 is decompressed and vaporized to form the main fuel passage 3.
0 or flows through a slow fuel passage 17 to be described later, and flows out from an outlet 3 formed of a main union 3a to an LPG vaporizer (not shown).

A partition 4 on the side of the primary decompression chamber 7 has inlets 2 and 1
A first lever 11 having a primary pressure reducing valve 10 for opening and closing the first passage 9 between the secondary pressure reducing chamber 7 and the secondary pressure reducing chamber 7 is rotatably supported. The primary pressure reducing valve 10 is fixed to the distal end of the short arm of the first lever 11, and the distal end of the long arm is engaged with the first diaphragm 5. The first diaphragm 5 is pressed by the first spring 12 in a direction in which the primary pressure reducing valve 10 opens, and the pressure in the primary pressure reducing chamber 7 increases with the inflow of the LPG fuel, and the first diaphragm 12 resists the first spring 12. As the first diaphragm 5 expands outward, the primary pressure reducing valve 10 closes the first passage 9 and opens the first passage 9 when the LPG fuel in the primary pressure reducing chamber 7 is consumed. The pressure in the next decompression chamber 7 is configured to be kept constant.

The partition 4 on the side of the secondary pressure reducing chamber 8 has a secondary pressure reducing valve 14 for opening and closing a second passage 13 between the primary pressure reducing chamber 7 and the secondary pressure reducing chamber 8. The second lever 15 is pivotally supported so as to be rotatable. The secondary pressure reducing valve 14 is fixed to the distal end of the short arm of the second lever 15, and the distal end of the long arm is engaged with the second diaphragm 6. The second diaphragm 6 is pressed by the second spring 16 in a direction in which the secondary pressure reducing valve 14 is closed. As the LPG fuel is consumed from the outlet 3, the pressure in the secondary pressure reducing chamber 8 decreases and the second spring 16 The second pressure reducing valve 14 opens the second passage 13 as the second diaphragm 6 contracts inward against the second diaphragm 16,
The LPG fuel in the primary decompression chamber 7 flows into the secondary decompression chamber 8, and the pressure in the secondary decompression chamber 8 is kept constant.

From the primary pressure reducing chamber 7 to the slow fuel passage 17
A filter 19 is provided in the slow fuel passage 17 between the primary decompression chamber 7 and the opening / closing valve 18, which are branched. The filter 19 includes a filter body 19a and a filter element 19b.
The filter body 19a is formed in a cylindrical shape having a flange 19c, and inside the cylinder is made of a sintered alloy, for example, a bronze sintered alloy or polyvinyl formal (PVF).
The filter element 19b made of sponge has a so-called cartridge type structure in which the filter element 19b is press-fitted so as not to protrude from the filter body 19a due to the pressure of the LPG fuel.
An O-ring (seal member) 20 is mounted between a flange 19c of the filter main body 19a and a step 17a provided in the slow fuel passage 17, and is pressed by an on-off valve 18 so that an outer periphery of the filter main body 19a is provided. It is configured to maintain airtightness between the fuel passage 17 and the slow fuel passage 17.

The on-off valve 18 comprises a valve seat 18b press-fitted through a sealing material 18a such as an O-ring and a valve body 18c which comes into contact with and separates from the valve seat 18b. Next, the operation of the present embodiment will be described in detail.

In FIG. 1, when the secondary pressure reducing valve 14 is opened, LPG fuel for medium to high speed is sent from the outlet 3 through the main fuel passage 30 to an LPG vaporizer (not shown). Further, at the time of slow operation, the slow LPG fuel is supplied to the slow fuel passage 17.
Spill out of. At this time, impurities such as a liquid tar component generated when the pressure is reduced and vaporized in the primary decompression chamber 7 flow into the slow fuel passage 17 together with the LPG fuel, but only the liquid tar component and the like are filtered through the filter element 19b. LP
The G fuel passes through the filter element 19b, passes through the on-off valve 18, is adjusted by the slow fuel metering device 21, and
Is sent to an LPG vaporizer (not shown). Filter 19
Has a cartridge type structure so that it can be easily removed and replaced by taking out the on-off valve 18,
If the filter element 19b is made of a sintered alloy, for example, a bronze sintered alloy, the filtration function can be easily updated by washing, and if it is made of polyvinyl formal (PVF) sponge, it can be easily replaced. Becomes possible.

FIG. 2 shows a second embodiment. In the second embodiment, a passage 40 to the injector is provided in the slow fuel passage 17 between the on-off valve 18 and the slow fuel metering device 21 in the first embodiment. The slow fuel metering device 21 is disposed downstream of the section. Since other structures are the same as those of the first embodiment, the same parts as those described above are denoted by the same reference numerals and description thereof will be omitted.

The second embodiment can exhibit the same operation and effects as those of the first embodiment. In the first and second embodiments, the filter 19 may be mounted in the slow fuel passage 17 between the on-off valve 18 and the slow fuel metering device 21.

One example of such an embodiment is shown in FIGS. 3 to 5 as a third embodiment. FIG. 3 is a schematic view of the connection of the filter subassembly 52 to the regulator main body 1a, FIG. 4 is a front view of the state where the filter subassembly 52 is mounted on the regulator main body 1a, and FIG.
FIG.

In FIG. 3, the opening / closing valve 18 press-fits a valve seat 18b into a slow fuel passage 17 via an O-ring 18a, and a valve body 18c advances and retreats into the slow fuel passage 17. It is configured to open and close. The filter 19 is not mounted on the valve seat 18b.

A portion of the slow fuel passage 17 downstream of the valve seat 18b is once opened to the outside of the regulator body 1a, and a slow union 50 is provided in the portion. A passage 40 to the injector is branched from the slow fuel passage 17 between the valve seat 18b and the slow union 50 in the same manner as described above.

An upstream hose 51 forming the slow fuel passage 17 is connected to the slow union 50, and a filter sub-assembly 52 formed separately from the regulator body 1a downstream of the upstream hose 51. Is connected. Case 53 of the filter sub-assembly 52
Is formed with a concave filter housing portion 54 having an open end, and a filter 55 is fitted and mounted in the filter housing portion 54. The filter 55 is made of a metal or synthetic resin and has a cylindrical filter body 55a and a bronze sintered alloy, a stainless steel sintered alloy, or a polyvinyl formal (PVF) sponge. And a filter element 55b.
b is pressed into the filter main body 55a to form a cartridge type structure. In the example of FIG. 3, the filter element 55
b is inserted with its bottom wall 55c in the back and the opening side 55d facing the entrance side. Note that this filter element 55b
May be inserted and installed in a direction opposite to the above with the bottom wall 55c as the entrance side.

The filter main body 55a is not always necessary. If the filter element 55b itself has rigidity, only the filter element 55b may be used. A sealing member 56 such as an O-ring is
The cover 57 is hermetically mounted via a cover, and the cover 57 is detachably fixed to the case 53 with screws or the like. Further, an upstream connection pipe 58 communicating with the filter storage portion 54 is fixed to the cover 57, and the upstream hose 51 is connected to the upstream connection pipe 58.

In the case 53, a slow fuel passage 17b communicating with a bottom portion of the filter accommodating portion 54 and a downstream connection pipe 59 provided in the case 53 is formed. Further, an adjusting screw 21a of the slow fuel metering device 21 is screwed into the case 53.
The tapered portion 21a of 1a faces the slow fuel passage 17b, and the small annular gap between the tapered portion 21b and the slow fuel passage 17b is increased or decreased to adjust the slow fuel amount.

A downstream hose 60 is connected to the downstream connection pipe 59, and the downstream side thereof is connected to a connection pipe 61 provided in the main fuel passage 30 so as to be connected to the main fuel passage 30. Communicating.

Since the other structure is the same as that of the first embodiment, the same parts as those described above are denoted by the same reference numerals and description thereof will be omitted. The filter sub-assembly 52 includes a regulator body 1a as shown in FIGS.
Is detachably fixed by a bolt 62.

Also in the third embodiment, the secondary pressure reducing valve 14
Is opened, the LPG fuel for medium and high speeds is supplied to the main fuel passage 3
After passing through 0, it is sent from the outlet 3 to an LPG vaporizer (not shown). In addition, at the time of slow operation, the slow LPG fuel flows out of the slow fuel passage 17. At this time, impurities such as liquid tar components generated when the pressure is reduced and vaporized in the primary decompression chamber 7 flow into the slow fuel passages 17 and 17b together with the LPG fuel, but only impurities such as liquid tar components are contained in the filter element 55b. The LPG fuel is filtered through the filter element 55b, adjusted by the slow fuel metering device 21, and sent from the outlet 3 to an LPG vaporizer (not shown).

When impurities such as tar adhere to the filter element 55b and are removed therefrom, the upstream connection pipe 58 of the filter sub-assembly 52 is disconnected from the upstream hose 51, and the downstream connection pipe 59 is removed. Is removed from the downstream hose 60, and the filter sub-assembly 52 is removed from the regulator body 1a. Then, the cover 57 is removed from the case 53, the filter 55 is removed from the filter housing portion 54, and the filter element 55 is removed.
b is cleaned with air or the like. Then, the cleaned filter 55 is inserted again into the filter housing portion 54, and the cover 5
7 is attached.

The non-reusable filter element 55b
Is replaced with a new one. After the filter 55 is removed, the filter housing portion 54 has a large space, so that the slow-speed fuel metering portion in the deep portion can be easily cleaned.

Further, in the third embodiment, since the filter 55 is provided as the filter sub-assembly 52 separate from the regulator main body 1a, the following effects are obtained.

In the embodiment shown in FIGS. 1 and 2, when the filter element 19b is removed for cleaning, the on-off valve 18 must be removed from the regulator body 1a together with the valve seat 18b. However, if the on-off valve 18 is removed together with the valve seat 18b every time the filter element 19b is cleaned, the sealing member 18a such as an O-ring provided on the valve seat 18b may be damaged or cut. On the other hand, as in the third embodiment, the filter 55 is formed as a separate filter sub-assembly from the regulator main body 1a.
Since there is no need to remove the valve seat 18b of FIG. 8, there is no possibility that the seal member 18a may be damaged or cut as described above.

[0036]

The present invention has the following effects because it is configured as described above. That is, a filter for removing impurities such as tar is provided between the primary pressure reducing chamber and the slow fuel metering device in the slow fuel passage branched from the primary pressure reducing chamber. Impurities are removed,
The adhesion of impurities to the minute annular gap is reduced, and stable slow performance of the engine can be maintained, and the frequency of adjustment of the adjusting screw of the slow fuel metering device can be reduced.

Also, a part of the slow fuel passage from the on-off valve to the main fuel passage is led out of the regulator body, and the slow fuel passage outside the regulator body is provided. By providing a filter for removing impurities such as tar contained in the fuel, the following effects can be obtained.

That is, as shown in FIG. 1, in the case of a structure in which a filter is embedded in the slow fuel passage in the regulator body and a valve seat of the on-off valve is embedded outside the filter, every time the filter is cleaned. It is necessary to remove the valve seat together with the on-off valve. When the valve seat is removed together with the on-off valve,
A sealing material such as an O-ring press-fitted together with the valve seat is twisted by a frictional force at the time of removal or attachment, and the sealing material may be damaged or cut. However, by providing the filter outside the regulator body as in the invention according to the second aspect, the filter can be cleaned and replaced independently of the valve seat of the on-off valve. Cutting damage can be prevented.

Further, in the invention according to the third aspect, the filter case is detachably provided on the regulator body and the filter is detachably provided on the case, so that the filter can be cleaned or replaced, and the slow fuel metering can be performed. The part can be easily cleaned.

According to the fourth aspect of the present invention, since the filter has a cartridge type structure, the filter can be easily removed and repaired easily. Further, when the filter element is made of a sintered alloy, the filtration performance can be updated by washing, and when the filter element is made of polyvinyl formal (PVF) sponge, it can be easily replaced.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an LPG regulator showing a first embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of an LPG regulator showing a second embodiment of the present invention.

FIG. 3 illustrates a third embodiment of the present invention, and is a longitudinal sectional view schematically illustrating connection of a filter subassembly to an LPG regulator.

FIG. 4 is a front view of the LPG regulator with the filter subassembly mounted in the embodiment of FIG. 3;

FIG. 5 is a right side view of FIG.

FIG. 6 is a longitudinal sectional view of an LPG regulator showing a conventional technique.

[Explanation of symbols]

 Reference Signs List 1 Regulator 7 Primary decompression chamber 8 Secondary decompression chamber 17, 17b Slow fuel passage 17a Step 18 Opening / closing valve 18a O-ring (seal member) 19, 55 Filter 19a, 55a Filter body 19b, 55b Filter element 21 Slow Fuel metering device 30 Main fuel passage

Continued on the front page (72) Inventor Kazunori Ishii 1-1 1-1 Kyowa-cho, Obu City, Aichi Prefecture Inside Ai San Kogyo Co., Ltd. Inside

Claims (4)

[Claims] An opening / closing valve is provided in a slow fuel passage branched from a primary pressure reducing chamber, and a slow fuel metering device is provided downstream thereof, and the slow fuel passes through the slow fuel passage. In the LPG regulator guided to the main fuel passage during normal operation, impurities such as tar contained in fuel are removed in the slow fuel passage between the primary pressure reducing chamber and the slow fuel metering device. LPG regulator characterized by having provided a filter for performing. 2. An on-off valve and a slow fuel metering device are provided in the slow fuel passage branched from the primary pressure reducing chamber, and the slow fuel is disposed downstream of the open / close valve. The slow fuel passes through the slow fuel passage. In the LPG regulator guided to the main fuel passage during normal operation, a part of the slow fuel passage from the on-off valve to the main fuel passage is led out of the regulator body, and the slow fuel passage outside the regulator body is provided. An LPG regulator, further comprising a filter for removing impurities such as tar contained in the fuel. 3. An on-off valve and a slow fuel metering device are provided in the slow fuel passage branched from the primary decompression chamber and located downstream of the slow fuel passage, and the slow fuel passes through the slow fuel passage. In the LPG regulator guided to the main fuel passage during normal operation, a part of the slow fuel passage from the on-off valve to the main fuel passage is led out of the regulator body, and the slow fuel passage outside the regulator body is provided. A filter case, a filter for removing impurities such as tar contained in fuel in the case, and a slow fuel metering device located downstream of the filter. An LPG regulator, wherein the filter is detachably provided in the case, and the filter is detachably provided in the case. 4. The filter comprises a metal or synthetic resin filter body and a sintered alloy or polyvinyl formal (PVF) sponge filter element, and the filter body is a cartridge into which the filter element is press-fitted. 4. The LPG regulator according to claim 1, wherein the LPG regulator has a formula structure.